WorldWideScience

Sample records for residential duct systems

  1. Duct System Flammability and Air Sealing Fire Separation Assemblies in the International Residential Code

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.; Prahl, D.

    2014-12-01

    IBACOS identified two barriers that limit the ability of builders to cost-effectively achieve higher energy efficiency levels in housing. These are (1) the use of duct system materials that inherently achieve airtightness and are appropriately sized for low-load houses and (2) the ability to air seal fire separation assemblies. The issues identified fall into a gray area of the codes.

  2. Duct System Flammability and Air Sealing Fire Separation Assemblies in the International Residential Code

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A. [ABT Systems, LLC, Annville, PA (United States); Prahl, D. [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-12-01

    IBACOS identified two barriers that limit the ability of builders to cost-effectively achieve higher energy efficiency levels in housing. These are the use of duct system materials that inherently achieve airtightness and are appropriately sized for low-load houses and the ability to air seal fire separation assemblies. The issues identified fall into a gray area of the codes.

  3. Comparison between predicted duct effectiveness from proposed ASHRAE Standard 152P and measured field data for residential forced air cooling systems; TOPICAL

    International Nuclear Information System (INIS)

    Siegel, Jeffrey A.; McWilliams, Jennifer A.; Walker, Iain S.

    2002-01-01

    The proposed ASHRAE Standard 152P ''Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems'' (ASHRAE 2002) has recently completed its second public review. As part of the standard development process, this study compares the forced air distribution system ratings provided by the public review draft of Standard 152P to measured field results. 58 field tests were performed on cooling systems in 11 homes in the summers of 1998 and 1999. Seven of these houses had standard attics with insulation on the attic floor and a well-vented attic space. The other four houses had unvented attics where the insulation is placed directly under the roof deck and the attic space is not deliberately vented. Each house was tested under a range of summer weather conditions at each particular site, and in some cases the amount of duct leakage was intentionally varied. The comparison between 152P predicted efficiencies and the measured results includes evaluation of the effects of weather, duct location, thermal conditions, duct leakage, and system capacity. The results showed that the difference between measured delivery effectiveness and that calculated using proposed Standard 152P is about 5 percentage points if weather data, duct leakage and air handler flow are well known. However, the accuracy of the standard is strongly dependent on having good measurements of duct leakage and system airflow. Given that the uncertainty in the measured delivery effectiveness is typically also about 5 percentage points, the Standard 152P results are acceptably close to the measured data

  4. 14 CFR 25.1103 - Induction system ducts and air duct systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction system ducts and air duct systems....1103 Induction system ducts and air duct systems. (a) Each induction system duct upstream of the first... auxiliary power unit bleed air duct systems, no hazard may result if a duct failure occurs at any point...

  5. 14 CFR 29.1103 - Induction systems ducts and air duct systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction systems ducts and air duct....1103 Induction systems ducts and air duct systems. (a) Each induction system duct upstream of the first... it might cause a fire hazard. (b) Each duct must be strong enough to prevent induction system failure...

  6. BETTER DUCT SYSTEMS FOR HOME HEATING AND COOLING.

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.

    2001-01-01

    This is a series of six guides intended to provide a working knowledge of residential heating and cooling duct systems, an understanding of the major issues concerning efficiency, comfort, health, and safety, and practical tips on installation and repair of duct systems. These guides are intended for use by contractors, system designers, advanced technicians, and other HVAC professionals. The first two guides are also intended to be accessible to the general reader.

  7. A Plug-and-Play Duct System Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Beach, Robert [IBACOS, Inc., Pittsburgh, PA (United States); Dickson, Bruce [IBACOS, Inc., Pittsburgh, PA (United States); Grisolia, Anthony [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States); Rapport, Ari [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-07-10

    This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit in the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.

  8. A Plug-and-Play Duct System Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Beach, R. [IBACOS, Inc., Pittsburgh, PA (United States); Dickson, B. [IBACOS, Inc., Pittsburgh, PA (United States); Grisolia, A. [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, A. [IBACOS, Inc., Pittsburgh, PA (United States); Rapport, A. [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-07-01

    This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit in the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.

  9. Residential Solar Systems.

    Science.gov (United States)

    Fulkerson, Dan

    This publication contains student and teacher instructional materials for a course in residential solar systems. The text is designed either as a basic solar course or as a supplement to extend student skills in areas such as architectural drafting, air conditioning and refrigeration, and plumbing. The materials are presented in four units…

  10. Field investigation of duct system performance in California light commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Delp, W.W.; Matson, N.E.; Tschudy, E. [and others

    1997-12-09

    This paper discusses field measurements of duct system performance in fifteen systems located in eight northern California buildings. Light commercial buildings, one- and two-story with package roof-top HVAC units, make up approximately 50% of the non-residential building stock in the U.S. Despite this fact little is known about the performance of these package roof-top units and their associated ductwork. These simple systems use similar duct materials and construction techniques as residential systems (which are known to be quite leaky). This paper discusses a study to characterize the buildings, quantify the duct leakage, and analyze the performance of the ductwork in these types of buildings. The study tested fifteen systems in eight different buildings located in northern California. All of these buildings had the ducts located in the cavity between the drop ceiling and the roof deck. In 50% of these buildings, this cavity was functionally outside the building`s air and thermal barriers. The effective leakage area of the ducts in this study was approximately 2.6 times that in residential buildings. This paper looks at the thermal analysis of the ducts, from the viewpoint of efficiency and thermal comfort. This includes the length of a cycle, and whether the fan is always on or if it cycles with the cooling equipment. 66% of the systems had frequent on cycles of less than 10 minutes, resulting in non-steady-state operation.

  11. INTERIOR DUCT SYSTEM DESIGN, CONSTRUCTION, AND PERFORMANCE

    Energy Technology Data Exchange (ETDEWEB)

    Janet E.R. Mcllvaine; David Beal; Philip Fairey

    2001-10-10

    By removing air distribution and conditioning equipment from unconditioned spaces, homeowners stand to benefit substantially with respect to both energy savings and indoor air quality. Duct leakage introduces: Greater heating and cooling loads from air at extreme temperatures and humidity levels; Outside air and air from unconditioned spaces that may contain air borne contaminants, combustion gases, pollen, mold spores, and/or particles of building materials; and Higher whole-house infiltration/exfiltration rates. Exemplary studies conducted since 1990 have demonstrated the prevalence of duct leakage throughout the United States and measured energy savings of approximately 20% during both heating and cooling seasons from leakage reduction. These all dealt with duct leakage to and/or from unconditioned spaces. In the building science community, leakage within the conditioned space is generally presumed to eliminate the negative consequences of duct leakage with the exception of possibly creating pressure imbalances in the house which relates to higher infiltration and/or exfiltration. The practical challenges of isolating ducts and air handlers from unconditioned spaces require builders to construct an air-tight environment for the ducts. Florida Solar Energy Center researchers worked with four builders in Texas, North Carolina, and Florida who build a furred-down chase located either in a central hallway or at the edges of rooms as an architectural detail. Some comparison homes with duct systems in attics and crawl spaces were included in the test group of more than 20 homes. Test data reveals that all of the duct/AHU systems built inside the conditioned space had lower duct leakage to unconditioned spaces than their conventional counterparts; however, none of the homes was completely free of duct leakage to unconditioned spaces. Common problems included wiring and plumbing penetrations of the chase, failure to treat the chase as an air tight space, and misguided

  12. Evaluation of PEGIT duct connection system

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Brenner, Douglas E.; Sherman, Max H.; Dickerhoff, Darryl J.

    2003-08-01

    Most air duct system components are assembled in the field and are mechanically fastened by sheet metal screws (for sheet metal-to-sheet metal) or by drawbands (for flex duct-to-sheet metal). Air sealing is separate from this mechanical fastening and is usually achieved using tape or mastic products after mechanical fastening. Field observations have shown that mechanical fastening rarely meets code or manufacturers requirements and that sealing procedures are similarly inconsistent. To address these problems, Proctor Engineering Group (PEG) is developing a system of joining ducts (called PEGIT) that combines the mechanical fastening and sealing into a single self-contained procedure. The PEGIT system uses a shaped flexible seal between specially designed sheet metal duct fittings to both seal and fasten duct sections together. Figure 1 shows the inner duct fitting complete with rubber seal. This seal provides the air seal for the completed fitting and is shaped to allow the inner and outer fittings to slide together, and then to lock the fittings in place. The illustration in Figure 2 shows the approximate cross section of the rubber seal that shows how the seal has a lip that is angled backwards. This angled lip allows the joint to be pushed together by folding flat but then its long axis makes it stiff in the pulling apart direction. This study was undertaken to assist PEG in some of the design aspects of this system and to test the performance of the PEGIT system. This study was carried out in three phases. The initial phase evaluated the performance of a preliminary seal design for the PEGIT system. After the first phase, the seal was redesigned and this new seal was evaluated in the second phase of testing. The third phase performed more detailed testing of the second seal design to optimize the production tolerances of the sheet metal fittings. This report summarizes our findings from the first two phases and provides details about the third phase of testing.

  13. 14 CFR 23.1103 - Induction system ducts.

    Science.gov (United States)

    2010-01-01

    ... engine installations, each induction system duct must be— (1) Strong enough to prevent induction system... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction system ducts. 23.1103 Section 23... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Induction System...

  14. Flexible metallic seal for transition duct in turbine system

    Science.gov (United States)

    Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

    2014-04-22

    A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a flexible metallic seal contacting the interface member to provide a seal between the interface member and the turbine section.

  15. Consistent approach to air-cleaning system duct design

    International Nuclear Information System (INIS)

    Miller, W.H.; Ornberg, S.C.; Rooney, K.L.

    1981-01-01

    Nuclear power plant air-cleaning system effectiveness is dependent on the capability of a duct system to safely convey contaminated gas to a filtration unit and subsequently to a point of discharge. This paper presents a logical and consistent design approach for selecting sheet metal ductwork construction to meet applicable criteria. The differences in design engineers' duct construction specifications are acknowledged. Typical duct construction details and suggestions for their effective use are presented. Improvements in duct design sections of ANSI/ASME N509-80 are highlighted. A detailed leakage analysis of a control room HVAC system is undertaken to illustrate the effects of conceptual design variations on duct construction requirements. Shortcomings of previously published analyses and interpretations of a current standard are included

  16. A remote joint system for large vacuum ducts

    International Nuclear Information System (INIS)

    Hagmann, D.B.; Coughlan, J.B.

    1983-01-01

    A large remote vacuum duct joining system has been developed for fusion machines that uses several two-jaw screwdriven clamps. The preferred location for clamp installation is inside the vacuum duct where access space is available for the actuating device. It also decreases space needed for handling operations exterior to the duct. The clamp system is unique in that it is low cost, applies force directly over the seal, permits leak testing to the seal annulus, is highly reliable, can be remotely replaced, and is usable on a variety of other applications

  17. Residential instability: a perspective on system imbalance.

    Science.gov (United States)

    Appleby, Lawrence; Desai, Prakash

    1987-10-01

    In an exploration of residential instability and recidivism in chronic mental patients, 215 psychiatric admissions were followed for a year after the initial episode. In addition to an unusually high incidence of residential mobility, a relationship between mobility and number of hospitalizations was evident, as were isolation, disruptive family situations, and homelessness. The needed response of the mental health system is discussed.

  18. Optimum design of the injection duct system of a stenter machine

    Energy Technology Data Exchange (ETDEWEB)

    Juraeva, Makhsuda; Song, Dong Joo [Yeungnam University, Geyongsan (Korea, Republic of); Ryu, Kyung Jin [Ajou Motor College, Boryeong (Korea, Republic of)

    2017-05-15

    Stenter machines are used for drying fabrics in the textile industry and have a heater, injection duct system, and fans inside a chamber. The injection duct system has ducts and air-injecting holes. Plane-type injection duct systems were investigated to obtain uniform airflow at the air-injecting holes. The flow field of the injection duct systems was computed using ANSYS CFX with different heights of the duct end and different shapes for the air-injecting holes. There was a high mass flow rate at the air-injecting holes and high airflow circulation inside both plane-type and mountain-type ducts at the ends. The height of the duct end was varied between 40 mm and 160 mm. The injection duct systems were analyzed with four different shapes of air-injecting holes. The circular and elliptical holes had lower standard deviations of the mass flow rate than other shapes. Relatively uniform mass flow rates were obtained in the plane-type and mountain-type duct systems when the height of the duct end was 40 mm and the shape of the air-injecting holes was circular or elliptical. The developed injection duct systems were improved by obtaining a uniform mass flow rate at the air-injecting holes. A stenter prototype was fabricated with the developed injection duct system to confirm the numerical results. The developed injection duct system had better performance than the original system.

  19. MICRO-CHP System for Residential Applications

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Gerstmann

    2009-01-31

    This is the final report of progress under Phase I of a project to develop and commercialize a micro-CHP system for residential applications that provides electrical power, heating, and cooling for the home. This is the first phase of a three-phase effort in which the residential micro-CHP system will be designed (Phase I), developed and tested in the laboratory (Phase II); and further developed and field tested (Phase III). The project team consists of Advanced Mechanical Technology, Inc. (AMTI), responsible for system design and integration; Marathon Engine Systems, Inc. (MES), responsible for design of the engine-generator subsystem; AO Smith, responsible for design of the thermal storage and water heating subsystems; Trane, a business of American Standard Companies, responsible for design of the HVAC subsystem; and AirXchange, Inc., responsible for design of the mechanical ventilation and dehumidification subsystem.

  20. PIPEBOT: a mobile system for duct inspection

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Emanuel; Goncalves, Eder Mateus; Botelho, Silvia; Oliveira, Vinicius; Souto Junior, Humberto; Almeida, Renan de; Mello Junior, Claudio; Santos, Thiago [Universidade Federal do Rio Grande (FURG), RS (Brazil); Gulles, Roger [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil)

    2009-07-01

    In this paper, it is presented the development of an innovative and low-cost robotic mobile system to be employed in inspection of pipes. The system is composed of a robot with different sensors which permit to move inside pipes and detect faults as well as incipient faults. The robot is a semiautonomous one, i.e. it can navigate by human tele operation or autonomously one. The autonomous mode uses computer vision techniques and signals from position sensor of the robot to navigating and localizing it. It is showed the mechanical structure of the robot, the overall architecture of the system and preliminary results. (author)

  1. Dynamic management of integrated residential energy systems

    Science.gov (United States)

    Muratori, Matteo

    This study combines principles of energy systems engineering and statistics to develop integrated models of residential energy use in the United States, to include residential recharging of electric vehicles. These models can be used by government, policymakers, and the utility industry to provide answers and guidance regarding the future of the U.S. energy system. Currently, electric power generation must match the total demand at each instant, following seasonal patterns and instantaneous fluctuations. Thus, one of the biggest drivers of costs and capacity requirement is the electricity demand that occurs during peak periods. These peak periods require utility companies to maintain operational capacity that often is underutilized, outdated, expensive, and inefficient. In light of this, flattening the demand curve has long been recognized as an effective way of cutting the cost of producing electricity and increasing overall efficiency. The problem is exacerbated by expected widespread adoption of non-dispatchable renewable power generation. The intermittent nature of renewable resources and their non-dispatchability substantially limit the ability of electric power generation of adapting to the fluctuating demand. Smart grid technologies and demand response programs are proposed as a technical solution to make the electric power demand more flexible and able to adapt to power generation. Residential demand response programs offer different incentives and benefits to consumers in response to their flexibility in the timing of their electricity consumption. Understanding interactions between new and existing energy technologies, and policy impacts therein, is key to driving sustainable energy use and economic growth. Comprehensive and accurate models of the next-generation power system allow for understanding the effects of new energy technologies on the power system infrastructure, and can be used to guide policy, technology, and economic decisions. This

  2. Competitive solar heating systems for residential buildings

    DEFF Research Database (Denmark)

    Furbo, Simon; Thür, Alexander; Fiedler, Frank

    2005-01-01

    The paper describes the ongoing research project “Competitive solar heating systems for residential buildings”. The aim of the project is to develop competitive solar combisystems which are attractive to buyers. The solar combisystems must be attractive compared to traditional energy systems, both....... In Denmark and Norway the focus is on solar heating/natural gas systems, and in Sweden and Latvia the focus is on solar heating/pellet systems. Additionally, Lund Institute of Technology and University of Oslo are studying solar collectors of various types being integrated into the roof and facade...... of the building....

  3. Design of Residential Photovoltaic Systems

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Sera, Dezso; Mathe, Laszlo

    2017-01-01

    Renewable energy has become very important both worldwide and on the European market, mainly due to the decrease in the photovoltaic (PV) system cost (up to 75%) during the last decade. PV installations worldwide have reached 227 GW at the end of 2015 with a predicted extra 50 GW of new installat...

  4. Micro-CHP systems for residential applications

    International Nuclear Information System (INIS)

    Paepe, Michel de; D'Herdt, Peter; Mertens, David

    2006-01-01

    Micro-CHP systems are now emerging on the market. In this paper, a thorough analysis is made of the operational parameters of 3 types of micro-CHP systems for residential use. Two types of houses (detached and terraced) are compared with a two storey apartment. For each building type, the energy demands for electricity and heat are dynamically determined. Using these load profiles, several CHP systems are designed for each building type. Data were obtained for two commercially available gas engines, two Stirling engines and a fuel cell. Using a dynamic simulation, including start up times, these five system types are compared to the separate energy system of a natural gas boiler and buying electricity from the grid. All CHP systems, if well sized, result in a reduction of primary energy use, though different technologies have very different impacts. Gas engines seem to have the best performance. The economic analysis shows that fuel cells are still too expensive and that even the gas engines only have a small internal rate of return (<5%), and this only occurs in favourable economic circumstances. It can, therefore, be concluded that although the different technologies are technically mature, installation costs should at least be reduced by 50% before CHP systems become interesting for residential use. Condensing gas boilers, now very popular in new homes, prove to be economically more interesting and also have a modest effect on primary energy consumption

  5. Solar Energy Systems for Ohioan Residential Homeowners

    Science.gov (United States)

    Luckett, Rickey D.

    Dwindling nonrenewable energy resources and rising energy costs have forced the United States to develop alternative renewable energy sources. The United States' solar energy industry has seen an upsurge in recent years, and photovoltaic holds considerable promise as a renewable energy technology. The purpose of this case study was to explore homeowner's awareness of the benefits of solar energy. Disruptive-innovation theory was used to explore marketing strategies for conveying information to homeowners about access to new solar energy products and services. Twenty residential homeowners were interviewed face-to-face to explore (a) perceived benefits of solar energy in their county in Ohio, and (b) perceptions on the rationale behind the marketing strategy of solar energy systems sold for residential use. The study findings used inductive analyses and coding interpretation to explore the participants' responses that revealed 3 themes: the existence of environmental benefits for using solar energy systems, the expensive cost of equipment associated with government incentives, and the lack of marketing information that is available for consumer use. The implications for positive social change include the potential to enable corporate leaders, small business owners, and entrepreneurs to develop marketing strategies for renewable energy systems. These strategies may promote use of solar energy systems as a clean, renewable, and affordable alternative electricity energy source for the 21st century.

  6. Algorithm of dynamic regulation of a system of duct, for a high accuracy climatic system

    Science.gov (United States)

    Arbatskiy, A. A.; Afonina, G. N.; Glazov, V. S.

    2017-11-01

    Currently, major part of climatic system, are stationary in projected mode only. At the same time, many modern industrial sites, require constant or periodical changes in technological process. That is 80% of the time, the industrial site is not require ventilation system in projected mode and high precision of climatic parameters must maintain. While that not constantly is in use for climatic systems, which use in parallel for different rooms, we will be have a problem for balance of duct system. For this problem, was created the algorithm for quantity regulation, with minimal changes. Dynamic duct system: Developed of parallel control system of air balance, with high precision of climatic parameters. The Algorithm provide a permanent pressure in main duct, in different a flow of air. Therefore, the ending devises air flow have only one parameter for regulation - flaps open area. Precision of regulation increase and the climatic system provide high precision for temperature and humidity (0,5C for temperature, 5% for relative humidity). Result: The research has been made in CFD-system - PHOENICS. Results for velocity of air in duct, for pressure of air in duct for different operation mode, has been obtained. Equation for air valves positions, with different parameters for climate in room’s, has been obtained. Energy saving potential for dynamic duct system, for different types of a rooms, has been calculated.

  7. Competitive solar heating systems for residential buildings

    DEFF Research Database (Denmark)

    Furbo, Simon; Thür, Alexander; Fiedler, Frank

    2005-01-01

    .D. studies in Denmark, Sweden and Latvia, and a post-doc. study in Norway. Close cooperation between the researchers and the industry partners ensures that the results of the project can be utilized. By the end of the project the industry partners will be able to bring the developed systems onto the market...... from an economical and architectural point of view. The project includes education, research, development and demonstration. The project started in 2003 and will be finished by the end of 2006. The participants of the project, which is financed by Nordic Energy Research and the participants themselves......The paper describes the ongoing research project “Competitive solar heating systems for residential buildings”. The aim of the project is to develop competitive solar combisystems which are attractive to buyers. The solar combisystems must be attractive compared to traditional energy systems, both...

  8. Duct corrosion in the ventilating air conditioning system for Main Control Room

    International Nuclear Information System (INIS)

    Yamada, Kohei; Kobayashi, Takashi; Minami, Akiko; Fukuba, Kazushi

    2014-01-01

    Higashidori Nuclear Power Station, start-of-operation in December 2005, is a relatively new plant. We decided to get original data of air duct condition to determine maintenance policy of air duct, because planned maintenance of air duct has never been done and the corrosion of air duct has occurred in other plant. In January 2014, we found a corrosion-hole at the downstream of the inlet damper in the ventilating air conditioning system for Main Control Room (MCR). We supposed that the cause of rapid corrosion is related to the characteristic environment of this site. (author)

  9. Focus on Humanistic Values in Rural Livable Residential System

    Directory of Open Access Journals (Sweden)

    Sun Xiuli

    2015-01-01

    Full Text Available We consider the development of farmers as a goal of residential system using value rationality instead of farmer’s requirements which can be satisfied. Based upon the position and function of humanistic values in residential system, a rural housing system is built as a subjectivity and objectivity unity consisting of artifacts system, behavior system and concept system. Moreover, we introduce three coupling design strategies to rural livable residential system aiming to guide the current reconstruction of shabby buildings in rural areas.

  10. Residential heat pumps in the future Danish energy system

    DEFF Research Database (Denmark)

    Petrovic, Stefan; Karlsson, Kenneth Bernard

    2016-01-01

    Denmark is striving towards 100% renewable energy system in 2050. Residential heat pumps are expected to be a part of that system.We propose two novel approaches to improve the representation of residential heat pumps: Coefficients of performance (COPs) are modelled as dependent on air and ground...... temperature while installation of ground-source heat pumps is constrained by available ground area. In this study, TIMES-DK model is utilised to test the effects of improved modelling of residential heat pumps on the Danish energy system until 2050.The analysis of the Danish energy system was done...... for politically agreed targets which include: at least 50% of electricity consumption from wind power starting from 2020, fossil fuel free heat and power sector from 2035 and 100% renewable energy system starting from 2050. Residential heat pumps supply around 25% of total residential heating demand after 2035...

  11. Optimizing Hydronic System Performance in Residential Applications

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L.; Faakye, O.

    2013-10-01

    Even though new homes constructed with hydronic heat comprise only 3% of the market (US Census Bureau 2009), of the 115 million existing homes in the United States, almost 14 million of those homes (11%) are heated with steam or hot water systems according to 2009 US Census data. Therefore, improvements in hydronic system performance could result in significant energy savings in the US. When operating properly, the combination of a gas-fired condensing boiler with baseboard convectors and an indirect water heater is a viable option for high-efficiency residential space heating in cold climates. Based on previous research efforts, however, it is apparent that these types of systems are typically not designed and installed to achieve maximum efficiency. Furthermore, guidance on proper design and commissioning for heating contractors and energy consultants is hard to find and is not comprehensive. Through modeling and monitoring, CARB sought to determine the optimal combination(s) of components - pumps, high efficiency heat sources, plumbing configurations and controls - that result in the highest overall efficiency for a hydronic system when baseboard convectors are used as the heat emitter. The impact of variable-speed pumps on energy use and system performance was also investigated along with the effects of various control strategies and the introduction of thermal mass.

  12. Residential hot water distribution systems: Roundtablesession

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James D.; Klein, Gary; Springer, David; Howard, Bion D.

    2002-08-01

    Residential building practice currently ignores the lossesof energy and water caused by the poor design of hot water systems. Theselosses include: combustion and standby losses from water heaters, thewaste of water (and energy) while waiting for hot water to get to thepoint of use; the wasted heat as water cools down in the distributionsystem after a draw; heat losses from recirculation systems and thediscarded warmth of waste water as it runs down the drain. Severaltechnologies are available that save energy (and water) by reducing theselosses or by passively recovering heat from wastewater streams and othersources. Energy savings from some individual technologies are reported tobe as much as 30 percent. Savings calculations of prototype systemsincluding bundles of technologies have been reported above 50 percent.This roundtable session will describe the current practices, summarizethe results of past and ongoing studies, discuss ways to think about hotwater system efficiency, and point to areas of future study. We will alsorecommend further steps to reduce unnecessary losses from hot waterdistribution systems.

  13. Silver zeolite antimicrobial activity in aluminium heating, ventilation and air conditioning system ducts.

    Science.gov (United States)

    Rizzetto, R; Mansi, A; Panatto, D; Rizzitelli, E; Tinteri, C; Sasso, T; Gasparini, R; Crovari, P

    2008-03-01

    Air pollution in confined environments is a serious health problem, in that most people spend long periods indoors (in homes, offices, classrooms etc.). Some people (children, the elderly, heart disease patients, asthmatic or allergic subjects) are at greater risk because of their conditions of frailty. The growing use of air-conditioning systems in many public and private buildings aggravates this health risk, especially when these systems are not correctly installed or regularly serviced. The aim of our study was to verify the capacity of Ag+ ions to stop the growth of bacteria and moulds inside the ducts of Heating, Ventilation and Air Conditioning system ducts (HVAC) systems when these ducts were lined with active Ag+ ions zeolite-coated panels. A Y-shaped HVAC model with two branches was used; one branch was made of traditional galvanized iron, as was the whole system, while the other was lined with active Ag+ zeolite-coated polyurethane panels. During the test, samples of dust present inside both ducts were collected and seeded in liquid and solid media to detect bacteria and moulds. The presence of bacteria was also sought in the air emerging from the outlets of both ducts. Tests made on samples of particulate collected from the two different ducts revealed a lower total bacterial load in the samples collected from the Ag+ zeolite-coated duct than in the samples from the traditional Zn galvanized duct. In addition, the values of bacterial load found in the air emerging from the Ag+ ions zeolite-lined duct were 5 times lower than those found in the air from the traditional galvanized iron duct. The utilization of Ag+ zeolite-coated panels in air-conditioning systems could improve the quality of the emerging air in comparison with traditional installations in galvanized iron. This innovation could prove particularly advantageous in the event of accidents during the installation of air-conditioning systems or of contaminated aerosols coming from outside.

  14. Noise generation by ducted combustion systems. [resonant oscillations

    Science.gov (United States)

    Chiu, H. H.; Plett, E. G.; Summerfield, M.

    1973-01-01

    Analysis of the interaction between a zone of nonsteady combustion and its confining duct shows that resonant type oscillations occur with resulting noise intensities far greater than from corresponding unconfined flame zones. The blading action on the flow through the compressor and turbine of an engine generates discrete frequency noise which, it is found, is enhanced by the response of the combustion zone in between. Ducted combustor experiments verify the predicted resonant type noise, the amplitude and frequency of which are strongly influenced by the duct dimensions and end impedance. A convergent exit nozzle results in stronger internal resonant noise oscillations but also generates a higher jet velocity, with the attendant jet noise which exceeds noise from inside the duct at jet Mach numbers near unity.-

  15. Micro-CHP Systems for Residential Applications

    Energy Technology Data Exchange (ETDEWEB)

    Timothy DeValve; Benoit Olsommer

    2007-09-30

    Integrated micro-CHP (Cooling, Heating and Power) system solutions represent an opportunity to address all of the following requirements at once: conservation of scarce energy resources, moderation of pollutant release into our environment, and assured comfort for home-owners. The objective of this effort was to establish strategies for development, demonstration, and sustainable commercialization of cost-effective integrated CHP systems for residential applications. A unified approach to market and opportunity identification, technology assessment, specific system designs, adaptation to modular product platform component conceptual designs was employed. UTRC's recommendation to U.S. Department of Energy is to go ahead with the execution of the proposed product development and commercialization strategy plan under Phase II of this effort. Recent indicators show the emergence of micro-CHP. More than 12,000 micro-CHP systems have been sold worldwide so far, around 7,500 in 2004. Market projections predict a world-wide market growth over 35% per year. In 2004 the installations were mainly in Europe (73.5%) and in Japan (26.4%). The market in North-America is almost non-existent (0.1%). High energy consumption, high energy expenditure, large spark-spread (i.e., difference between electricity and fuel costs), big square footage, and high income are the key conditions for market acceptance. Today, these conditions are best found in the states of New York, Pennsylvania, New Jersey, Wisconsin, Illinois, Indiana, Michigan, Ohio, New England states. A multiple stage development plan is proposed to address risk mitigation. These stages include concept development and supplier engagement, component development, system integration, system demonstration, and field trials. A two stage commercialization strategy is suggested based on two product versions. The first version--a heat and power system named Micro-Cogen, provides the heat and essential electrical power to the

  16. FIELD EVALUATION OF IMPROVED METHODS FOR MEASURING THE AIR LEAKAGE OF DUCT SYSTEMS UNDER NORMAL OPERATING CONDITIONS IN 51 HOMES

    Energy Technology Data Exchange (ETDEWEB)

    Paul W. Francisco; Larry Palmiter; Erin Kruse; Bob Davis

    2003-10-18

    Duct leakage in forced-air distribution systems has been recognized for years as a major source of energy losses in residential buildings. Unfortunately, the distribution of leakage across homes is far from uniform, and measuring duct leakage under normal operating conditions has proven to be difficult. Recently, two new methods for estimating duct leakage at normal operating conditions have been devised. These are called the nulling test and the Delta-Q test. Small exploratory studies have been done to evaluate these tests, but previously no large-scale study on a broad variety of homes has been performed to determine the accuracy of these new methods in the field against an independent benchmark of leakage. This sort of study is important because it is difficult in a laboratory setting to replicate the range of leakage types found in real homes. This report presents the results of a study on 51 homes to evaluate these new methods relative to an independent benchmark and a method that is currently used. An evaluation of the benchmark procedure found that it worked very well for supply-side leakage measurements, but not as well on the return side. The nulling test was found to perform well, as long as wind effects were minimal. Unfortunately, the time and difficulty of setup can be prohibitive, and it is likely that this method will not be practical for general use by contractors except in homes with no return ducts. The Delta-Q test was found to have a bias resulting in overprediction of the leakage, which qualitatively confirms the results of previous laboratory, simulation, and small-scale field studies. On average the bias was only a few percent of the air handler flow, but in about 20% of the homes the bias was large. A primary flaw with the Delta-Q test is the assumption that the pressure between the ducts and the house remain constant during the test, as this assumption does not hold true. Various modifications to the Delta-Q method were evaluated as

  17. RESULTS OF A PILOT FIELD STUDY TO EVALUATE THE EFFECTIVENESS OF CLEANING RESIDENTIAL HEATING AND AIR-CONDITIONING SYSTEMS AND THE IMPACT ON INDOOR AIR QUALITY AND SYSTEM PERFORMANCE

    Science.gov (United States)

    The report discusses and gives results of a pilot field study to evaluate the effectiveness of air duct cleaning (ADC) as a source removal technique in residential heating and air-conditioning (HAC) systems and its impact on airborne particle, fiber, and bioaerosol concentrations...

  18. Structural organization and morphometric parameters in system of excretory ducts of human labial glands

    OpenAIRE

    Pilyugin A.V.; Sherstuk O.A.; Deynega T.F.; Ivanchenko N.I.

    2008-01-01

    With the aim of conformity and structural features revealing and space organization of excretory ducts of small salivary glands system of human being, the histology of wall of labial excretory ducts is studied, morphometry of their major size is carried out (external diameter, space, width of wall). In the system of excretory ducts of labial gland of human being, the change of size of their external and internal diameter is revealed, which is seen on the cutting and 3-D models such local shar...

  19. PEM - fuel cell system for residential applications

    Energy Technology Data Exchange (ETDEWEB)

    Britz, P. [Viessmann Werke GmbH and Co KG, 35107 Allendorf (Germany); Zartenar, N.

    2004-12-01

    Viessmann is developing a PEM fuel cell system for residential applications. The uncharged PEM fuel cell system has a 2 kW electrical and 3 kW thermal power output. The Viessmann Fuel Processor is characterized by a steam-reformer/burner combination in which the burner supplies the required heat to the steam reformer unit and the burner exhaust gas is used to heat water. Natural gas is used as fuel, which is fed into the reforming reactor after passing an integrated desulphurisation unit. The low temperature (600 C) fuel processor is designed on the basis of steam reforming technology. For carbon monoxide removal, a single shift reactor and selective methanisation is used with noble metal catalysts on monoliths. In the shift reactor, carbon monoxide is converted into hydrogen by the water gas shift reaction. The low level of carbon monoxide at the outlet of the shift reactor is further reduced, to approximately 20 ppm, downstream in the methanisation reactor, to meet PEM fuel cell requirements. Since both catalysts work at the same temperature (240 C), there is no requirement for an additional heat exchanger in the fuel processor. Start up time is less than 30 min. In addition, Viessmann has developed a 2 kW class PEFC stack, without humidification. Reformate and dry air are fed straight to the stack. Due to the dry operation, water produced by the cell reaction rapidly diffuses through the electrolyte membrane. This was achieved by optimising the MEA, the gas flow pattern and the operating conditions. The cathode is operated by an air blower. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  20. Measured Performance of a Varied Airflow Small-Diameter Duct System

    Energy Technology Data Exchange (ETDEWEB)

    Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-03-16

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  1. Measured Performance of a Varied Airflow Small-Diameter Duct System

    Energy Technology Data Exchange (ETDEWEB)

    Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-03-01

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  2. Building America Case Study: High-Velocity Small-Diameter Duct System, Pittsburgh, Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-01

    This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

  3. IMPLEMENTATION OF A TUNING SYSTEM FOR HELMHOLTZ RESONATOR ARRAYS IN A HVAC DUCT

    OpenAIRE

    寺尾, 道仁; Terao, Michihito; 関根, 秀久; Sekine, Hidehisa; 鈴木, 誠人; Suzuki, Masato

    2010-01-01

    Onsite tuning is mandatory to utilize Helmholtz resonators for HVAC ducts. However, no tuning device or general-use system is yet available, and engineers have thus been avoiding the use of such resonators. The objective of this study is to develop a tuning system for resonator arrays for HVAC ducts. We employed the cavity volume, resonator neck resistanceand neck open area as control parameters to tune the resonance frequency, resonancesharpness and sound dissipation factor, respectively. To...

  4. Endoscopic Ultrasonography-Guided Techniques for Accessing and Draining the Biliary System and the Pancreatic Duct.

    Science.gov (United States)

    Rimbaş, Mihai; Larghi, Alberto

    2017-10-01

    When endoscopic retrograde cholangiopancreatography (ERCP) fails to decompress the biliary system or the pancreatic duct, endoscopic ultrasonography (EUS)-guided biliary or pancreatic access and drainage can be used. Data show a high success rate and acceptable adverse event rate for EUS-guided biliary drainage. The outcomes of EUS-guided biliary drainage seem equivalent to percutaneous drainage and ERCP, whereas only retrospective studies are available for pancreatic duct drainage. In this article, revision of the technical and clinical status and the current evidence of interventional EUS-guided biliary and pancreatic duct access and drainage are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Development of a Smart Residential Fire Protection System

    Directory of Open Access Journals (Sweden)

    Juhwan Oh

    2013-01-01

    Full Text Available Embedded system is applied for the development of smart residential fire detection and extinguishing system. Wireless communication capability is integrated into various fire sensors and alarm devices. The system activates the fire alarm to warn occupants, executes emergency and rescue calls to remote residents and fire-fighting facility in an intelligent way. The effective location of extra-sprinklers within the space of interest for the fire extinguishing system is also investigated. Actual fire test suggests that the developed wireless system for the smart residential fire protection system is reliable in terms of sensors and their communication linkage.

  6. Improved Duct Systems Task Report with StageGate 2 Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Neil [Florida Solar Energy Center, Cocoa, FL (United States); Stroer, Dennis [Calcs-Plus, Venice, FL (United States)

    2007-12-31

    This report is about Building America Industrialized Housing Partnership's work with two industry partners, Davalier Homes and Southern Energy Homes, in constructing and evaluating prototype interior duct systems. Issues of energy performance, comfort, DAPIA approval, manufacturability and cost is addressed. A stage gate 2 analysis addresses the current status of project showing that there are still refinements needed to the process of incorporating all of the ducts within the air and thermal boundaries of the envelope.

  7. Residential space heating systems: energy conservation and economics

    Energy Technology Data Exchange (ETDEWEB)

    O' Neal, D.L.

    1979-01-01

    Annual energy use for residential space heating was 8.6 Quads in 1975. This accounted for over 50% of the energy used in the residential sector and 12% of energy used in the U.S. that year. Because residential space heating accounts for such a large share of energy use, improvements in new space heating systems could have significant long-term conservation effects. Several energy-saving design changes in residential space heating systems are examined to determine their energy conservation potential and cost effectiveness. Both changes in conventional and advanced systems are considered. Conventional design changes include options such as the flue damper, sealed combustion, electric ignition and improved heat exchangers. Some of the advanced designs include the gas heat pump, pulse combustion furnace, and dual speed compressor heat pump. The energy use and cost estimates are developed from current literature, heating and equipment manufacturers and dealers, and discussions with individuals doing research and testing on residential space heating equipment. Results indicate that implementation of conventional design changes can reduce energy use of representative gas, oil, and electric space heating systems by 26, 20, and 57%, respectively. These changes increase the capital cost of the systems by 27, 16, and 26%. Advanced gas and electric space heating systems can reduce energy use 45 and 67%, respectively. However, the advanced systems cost 80 and 35% more than representative gas and electric systems.

  8. A new bipolar feedback-controlled sealing system for closure of the cystic duct and artery.

    Science.gov (United States)

    Shamiyeh, A; Schrenk, P; Tulipan, L; Vattay, P; Bogner, S; Wayand, W

    2002-05-01

    Bile leaks are serious complications after laparoscopic cholecystectomy. The aim of this study was to evaluate the feasibility of closure of the cystic duct with a new feedback-controlled bipolar sealing system (LigaSure). Ten domestic pigs underwent open cholecystectomy with the cystic duct and artery dissected and sealed with the new bipolar sealing system (LigaSure). Four and 8 days postoperatively, 5 pigs each were sacrificed and the closure of the cystic duct was evaluated. The cystic stump and the common bile duct were excised for histological examination. None of the pigs had a bile leak or a biliary peritonitis. There were no signs of postoperative bleeding or inflammation in Calot's triangle. Histology showed total necrosis of the cystic duct in the first two pigs due to too much energy used. The remaining specimens showed a regularly scaling zone without necrosis in 7 cases, and in one case a partial necrosis in the mucosa only was found. Cystic artery and cystic duct closure with the new device may be an alternative to the clip. Further trials should evaluate the feasibility and safety of the new device in the clinical setting.

  9. Solar ejector refrigerant system in China’s residential buildings

    Directory of Open Access Journals (Sweden)

    Zheng Hui-Fan

    2014-01-01

    Full Text Available A simulation program describing the performance of solar ejector refrigerant system for air conditioning of China’s residential buildings was established. Hourly performance of the system under different operate conditions, the collector efficiency, coefficient of performance, cooling capacity and cooling load were analyzed. It is found that the collector efficiency and the overall coefficient of performance increase first and then decline, and it can be concluded that the application of solar ejector refrigerant system will have a better developmental prospect in China’s residential buildings.

  10. Modular Energy Management System Applicable to Residential Microgrids

    DEFF Research Database (Denmark)

    Hernández, Adriana Carolina Luna; Aldana, Nelson Leonardo Diaz; Graells, Moises

    2016-01-01

    In this paper, an energy management system is defined as a flexible architecture. This proposal can be applied to home and residential areas when they include generation units. The system has been integrated and tested in a grid-connected microgrid prototype, where optimal power generation profiles...

  11. A review of residential computer oriented energy control systems

    Energy Technology Data Exchange (ETDEWEB)

    North, Greg

    2000-07-01

    The purpose of this report is to bring together as much information on Residential Computer Oriented Energy Control Systems as possible within a single document. This report identifies the main elements of the system and is intended to provide many technical options for the design and implementation of various energy related services.

  12. Experimental Assessment of residential split type air-conditioning systems using alternative refrigerants to R-22 at high ambient temperatures

    International Nuclear Information System (INIS)

    Joudi, Khalid A.; Al-Amir, Qusay R.

    2014-01-01

    Highlights: • R290, R407C and R410A in residential split A/C units at high ambient. • 1 and 2 TR residential air conditioners with R22 alternatives at high ambient. • Residential split unit performance at ambients up to 55 °C with R22 alternatives. - Abstract: Steady state performance of residential air conditioning systems using R22 and alternatives R290, R407C, R410A, at high ambient temperatures, have been investigated experimentally. System performance parameters such as optimum refrigerant charge, coefficient of performance, cooling capacity, power consumption, pressure ratio, power per ton of refrigeration and TEWI environmental factor have been determined. All refrigerants were tested in the cooling mode operation under high ambient air temperatures, up to 55 °C, to determine their suitability. Two split type air conditioner of 1 and 2 TR capacities were used. A psychrometric test facility was constructed consisting of a conditioned cool compartment and an environmental duct serving the condenser. Air inside the conditioned compartment was maintained at 25 °C dry bulb and 19 °C wet bulb for all tests. In the environmental duct, the ambient air temperature was varied from 35 °C to 55 °C in 5 °C increments. The study showed that R290 is the better candidate to replace R22 under high ambient air temperatures. It has lower TEWI values and a better coefficient of performance than the other refrigerants tested. It is suitable as a drop-in refrigerant. R407C has the closest performance to R22, followed by R410A

  13. High Efficient Bidirectional Battery Converter for residential PV Systems

    DEFF Research Database (Denmark)

    Pham, Cam; Kerekes, Tamas; Teodorescu, Remus

    2012-01-01

    the power to balance it. High efficient bidirectional converter for the battery storage is required due high system cost and because the power is processed twice. A 1.5kW prototype is designed and built with CoolMOS and SiC diodes, >;95% efficiency has been obtained with 200 kHz hard switching.......Photovoltaic (PV) installation is suited for the residential environment and the generation pattern follows the distribution of residential power consumption in daylight hours. In the cases of unbalance between generation and demand, the Smart PV with its battery storage can absorb or inject...

  14. Community Design Parameters and the Performance of Residential Cogeneration Systems

    Directory of Open Access Journals (Sweden)

    Hazem Rashed-Ali

    2012-11-01

    Full Text Available The integration of cogeneration systems in residential and mixed-use communities has the potential of reducing their energy demand and harmful emissions and can thus play asignificant role in increasing their environmental sustainability. This study investigated the impact of selected planning and architectural design parameters on the environmental and economic performances of centralized cogeneration systems integrated into residential communities in U.S.cold climates. Parameters investigated include: 1 density, 2 use mix, 3 street configuration, 4 housing typology, 5 envelope and building systems’ efficiencies, and 6 passive solar energyutilization. The study integrated several simulation tools into a procedure to assess the impact of each design parameter on the cogeneration system performance. This assessment procedure included: developing a base-line model representing typical design characteristics of U.S. residential communities; assessing the cogeneration system’s performance within this model using three performance indicators: percentage of reduction in primary energy use, percentage of reduction in CO2 emissions; and internal rate of return; assessing the impact of each parameter on the system performance through developing 46 design variations of the base-line model representing potential changes in each parameter and calculating the three indicators for each variation; and finally, using a multi-attribute decision analysis methodology to evaluate the relative impact of each parameter on the cogeneration system performance. The study results show that planning parameters had a higher impact on the cogeneration system performance than architectural ones. Also, a significant correlation was found between design characteristics identified as favorable for the cogeneration system performance and those of sustainable residential communities. These include high densities, high use mix, interconnected street networks, and mixing of

  15. Ice Protection of Turbojet Engines by Inertia Separation of Water II : Single-offset-duct System

    Science.gov (United States)

    Von Glahn, Uwe

    1948-01-01

    Investigation of a single-offset-duct system designed to prevent entrance of water into a turbojet engine was conducted on a half-scale nacelle model. An investigation was made to determine ram-pressure recovery and radial velocity profiles at the compressor section and icing characteristics of such a duct system. At a design inlet velocity of 0.77, the maximum ram-pressure recovery attained with effective water-separating inlet was 77 percent, which is considerably less than attainable with a direct-ram inlet. Continuous heating of the accessory-housing surface would be required for inlets that have a small ice storage space.

  16. Residential cogeneration systems: review of the current technology

    International Nuclear Information System (INIS)

    Onovwiona, H.I.; Ugursal, V.I.

    2006-01-01

    There is a growing potential for the use of micro-cogeneration systems in the residential sector because they have the ability to produce both useful thermal energy and electricity from a single source of fuel such as oil or natural gas. In cogeneration systems, the efficiency of energy conversion increases to over 80% as compared to an average of 30-35% for conventional fossil fuel fired electricity generation systems. This increase in energy efficiency can result in lower costs and reduction in greenhouse gas emissions when compared to the conventional methods of generating heat and electricity separately. Cogeneration systems and equipment suitable for residential and small-scale commercial applications like hospitals, hotels or institutional buildings are available, and many new systems are under development. These products are used or aimed for meeting the electrical and thermal demands of a building for space and domestic hot water heating, and potentially, absorption cooling. The aim of this paper is to provide an up-to-date review of the various cogeneration technologies suitable for residential applications. The paper considers the various technologies available and under development for residential, i.e. single-family ( e ) and multi-family (10-30kW t ) applications, with focus on single-family applications. Technologies suitable for residential cogeneration systems include reciprocating internal combustion engine, micro-turbine, fuel cell, and reciprocating external combustion Stirling engine based cogeneration systems. The paper discusses the state of development and the performance, environmental benefits, and costs of these technologies. (author)

  17. Development of a Smart Residential Fire Protection System

    OpenAIRE

    Juhwan Oh; Zhongwei Jiang; Henry Panganiban

    2013-01-01

    Embedded system is applied for the development of smart residential fire detection and extinguishing system. Wireless communication capability is integrated into various fire sensors and alarm devices. The system activates the fire alarm to warn occupants, executes emergency and rescue calls to remote residents and fire-fighting facility in an intelligent way. The effective location of extra-sprinklers within the space of interest for the fire extinguishing system is also investigated. Actual...

  18. Application of Geographic Information System (GIS) in residential ...

    African Journals Online (AJOL)

    Application of Geographic Information System (GIS) in residential land capability index mapping of a developing country. A case study of Enugu ... The thematic layers were weighted on a scale of 0%-100% and 0-2 inclusive, using the criteria obtained from field work and laboratory investigation. The thematic layers were ...

  19. Morphology of the male reproductive duct system of Caiman crocodilus (Crocodylia, Alligatoridae).

    Science.gov (United States)

    Guerrero, Sandra M; Calderón, Martha L; de Pérez, Gloria R; Ramírez Pinilla, Martha Patricia

    2004-06-01

    The male reproductive duct system of Caiman crocodilus in different reproductive stages was studied using light and electron microscopy, to determine whether shared morphological features exist between Crocodylia and Aves, in concurrence with the Archosauria hypothesis. The sexual duct system of Caiman crocodilus is constituted of the rete testis, ductuli efferentes, ductuli epididymides, ductus epididymidis, and ductus deferens. The morphology and histochemical properties of these ducts suggest their involvement in seminal fluid production and/or its modification. Three types of non-ciliated cells were identified along the duct system. 1. The noncliated cells of the ductuli efferentes contain electron dense worm-like structures and coated vesicles, both related to absorptive processes, as has been suggested in Aves. 2. The non-ciliated cells of the ductuli epididymides have apical electron dense granules suggesting a secretory role, and 3. The non-ciliated cells of the ductus epididymidis and ductus deferens did not exhibit conspicuous storage of secretory material, but have a prominent rough endoplasmic reticulum content indicating active protein production. The occurrence of abundant secretory granules in the epithelial cells of the distal ductus deferens during non-reproductive stages suggests its participation in the removal of luminal debris when the reproductive season ends. Additional ducts were observed running along the ductus deferens; they shared morphological characteristics with the ductuli epididymides. The maximum diameter and therefore the greatest sperm accumulation of the excurrent ducts were observed during the initial testicular regression. The comparative analysis suggests that the male reproductive system of the Crocodylia exhibits structural characteristics nearer to those of Aves than to Lepidosauria, Testudines, and Mammalia, additional data that support an Aves and Crocodylia sister group relationship.

  20. A Comparison of Simulation Capabilities for Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Miller, William A [ORNL; Smith, Matt K [ORNL; Gu, Lixing [Florida Solar Energy Center (FSEC); New, Joshua Ryan [ORNL

    2014-11-01

    Typically, the cheapest way to install a central air conditioning system in residential buildings is to place the ductwork in the attic. Energy losses due to duct-attic interactions can be great, but current whole-house models are unable to capture the dynamic multi-mode physics of the interactions. The building industry is notoriously fragmented and unable to devote adequate research resources to solve this problem. Builders are going to continue to put ducts in the attic because floor space is too expensive to closet them within living space, and there are both construction and aesthetic issues with other approaches such as dropped ceilings. Thus, there is a substantial need to publicly document duct losses and the cost of energy used by ducts in attics so that practitioners, builders, homeowners and state and federal code officials can make informed decisions leading to changes in new construction and additional retrofit actions. Thus, the goal of this study is to conduct a comparison of AtticSim and EnergyPlus simulation algorithms to identify specific features for potential inclusion in EnergyPlus that would allow higher-fidelity modeling of HVAC operation and duct transport of conditioned air. It is anticipated that the resulting analysis from these simulation tools will inform energy decisions relating to the role of ducts in future building energy codes and standards.

  1. Technology Solutions Case Study: Raised Ceiling Interior Duct System, New Smyrna, Florida

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-09-01

    Builder S.E. Volusia County Habitat for Humanity (SEVHFH) was interested in constructing a home to the new U.S. Department of Energy (DOE) Zero Energy Ready Home standards. SEVHFH partners with DOE team Building America Partnership for Improved Residential Construction on Habitat for Humanity homes and routinely builds to ENERGY STAR V3.1. The only modification to the design needed to comply with the Zero Energy Ready Home criteria was the interior duct requirement. Unwilling to incur the added costs of a foam roof deck or wall heights that exceed 8 ft to accommodate a fur-down chase, SEVHFH opted to build a fur-up or raised ceiling chase. This case study describes the project.

  2. Waste removal systems and recycling participation in residential environments

    DEFF Research Database (Denmark)

    Thøgersen, John

    2002-01-01

    health are severely impaired (Pieters, 1989). More recently, resource waste and environmental hazards from waste have given rise to public and political concern as well, even when disposal systems are well managed. This concern has led to efforts to divert solid waste away from disposal and towards some......Systems for the removal of waste are important although often overlooked elements of any residential environment. It is an old insight that when these systems are ineffective (and this is globally and historically the rule rather than the exception), human living conditions and often even human...... form of recycling (Ackerman, 1997; Pieters, 1989). Therefore, residential environments in developed countries increasingly contain separate collection systems for that fraction of waste that can be recycled, and hence re-utilized, in the production of new goods. These collection systemsare in addition...

  3. Optimal Scheduling of Residential Microgrids Considering Virtual Energy Storage System

    Directory of Open Access Journals (Sweden)

    Weiliang Liu

    2018-04-01

    Full Text Available The increasingly complex residential microgrids (r-microgrid consisting of renewable generation, energy storage systems, and residential buildings require a more intelligent scheduling method. Firstly, aiming at the radiant floor heating/cooling system widely utilized in residential buildings, the mathematical relationship between the operative temperature and heating/cooling demand is established based on the equivalent thermodynamic parameters (ETP model, by which the thermal storage capacity is analyzed. Secondly, the radiant floor heating/cooling system is treated as virtual energy storage system (VESS, and an optimization model based on mixed-integer nonlinear programming (MINLP for r-microgrid scheduling is established which takes thermal comfort level and economy as the optimization objectives. Finally, the optimal scheduling results of two typical r-microgrids are analyzed. Case studies demonstrate that the proposed scheduling method can effectively employ the thermal storage capacity of radiant floor heating/cooling system, thus lowering the operating cost of the r-microgrid effectively while ensuring the thermal comfort level of users.

  4. Optimizing Hydronic System Performance in Residential Applications

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-10-01

    Even though new homes constructed with hydronic heat comprise only 3% of the market (US Census Bureau 2009), of the 115 million existing homes in the United States, almost 14 million of those homes (11%) are heated with steam or hot water systems according to 2009 US Census data. Therefore, improvements in hydronic system performance could result in significant energy savings in the US.

  5. Residential Photovoltaic/Thermal Energy System

    Science.gov (United States)

    Selcuk, M. K.

    1987-01-01

    Proposed system supplies house with both heat and electricity. Pair of reports describes concept for self-sufficient heating, cooling, and power-generating system for house. Panels on walls of house provide hot water, space heating, and heat to charge heat-storage system, and generate electricity for circulation pumps and fans. Roof panels generate electricity for household, operate heat pump for summer cooling, and provide supplementary winter heating via heat pump, using solar-cell cooling-fluid loop. Wall and roof panels used independently.

  6. Manufactured residential utility wall system (ResCore), overview

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, R. [Oak Ridge National Lab., TN (United States); Lundell, C.; Lau, T.M. [Auburn Univ., AL (United States)

    1997-05-01

    This paper provides an overview of the design and development of a manufactured residential utility wall system referred to as ResCore. ResCore is a self-contained, manufactured, residential utility wall that provides complete rough-in of utilities (power, gas, water, and phone) and other functions (exhaust, combustion make-up air, refrigerant lines, etc.) to serve the residential kitchen, bath, utility, and laundry rooms. Auburn University, Department of Industrial Design faculty and students, supported by a team of graduate student researchers and the project`s advisory team, developed the ResCore. The project was accomplished through a research subcontract from the US Department of Energy administered by the Oak Ridge National Laboratory. The ResCore wall system features a ``layered`` manufacturing technique that allows each major component group--structural, cold water, hot water, drain, gas, electric, etc.--to be built as a separate subassembly and easily brought together for final assembly. The two structural layers are reinforced with bridging that adds strength and also permits firm attachment of plumbing pipes and other systems to the wall frame.

  7. ECOLO-HOUSE in the snowy town. Study of the ventilating function what the heat collecting system of the air duct utilizing attic has; Yukiguni ECOLO-HOUSE. Kison kaoku no yaneura wo riyoshita duct shunetsu system

    Energy Technology Data Exchange (ETDEWEB)

    Umemiya, H.; Hirosawa, K. [Yamagata University, Yamagata (Japan)

    1996-10-27

    Described in this paper is an air duct heat collecting system, forming a link in the chain of natural energy utilization, in an attic of a house actually in presence. When a sirocco fan (blowing air from an indoor induction duct into the room) at the base of the highblocked floor is turned, air is sucked through an air intake under the eaves into a heat collecting duct (constructed utilizing the tilt roof and rafter). Heat from the roof warmed by sunshine is absorbed by air in the heat collecting duct and is fed to the highblocked floor structure through a heat collecting room and the induction duct. This system functions quite effectively as a ventilating device. Dew condensation on the walls and floor and musty smell have been eliminated. This system is good enough as a heater even on chilly days in early spring when there is sunshine. In the time zone with the sun shining, the system collects 4{times}10{sup 4}kJ per day, exhibiting a heat collecting efficiency of 4%. The heat collecting duct was analyzed for thermal environment, and the heat flux of the collected heat was determined as Qk(W/m{sup 2}=0.1{times}I-1.3{Theta}d-{Theta}a). In this equation, I is the quantity of insolation (W/m{sup 2}), {Theta}d is the temperature in the heat collecting duct, and {Theta}a is the free air temperature. 2 refs., 8 figs.

  8. Optimization scheduling in intelligent Energy Management System for the DC residential distribution system

    DEFF Research Database (Denmark)

    Yue, Jingpeng; Hu, Zhijian; Li, Chendan

    2017-01-01

    (EMS) with aid of the wireless communication and the smart meter is imperative in achieving ADR for DC residential community. This paper presents a framework of centralized management system integration and the key process of ADR in DC residential distribution system. The propose framework and methods......Smart DC residential distribution system(RDS) consisted by DC living homes will be a significant integral part in the future green transmission with demand flexibility. Meanwhile, the distributed generations will play an important role in the active demand response (DR). Energy Management System...

  9. Opinion leadership and willingness to pay for residential photovoltaic systems

    International Nuclear Information System (INIS)

    Yamamoto, Yoshihiro

    2015-01-01

    According to diffusion theory, opinion leaders play an important role in the diffusion of new technologies through interpersonal communication with potential adopters. This study investigates the role and utility of opinion leadership in photovoltaic (PV) system diffusion. Specifically, the study proposes, examines, and considers the implications of the hypothesis that there is a positive relationship between willingness to pay (WTP) for a PV system and opinion leadership on PV-system adoption. The investigation employed an internet-based questionnaire to assess the use of interpersonal communication in decision-making on adoption, to identify opinion leaders on adoption, and to characterize their WTP. The response pool consisted of 488 individuals who lived in a detached house, owned a residential PV system, and were responsible for making the decision to adopt the system. The results support the hypothesis. Considering that subsidization preferentially incentivizes households with greater WTP to adopt PV systems, this suggests that subsidization is more effective than purchases of PV power under feed-in tariffs in promoting the diffusion of residential PV systems through interpersonal communication. -- Highlights: •Interpersonal communication about the adoption of PV systems is analyzed. •A questionnaire survey is conducted. •Opinion leaders on PV-system adoption are identified. •A relationship is confirmed between willingness to pay and opinion leadership. •Subsidization is more essential than feed-in tariffs from this point of view

  10. Stochastic analysis of residential micro combined heat and power system

    International Nuclear Information System (INIS)

    Karami, H.; Sanjari, M.J.; Gooi, H.B.; Gharehpetian, G.B.; Guerrero, J.M.

    2017-01-01

    Highlights: • Applying colonial competitive algorithm to the problem of optimal dispatching. • Economic modeling of the residential integrated energy system. • Investigating differences of stand-alone and system-connected modes of fuel cell operation. • Considering uncertainty on the electrical load. • The effects of battery capacity and its efficiency on the system is investigated. - Abstract: In this paper the combined heat and power functionality of a fuel-cell in a residential hybrid energy system, including a battery, is studied. The demand uncertainties are modeled by investigating the stochastic load behavior by applying Monte Carlo simulation. The colonial competitive algorithm is adopted to the hybrid energy system scheduling problem and different energy resources are optimally scheduled to have optimal operating cost of hybrid energy system. In order to show the effectiveness of the colonial competitive algorithm, the results are compared with the results of the harmony search algorithm. The optimized scheduling of different energy resources is listed in an efficient look-up table for all time intervals. The effects of time of use and the battery efficiency and its size are investigated on the operating cost of the hybrid energy system. The results of this paper are expected to be used effectively in a real hybrid energy system.

  11. CFD Study of an Annular-Ducted Fan Lift System for VTOL Aircraft

    Directory of Open Access Journals (Sweden)

    Yun Jiang

    2015-09-01

    Full Text Available The present study aimed at assessing a novel annular-ducted fan lift system for VTOL aircraft through computational fluid dynamics (CFD simulations. The power and lift efficiency of the lift fan system in hover mode, the lift and drag in transition mode, the drag and flight speed of the aircraft in cruise mode and the pneumatic coupling of the tip turbine and jet exhaust were studied. The results show that the annular-ducted fan lift system can have higher lift efficiency compared to the rotor of the Apache helicopter; the smooth transition from vertical takeoff to cruise flight needs some extra forward thrust to overcome a low peak of drag; the aircraft with the lift fan system enclosed during cruise flight theoretically may fly faster than helicopters and tiltrotors based on aerodynamic drag prediction, due to the elimination of rotor drag and compressibility effects on the rotor blade tips; and pneumatic coupling of the tip turbine and jet exhaust of a 300 m/s velocity can provide enough moment to spin the lift fan. The CFD results provide insight for future experimental study of the annular-ducted lift fan VTOL aircraft.

  12. Evaluation of mixing downstream of tees in duct systems with respect to single point representative air sampling.

    Science.gov (United States)

    Kim, Taehong; O'Neal, Dennis L; Ortiz, Carlos

    2006-09-01

    Air duct systems in nuclear facilities must be monitored with continuous sampling in case of an accidental release of airborne radionuclides. The purpose of this work is to identify the air sampling locations where the velocity and contaminant concentrations fall below the 20% coefficient of variation required by the American National Standards Institute/Health Physics Society N13.1-1999. Experiments of velocity and tracer gas concentration were conducted on a generic "T" mixing system which included combinations of three sub ducts, one main duct, and air velocities from 0.5 to 2 m s (100 to 400 fpm). The experimental results suggest that turbulent mixing provides the accepted velocity coefficients of variation after 6 hydraulic diameters downstream of the T-junction. About 95% of the cases achieved coefficients of variation below 10% by 6 hydraulic diameters. However, above a velocity ratio (velocity in the sub duct/velocity in the main duct) of 2, velocity profiles were uniform in a shorter distance downstream of the T-junction as the velocity ratio went up. For the tracer gas concentration, the distance needed for the coefficients of variation to drop 20% decreased with increasing velocity ratio due to the sub duct airflow momentum. The results may apply to other duct systems with similar geometries and, ultimately, be a basis for selecting a proper sampling location under the requirements of single point representative sampling.

  13. Tracking the Sun IX: The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Darghouth, Naïm [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cates, Sarah [Exeter Associates, Columbia, MD (United States); DiSanti, Nicholas [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States)

    2016-08-16

    Now in its ninth edition, Lawrence Berkeley National Laboratory (LBNL)’s Tracking the Sun report series is dedicated to summarizing trends in the installed price of grid-connected solar photovoltaic (PV) systems in the United States. The present report focuses on residential and non-residential systems installed through year-end 2015, with preliminary trends for the first half of 2016. An accompanying LBNL report, Utility-Scale Solar, addresses trends in the utility-scale sector. This year’s report incorporates a number of important changes and enhancements from prior editions. Among those changes, LBNL has made available a public data file containing all non-confidential project-level data underlying the analysis in this report. Installed pricing trends presented within this report derive primarily from project-level data reported to state agencies and utilities that administer PV incentive programs, solar renewable energy credit (SREC) registration systems, or interconnection processes. Refer to the text box to the right for several key notes about these data. In total, data were collected and cleaned for more than 820,000 individual PV systems, representing 85% of U.S. residential and non-residential PV systems installed cumulatively through 2015 and 82% of systems installed in 2015. The analysis in this report is based on a subset of this sample, consisting of roughly 450,000 systems with available installed price data.

  14. High-Performance Ducts in Hot-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chitwood, Rick [National Renewable Energy Laboratory (NREL), Golden, CO (United States); German, Alea [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Weitzel, Elizabeth [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-30

    Duct thermal losses and air leakage have long been recognized as prime culprits in the degradation of heating, ventilating, and air-conditioning (HVAC) system efficiency. Both the U.S. Department of Energy’s Zero Energy Ready Home program and California’s proposed 2016 Title 24 Residential Energy Efficiency Standards require that ducts be installed within conditioned space or that other measures be taken to provide similar improvements in delivery effectiveness (DE). Pacific Gas & Electric Company commissioned a study to evaluate ducts in conditioned space and high-performance attics (HPAs) in support of the proposed codes and standards enhancements included in California’s 2016 Title 24 Residential Energy Efficiency Standards. The goal was to work with a select group of builders to design and install high-performance duct (HPD) systems, such as ducts in conditioned space (DCS), in one or more of their homes and to obtain test data to verify the improvement in DE compared to standard practice. Davis Energy Group (DEG) helped select the builders and led a team that provided information about HPD strategies to them. DEG also observed the construction process, completed testing, and collected cost data.

  15. Hybrid model predictive control of a residential HVAC system with on-site thermal energy generation and storage

    International Nuclear Information System (INIS)

    Fiorentini, Massimo; Wall, Josh; Ma, Zhenjun; Braslavsky, Julio H.; Cooper, Paul

    2017-01-01

    Highlights: • A comprehensive approach to managing thermal energy in residential buildings. • Solar-assisted HVAC system with on-site energy generation and storage. • Mixed logic-dynamical building model identified using experimental data. • Design and implementation of a logic-dynamical model predictive control strategy. • MPC applied to the Net-Zero Energy house winner of the Solar Decathlon China 2013. - Abstract: This paper describes the development, implementation and experimental investigation of a Hybrid Model Predictive Control (HMPC) strategy to control solar-assisted heating, ventilation and air-conditioning (HVAC) systems with on-site thermal energy generation and storage. A comprehensive approach to the thermal energy management of a residential building is presented to optimise the scheduling of the available thermal energy resources to meet a comfort objective. The system has a hybrid nature with both continuous variables and discrete, logic-driven operating modes. The proposed control strategy is organized in two hierarchical levels. At the high-level, an HMPC controller with a 24-h prediction horizon and a 1-h control step is used to select the operating mode of the HVAC system. At the low-level, each operating mode is optimised using a 1-h rolling prediction horizon with a 5-min control step. The proposed control strategy has been practically implemented on the Building Management and Control System (BMCS) of a Net Zero-Energy Solar Decathlon house. This house features a sophisticated HVAC system comprising of an air-based photovoltaic thermal (PVT) collector and a phase change material (PCM) thermal storage integrated with the air-handling unit (AHU) of a ducted reverse-cycle heat pump system. The simulation and experimental results demonstrated the high performance achievable using an HMPC approach to optimising complex multimode HVAC systems in residential buildings, illustrating efficient selection of the appropriate operating modes

  16. Induction of Sca-1 via activation of STAT3 system in the duct cells of the mouse submandibular gland by ligation of the main excretory duct.

    Science.gov (United States)

    Purwanti, Nunuk; Karabasil, Mileva Ratko; Matsuo, Shinsuke; Chen, Gang; Javkhlan, Purevjav; Azlina, Ahmad; Hasegawa, Takahiro; Yao, Chenjuan; Akamatsu, Tetsuya; Hosoi, Kazuo

    2011-11-01

    To examine the very initial step that takes place immediately after tissue injury and is linked to tissue regeneration, we employed the submandibular gland (SMG), which was injured by ligation of its main excretory duct (MED). Ligation of the MED of the SMG in mice induced the expression of Sca-1, a protein marker of hematopoietic stem cells. In the normal gland, a low level of Sca-1 was expressed, which was localized predominantly in the excretory duct cells. At 1 day after ligation, Sca-1 expression increased prominently in almost all of cells in the duct system, but not in the acinar cells. The level of Sca-1 mRNA had begun to increase at 6 h after ligation and continuously rose thereafter until it reached a plateau, which occurred ∼12 h after ligation. STAT3 phosphorylated at its tyrosine-705 (p-STAT3) in the ligated gland increased immediately after ligation, and it was localized in the nuclei of all duct cells. The results of an EMSA revealed the specific binding of a nuclear extract to the sequence of the γ-interferon activation site (GAS) present in the Sca-1 promoter and confirmed that such binding increased after ligation. Thus the present study suggests that STAT3, having been phosphorylated following MED ligation, was transferred to the nucleus, where it bound to the GAS element in the promoter of Sca-1 gene, resulting in promotion of Sca-1 gene expression. Actual prevention of STAT3 phosphorylation reduced the ligation-induced Sca-1 elevation.

  17. Tracking the Sun VIII. The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naïm R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Spears, Mike [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Buckley, Michael [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States); Grue, Nick [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-08-01

    Now in its eighth edition, Lawrence Berkeley National Laboratory (LBNL)’s Tracking the Sun report series is dedicated to summarizing trends in the installed price of grid-connected solar photovoltaic (PV) systems in the United States. The present report focuses on residential and nonresidential systems installed through year-end 2014, with preliminary trends for the first half of 2015. As noted in the text box below, this year’s report incorporates a number of important changes and enhancements. Among those changes, this year's report focuses solely on residential and nonresidential PV systems; data on utility-scale PV are reported in LBNL’s companion Utility-Scale Solar report series. Installed pricing trends presented within this report derive primarily from project-level data reported to state agencies and utilities that administer PV incentive programs, solar renewable energy credit (SREC) registration systems, or interconnection processes. In total, data were collected for roughly 400,000 individual PV systems, representing 81% of all U.S. residential and non-residential PV capacity installed through 2014 and 62% of capacity installed in 2014, though a smaller subset of this data were used in analysis.

  18. Manufactured Residential Utility Wall System (ResCore),

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Robert [Oak Ridge National Lab., TN (United States); Lundell, Clark; Lau, Tin Man [Auburn Univ., AL (United States)

    1997-12-31

    This paper describes the design and development of a manufactured residential utility wall system referred to as ResCore. ResCore is a self contained, manufactured, residential utility wall that provides complete rough-in of utilities (power, gas, water, and phone) and other functions (exhaust, combustion make-up air, refrigerant lines, etc.) to serve the kitchen, bath, utility, and laundry rooms. Auburn University, Department of Industrial Design faculty, students, supported by a team of graduate student researchers and the project`s advisory team, developed the ResCore. The project was accomplished through a research subcontract from the U.S. Department of Energy administered by the Oak Ridge National Laboratory. The ResCore wall system features a layered manufacturing technique that allows each major component group: structural, cold water, hot water, drain, gas, electric, etc. to be built as a separate subassembly and easily brought together for final assembly. The two structural layers are reinforced with bridging that adds strength and also permits firm attachment of plumbing pipes and other systems to the wall frame.

  19. Experimental analysis of an air-to-air heat recovery unit for balanced ventilation systems in residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Seara, Jose; Diz, Ruben; Uhia, Francisco J.; Dopazo, Alberto; Ferro, Jose M. [Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, University of Vigo, Campus Lagoas-Marcosende No. 9, 36310 Vigo (Spain)

    2011-01-15

    This paper deals with the experimental analysis of an air-to-air heat recovery unit equipped with a sensible polymer plate heat exchanger (PHE) for balanced ventilation systems in residential buildings. The PHE is arranged in parallel triangular ducts. An experimental facility was designed to reproduce the typical outdoor and exhaust air conditions with regard to temperature and humidity. The unit was tested under balanced operation conditions, as commonly used in practice. A set of tests was conducted under the reference operating conditions to evaluate the PHE performance. Afterwards, an experimental parametric analysis was conducted to investigate the influence of changing the operating conditions on the PHE performance. Experiments were carried out varying the inlet fresh air temperature, the exhaust air relative humidity and the air flow rate. The experimental results are shown and discussed in this paper. (author)

  20. The simulation of three-dimensional ray tracing and parameters optimization in DPL lens duct coupling system

    Science.gov (United States)

    Fan, Shuwei; Zhang, Yan; Shen, Yuting

    2010-06-01

    DPL coupling system was researched in this paper. First, the mathematic model of 3D and 2D light transmission in hollow duct was analyzed and compared. Then the 3D simulation software for all rays of the coupling system -lens duct was developed. The influence of various structural parameters of the hollow lens duct to the energy and the beam distribution were discussed with the help of developed software. The structural parameters such as the duct length, the lens radius, the size of the input and output ends were researched and were optimized to get higher efficiency and better beam distribution. Finally, the energy conversion efficiency and the beam spatial distribution of before and after optimization were compared. The results showed that the efficiency and the distribution of energy were well improved after the optimization.

  1. Stochastic analysis of residential micro combined heat and power system

    DEFF Research Database (Denmark)

    Karami, H.; Sanjari, M. J.; Gooi, H. B.

    2017-01-01

    In this paper the combined heat and power functionality of a fuel-cell in a residential hybrid energy system, including a battery, is studied. The demand uncertainties are modeled by investigating the stochastic load behavior by applying Monte Carlo simulation. The colonial competitive algorithm...... is adopted to the hybrid energy system scheduling problem and different energy resources are optimally scheduled to have optimal operating cost of hybrid energy system. In order to show the effectiveness of the colonial competitive algorithm, the results are compared with the results of the harmony search...... algorithm. The optimized scheduling of different energy resources is listed in an efficient look-up table for all time intervals. The effects of time of use and the battery efficiency and its size are investigated on the operating cost of the hybrid energy system. The results of this paper are expected...

  2. Propagation of sound waves in ducts

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2000-01-01

    Plane wave propagation in ducts with rigid walls, radiation from ducts, classical four-pole theory for composite duct systems, and three-dimentional waves in wave guides of various cross-sectional shape are described.......Plane wave propagation in ducts with rigid walls, radiation from ducts, classical four-pole theory for composite duct systems, and three-dimentional waves in wave guides of various cross-sectional shape are described....

  3. Neutronics shielding analysis of the last mirror-beam duct system for a laser fusion power reactor

    International Nuclear Information System (INIS)

    Ragheb, M.M.H.; Klein, A.C.

    1981-01-01

    A Monte Carlo three-dimensional neutronics analysis for the last mirror-beam duct system for the SOLASE conceptual laser-driven fusion power reactor design is presented. Detailed geometric configurations including the reactor cavity, the two last mirrors, and the three-section two-right-angle bends duct are modeled. Measurements are given of the dimensions and compositions of the reactor components, and of neutron scalar fluxes, spatial dependencies and neutron volumetric heating rates for the cases of aluminum or Boral as laser beam duct liners, and ordinary concrete or lead mortar as shield material. A three-dimensional modeling of laser-driven reactor penetrations is employed. The particle leakage is found to be excessively high for the configuration of the conceptual design considered and the advantages and disadvantages of various solutions, such as the use of Boral as a duct liner and the use of lead mortar instead of ordinary concrete as a shield material, are considered

  4. A Method for the Observation of the Primo Vascular System in the Thoracic Duct of a Rat

    Directory of Open Access Journals (Sweden)

    Sungha Kim

    2013-01-01

    Full Text Available Even though the primo vascular system (PVS has been observed in large caliber lymph vessels by several independent teams, the presence of the PVS in the thoracic duct has been reported by only one team, probably because reproducing the experiment is technically difficult. This brief report presents a new, relatively straightforward method, which is a simple modification of the previous method of dye injection into the lumbar node, to observe the PVS in a thoracic duct of a rat by injecting Alcian blue into the renal node. When this new method was applied to a rat, the branching of the primo vessel in the thoracic duct was clearly displayed. Thus, this new method is expected to extend the network of the PVS from abdominal lymph ducts to thoracic ones.

  5. Flow Simulation of Modified Duct System Wind Turbines Installed on Vehicle

    Science.gov (United States)

    Rosly, N.; Mohd, S.; Zulkafli, M. F.; Ghafir, M. F. Abdul; Shamsudin, S. S.; Muhammad, W. N. A. Wan

    2017-10-01

    This study investigates the characteristics of airflow with a flow guide installed and output power generated by wind turbine system being installed on a pickup truck. The wind turbine models were modelled by using SolidWorks 2015 software. In order to investigate the characteristic of air flow inside the wind turbine system, a computer simulation (by using ANSYS Fluent software) is used. There were few models being designed and simulated, one without the rotor installed and another two with rotor installed in the wind turbine system. Three velocities being used for the simulation which are 16.7 m/s (60 km/h), 25 m/s (90 km/h) and 33.33 m/s (120 km/h). The study proved that the flow guide did give an impact to the output power produced by the wind turbine system. The predicted result from this study is the velocity of the air inside the ducting system of the present model is better that reference model. Besides, the flow guide implemented in the ducting system gives a big impact on the characteristics of the air flow.

  6. Particle deposition in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Sippola, Mark Raymond [Univ. of California, Berkeley, CA (United States)

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 μm were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on the

  7. Ducted fan inlet/exit and rotor tip flow improvements for vertical lift systems

    Science.gov (United States)

    Akturk, Ali

    The current research utilized experimental and computational techniques in 5" and 22" diameter ducted fan test systems that have been custom designed and manufactured. Qualitative investigation of flow around the ducted fan was also performed using smoke flow visualizations. Quantitative measurements consisted of 2D and 3D velocity measurements using planar and Stereoscopic Particle Image Velocimetry (PIV and SPIV), high resolution total pressure measurements using Kiel total pressure probes and real time six-component force and torque measurements. The computational techniques used in this thesis included a recently developed radial equilibrium based rotor model(REBRM) and a three dimensional Reynolds-Averaged Navier Stokes (RANS) based CFD model. A radial equilibrium based rotor model (REBRM) developed by the author was effectively integrated into a three-dimensional RANS based computational system. The PIV measurements and computational flow predictions using (REBRM) near the fan inlet plane were in a good agreement at hover and forward flight conditions. The aerodynamic modifications resulting from the fan inlet flow distortions in forward flight regime were clearly captured in 2D PIV results. High resolution total pressure measurements at the downstream of the fan rotor showed that tip leakage, rotor hub separation, and passage flow related total pressure losses were dominant in hover condition. However, the losses were dramatically increased in forward flight because of inlet lip separation and distortion. A novel ducted fan inlet flow conditioning concept named "Double Ducted Fan" (DDF) was developed. The (DDF) concept has a potential to significantly improve the performance and controllability of VTOL UAVs and many other ducted fan based vertical lift systems. The new concept that will significantly reduce the inlet lip separation related performance penalties used a secondary stationary duct system to control "inlet lip separation" occurring especially at

  8. Endogenous retinoic acid activity in principal cells and intercalated cells of mouse collecting duct system.

    Directory of Open Access Journals (Sweden)

    Yuen Fei Wong

    2011-02-01

    Full Text Available Retinoic acid is the bioactive derivative of vitamin A, which plays an indispensible role in kidney development by activating retinoic acid receptors. Although the location, concentration and roles of endogenous retinoic acid in post-natal kidneys are poorly defined, there is accumulating evidence linking post-natal vitamin A deficiency to impaired renal concentrating and acidifying capacity associated with increased susceptibility to urolithiasis, renal inflammation and scarring. The aim of this study is to examine the presence and the detailed localization of endogenous retinoic acid activity in neonatal, young and adult mouse kidneys, to establish a fundamental ground for further research into potential target genes, as well as physiological and pathophysiological roles of endogenous retinoic acid in the post-natal kidneys.RARE-hsp68-lacZ transgenic mice were employed as a reporter for endogenous retinoic acid activity that was determined by X-gal assay and immunostaining of the reporter gene product, β-galactosidase. Double immunostaining was performed for β-galactosidase and markers of kidney tubules to localize retinoic acid activity. Distinct pattern of retinoic acid activity was observed in kidneys, which is higher in neonatal and 1- to 3-week-old mice than that in 5- and 8-week-old mice. The activity was present specifically in the principal cells and the intercalated cells of the collecting duct system in all age groups, but was absent from the glomeruli, proximal tubules, thin limbs of Henle's loop and distal tubules.Endogenous retinoic acid activity exists in principal cells and intercalated cells of the mouse collecting duct system after birth and persists into adulthood. This observation provides novel insights into potential roles for endogenous retinoic acid beyond nephrogenesis and warrants further studies to investigate target genes and functions of endogenous retinoic acid in the kidney after birth, particularly in the

  9. Possibility of hydrogen supply by shared residential fuel cell systems for fuel cell vehicles

    Directory of Open Access Journals (Sweden)

    Ono Yusuke

    2017-01-01

    Full Text Available Residential polymer electrolyte fuel cells cogeneration systems (residential PEFC systems produce hydrogen from city gas by internal gas-reformer, and generate electricity, the hot water at the same time. From the viewpoint of the operation, it is known that residential PEFC systems do not continuously work but stop for long time, because the systems generate enough hot water for short operation time. In other words, currently residential PEFC systems are dominated by the amount of hot water demand. This study focuses on the idle time of residential PEFC systems. Since their gas-reformers are free, the systems have potential to produce hydrogen during the partial load operations. The authors expect that residential PEFC systems can take a role to supply hydrogen for fuel cell vehicles (FCVs before hydrogen fueling stations are distributed enough. From this perspective, the objective of this study is to evaluate the hydrogen production potential of residential PEFC systems. A residential PEFC system was modeled by the mixed integer linear programming to optimize the operation including hydrogen supply for FCV. The objective function represents annual system cost to be minimized with the constraints of energy balance. It should be noted that the partial load characteristics of the gas-reformer and the fuel cell stack are taken into account to derive the optimal operation. The model was employed to estimate the possible amount of hydrogen supply by a residential PEFC system. The results indicated that the system could satisfy at least hydrogen demand for transportation of 8000 km which is as far as the average annual mileage of a passenger car in Japan. Furthermore, hydrogen production by sharing a residential PEFC system with two households is more effective to reduce primary energy consumption with hydrogen supply for FCV than the case of introducing PEFC in each household.

  10. Solar Heating and Cooling of Residential Buildings: Sizing, Installation and Operation of Systems.

    Science.gov (United States)

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    This training course and a companion course titled "Design of Systems for Solar Heating and Cooling of Residential Buildings," are designed to train home designers and builders in the fundamentals of solar hydronic and air systems for space heating and cooling and domestic hot water heating for residential buildings. Each course, organized in 22…

  11. Review of Residential Low-Load HVAC Systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Scott A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thornton, Brian A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Widder, Sarah H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-01

    In support of the U.S. Department of Energy’s (DOE’s) Building America Program, Pacific Northwest National Laboratory (PNNL) conducted an investigation to inventory commercially available HVAC technologies that are being installed in low-load homes. The first step in this investigation was to conduct a review of published literature to identify low-load HVAC technologies available in the United States and abroad, and document the findings of existing case studies that have evaluated the performance of the identified technologies. This report presents the findings of the literature review, identifies gaps in the literature or technical understanding that must be addressed before low-load HVAC technologies can be fully evaluated, and introduces PNNL’s planned research and analysis for this project to address identified gaps and potential future work on residential low-load HVAC systems.

  12. Energy Savings and Peak Demand Reduction of a SEER 21 Heat Pump vs. a SEER 13 Heat Pump with Attic and Indoor Duct Systems

    Energy Technology Data Exchange (ETDEWEB)

    Cummings, J.; Withers, C.

    2014-03-01

    This report describes results of experiments that were conducted in an unoccupied 1600 square foot house--the Manufactured Housing (MH Lab) at the Florida Solar Energy Center (FSEC)--to evaluate the delivered performance as well as the relative performance of a SEER 21 variable capacity heat pump versus a SEER 13 heat pump. The performance was evaluated with two different duct systems: a standard attic duct system and an indoor duct system located in a dropped-ceiling space.

  13. Controls on the quality of harvested rainwater in residential systems

    Science.gov (United States)

    Sojka, S. L.; Phung, D.; Hollingsworth, C.

    2014-12-01

    Rainwater harvesting systems, in which runoff from roofs is collected and used for irrigation, toilets and other purposes, present a viable solution to limited freshwater supplies and excess stormwater runoff. However, a lack of data on the quality of harvested rainwater hinders adoption of rainwater harvesting systems and makes development of rainwater harvesting regulations difficult. We conducted monthly surveys of 6 existing residential rainwater harvesting systems ranging in age from 1 to 11 years measuring pH, temperature, dissolved oxygen, total suspended solids, dissolved organic carbon, and coliform bacteria. We also examined a subset of the samples for iron, lead, mercury and arsenic. Many of the systems routinely met the water quality requirements for non-potable use without additional treatment, which is often required by regulations. In addition, while previous studies have shown that roof runoff contains heavy metals, the water in all systems showed very low or undetectable levels of metal contamination. Coliform bacteria concentration ranged from 20 to greater than 1400 CFU's per 100 mL and correlated with total suspended solids, which ranged from 2 - 7 mg l-1. The relationship between suspended solids and bacteria population was confirmed in a controlled experiment on the impact of filtering the rainwater before storage. Filtration decreased total suspended solids and total coliforms and increased dissolved oxygen concentration. This project provides insight into the effects of system design and a baseline assessment of the quality of harvested rainwater in existing systems.

  14. Design and Implementation of an Innovative Residential PV System

    Science.gov (United States)

    Najm, Elie Michel

    This work focuses on the design and implementation of an innovative residential PV system. In chapter one, after an introduction related to the rapid growth of solar systems' installations, the most commonly used state of the art solar power electronics' configurations are discussed, which leads to introducing the proposed DC/DC parallel configuration. The advantages and disadvantages of each of the power electronics' configurations are deliberated. The scope of work in the power electronics is defined in this chapter to be related to the panel side DC/DC converter. System integration and mechanical proposals are also within the scope of work and are discussed in later chapters. Operation principle of a novel low cost PV converter is proposed in chapter 2. The proposal is based on an innovative, simplified analog implementation of a master/slave methodology resulting in an efficient, soft-switched interleaved variable frequency flybacks, operating in the boundary conduction mode (BCM). The scheme concept and circuit configuration, operation principle and theoretical waveforms, design equations, and design considerations are presented. Furthermore, design examples are also given, illustrating the significance of the newly derived frequency equation for flybacks operating in BCM. In chapters 3, 4, and 5, the design implementation and optimization of the novel DC/DC converter illustrated in chapter 2 are discussed. In chapter 3, a detailed variable frequency BCM flyback design model leading to optimizing the component selections and transformer design, detailed in chapter 4, is presented. Furthermore, in chapter 4, the method enabling the use of lower voltage rating switching devices is also discussed. In chapter 5, circuitry related to Start-UP, drive for the main switching devices, zero-voltage-switching (ZVS) as well as turn OFF soft switching and interleaving control are fully detailed. The experimental results of the proposed DC/DC converter are presented in

  15. Measured Air Distribution Effectiveness for Residential Mechanical Ventilation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Sherman, Max H.; Walker, Iain S.

    2008-05-01

    The purpose of ventilation is dilute or remove indoor contaminants that an occupant is exposed to. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. Most US homes have central HVAC systems, which tend to mix the air thus the indoor conditions between zones. Different types of ventilation systems will provide different amounts of exposure depending on the effectiveness of their air distribution systems and the location of sources and occupants. This paper will report on field measurements using a unique multi-tracer measurement system that has the capacity to measure not only the flow of outdoor air to each zone, but zone-to-zone transport. The paper will derive seven different metrics for the evaluation of air distribution. Measured data from two homes with different levels of natural infiltration will be used to evaluate these metrics for three different ASHRAE Standard 62.2 compliant ventilation systems. Such information can be used to determine the effectiveness of different systems so that appropriate adjustments can be made in residential ventilation standards such as ASHRAE Standard 62.2.

  16. Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max H.; Walker, Iain S.

    2011-04-01

    Existing ventilation standards, including American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Standard 62.2, specify continuous operation of a defined mechanical ventilation system to provide minimum ventilation, with time-based intermittent operation as an option. This requirement ignores several factors and concerns including: other equipment such as household exhaust fans that might incidentally provide ventilation, negative impacts of ventilation when outdoor pollutant levels are high, the importance of minimizing energy use particularly during times of peak electricity demand, and how the energy used to condition air as part of ventilation system operation changes with outdoor conditions. Dynamic control of ventilation systems can provide ventilation equivalent to or better than what is required by standards while minimizing energy costs and can also add value by shifting load during peak times and reducing intake of outdoor air contaminants. This article describes the logic that enables dynamic control of whole-house ventilation systems to meet the intent of ventilation standards and demonstrates the dynamic ventilation system control concept through simulations and field tests of the Residential Integrated Ventilation-Energy Controller (RIVEC).

  17. Transition duct system with arcuate ceramic liner for delivering hot-temperature gases in a combustion turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, David J.

    2017-11-07

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include an arcuate connecting segment (36). An arcuate ceramic liner (60) may be inwardly disposed onto a metal outer shell (38) along the arcuate connecting segment of the exit piece. Structural arrangements are provided to securely attach the ceramic liner in the presence of substantial flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liner can be readily removed and replaced as needed.

  18. A Hierarchical Transactive Energy Management System for Energy Sharing in Residential Microgrids

    Directory of Open Access Journals (Sweden)

    Most Nahida Akter

    2017-12-01

    Full Text Available This paper presents an analytical framework to develop a hierarchical energy management system (EMS for energy sharing among neighbouring households in residential microgrids. The houses in residential microgrids are categorized into three different types, traditional, proactive and enthusiastic, based on the inclusion of solar photovoltaic (PV systems and battery energy storage systems (BESSs. Each of these three houses has an individual EMS, which is defined as the primary EMS. Two other EMSs (secondary and tertiary are also considered in the proposed hierarchical energy management framework for the purpose of effective energy sharing. The intelligences of each EMS are presented in this paper for the purpose of energy sharing in a residential microgrid along with the priorities. The effectiveness of the proposed hierarchical framework is evaluated on a residential microgrid in Australia. The analytical results clearly reflect that the proposed scheme effectively and efficiently shares the energy among neighbouring houses in a residential microgrid.

  19. Evaluation of a high-temperature burner-duct-recuperator system

    Science.gov (United States)

    1990-07-01

    The U.S. Department of Energy's (DOE) Office of Industrial Technologies (OIT) sponsors research and development (R and D) to improve the energy efficiency of American industry and to provide for fuel flexibility. OIT has funded a multiyear R and D project by the Babcock and Wilcox Company (B and W) to design, fabricate, field test, and evaluate a high-temperature burner-duct-recuperator (HTBDR) system. This ceramic-based recuperator system recovers waste heat from the corrosive, high-temperature (2170 F) flue gas stream of a steel soaking pit to preheat combustion air to as high as 1700 F. The preheated air is supplied to a high-temperature burner. The B and W R and D program, which is now complete, involved several activities, including selecting and evaluating ceramic materials, designing the system, and developing and evaluating the prototype. In addition, a full-scale unit was tested at a B and W steel soaking pit. The full-scale system consisted of a modular single-stage ceramic recuperator, a conventional two-pass metallic recuperator, a high-temperature burner, fans, insulated ducting, and associated controls and instrumentation. The metallic recuperator preheated combustion air to about 750 F before it passed to the ceramic module. This technical case study describes the DOE/B and W recuperator project and highlights the field tests of the full-scale recuperator system. The document makes results of field tests and data analysis available to other researchers and private industry. It discusses project status, summarizes field tests, and reviews the potential effects the technology will have on energy use and system economics.

  20. Incentive Pass-through for Residential Solar Systems in California

    Energy Technology Data Exchange (ETDEWEB)

    Dong, C. G. [Univ. of Texas, Austin, TX (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rai, Varun [Univ. of Texas, Austin, TX (United States)

    2014-10-01

    The deployment of solar photovoltaic (PV) systems has grown rapidly over the last decade, partly because of various government incentives. In the United States, among the largest and longest-running incentives have been those established in California. Building on past research, this report addresses the still-unanswered question: to what degree have the direct PV incentives in California been passed through from installers to consumers? This report helps address this question by carefully examining the residential PV market in California (excluding a certain class of third-party-owned PV systems) and applying both a structural-modeling approach and a reduced-form regression analysis to estimate the incentive pass-through rate. The results suggest an average pass-through rate of direct incentives of nearly 100%, though with regional differences among California counties. While these results could have multiple explanations, they suggest a relatively competitive market and well-functioning subsidy program. Further analysis is required to determine whether similar results broadly apply to other states, to other customer segments, to all third-party-owned PV systems, or to all forms of financial incentives for solar (considering not only direct state subsidies, but also utility electric bill savings and federal tax incentives).

  1. Advanced Controls for Residential Whole-House Ventilation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-01

    Whole-house ventilation systems are becoming commonplace in new construction, remodeling/renovation, and weatherization projects, driven by combinations of specific requirements for indoor air quality (IAQ), health and compliance with standards, such as ASHRAE 62.2. Ventilation systems incur an energy penalty on the home via fan power used to drive the airflow, and the additional space-conditioning load associated with heating or cooling the ventilation air. Finding a balance between IAQ and energy use is important if homes are to be adequately ventilated while not increasing the energy burden. This study used computer simulations to examine RIVEC the Residential Integrated Ventilation Controller - a prototype ventilation controller that aims to deliver whole-house ventilation rates that comply with ventilation standards, for the minimum use of energy. Four different whole-house ventilation systems were simulated, both with and without RIVEC, so that the energy and IAQ results could be compared. Simulations were conducted for 13 US climate zones, three house designs, and three envelope leakage values. The results showed that the RIVEC controller could typically return ventilation energy savings greater than 40percent without compromising long-term chronic or short-term acute exposures to relevant indoor contaminants. Critical and average peak power loads were also reduced as a consequence of using RIVEC.

  2. Economic Optimization of Component Sizing for Residential Battery Storage Systems

    Directory of Open Access Journals (Sweden)

    Holger C. Hesse

    2017-06-01

    Full Text Available Battery energy storage systems (BESS coupled with rooftop-mounted residential photovoltaic (PV generation, designated as PV-BESS, draw increasing attention and market penetration as more and more such systems become available. The manifold BESS deployed to date rely on a variety of different battery technologies, show a great variation of battery size, and power electronics dimensioning. However, given today’s high investment costs of BESS, a well-matched design and adequate sizing of the storage systems are prerequisites to allow profitability for the end-user. The economic viability of a PV-BESS depends also on the battery operation, storage technology, and aging of the system. In this paper, a general method for comprehensive PV-BESS techno-economic analysis and optimization is presented and applied to the state-of-art PV-BESS to determine its optimal parameters. Using a linear optimization method, a cost-optimal sizing of the battery and power electronics is derived based on solar energy availability and local demand. At the same time, the power flow optimization reveals the best storage operation patterns considering a trade-off between energy purchase, feed-in remuneration, and battery aging. Using up to date technology-specific aging information and the investment cost of battery and inverter systems, three mature battery chemistries are compared; a lead-acid (PbA system and two lithium-ion systems, one with lithium-iron-phosphate (LFP and another with lithium-nickel-manganese-cobalt (NMC cathode. The results show that different storage technology and component sizing provide the best economic performances, depending on the scenario of load demand and PV generation.

  3. Design and optimization of zero-energy-consumption based solar energy residential building systems

    Science.gov (United States)

    Zheng, D. L.; Yu, L. J.; Tan, H. W.

    2017-11-01

    Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

  4. Whole house particle removal and clean air delivery rates for in-duct and portable ventilation systems.

    Science.gov (United States)

    Macintosh, David L; Myatt, Theodore A; Ludwig, Jerry F; Baker, Brian J; Suh, Helen H; Spengler, John D

    2008-11-01

    A novel method for determining whole house particle removal and clean air delivery rates attributable to central and portable ventilation/air cleaning systems is described. The method is used to characterize total and air-cleaner-specific particle removal rates during operation of four in-duct air cleaners and two portable air-cleaning devices in a fully instrumented test home. Operation of in-duct and portable air cleaners typically increased particle removal rates over the baseline rates determined in the absence of operating a central fan or an indoor air cleaner. Removal rates of 0.3- to 0.5-microm particles ranged from 1.5 hr(-1) during operation of an in-duct, 5-in. pleated media filter to 7.2 hr(-1) for an in-duct electrostatic air cleaner in comparison to a baseline rate of 0 hr(-1) when the air handler was operating without a filter. Removal rates for total particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) mass concentrations were 0.5 hr(-1) under baseline conditions, 0.5 hr(-1) during operation of three portable ionic air cleaners, 1 hr(-1) for an in-duct 1-in. media filter, 2.4 hr(-1) for a single high-efficiency particle arrestance (HEPA) portable air cleaner, 4.6 hr(-1) for an in-duct 5-in. media filter, 4.7 hr(-1) during operation of five portable HEPA filters, 6.1 hr(-1) for a conventional in-duct electronic air cleaner, and 7.5 hr(-1) for a high efficiency in-duct electrostatic air cleaner. Corresponding whole house clean air delivery rates for PM2.5 attributable to the air cleaner independent of losses within the central ventilation system ranged from 2 m3/min for the conventional media filter to 32 m3/min for the high efficiency in-duct electrostatic device. Except for the portable ionic air cleaner, the devices considered here increased particle removal indoors over baseline deposition rates.

  5. Taylor dispersion and the optimization of residential geothermal heating systems

    Science.gov (United States)

    Townsend, Jessica; Ortan, Alexandra; Quenneville-Belair, Vincent; Tilley, B. S.

    2008-11-01

    Residential geothermal heating systems have been developed over the past few decades as an alternative to fossil-fuel based heating. These systems consist of tubing (2 cm radius, 1 km in length) buried below the ground surface through which a coolant flows. Tube length has a direct correlation to installation cost. The temperature of this fluid rises as it flows through the tubing, and the energy from this temperature difference is utilized to heat the residence. As a first model, we consider a single tube of fluid encased in an infinite medium of soil, with the goal to find the minimum length over which temperature variations occur. Through lubrication theory, we derive an evolution equation for the local soil temperature near the tubing. We find that Taylor dispersion of heat in the fluid and thermostat frequency dictate the minimum tubing length needed for successful operation in an insulated subsystem. Next, matched asymptotics is used to incorporate far-field temperature variations. Comparison of our model with experiment is presented.

  6. Tracking the Sun 10: The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); LaCommare, Kristina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DiSanti, Nicholas [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States)

    2017-09-21

    Berkeley Lab’s Tracking the Sun report series is dedicated to summarizing trends in the installed price of grid-connected, residential and non-residential systems solar photovoltaic (PV) systems in the United States. The present report, the tenth edition in the series, focuses on systems installed through year-end 2016, with preliminary data for the first half of 2017. The report provides an overview of both long-term and more-recent trends, highlighting key drivers for installed price declines over different time horizons. The report also extensively characterizes the widespread variability in system pricing, comparing installed prices across states, market segments, installers, and various system and technology characteristics. The trends described in this report derive from project-level data collected by state agencies and utilities that administer PV incentive programs, solar renewable energy credit (SREC) registration systems, or interconnection processes. In total, data for this report were compiled and cleaned for more than 1.1 million individual PV systems, though the analysis in the report is based on a subset of that sample, consisting of roughly 630,000 systems with available installed price data. The full underlying dataset of project-level data (excluding any confidential information) is available in a public data file, for use by other researchers and analysts.

  7. Secondary air systems for improved residential wood stove combustion

    Energy Technology Data Exchange (ETDEWEB)

    Poirot, R.L.; Sanborn, C.R.

    1982-12-21

    Three wood burning stoves were modified by the addition of preheated secondary air systems to keep burn volatile gases given off during the initial stage of combustion. This report describes the modifications and the performance of the stoves after modification. Stoves tested during the year's study included a Jotul 118, a Garrison IV and a Hearthstone I. After modification, total particulate emissions decreased in the three stoves by 56%, 69% and 4%, respectively. Flue gas CO/sub 2/ (a by-product of combustion and an indicator of the completeness of combustion) increased by 15%, 15% and 17%, respectively. Temperatures in the secondary combustion zones increased by 17%, 50% and 6%. On the basis of these measurements, other internal temperatures and visual observations, we believe the modifications significantly increased the combustion efficiencies of the Jotul and the Garrison. No improvement was discerned in the Hearthstone's performance (possibly due to unrealistic burn rate compared to firebox size). The design concepts developed, refined and tested under this year's study should be readily applicable to the majority of residential wood stoves on the market.

  8. Selection and Exergy Analysis of Fuel Cell System to Meet all Energy Needs of Residential Buildings

    OpenAIRE

    G.R. Ashari; N.Hedayat; S. Shalbaf; E.Hajidavalloo

    2011-01-01

    In this paper a polymer electrolyte membrane (PEM) fuel cell power system including burner, steam reformer, heat exchanger and water heater has been considered to meet the electrical, heating, cooling and domestic hot water loads of residential building which in Tehran. The system uses natural gas as fuel and works in CHP mode. Design and operating conditions of a PEM fuel cell system is considered in this study. The energy requirements of residential building and the num...

  9. Acoustic modeling of fan noise generation and scattering in a modular duct system

    NARCIS (Netherlands)

    Nijhof, M.J.J.; Beltman, Marco; Wijnant, Ysbrand H.; de Boer, Andries

    2005-01-01

    Fan noise is an important noise source in computers. The noise spectrum of fans contains tonal noise, found at the so-called Blade Passing Frequency (BPF) and its higher harmonics, that plays an important role in the perceived sound quality. An acoustic resonator integrated in the duct of an in-duct

  10. Intelligent demand side management of residential building energy systems

    Science.gov (United States)

    Sinha, Maruti N.

    Advent of modern sensing technologies, data processing capabilities and rising cost of energy are driving the implementation of intelligent systems in buildings and houses which constitute 41% of total energy consumption. The primary motivation has been to provide a framework for demand-side management and to improve overall reliability. The entire formulation is to be implemented on NILM (Non-Intrusive Load Monitoring System), a smart meter. This is going to play a vital role in the future of demand side management. Utilities have started deploying smart meters throughout the world which will essentially help to establish communication between utility and consumers. This research is focused on investigation of a suitable thermal model of residential house, building up control system and developing diagnostic and energy usage forecast tool. The present work has considered measurement based approach to pursue. Identification of building thermal parameters is the very first step towards developing performance measurement and controls. The proposed identification technique is PEM (Prediction Error Method) based, discrete state-space model. The two different models have been devised. First model is focused toward energy usage forecast and diagnostics. Here one of the novel idea has been investigated which takes integral of thermal capacity to identify thermal model of house. The purpose of second identification is to build up a model for control strategy. The controller should be able to take into account the weather forecast information, deal with the operating point constraints and at the same time minimize the energy consumption. To design an optimal controller, MPC (Model Predictive Control) scheme has been implemented instead of present thermostatic/hysteretic control. This is a receding horizon approach. Capability of the proposed schemes has also been investigated.

  11. Integration of plug-in hybrid electric vehicles (PHEV) with grid connected residential photovoltaic energy systems

    Science.gov (United States)

    Nagarajan, Adarsh; Shireen, Wajiha

    2013-06-01

    This paper proposes an approach for integrating Plug-In Hybrid Electric Vehicles (PHEV) to an existing residential photovoltaic system, to control and optimize the power consumption of residential load. Control involves determining the source from which residential load will be catered, where as optimization of power flow reduces the stress on the grid. The system built to achieve the goal is a combination of the existing residential photovoltaic system, PHEV, Power Conditioning Unit (PCU), and a controller. The PCU involves two DC-DC Boost Converters and an inverter. This paper emphasizes on developing the controller logic and its implementation in order to accommodate the flexibility and benefits of the proposed integrated system. The proposed controller logic has been simulated using MATLAB SIMULINK and further implemented using Digital Signal Processor (DSP) microcontroller, TMS320F28035, from Texas Instruments

  12. POSSIBLE ROLE OF INDOOR RADON REDUCTION SYSTEMS IN BACK-DRAFTING RESIDENTIAL COMBUSTION APPLIANCES

    Science.gov (United States)

    The article gives results of a computational sensitivity analysis conducted to identify conditions under which residential active soil depressurization (ASD) systems for indoor radon reduction might contribute to or create back-drafting of natural draft combustion appliances. Par...

  13. Integrated Urban System and Energy Consumption Model: Residential Buildings

    Directory of Open Access Journals (Sweden)

    Rocco Papa

    2014-05-01

    Full Text Available This paper describes a segment of research conducted within the project PON 04a2_E Smart Energy Master for the energetic government of the territory conducted by the Department of Civil, Architectural and Environment Engineering, University of Naples "Federico II".  In particular, this article is part of the study carried out for the definition of the comprehension/interpretation model that correlates buildings, city’s activities and users’ behaviour in order to promote energy savings. In detail, this segment of the research wants to define the residential variables to be used in the model. For this purpose a knowledge framework at international level has been defined, to estimate the energy requirements of residential buildings and the identification of a set of parameters, whose variation has a significant influence on the energy consumption of residential buildings.

  14. Residential valuation systems in the United Arab Emirates

    OpenAIRE

    Ebraheim Lahbash; Simon Huston

    2015-01-01

    Since 1996, real estate development has transformed the United Arab Emirates (UAE) into a regional trade and logistics hub. Between January 2003 and December 2010 Dubai Residential Property Price Index (DRPPI) rose from 100 to a heady 240 in 2008 and then dropped back to 156.19 by 2010. The value of two bedroom apartments in the iconic 'Burj Khalif, the world's tallest building, rose to $3,811 and fell back down to $762 per per square foot. During the 2008 property collapse, residential price...

  15. Development of residential PEFC cogeneration systems at Osaka Gas

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Osamu; Echigo, Mitsuaki; Shinke, Norihisa; Tabata, Takeshi [Osaka Gas Ltd., Kyoto (Japan)

    2001-07-01

    The outline of residential PEFC cogeneration system development at Osaka Gas is described in this presentation. The developments of CO preferential oxidation catalyst, fuel processor, and the evaluation study of MEA are explained in detail. Osaka Gas has developed CO preferential oxidation catalyst, which can reduce the concentration of CO in the reformed gas below 1 ppm at the O{sub 2}/CO of 1.5. The durability of the catalyst for more than 10,000 hours has also been confirmed. A fuel processor in which desulfurization, steam reforming, CO shift conversion and CO removal reactors are integrated has also been developed. Catalysts, the durability of which have been verified for more than 50,000 hours, were employed in the reactors for desulfurization, steam reforming and CO shift conversion, and newly developed catalyst mentioned above was employed for the CO preferential oxidation reactor. The initial performance of the fuel processor has been established. The thermal efficiency of 77% has been accomplished under the condition of S/C: 2.5, O{sub 2}/CO: 1.5 and the utilization rate of fuel at the cell stack (Uf): 80%. And further, the durability for more than 1000 hours was confirmed. Durability of MEAs manufactured by Japan Gore-Tex and 3M have been evaluated. Small degradation rate of ca. 2 mV 11,000 h was found at the current density of 300 mAcm{sup -2}, Uf of 60% and the temperature of 70 {sup o}C. The tolerance of anode for CO has also been investigated, and had confirmed that the decline of cell performance could be negligible when the concentration of CO was less than 10 ppm. (author)

  16. Sensorless PV Array Diagnostic Method for Residential PV Systems

    DEFF Research Database (Denmark)

    Sera, Dezso; Spataru, Sergiu; Mathe, Laszlo

    2011-01-01

    This work proposes a temperature and irradiance sensorless diagnostic method suitable for small residential PV installations, focusing on detection of partial shadows. The method works by detection of failures in crystalline silicone PV arrays by concomitant monitoring of some of their key...

  17. Particle loading rates for HVAC filters, heat exchangers, and ducts.

    Science.gov (United States)

    Waring, M S; Siegel, J A

    2008-06-01

    The rate at which airborne particulate matter deposits onto heating, ventilation, and air-conditioning (HVAC) components is important from both indoor air quality (IAQ) and energy perspectives. This modeling study predicts size-resolved particle mass loading rates for residential and commercial filters, heat exchangers (i.e. coils), and supply and return ducts. A parametric analysis evaluated the impact of different outdoor particle distributions, indoor emission sources, HVAC airflows, filtration efficiencies, coils, and duct system complexities. The median predicted residential and commercial loading rates were 2.97 and 130 g/m(2) month for the filter loading rates, 0.756 and 4.35 g/m(2) month for the coil loading rates, 0.0051 and 1.00 g/month for the supply duct loading rates, and 0.262 g/month for the commercial return duct loading rates. Loading rates are more dependent on outdoor particle distributions, indoor sources, HVAC operation strategy, and filtration than other considered parameters. The results presented herein, once validated, can be used to estimate filter changing and coil cleaning schedules, energy implications of filter and coil loading, and IAQ impacts associated with deposited particles. The results in this paper suggest important factors that lead to particle deposition on HVAC components in residential and commercial buildings. This knowledge informs the development and comparison of control strategies to limit particle deposition. The predicted mass loading rates allow for the assessment of pressure drop and indoor air quality consequences that result from particle mass loading onto HVAC system components.

  18. Characterization of pipes, drain lines, and ducts using the pipe explorer system

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, C.D.; Kendrick, D.T.; Cramer, E.

    1997-05-01

    As DOE dismantles its nuclear processing facilities, site managers must employ the best means of disposing or remediating hundreds of miles of potentially contaminated piping and duct work. Their interiors are difficult to access, and in many cases even the exteriors are inaccessible. Without adequate characterization, it must be assumed that the piping is contaminated, and the disposal cost of buried drain lines can be on the order of $1,200/ft and is often unnecessary as residual contamination levels often are below free release criteria. This paper describes the program to develop a solution to the problem of characterizing radioactive contamination in pipes. The technical approach and results of using the Pipe Explorer {trademark} system are presented. The heart of the system is SEA`s pressurized inverting membrane adapted to transport radiation detectors and other tools into pipes. It offers many benefits over other pipe inspection approaches. It has video and beta/gamma detection capabilities, and the need for alpha detection has been addressed through the development of the Alpha Explorer{trademark}. These systems have been used during various stages of decontamination and decommissioning of DOE sites, including the ANL CP-5 reactor D&D. Future improvements and extensions of their capabilities are discussed.

  19. Magnetic resonance sialography for investigating major salivary gland duct system after intensity-modulated radiotherapy of nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Ou Dan; He Xiayun; Zhang Yunyan

    2013-01-01

    We investigated the value of magnetic resonance sialography for evaluating xerostomia induced by intensity-modulated radiotherapy for nasopharyngeal carcinoma. Fourteen patients with nasopharyngeal carcinoma were treated with intensity-modulated radiotherapy. Salivary function was assessed by magnetic resonance sialography and subjective evaluation criteria pre-treatment, 1 week and 1 year post-radiotherapy. A magnetic resonance sialography categorical scoring system was used to compare the visibility of salivary ducts. The average mean dose was 38.93 Gy to the parotid glands and 59.34 Gy to the submandibular glands. Before radiotherapy, the visibility scores of both the parotid and submandibular ducts increased after secretion stimulation. The scores decreased and the response to stimulation was attenuated 1 week post-radiotherapy. For most of the parotid ducts, the visibility score improved at 1 year post-radiotherapy both at rest and under stimulation, but not for the submandibular ducts. With a median follow-up of 12.3 months, 8/12 patients had grade 1 xerostomia and 4/12 had grade 2 xerostomia. Magnetic resonance sialography allows non-invasive evaluation of radiation-induced ductal changes in the major salivary glands and enables reliable prediction of radiation-induced xerostomia. (author)

  20. Comparison of the Standard of Air Leakage in Current Metal Duct Systems in the World

    Science.gov (United States)

    Di, Yuhui; Wang, Jiqian; Feng, Lu; Li, Xingwu; Hu, Chunlin; Shi, Junshe; Xu, Qingsong; Qiao, Leilei

    2018-01-01

    Based on the requirements of air leakage of metal ducts in Chinese design standards, technical measures and construction standards, this paper compares the development history, the classification of air pressure levels and the air tightness levels of air leakage standards of current Chinese and international metal ducts, sums up the differences, finds shortage by investigating the design and construction status and access to information, and makes recommendations, hoping to help the majority of engineering and technical personnel.

  1. Duct having oscillatory side wall

    Energy Technology Data Exchange (ETDEWEB)

    Sprouse, Kenneth M.

    2018-04-03

    A pump system includes a particulate consolidator pump that has a pump outlet. A duct is coupled to the pump outlet. The duct has a wall that is coupled with an oscillator. The oscillator is operable to oscillate the wall at a controlled frequency. The controlled frequency is selected with respect to breaking static bridging of particulate in the duct due, at least in part, to consolidation of the particulate from a downstream check valve.

  2. Transition duct system with metal liners for delivering hot-temperature gases in a combustion turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, David J.

    2017-04-11

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include a straight path segment (26) and an arcuate connecting segment (36). A respective straight metal liner (92) and an arcuate metal liner (94) may be each inwardly disposed onto a metal outer shell (38) along the straight path segment and the arcuate connecting segment (36) of the exit piece. Structural arrangements are provided to securely attach the respective liners in the presence of substantial flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liners can be readily removed and replaced as needed.

  3. Transition duct system with straight ceramic liner for delivering hot-temperature gases in a combustion turbine engine

    Science.gov (United States)

    Wiebe, David J.

    2017-05-16

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include a straight path segment (26) for receiving a gas flow from a respective combustor. A straight ceramic liner (40) may be inwardly disposed onto a metal outer shell (38) along the straight path segment of the exit piece. Structural arrangements are provided to securely attach the ceramic liner in the presence of substantial flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liner can be readily removed and replaced as needed.

  4. Measure Guideline. Sealing and Insulating Ducts in Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, R. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Puttagunta, S. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2011-12-01

    This document begins with a discussion on potential cost and performance benefits of duct sealing and insulating. It continues with a review of typical duct materials and components and the overall procedures for assessing and improving the duct system.

  5. Measure Guideline: Sealing and Insulating of Ducts in Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, R.; Puttagunta, S.

    2011-12-01

    This document begins with a discussion on potential cost and performance benefits of duct sealing and insulating. It continues with a review of typical duct materials and components and the overall procedures for assessing and improving the duct system.

  6. Cystic fibrosis transmembrane conductance regulator protein expression in the male excretory duct system during development.

    Science.gov (United States)

    Marcorelles, Pascale; Gillet, Danièle; Friocourt, Gaëlle; Ledé, Françoise; Samaison, Laura; Huguen, Geneviève; Ferec, Claude

    2012-03-01

    Sterility due to bilateral destruction in utero or in early infancy resulting in congenital absence of the vas deferens is the rule in male patients with cystic fibrosis. To understand the developmental pattern of this anomaly, the microscopic morphology of the male excretory system was analyzed during development and the expression of the cystic fibrosis transmembrane conductance regulator protein was explored by immunohistochemistry. We observed that cystic fibrosis fetuses had no excretory ducts agenesis or obstruction until 22 weeks of gestation. However, a focal inflammatory pattern and mucinous plugs in the oldest cystic fibrosis case suggested a disruptive mechanism. Immunolabeling of cytoplasmic epithelial cystic fibrosis transmembrane conductance regulator protein was demonstrated in all cystic fibrosis and control cases with a similar pattern of expression of the protein between age-matched controls and cystic fibrosis cases. At midgestation, an apical intensification appeared in both cystic fibrosis and control cases and was stable during the remainder of fetal life. No gradient of intensity could be detected between the different segments of the excretory tract. These findings are different from those reported in adults. The absence of any morphologic anomaly until 22 weeks of gestation, the focal destruction of the epithelial structures during the second trimester, and the chronological pattern of expression of cystic fibrosis transmembrane conductance regulator are of interest for a better understanding of the pathophysiology of this disease. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

    Science.gov (United States)

    Savchenko, Olena; Zhelykh, Vasyl; Voll, Hendrik

    2017-12-01

    The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

  8. Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

    Directory of Open Access Journals (Sweden)

    Savchenko Olena

    2017-12-01

    Full Text Available The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

  9. Real-Time Energy Management System for a Hybrid AC/DC Residential Microgrid

    DEFF Research Database (Denmark)

    Diaz, Enrique Rodriguez; Palacios-Garcia, Emilio J.; Anvari-Moghaddam, Amjad

    2017-01-01

    This paper proposes real-time Energy Management System (EMS) for a residential hybrid ac/dc microgrid. The residential microgrid is organized in two different distribution systems. A dc distribution bus which interconnect the renewable energy sources (RES), energy storage systems (ESS......) and the building’s common facilities; while the apartments are supplied by an ac distribution system connected to the grid. This architecture avoids any modifications in the electrical installation that supplies energy to the apartments. A pure dc voltage supply is not yet a feasible approach for residential...... setup. The results shown how the operational costs of the system are effectively decreased by 28%, even with non-accurate estimation of the RES generation or building parameters....

  10. Error analysis for duct leakage tests in ASHRAE standard 152P

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.W.

    1997-06-01

    This report presents an analysis of random uncertainties in the two methods of testing for duct leakage in Standard 152P of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). The test method is titled Standard Method of Test for Determining Steady-State and Seasonal Efficiency of Residential Thermal Distribution Systems. Equations have been derived for the uncertainties in duct leakage for given levels of uncertainty in the measured quantities used as inputs to the calculations. Tables of allowed errors in each of these independent variables, consistent with fixed criteria of overall allowed error, have been developed.

  11. Modeling and simulation of a residential micro-CHP system based on HT-PEMFC technology

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2009-01-01

    Combined-heat-and-power (CHP) technology is a well known and proved method to produce simultaneously power and heat at high efficiencies. This can be further improved by the introduction of a novel micro-CHP residential system based on High Temperature-Proton Exchange Membrane Fuel Cell (HT-PEMFC......). The HT-PEMFC (based on PBI-membrane technology) operates at temperatures near 200oC, and this can be an ideal match for cogeneration residential systems. The proposed system provides electric power, hot water, and space heating for a typical household (1-5 kWe, 5-10 kWth). The micro-CHP system...

  12. Integrated Strip Foundation Systems for Small Residential Buildings

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2010-01-01

    A prefabricated lightweight element was designed for a strip foundation that was used on site as the bases of two small residential buildings, in this case single-family houses; one was built with a double-brick exterior wall separated by mineral fiber insulation and the other was built with a wood......-stud exterior wall with mineral fiber insulation. The element was placed on a stable surface underneath the top soil layer, just 0.25 m below the finished ground surface. The prefabricated element was designed to comply with the requirements of a high energy-efficient performance stipulated in the new Danish...

  13. An Analysis on Optimization of Living and Fire Water Supply Systems of Small High-Rise Residential Blocks

    Science.gov (United States)

    Yuan, Min

    2017-11-01

    With the rapid growth of our population, the demand for housing quality of urban residents has been gradually raised. Due to the shortage of traditional multi-storey residential and high-rise residential, it is difficult to achieve a balance between quality and quantity of housing. As a result, a new type of residential building, small high-rise residential building, came into being. The so-called small high-rise residential generally refers to buildings of 7 to 11 layers, including unit buildings and tower buildings. In view of the problems existing in the water supply system of the small high-rise residential blocks, this paper presents a new system, namely a combined system of living and fire water supply. This system can be, according to the available pressure of municipal pipeline network, divided into three types, and has been optimized in order to fully utilize the municipal pipeline network pressure

  14. Preliminary design package for residential heating/cooling system: Rankine air conditioner redesign

    Science.gov (United States)

    1978-01-01

    A summary of the preliminary redesign and development of a marketable single family heating and cooling system is presented. The interim design and schedule status of the residential (3-ton) redesign, problem areas and solutions, and the definition of plans for future design and development activities were discussed. The proposed system for a single-family residential heating and cooling system is a single-loop, solar-assisted, hydronic-to-warm-air heating subsystem with solar-assisted domestic water heating and a Rankine-driven expansion air-conditioning subsystem.

  15. Preliminary design package for residential heating/cooling system--Rankine air conditioner redesign

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    This report contains a summary of the preliminary redesign and development of a marketable single-family heating and cooling system. The objectives discussed are the interim design and schedule status of the Residential (3-ton) redesign, problem areas and solutions, and the definition of plans for future design and development activities. The proposed system for a single-family residential heating and cooling system is a single-loop, solar-assisted, hydronic-to-warm-air heating subsystem with solar-assisted domestic water heating and a Rankine-driven expansion air-conditioning subsystem.

  16. System approach to prevent common bile duct injury and enhance performance of laparoscopic cholecystectomy.

    Science.gov (United States)

    Lien, Heng-Hui; Huang, Chi-Cheng; Liu, Jung-Sen; Shi, Min-Yean; Chen, Der-Fang; Wang, Nai-Yuan; Tai, Feng-Chuan; Huang, Ching-Shui

    2007-06-01

    Experience collected from 5200 cases of laparoscopic cholecystectomy (LC) and 29 patients (6 ours, 23 referred) with major common bile duct (CBD) injury during LC in our institute between December 1990 and July 2004 was reported to demonstrate that the system approach we applied in performing LC prevents CBD injury and enhances surgical performance. Each case of CBD injury was meticulously analyzed to identify causative factors. We developed preventive strategies focusing on 4 dimensions: patient, environment, procedure, and operator. Surgical performance was then evaluated to demonstrate improvements. Incidence of CBD injury was calculated for early and latter halves of the series to compare 5 parameters of surgical performance: patient selection, operation time, indwelling drainage tube, surgeon, and conversion rate. Results of accident analysis demonstrated that CBD injury followed definite mechanisms; several warning signs appearing before and during injury were identified and classified. According to these results, we designed strategies to prevent injury, including: setting up patient-selection program, controlling surgical environment, developing error-proof procedures, and constructing training programs. Incidence of CBD injury in the whole series was 0.12% (6/5200), 0.27% in early half (6/2224), and zero (0/2967) in latter half. Attending doctors had significantly shorter operation times in latter period for both elective and emergent LC. Rate of using drainage tubes for elective surgery by attending doctors was significantly decreased in latter period. Operation time for elective surgery by residents was similar in both early and latter periods. However, residents in latter period had longer operation times (around 23 min long, Pperformance. Consistent use of systems approach promises continuing quality improvement. We believe our working model will help perform safer LC and also benefit other medical disciplines.

  17. A novel classification system to address financial impact and referral decisions for bile duct injury in laparoscopic cholecystectomy.

    Science.gov (United States)

    Cannon, Robert M; Brock, Guy; Buell, Joseph F

    2011-01-01

    Purpose. The study was undertaken to evaluate a novel classification system developed to estimate financial cost of bile duct injury (BDI) and to aid in decision making for referral. Study Design. A retrospective review of patients referred for BDI was performed. Grade I injuries involve the duct of Luschka or accessory right hepatic ducts, grade II includes all other biliary injuries, and grade III includes all vasculobiliary injuries. Groups were compared using standard statistical methods. Results. There were 14 grade I, 74 grade II, and 20 grade III injuries. There was a significant difference in the cost and mortality of grade I ($12,457, 0%), grade II ($46,481, 1.4%), and grade III ($69,368, 15%, P = 0.002 and P = 0.030, resp.) injuries. Grade II and III injuries were significantly more likely to require surgical repair (OR 27.7, P < 0.001). Conclusion. We have presented a simple classification system that is able to accurately predict cost and need for surgical repair.

  18. Patent arterial duct

    Directory of Open Access Journals (Sweden)

    Martin Robin P

    2009-07-01

    pulmonary overcirculation secondary to a left-to-right shunt must be excluded. Coronary, systemic and pulmonary arteriovenous fistula, peripheral pulmonary stenosis and ventricular septal defect with aortic regurgitation and collateral vessels must be differentiated from PAD on echocardiogram. In preterm infants with symptomatic heart failure secondary to PAD, treatment may be achieved by surgical ligation or with medical therapy blocking prostaglandin synthesis (indomethacin or ibuprofen. Transcatheter closure of the duct is usually indicated in older children. PAD in preterm and low birth weight infants is associated with significant co-morbidity and mortality due to haemodynamic instability. Asymptomatic patients with a small duct have a normal vital prognosis but have a lifetime risk of endocarditis. Patients with moderate-to-large ducts with significant haemodynamic alterations may develop irreversible changes to pulmonary vascularity and pulmonary hypertension.

  19. Second life battery energy storage system for residential demand response service

    DEFF Research Database (Denmark)

    Saez-de-Ibarra, Andoni; Martinez-Laserna, Egoitz; Koch-Ciobotaru, Cosmin

    2015-01-01

    The integration of renewable energies and the usage of battery energy storage systems (BESS) into the residential buildings opens the possibility for minimizing the electricity bill for the end-user. This paper proposes the use of batteries that have already been aged while powering electric...... vehicles, during their main first life application, for providing residential demand response service. The paper considers the decayed characteristics of these batteries and optimizes the rating of such a second life battery energy storage system (SLBESS) for maximizing the economic benefits of the user...

  20. Economic evaluation of small wind turbines and hybrid systems for residential use

    Directory of Open Access Journals (Sweden)

    Predescu Mihail

    2016-01-01

    Full Text Available Renewable electricity generating systems are gaining ground in residential sector for the purpose of diminishing the electricity bills or to reaching some degree of energy independence. The decision to invest in small wind turbines or hybrid energy generation technologies should be based on an economic estimation of money invested in such systems. Levelized Cost of Energy (LCOE calculation for local technologies of choice for residential energy generation is a very meaningful figure for deciding whether the investment can bring financial satisfaction and for selecting which type of technology is the best suited for a specific location.

  1. Potency of energy saving and emission reduction from lighting system in residential sector of Indonesia

    Science.gov (United States)

    Ambarita, H.

    2018-03-01

    The Government of Indonesia (GoI) has a strong commitment to the target of decreasing energy intensity and reducing Greenhouse gas emissions. One of the significant solutions to reach the target is increasing energy efficiency in the lighting system in the residential sector. The objective of this paper is twofold, to estimate the potency of energy saving and emission reduction from lighting in the residential sector. Literature related to the lighting system in Indonesia has been reviewed to provide sufficient data for the estimation of the energy saving and emission reduction. The results show that the in the year 2016, a total of 95.33 TWh of nationally produced electricity is used in the residential sector. This is equal to 44% of total produced electricity. The number of costumers is 64.78 million houses. The average number of lamps and average wattage of lamps used in Indonesia are 8.35 points and 13.8 W, respectively. The number of lighting and percentage of electricity used for lighting in the residential sector in Indonesia are 20.03 TWh (21.02 %) and 497 million lamps, respectively. The projection shows that in the year 2026 the total energy for lighting and number of lamps in the residential sector are 25.05 TWh and 619 million, respectively. By promoting the present technology of high efficient lamps (LED), the potency of energy saving and emission reduction in 2026 are 2.6 TWh and 2.1 million tons CO2eq, respectively.

  2. Development of the cloud sharing system for residential earthquake responses using smartphones

    Science.gov (United States)

    Shohei, N.; Fujiwara, H.; Azuma, H.; Hao, K. X.

    2015-12-01

    Earthquake responses at residential depends on its building structure, site amplification, epicenter distance, and etc. Until recently, it was impossible to obtain the individual residential response by conventional seismometer in terms of costs. However, current technology makes it possible with the Micro Electro Mechanical Systems (MEMS) sensors inside mobile terminals like smartphones. We developed the cloud sharing system for residential earthquake response in local community utilizing mobile terminals, such as an iPhone, iPad, iPod touch as a collaboration between NIED and Hakusan Corp. The triggered earthquake acceleration waveforms are recorded at sampling frequencies of 100Hz and stored on their memories once an threshold value was exceeded or ordered information received from the Earthquake Early Warning system. The recorded data is automatically transmitted and archived on the cloud server once the wireless communication is available. Users can easily get the uploaded data by use of a web browser through Internet. The cloud sharing system is designed for residential and only shared in local community internal. Residents can freely add sensors and register information about installation points in each region. And if an earthquake occurs, they can easily view the local distribution of seismic intensities and even analyze waves.To verify this cloud-based seismic wave sharing system, we have performed on site experiments under the cooperation of several local communities, The system and experimental results will be introduced and demonstrated in the presentation.

  3. Feasibility study and roadmap to improve residential hot water distribution systems

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James D.

    2004-03-31

    Residential building practice currently ignores the losses of energy and water caused by the poor design of hot water systems. These losses include: the waste of water while waiting for hot water to get to the point of use; the wasted heat as water cools down in the distribution system after a draw; and the energy to reheat water that was already heated once before. A feasibility study and an action plan for a proposed research project involving residential hot water distribution systems is being developed. The feasibility study will use past work to estimate of hot water and energy loses caused by current hot water distribution systems in residences. Proposed research project, or roadmap, will develop recommendations for improvements to residential hot water distribution systems. The roadmap addresses the technical obstacles and gaps in our knowledge that prevent water and energy reductions and market adoption of water- and energy-efficient technologies. The initial results of the feasibility study are presented here along with a discussion of a roadmap to improve the efficiency of residential hot water distribution systems.

  4. Electric power of residential photovoltaic power system; Jutakuyo taiyoko hatsuden system no hatsudenryo

    Energy Technology Data Exchange (ETDEWEB)

    Asano, K.; Kawamura, H.; Yamanaka, S.; Kawamura, H.; Ono, H.; Hayashi, K.; Naganawa, H. [Meijo University, Nagoya (Japan); Asai, H.

    1996-10-27

    Measurement was done on the annual power generation of a residential photovoltaic power system that was most suitable for the present situation in utilizing solar energy; and an examination was made on the basis of the data of a module in which an optimal operation load control was separately installed in order to operate the system more effectively. As a result, it was found that the introduction of a 3kW class system was currently most desirable as a residential photovoltaic power system, and that the problem of the optimal operation load control was crucial for the more efficient power generation. The resistance value of the optimal operation load was stable between 6 and 8 ohm in the daytime in fine weather. However, it was observed that, where no sufficient insolation was expected, the optimal operation load was ten times as much as in fine weather, being easily influenced by the environmental elements. In addition, it was revealed that, if the operation load was fixed at a specific value (6 ohm) in a clear day, the power generation was only about 85% compared with the case of controlling the optimal operation load. This figure was obtained under comparatively favorable conditions, however. 8 refs., 7 figs.

  5. Model documentation report: Residential sector demand module of the national energy modeling system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    This report documents the objectives, analytical approach, and development of the National Energy Modeling System (NEMS) Residential Sector Demand Module. The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, and FORTRAN source code. This reference document provides a detailed description for energy analysts, other users, and the public. The NEMS Residential Sector Demand Module is currently used for mid-term forecasting purposes and energy policy analysis over the forecast horizon of 1993 through 2020. The model generates forecasts of energy demand for the residential sector by service, fuel, and Census Division. Policy impacts resulting from new technologies, market incentives, and regulatory changes can be estimated using the module. 26 refs., 6 figs., 5 tabs.

  6. Solar heating and cooling of residential buildings: sizing, installation and operation of systems. 1980 edition

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This manual was prepared as a text for a training course on solar heating and cooling of residential buildings. The course and text are directed toward sizing, installation, operation, and maintenance of solar systems for space heating and hot water supply, and solar cooling is treated only briefly. (MHR)

  7. Assessing the potential of residential HVAC systems for demand-side management

    NARCIS (Netherlands)

    van der Klauw, Thijs; Hoogsteen, Gerwin; Gerards, Marco Egbertus Theodorus; Hurink, Johann L.; Feng, Xianyong; Hebner, Robert E.

    This paper investigates the potential of residential heating, ventilation and air conditioning systems to contribute to dynamic demand-side management. Thermal models for seven houses in Austin, Texas are developed with the goal of using them in a planning based demand-side management methodology.

  8. Inlet Channel for a Ducted Fan Propulsion System of a Light Aircraft

    Directory of Open Access Journals (Sweden)

    E. Ritschl

    2003-01-01

    Full Text Available So-called "cold-jet" propulsion units consist of a piston engine, a blower and the necessary air duct. Till now, all attempts to utilize "cold-jet" propulsion units to maintain the thrust of an airplane have been unsuccessful. Analysis has shown that the main difficulty is the deformation of the flow field at the entry to the blower [1].

  9. Case study field evaluation of a systems approach to retrofitting a residential HVAC system

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; McWiliams, Jennifer A.; Konopacki, Steven J.

    2003-09-01

    This case study focusing on a residence in northern California was undertaken as a demonstration of the potential of a systems approach to HVAC retrofits. The systems approach means that other retrofits that can affect the HVAC system are also considered. For example, added building envelope insulation reduces building loads so that smaller capacity HVAC system can be used. Secondly, we wanted to examine the practical issues and interactions with contractors and code officials required to accomplish the systems approach because it represents a departure from current practice. We identified problems in the processes of communication and installation of the retrofit that led to compromises in the final energy efficiency of the HVAC system. These issues must be overcome in order for HVAC retrofits to deliver the increased performance that they promise. The experience gained in this case study was used to optimize best practices guidelines for contractors (Walker 2003) that include building diagnostics and checklists as tools to assist in ensuring the energy efficiency of ''house as a system'' HVAC retrofits. The best practices guidelines proved to be an excellent tool for evaluating the eight existing homes in this study, and we received positive feedback from many potential users who reviewed and used them. In addition, we were able to substantially improve the energy efficiency of the retrofitted case study house by adding envelope insulation, a more efficient furnace and air conditioner, an economizer and by reducing duct leakage.

  10. Day-ahead stochastic economic dispatch of wind integrated power system considering demand response of residential hybrid energy system

    International Nuclear Information System (INIS)

    Jiang, Yibo; Xu, Jian; Sun, Yuanzhang; Wei, Congying; Wang, Jing; Ke, Deping; Li, Xiong; Yang, Jun; Peng, Xiaotao; Tang, Bowen

    2017-01-01

    Highlights: • Improving the utilization of wind power by the demand response of residential hybrid energy system. • An optimal scheduling of home energy management system integrating micro-CHP. • The scattered response capability of consumers is aggregated by demand bidding curve. • A stochastic day-ahead economic dispatch model considering demand response and wind power. - Abstract: As the installed capacity of wind power is growing, the stochastic variability of wind power leads to the mismatch of demand and generated power. Employing the regulating capability of demand to improve the utilization of wind power has become a new research direction. Meanwhile, the micro combined heat and power (micro-CHP) allows residential consumers to choose whether generating electricity by themselves or purchasing from the utility company, which forms a residential hybrid energy system. However, the impact of the demand response with hybrid energy system contained micro-CHP on the large-scale wind power utilization has not been analyzed quantitatively. This paper proposes an operation optimization model of the residential hybrid energy system based on price response, integrating micro-CHP and smart appliances intelligently. Moreover, a novel load aggregation method is adopted to centralize scattered response capability of residential load. At the power grid level, a day-ahead stochastic economic dispatch model considering demand response and wind power is constructed. Furthermore, simulation is conducted respectively on the modified 6-bus system and IEEE 118-bus system. The results show that with the method proposed, the wind power curtailment of the system decreases by 78% in 6-bus system. In the meantime, the energy costs of residential consumers and the operating costs of the power system reduced by 10.7% and 11.7% in 118-bus system, respectively.

  11. Comprehensive Immunophenotypic Characterization of Adult and Fetal Testes, the Excretory Duct System, and Testicular and Epididymal Appendages.

    Science.gov (United States)

    Magers, Martin J; Udager, Aaron M; Chinnaiyan, Arul M; French, Diana; Myers, Jeffrey L; Jentzen, Jeffrey M; McHugh, Jonathan B; Heider, Amer; Mehra, Rohit

    2016-08-01

    The immunophenotype of a normal testis and the excretory duct system has not been studied comprehensively in fetal and adult patients without testicular disease or hormonal manipulation so far. In addition, testicular (TA) and epididymal (EA) appendages are frequent paratesticular structures without previously reported comprehensive immunophenotypic studies. Immunohistochemistry for multiple markers, including the androgen receptor (AR), the estrogen receptor (ER), the progesterone receptor (PR), the prostate-specific antigen, the prostate-specific membrane antigen, PAX8, WT1, calretinin, CK7, CK20, OCT4, SALL4, and CD117, was performed on full sections of testicular/paratesticular tissue from a large cohort of adult and fetal autopsy patients. In contrast to adult germ cells (GC), fetal GC strongly express OCT4 and CD117, although the expression of these proteins is lost in the early postnatal period; SALL4, in contrast, is expressed in both fetal and adult GC, with only weak and focal expression in adult patients. Fetal Sertoli cells (SC) express WT1 and calretinin strongly and diffusely, in contrast to adult SC. Both fetal and adult excretory duct systems express CK7 and PAX8 with frequent AR coexpression, and all 3 main segments of the excretory duct system (ductuli efferentes, epididymis, and vas deferens) have unique immunophenotypes. The rete testis also has a unique immunohistochemical expression pattern, which includes strong expression of CK7, PAX8, WT1, calretinin, and AR. Finally, of the adult autopsy patients examined, 80% had a TA, and 60% had an EA; these paratesticular structures occurred at stereotypical locations, demonstrated reproducible morphologic features, and had a unique immunophenotype relative to other studied structures, with strong CK7, PAX8, WT1, AR, ER, and PR coexpression. The testis and the paratestis may be involved by diverse neoplastic and non-neoplastic processes, and knowledge of the immunophenotypic expression spectrum of

  12. Tracer airflow measurement system (TRAMS)

    Science.gov (United States)

    Wang, Duo [Albany, CA

    2007-04-24

    A method and apparatus for measuring fluid flow in a duct is disclosed. The invention uses a novel high velocity tracer injector system, an optional insertable folding mixing fan for homogenizing the tracer within the duct bulk fluid flow, and a perforated hose sampling system. A preferred embodiment uses CO.sub.2 as a tracer gas for measuring air flow in commercial and/or residential ducts. In extant commercial buildings, ducts not readily accessible by hanging ceilings may be drilled with readily plugged small diameter holes to allow for injection, optional mixing where desired using a novel insertable foldable mixing fan, and sampling hose.

  13. Residential versus Communal Combination of Photovoltaic and Battery in Smart Energy Systems

    DEFF Research Database (Denmark)

    Marczinkowski, Hannah Mareike; Østergaard, Poul Alberg

    2017-01-01

    This paper presents an analysis of small consumers’ involvement in smart island energy systems with a focus on the technical feasibility of photovoltaic (PV) systems in combination with batter-ies. Two approaches may be observed in the literature: the optimization on a household level with the aim...... of being self-reliant versus coordinated and collective technologies with increased inte-gration across sectors and energy carriers. Thus, for household systems, the placement of a battery – whether aggregated or residential – creates the basis for this investigation. The study is based on the case...... of the Danish island Samsø for which the two battery approaches are simulated using the energy system simulation model EnergyPLAN. Results indicate a tendency towards aggre-gated batteries being more favourable from a systems perspective – while on the other hand, resi-dential batteries are more motivating...

  14. Closure of the cystic duct during laparoscopic cholecystectomy with a new feedback-controlled bipolar sealing system in case of biliary obstruction--an experimental study in pigs.

    Science.gov (United States)

    Shamiyeh, A; Vattay, P; Tulipan, L; Schrenk, P; Bogner, S; Danis, J; Wayand, W

    2004-01-01

    The excellent results of new devices like the new bipolar feedback-controlled sealing system (LigaSure) for closure of blood vessels encouraged surgeons to use these instruments for other structures like bile ducts. The aim of this study was to evaluate the feasibility of closure of cystic duct in case of biliary obstruction. Ten domestic pigs underwent laparoscopic cholecystectomy sealing the cystic duct with LigaSure. The common bile duct was closed with an endoclip to create a biliary hypertension. On the 12th postoperative day blood samples were taken for liver enzymes. At autopsy on day 15 the pigs were investigated for bile leaks or biliary peritonitis. The cystic duct was resected for histological examination. Seven pigs survived, one pig died during introduction of anesthesia, one on the 1st and one on the 2nd postoperative day without any findings at the autopsy. One pig out of 7 had a bile leak; the other 6 were without any sign of leakage. Histologically 3 pigs had a regular coagulation zone at the cystic duct, 3 had a total necrosis, one a partial necrosis of the mucosa only. Though there was only one insufficiency, the feedback-controlled bipolar vessel sealer cannot be recommended for biliary surgery with regard to the high rate of necrosis stated in our experiment.

  15. Residential Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde; Matsufuji, Y.

    2011-01-01

    are discussed in this chapter. Characterizing residential waste is faced with the problem that many residences already divert some waste away from the official collection systems, for example performing home composting of vegetable waste and garden waste, having their bundled newspaper picked up by the scouts...... twice a year or bringing their used furniture to the flea markets organized by charity clubs. Thus, much of the data available on residential waste represents collected waste and not necessarily all generated waste. The latter can only be characterized by careful studies directly at the source...

  16. SOLAR SYSTEMS FOR RESIDENTIAL BUILDINGS IN ACCORDANCE WITH OPERATING CONDITIONS OF THE REPUBLIC OF BELARUS

    Directory of Open Access Journals (Sweden)

    M. A. Rutkowski

    2017-01-01

    Full Text Available Solar systems are actively applied for heat supply of buildings in Europe. Usage of solar energy for heat supply of residential buildings is considered as rather efficient for the Republic of Belarus because total amount of direct and scattered solar radiation entering horizontal surface is equivalent to an average European index for the climate of Belarus. The paper analyzes an existing dependence on determination of solar system efficiency and proposes an amended formula for calculations while designing solar consumption systems and its legitimacy has been experimentally proved. A scheme of an experimental unit with explanations and a brief description for execution of experiments and main results of the completed investigations have been presented in the paper. Experiments have been carried out for solar systems with natural and forced coolant circulation. Attention has been paid to obtaining maximum possible temperature potential of the coolant during operation of the solar system within periods of high and low solar radiation intensity. Recommendations on practical application of solar systems for multi-storey residential buildings houses and mansion-type houses have been given in the paper. The paper presents technological principles of constructing “passive” solar heating devices. A comparison of traditionally applied and proposed alternative solar systems has been made for operational conditions in Belarus. The paper proposes a solar system for hot water supply of multi-storey buildings. The proposed system has found its first realization in the Republic while designing and constructing an energy-efficient demonstration 10-storey residential building in Mogilev within the framework of the UN Development Program project and Global Environment Fund “Improvement of energy efficiency for residential buildings in the Republic of Belarus”

  17. Development of a new energy efficiency rating system for existing residential buildings

    International Nuclear Information System (INIS)

    Koo, Choongwan; Hong, Taehoon; Lee, Minhyun; Seon Park, Hyo

    2014-01-01

    Building energy efficiency rating systems have been established worldwide to systematically manage the energy consumption of existing buildings. This study aimed to develop a new energy efficiency rating system for existing residential buildings from two perspectives: (i) establishment of reasonable and fair criteria for the building energy efficiency rating system; and (ii) establishment of comparative incentive and penalty programs to encourage the voluntary participation of all residents in the energy saving campaign. Based on the analysis of the conventional energy efficiency rating system for existing residential buildings, this study was conducted in five steps: (i) data collection and analysis; (ii) correlation analysis between the household size and the CO 2 emission density (i.e., CO 2 emission per unit area); (iii) cluster formation based on results of the correlation analysis using a decision tree; (iv) establishment of a new energy efficiency rating system for existing buildings; and (v) establishment of incentive and penalty programs using advanced case-based reasoning. The proposed system can allow a policymaker to establish a reasonable and fair energy efficiency rating system for existing residential buildings and can encourage the voluntary participation of all residents in the energy saving campaign. - Highlights: • A new energy efficiency rating system for the residential building was developed. • The incentive and penalty programs were established using an advanced CBR model. • The new system was established using reasonable and fair standards. • It allows all residents to voluntarily participate in the energy saving campaign. • It can be applied to any country or sector in the global environment

  18. Building America Case Study: Raised Ceiling Interior Duct System, New Smyrna, Florida (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-09-01

    One of BA-PIRC's longtime Habitat for Humanity partners, S.E. Volusia CO (SEVHFH), was interested in building a home to the new Challenge Home standards. SEVHFH routinely builds ENERGY STAR V3.1 homes. The only modification to their design needed to comply with the Challenge Home criteria was the interior duct requirement. Unwilling to incur the added costs of a foam roof deck or wall heights above 8 feet to accommodate a fur-down chase SEVHFH opted to build a fur-up or raised ceiling chase.

  19. Effectiveness of an energy-consumption information system for residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Tsuyoshi [Central Research Institute of Electric Power Industry, Tokyo (Japan); Inada, Ryo; Saeki, Osamu; Tsuji, Kiichiro [Osaka University, (Japan). Graduate School of Engineering

    2006-08-15

    The authors have proposed a method of reducing the energy consumption in residential buildings by providing household members with information on energy consumptions in their own houses. An on-line interactive 'energy-consumption information system' that displays power consumptions of, at most, 18 different appliances, power and city-gas consumption of the whole house and room temperature, for the purpose of motivating energy-saving activities has been constructed and the effectiveness of the system investigated by installing it in 10 residential buildings. The experiment showed that energy-saving consciousness was raised and energy consumption was in fact reduced by the energy-saving activities of the household members. In this paper, the system is described in detail and the effectiveness of reducing energy-consumption of the whole house and for space heating will be discussed. Also the energy-saving activities in a certain household are shown by using load duration curves. (author)

  20. Residential area streetlight intelligent monitoring management system based on ZigBee and GPRS

    Science.gov (United States)

    Liang, Guozhuang; Xu, Xiaoyu

    2017-05-01

    According to current situation of green environmental protection lighting policy and traditional residential lighting system automation degree, low energy efficiency, difficult to management and other problems, the residential area streetlight monitoring management system based on ZigBee and GPRS is proposed. This design is put forward by using sensor technology, ZigBee and GPRS wireless communication technology network. To realize intelligent lighting parameters adjustment, coordination control method of various kinds of sensors is used. The system through multiple ZigBee nodes topology network to collect street light's information, each subnet through the ZigBee coordinator and GPRS network to transmit data. The street lamps can be put on or off, or be adjusted the brightness automatic ally according to the surrounding environmental illumination.

  1. Adaptive Harmonic Compensation in Residential Distribution Grid by Roof-Top PV Systems

    DEFF Research Database (Denmark)

    Zangeneh Bighash, Esmaeil; Sadeghzadeh, Seyed Mohammad; Ebrahimzadeh, Esmaeil

    2018-01-01

    Fourier Transform (SDFT) algorithm and then individually compensate the measured harmonics by the proposed adaptive harmonic compensator. In the proposed approach, a current reference is separately determined for compensating each harmonic component. Then, a specific amount of additional current capacity...... grid- connected roof-top PV inverters in residential distribution grid can be an opportunity to engage these systems in the power quality issues as custom power devices. By implementing a proper control for roof-top PV inverters, these systems may in addition to inject the fundamental current......, additionally act like a virtual harmonic resistance and dedicate their additional current capacity to compensate the harmonics of residential distribution grid. In this paper, each roof-top PV system is a grid harmonic supervisor, where it continually measures the PCC voltage harmonics by Sliding Discrete...

  2. A generic-tee-plenum mixing system for application to single point aerosol sampling in stacks and ducts.

    Science.gov (United States)

    Han, Taewon; O'Neal, Dennis L; Ortiz, Carlos A

    2007-01-01

    The ANSI/HPS-N13.1-1999 standard is based on the concept of obtaining a single point representative sample from a location where the velocity and contaminant profiles are relatively uniform. It is difficult to predict the level of mixing in an arbitrary stack or duct without experimental data to meet the ANSI/HPS N13.1-1999 requirements. The goal of this study was to develop experimental data for a range of conditions in "S" (S-shaped configuration) duct systems with different mixing elements and "S" systems having one or two mixing elements. Results were presented in terms of the coefficients of variation (COVs) for velocity, tracer gas, and 10-mum aerodynamic diameter (AD) aerosol particle profiles at different downstream locations for each mixing element. Five mixing elements were tested, including a 90 degrees elbow, a commercial static mixer, a Small-Horizontal Generic-Tee-Plenum (SH-GTP), a Small-Vertical Generic-Tee-Plenum (SV-GTP), and a Large-Horizontal Generic-Tee-Plenum (LH-GTP) system. The COVs for velocity, gas concentration, and aerosol particles for the three GTP systems were all determined to be less than 8%. Tests with two different sizes of GTPs were conducted, and the results showed the performance of the GTPs was relatively unaffected by either size or velocity as reflected by the Reynolds number. The pressure coefficients were 0.59, 0.57, and 0.65, respectively, for the SH-GTP, SV-GTP, and LH-GTP. The pressure drop for the GTPs was approximately twice that of the round elbow, but a factor of 5 less than a Type IV Air Blender. The GTP was developed to provide a sampling location less than 4-duct diameters downstream of a mixing element with low pressure drop condition. The object of the developmental effort was to provide a system that could be employed in new stack; however, the concept of GTPs could also be retrofitted onto existing system applications as well. Results from these tests show that the system performance is well within the ANSI

  3. Impact of the duct static pressure reset control strategy on the energy consumption by the HVAC system

    Directory of Open Access Journals (Sweden)

    Walaszczyk Juliusz

    2017-01-01

    Full Text Available This article addresses different duct static pressure control strategies which could be implemented in variable air volume air-conditioning systems (VAV. Two pressure reset control strategies are compared to the commonly used control solution based on the “Constant static pressure” method. First pressure reset control strategy, known as PID Control, uses signals from VAV boxes controllers to reset duct static pressure in a way that one of the VAV dampers is maintained almost entirely open. Second strategy decreases static pressure setpoint until an adjustable number of pressure requests occur. As a response to the certain amount of requests, static pressure setpoint is increased. This strategy is called Trim & Respond. Both static pressure reset control strategies described in this paper are considered to have more significant potential for energy savings than the “Constant static pressure” method. In order to validate this potential, several simulations for different control strategies were carried out and the obtained results are compared and analysed. The theoretical limit of the energy savings - set of the optimal control actions, was estimated with Nelder-Mead algorithm and also presented in this article. General description of the static pressure control strategies "Constant static pressure", PID Control and Trim & Respond is given.

  4. Procedures and Standards for Residential Ventilation System Commissioning: An Annotated Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Stratton, J. Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wray, Craig P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-04-01

    Beginning with the 2008 version of Title 24, new homes in California must comply with ANSI/ASHRAE Standard 62.2-2007 requirements for residential ventilation. Where installed, the limited data available indicate that mechanical ventilation systems do not always perform optimally or even as many codes and forecasts predict. Commissioning such systems when they are installed or during subsequent building retrofits is a step towards eliminating deficiencies and optimizing the tradeoff between energy use and acceptable IAQ. Work funded by the California Energy Commission about a decade ago at Berkeley Lab documented procedures for residential commissioning, but did not focus on ventilation systems. Since then, standards and approaches for commissioning ventilation systems have been an active area of work in Europe. This report describes our efforts to collect new literature on commissioning procedures and to identify information that can be used to support the future development of residential-ventilation-specific procedures and standards. We recommend that a standardized commissioning process and a commissioning guide for practitioners be developed, along with a combined energy and IAQ benefit assessment standard and tool, and a diagnostic guide for estimating continuous pollutant emission rates of concern in residences (including a database that lists emission test data for commercially-available labeled products).

  5. The impact of residential demand response on the costs of a fossil-free system reserve

    DEFF Research Database (Denmark)

    Katz, Jonas; Balyk, Olexandr; Hevia Koch, Pablo Alejandro

    2016-01-01

    In order to achieve a better understanding of the system value of residential demand response, we study the potential impact of flexible demand on the costs of system reserves in a fossil-free electricity supply. Comparing these costs with traditional means of regulation our analysis aims...... to contribute to determining the least-cost options for regulation in a fossil-free power system. We extend an existing energy system model with demand response and reserve modelling and analyse the impact for the case of Denmark in 2035 to reflect a system based on renewable resources for electricity...

  6. Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System

    Energy Technology Data Exchange (ETDEWEB)

    Agamy, Mohammed [GE Global Research Center, Niskayuna, NY (United States)

    2015-10-27

    The “Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System” program is focused on developing innovative concepts for residential photovoltaic (PV) systems with the following objectives: to create an Innovative micro-inverter topology that reduces the cost from the best in class micro-inverter and provides high efficiency (>96% CEC - California Energy Commission), and 25+ year warranty, as well as reactive power support; integrate micro-inverter and PV module to reduce system price by at least $0.25/W through a) accentuating dual use of the module metal frame as a large area heat spreader reducing operating temperature, and b) eliminating redundant wiring and connectors; and create micro-inverter controller handles smart grid and safety functions to simplify implementation and reduce cost.

  7. An analysis of hybrid power generation systems for a residential load

    OpenAIRE

    Ceran Bartosz; Hassan Qusay; Jaszczur Marek; Sroka Krzysztof

    2017-01-01

    This paper presents the results of an energetic and economical analysis of a hybrid power generation system (HPGS) which utilises photovoltaic modules, wind turbines, fuel cells and an electrolyzer with hydrogen tank working as the energy storage. The analysis was carried out for three different residential loads, local solar radiation and local wind speed, based on the real measurement values. The analysis shows the optimal solution and the limits of the investment costs required for the sys...

  8. Field Testing of Energy-Efficient Flood-Damage-Resistant Residential Envelope Systems Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Aglan, H.

    2005-08-04

    The primary purpose of the project was to identify materials and methods that will make the envelope of a house flood damage resistant. Flood damage resistant materials and systems are intended to be used to repair houses subsequent to flooding. This project was also intended to develop methods of restoring the envelopes of houses that have been flooded but are repairable and may be subject to future flooding. Then if the house floods again, damage will not be as extensive as in previous flood events and restoration costs and efforts will be minimized. The purpose of the first pair of field tests was to establish a baseline for typical current residential construction practice. The first test modules used materials and systems that were commonly found in residential envelopes throughout the U.S. The purpose of the second pair of field tests was to begin evaluating potential residential envelope materials and systems that were projected to be more flood-damage resistant and restorable than the conventional materials and systems tested in the first pair of tests. The purpose of testing the third slab-on-grade module was to attempt to dry flood proof the module (no floodwater within the structure). If the module could be sealed well enough to prevent water from entering, then this would be an effective method of making the interior materials and systems flood damage resistant. The third crawl space module was tested in the same manner as the previous modules and provided an opportunity to do flood tests of additional residential materials and systems. Another purpose of the project was to develop the methodology to collect representative, measured, reproducible (i.e. scientific) data on how various residential materials and systems respond to flooding conditions so that future recommendations for repairing flood damaged houses could be based on scientific data. An additional benefit of collecting this data is that it will be used in the development of a standard test

  9. Grid-Competitive Residential and Commercial Fully Automated PV Systems Technology: Final technical Report, August 2011

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Katie E.; Cousins, Peter; Culligan, Matt; Jonathan Botkin; DeGraaff, David; Bunea, Gabriella; Rose, Douglas; Bourne, Ben; Koehler, Oliver

    2011-08-26

    Under DOE's Technology Pathway Partnership program, SunPower Corporation developed turn-key, high-efficiency residential and commercial systems that are cost effective. Key program objectives include a reduction in LCOE values to 9-12 cents/kWh and 13-18 cents/kWh respectively for the commercial and residential markets. Target LCOE values for the commercial ground, commercial roof, and residential markets are 10, 11, and 13 cents/kWh. For this effort, SunPower collaborated with a variety of suppliers and partners to complete the tasks below. Subcontractors included: Solaicx, SiGen, Ribbon Technology, Dow Corning, Xantrex, Tigo Energy, and Solar Bridge. SunPower's TPP addressed nearly the complete PV value chain: from ingot growth through system deployment. Throughout the award period of performance, SunPower has made progress toward achieving these reduced costs through the development of 20%+ efficient modules, increased cell efficiency through the understanding of loss mechanisms and improved manufacturing technologies, novel module development, automated design tools and techniques, and reduced system development and installation time. Based on an LCOE assessment using NREL's Solar Advisor Model, SunPower achieved the 2010 target range, as well as progress toward 2015 targets.

  10. Assessment of retrofit automatic vent dampers for residential heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, D.L.; Wilson, R.P. Jr.; Ashley, L.E.; Butterfield, J.F.

    1977-11-01

    Automatic vent dampers are devices installed in the exhaust vent of a central heating system which prohibit the chimney flow of warm air from the dwelling space and from within the furnace when the heating system is not operating. An investigation of the effect of thermally actuated or electrically actuated dampers on home energy conservation, their cost, and safety is described. Eleven heating system types in 2 geographic regions were used in this study. It was determined that good quality, safe electrically actuated dampers are available in the U.S. and that thermally actuated units will be available soon; an average savings of approximately 8% in home heating cost could be achieved by using automatic dampers with suitable furnace systems in regions with a heating season of more than 4000 degree-days; the cost of the automatic dampers is from $65 to $140 with a payback period of 3 to 4 1/2 y; and, with the average heating system, vent damper retrofit alone is not as an attractive energy conservation option as combined vent damper, intermittent ignition device retrofit, and reduced gas orifice. (LCL)

  11. Solar Heating and Cooling of Residential Buildings: Design of Systems.

    Science.gov (United States)

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    This is the second of two training courses designed to develop the capability of practitioners in the home building industry to design solar heating and cooling systems. The course is organized in 23 modules to separate selected topics and to facilitate learning. Although a compact schedule of one week is shown, a variety of formats can be…

  12. ECOLO-HOUSE in the heavy snow-fall region. Study of the ventilating function that the heat collecting system of the air duct utilizing attic has; Yukiguni ECOLO-HOUSE. Kison kaoku no yaneura wo riyoshita duct shunetsu system kanki kino hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Umemiya, H.; Hirosawa, K. [Yamagata University, Yamagata (Japan)

    1997-11-25

    This paper reports a duct heat collecting system installed in the ECOLO-HOUSE for snow countries. This system is an air heat collecting system of the outside air introducing type utilizing as a solar heat collector the single pitch roof often seen in snow countries. Outside air is introduced from below eaves into a heat collecting duct made by nailing plywoods onto rafters from the attic side to collect heat on the roof. Operating a sirocco fan connected to the induction duct located on the high-floor foundation sucks outside air from an air intake opening under the eaves into the heat collecting duct. Air which has absorbed heat on the roof and been warmed in the heat collecting duct by insolation goes into a heat collecting chamber. The air is sent into the high-floor foundation through the induction duct laid from the heat collecting chamber. Air is exchanged 8.7 times by the fan when it is operated all day continuously. Condensation in the fuel chamber floor and walls during the rainy season has disappeared, and so has odor at the same time. As a result of the humidity measurement, a location into which warm air is sent has difference in humidity as great as 15% from a location where no warm air is sent. 2 refs., 6 figs., 2 tabs.

  13. New String Reconfiguration Technique for Residential Photovoltaic System Generation Enhancement

    Directory of Open Access Journals (Sweden)

    CORBA, Z.

    2016-02-01

    Full Text Available Improvement of photovoltaic (PV power plant performance under partial shading conditions aiming to increase electrical energy generation is in the focus of this research. This paper proposes the performance optimization of PV power plant under partial shading conditions by new PV string reconfiguration technique. The Matlab/Simulink model is used to simulate the operation of the PV string under partial shading conditions and with the proposed recombination technique. Simulated operational conditions have experimentally been verified by string characteristics measurement on the existing roof-top PV system at the Faculty of Technical Sciences in Novi Sad. Simulation and experimental results showed a high degree of matching, while the obtained values proved that proposed method leads to output power increase and higher PV system generation in PV string operation under partial shading.

  14. Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems

    OpenAIRE

    Sherman, Max H.

    2011-01-01

    Existing ventilation standards, including American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Standard 62.2, specify continuous operation of a defined mechanical ventilation system to provide minimum ventilation, with time-based intermittent operation as an option. This requirement ignores several factors and concerns including: other equipment such as household exhaust fans that might incidentally provide ventilation, negative impacts of ventilation when outd...

  15. An Economic Analysis of Residential PV System for Adiyaman, Turkey

    Directory of Open Access Journals (Sweden)

    Haci SOGUKPINAR

    2015-07-01

    Full Text Available Solar energy constitutes the main source of all energy sources and it is one of the most important renewable energy sources in terms of huge potential. As with other energy sources not just in certain places in the world, everywhere have the potential where the sun rises and set. Turkey is located on the sunny area and solar energy generation is quite rich in potential. Together with the substantial increase in the efficiency of photovoltaic cells, generating electricity from solar energy is becoming increasingly common. Especially in places where no grid connection, photovoltaic cells is very useful in supplying the energy needs. In this study, Turkey's solar energy potential was analyzed, and PV systems to meet the electricity needs of a home were analyzed economically. Consequently, to meet the electricity needs of a house in Adiyaman conditions that require a surface area of 24 m2 with a PV system, and this system was determined to be able to amortize itself in 10 years.

  16. Economic performance and policies for grid-connected residential solar photovoltaic systems in Brazil

    International Nuclear Information System (INIS)

    Mitscher, Martin; Rüther, Ricardo

    2012-01-01

    We analyze the economic competitiveness of grid-connected, distributed solar photovoltaic generation through small-scale rooftop installations in five Brazilian state-capitals. The locations represent a comprehensive set of the two essential parameters for the economic viability of PV—solar irradiation and local electricity tariffs. Levelized electricity costs (LEC) for PV generation and net present values (NPV) for a specific PV system are presented. The analysis comprises three different interest rate scenarios reflecting different conditions for capital acquisition to finance the generators; subsidized, mature market and country-specific risk-adjusted interest. In the NPV analysis, revenue flow is modeled by the sale of PV electricity at current residential tariffs assuming net metering. Using subsidized interest rates, the analysis shows that solar PV electricity is already competitive in Brazil, while in the country-specific risk-adjusted rate, the declining, but still high capital costs of PV make it economically unfeasible. At a mature market interest rate, PV competitiveness is largely dependent on the residential tariff. Economic competitiveness in this scenario is given for locations with high residential tariffs. We demonstrate the high potential of distributed generation with photovoltaic installations in Brazil, and show that under certain conditions, grid-connected PV can be economically competitive in a developing country. - Highlights: ► Debt financed grid-connected PV on Brazilian rooftops can be economically feasible since 2011. ► The cost of capital in Brazil is the decisive parameter in PV competitiveness with conventional generation sources. ► Low-cost, long-term financing is an essential requirement for PV to become an economically justifiable generation alternative. ► The Brazilian market holds huge potential for distributed, residential rooftop PV systems of small size.

  17. A low-cost-solar liquid desiccant system for residential cooling

    Science.gov (United States)

    Ware, Joel D., III

    The use of liquid desiccants for dehumidification of heating, ventilation, and air conditioning (HVAC) process air is becoming a more promising concept as the drive for energy conservation continues to grow. Recently, liquid desiccant systems have been implemented on the commercial level in conjunction with evaporative coolers and have recorded energy savings upwards of 50%. The aim of this research is to test the potential liquid desiccant systems have on the residential level when paired with a conventional vapor compression cycle and to construct a system that would overcome some of its barriers to the residential market. A complete low-cost-solar liquid desiccant system was designed, constructed, and tested in the Off-Grid Zero Emissions Building (OGZEB) at the Florida State University. Key design characteristics include turbulent process air flow through the conditioner and airside heating in the regenerator. The system was tested in the two following ways: (1) for the energy savings while maintaining a constant temperature over a twenty four hour period and (2) for the energy savings over a single cooling cycle. The liquid desiccant system achieved a maximum energy savings of 38% over a complete day and 52% over a single cooling cycle. It was projected that the system has the potential to save 1064 kWh over the course of a year. When combined with a renewable source of heat for regeneration, liquid desiccant systems become very cost effective. The levelized cost of energy for the combination of the liquid desiccant system and solar thermal collectors was calculated to be 7.06 C/kWh with a payback period of 4.4 years. This research provides evidence of the technology's potential on the residential sector and suggests ways for it to become competitive in the market.

  18. Methods of Improving Water Treatment Systems for Individual Residential Houses

    Directory of Open Access Journals (Sweden)

    Pavlov Sergey

    2016-01-01

    Full Text Available One of hot topics for ecological management is sewage treatment today in places where there is no sewerage. The volume of country construction in territories, which are not connected to the public sewage system increasing nowadays. Therefore, problem of wastewater treatment take place. Currently, there are a lot of different designs of local waste treatment plants is offered to consumers. However, a large number of negative reviews indicate serious shortcomings in most of the local plants offered in the market. The purpose of this paper is the proposal of improvement of the most common local treatment plants in Russia.

  19. Diversidad morfológica del sistema de conductos excretores de los peces teleósteos Morphological diversity of the excretory duct system of teleostean fishes

    Directory of Open Access Journals (Sweden)

    Abraham Kobelkowsky

    2007-06-01

    Full Text Available Mediante el análisis anatómico de 70 especies de teleósteos, pertenecientes a 62 géneros, 39 familias y 20 órdenes, se reconoce la diversidad morfológica de los conductos excretores y de la vejiga urinaria. Se define como un patrón morfológico general de los teleósteos la fusión de ambos conductos arquinéfricos en el conducto urinario común y, en los machos, la unión del conducto urinario común con el conducto espermático común, formándose el conducto urogenital. Se reconoce una relación inversa de la longitud de los conductos arquinéfricos y la longitud de los riñones. Se describe la diversidad de situaciones morfológicas del trayecto y fusiones de los conductos excretores. Se reconoce la diversidad de formas de vejiga urinaria. Resalta la “inversión” de la posición de los conductos urinarios y urogenitales en los Pleuronectiformes. Se sugiere el origen de la vejiga urinaria a partir del conducto urinario común. Se manifiesta en algunas especies el dimorfismo sexual en la forma de las papilas urinaria y urogenital.By means of an anatomical analysis from 70 species of teleostean fishes, belonging to 62 genera, and 39 families, and 20 orders, the morphological diversity of the urinary Duch system is described. A general morphological teleostean pattern is defined as the fusion of both archinephric ducts in the common urinay duct, and the fusion in malesof the common urinary duct with the common spermatic duct in the urogenital duct. A relation between the length of thekidney and of the archinephric ducts is recongnized. The trajectory of the urinary ducts is described, with the “reversal”of the orientation of the urinary and urogenital ducts in Pleuronectiformes being noteworthy. The origin of the urinary bladder from the common urinary duct is suggested.

  20. VOLTTRON-Based System for Providing Ancillary Services with Residential Building Loads

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin

    2016-07-01

    Ancillary services entail controlled modulation of building equipment to maintain a stable balance of generation and load in the power system. Ancillary services include frequency regulation and contingency reserves, whose acting time ranges from several seconds to several minutes. Many pilot studies have been implemented to use industrial loads to provide ancillary services, and some have explored services from commercial building loads or electric vehicle charging loads. Residential loads, such as space conditioning and water heating, represent a largely untapped resource for providing ancillary services. The residential building sector accounts for a significant fraction of the total electricity use in the United States. Many loads in residential buildings are flexible and could potentially be curtailed or shifted at the request of the grid. However, there are many barriers that prevent residential loads being widely used for ancillary services. One of the major technical barriers is the lack of communication capabilities between end-use devices and the grid. End-use devices need to be able to receive the automatic generation control (AGC) signal from the grid operator and supply certain types of telemetry to verify response. With the advance of consumer electronics, communication-enabled, or 'connected,' residential equipment has emerged to overcome the communication barrier. However, these end-use devices have introduced a new interoperability challenge due to the existence of numerous standards and communication protocols among different end devices. In this paper, we present a VOLTTRON-based system that overcomes these technical challenges and provides ancillary services with residential loads. VOLTTRON is an open-source control and sensing platform for building energy management, facilitating interoperability solutions for end devices. We have developed drivers to communicate and control different types of end devices through standard

  1. Economics of residential solar hot water heating systems in Malaysia

    International Nuclear Information System (INIS)

    Abdulmula, Ahmed Mohamed Omer; Sopian, Kamaruzzaman; Haj Othman, Mohd Yosof

    2006-01-01

    Malaysia has favorable climatic conditions for the development of solar energy due to the abundant sunshine and is considered good for harnessing energy from the sun. This is because solar hot water can represent the large energy consumer in Malaysian households but, because of the high initial cost of Solar Water Heating Systems (SWHSs) and easily to install and relatively inexpensive to purchase electric water heaters, many Malyaysian families are still using Electric Water Heaters to hot their water needs. This paper is presented the comparing of techno-economic feasibility of some models of SWHS from Malaysian's market with the Electric Water Heaters )EWH) by study the annual cost of operation for both systems. The result shows that the annual cost of the electrical water heater becomes greater than than the annual cost of the SWHS for all models in long-team run so it is advantageous for the family to use the solar water heater, at least after 4 years. In addition with installation SWHS the families can get long-term economical benefits, environment friendly and also can doing its part to reduce this country's dependence on foreign oil that is price increase day after day.(Author)

  2. Residential Solar PV Systems in the Carolinas: Opportunities and Outcomes.

    Science.gov (United States)

    Alqahtani, Bandar Jubran; Holt, Kyra Moore; Patiño-Echeverri, Dalia; Pratson, Lincoln

    2016-02-16

    This paper presents a first-order analysis of the feasibility and technical, environmental, and economic effects of large levels of solar photovoltaic (PV) penetration within the services areas of the Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP). A PV production model based on household density and a gridded hourly global horizontal irradiance data set simulates hourly PV power output from roof-top installations, while a unit commitment and real-time economic dispatch (UC-ED) model simulates hourly system operations. We find that the large generating capacity of base-load nuclear power plants (NPPs) without ramping capability in the region limits PV integration levels to 5.3% (6510 MW) of 2015 generation. Enabling ramping capability for NPPs would raise the limit of PV penetration to near 9% of electricity generated. If the planned retirement of coal-fired power plants together with new installations and upgrades of natural gas and nuclear plants materialize in 2025, and if NPPs operate flexibly, then the share of coal-fired electricity will be reduced from 37% to 22%. A 9% penetration of electricity from PV would further reduce the share of coal-fired electricity by 4-6% resulting in a system-wide CO2 emissions rate of 0.33 to 0.40 tons/MWh and associated abatement costs of 225-415 (2015$ per ton).

  3. An analysis of hybrid power generation systems for a residential load

    Directory of Open Access Journals (Sweden)

    Ceran Bartosz

    2017-01-01

    Full Text Available This paper presents the results of an energetic and economical analysis of a hybrid power generation system (HPGS which utilises photovoltaic modules, wind turbines, fuel cells and an electrolyzer with hydrogen tank working as the energy storage. The analysis was carried out for three different residential loads, local solar radiation and local wind speed, based on the real measurement values. The analysis shows the optimal solution and the limits of the investment costs required for the system construction. The presented results confirm the effectiveness of the proposed approach, which could be assumed as a very useful tool in the design and analysis of a hybrid power generation system.

  4. Noise suppression in duct

    International Nuclear Information System (INIS)

    Ahmed, A.; Barfeh, M.A.G.

    2001-01-01

    In air-conditioning system the noise generated by supply fan is carried by conditioned air through the ductwork. The noise created in ductwork run may be transmission, regenerative and ductborne. Transmission noise is fan noise, regenerative noise is due to turbulence in flow and ductborne noise is the noise radiating from duct to surroundings. Some noise is attenuated in ducts also but if noise level is high then it needs to be attenuated. A simple mitre bend can attenuate-noise. This principle is extended to V and M-shape ducts with inside lining of fibreglass, which gave maximum attenuation of 77 dB and 62 dB respectively corresponding to 8 kHz frequency as compared to mitre, bend giving maximum 18 dB attenuation. Sound level meter measured sound levels with octave band filter and tests were conducted in anechoic room. A V-shape attenuator can be used at fan outlet and high frequency noise can be minimized greatly. (author)

  5. Ion transport mechanisms in the mesonephric collecting duct system of the toad Bufo bufo: microelectrode recordings from isolated and perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2004-01-01

    It is not clear how and whether terrestrial amphibians handle NaCl transport in the distal nephron. Therefore, we studied ion transport in isolated perfused collecting tubules and ducts from toad, Bufo bufo, by means of microelectrodes. No qualitative difference in basolateral cell membrane...... and amiloride application showed a small apical Na+ conductance. Arginine vasotocin depolarized Vbl. The small apical Na+ conductance indicates that the collecting duct system contributes little to NaCl reabsorption when compared to aquatic amphibians. In contrast, Vbl rapidly depolarized upon lowering of [Na...

  6. Latino residential segregation and self-rated health among Latinos: Washington State Behavioral Risk Factor Surveillance System, 2012–2014

    Science.gov (United States)

    Plascak, Jesse J.; Molina, Yamile; Wu-Georges, Samantha; Idris, Ayah; Thompson, Beti

    2016-01-01

    The relationship between Latino residential segregation and self-rated health (SRH) is unclear, but might be partially affected by social capital. We investigated the association between Latino residential segregation and SRH while also examining the roles of various social capital measures. Washington State Behavioral Risk Factor Surveillance System (2012–2014) and U.S. Census data were linked by zip code and zip code tabulation area. Multilevel logistic regression models were used to estimate odds of good or better SRH by Latino residential segregation, measured by the Gini coefficient, and controlling for sociodemographic, acculturation and social capital measures of neighborhood ties, collective socialization of children, and social control. The Latino residential segregation – SRH relationship was convex, or ‘U’-shaped, such that increases in segregation among Latinos residing in lower segregation areas was associated with lower SRH while increases in segregation among Latinos residing in higher segregation areas was associated with higher SRH. The social capital measures were independently associated with SRH but had little effect on the relationship between Latino residential segregation and SRH. A convex relationship between Latino residential segregation and SRH could explain mixed findings of previous studies. Although important for SRH, social capital measures of neighborhood ties, collective socialization of children, and social control might not account for the relationship between Latino residential segregation and SRH. PMID:27173739

  7. Practical Diagnostics for Evaluating Residential Commissioning Metrics

    Energy Technology Data Exchange (ETDEWEB)

    Wray, Craig; Walker, Iain; Siegel, Jeff; Sherman, Max

    2002-06-11

    In this report, we identify and describe 24 practical diagnostics that are ready now to evaluate residential commissioning metrics, and that we expect to include in the commissioning guide. Our discussion in the main body of this report is limited to existing diagnostics in areas of particular concern with significant interactions: envelope and HVAC systems. These areas include insulation quality, windows, airtightness, envelope moisture, fan and duct system airflows, duct leakage, cooling equipment charge, and combustion appliance backdrafting with spillage. Appendix C describes the 83 other diagnostics that we have examined in the course of this project, but that are not ready or are inappropriate for residential commissioning. Combined with Appendix B, Table 1 in the main body of the report summarizes the advantages and disadvantages of all 107 diagnostics. We first describe what residential commissioning is, its characteristic elements, and how one might structure its process. Our intent in this discussion is to formulate and clarify these issues, but is largely preliminary because such a practice does not yet exist. Subsequent sections of the report describe metrics one can use in residential commissioning, along with the consolidated set of 24 practical diagnostics that the building industry can use now to evaluate them. Where possible, we also discuss the accuracy and usability of diagnostics, based on recent laboratory work and field studies by LBNL staff and others in more than 100 houses. These studies concentrate on evaluating diagnostics in the following four areas: the DeltaQ duct leakage test, air-handler airflow tests, supply and return grille airflow tests, and refrigerant charge tests. Appendix A describes those efforts in detail. In addition, where possible, we identify the costs to purchase diagnostic equipment and the amount of time required to conduct the diagnostics. Table 1 summarizes these data. Individual equipment costs for the 24

  8. Energy, economic and environmental analysis on RET-hydrogen systems in residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Beccali, M.; Brunone, S.; Cellura, M.; Franzitta, V. [Dipartimento di Ricerche Energetiche e Ambientali, Universita degli Studi di Palermo, Viale delle Scienze, 90128 Palermo (Italy)

    2008-03-15

    The aim of this study was to analyze energy, economic and environmental performances of a set of scenarios dealing with the production and the use of hydrogen as energy carriers in residential applications in combination with renewable energy (RE). The authors also made an investigation into the required economic conditions necessary for making H{sub 2}-RE residential systems competitive with conventional ones, which are based on the use of grid electricity and natural gas. A case study was enacted in a small residential district in Palermo (Italy) made by five multi-storey buildings. Many energy systems have been considered according to several fuel-device combinations (electric grid, fuel cell, PV panels, wind turbines, boiler etc.). The software HOMER (hybrid optimization model for electric renewables), developed by NREL and Midwest Research Institute (USA), was used, in order to study the energy balance of the system and its components. Moreover, it was possible to simulate the hourly operation of each system and to calculate technical, economic and environmental performance parameters. The net present cost and the cost of energy are the two main parameters used to compare economic performances of the systems with both actual and expected costs in the medium term. A sensitivity analysis was carried out in order to appreciate the most important parameters influencing the economic performances of the systems and to define possible future scenarios of competitiveness between technologies. Emissions of CO{sub 2} (the most important greenhouse gas) and other pollutants have been considered for an environmental benefits analysis. (author)

  9. Renewable energy production support schemes for residential-scale solar photovoltaic systems in Nordic conditions

    International Nuclear Information System (INIS)

    Hirvonen, Janne; Kayo, Genku; Cao, Sunliang; Hasan, Ala; Sirén, Kai

    2015-01-01

    The objective of this study was to examine the effect of production-based support schemes on the economic feasibility of residential-scale PV systems (1–10 kW) in Finland. This was done by calculating the payback time for various sizes of newly installed PV systems for a Finnish detached house with district heating. Three types of economic support schemes (guaranteed selling price, fixed premiums and self-consumption incentives) were tested in an hourly simulation. The load of the building was based on real-life measurements, while PV output was simulated with TRNSYS software. The energy results were post-processed with economic data in MATLAB to find the payback time. Hourly electricity prices from the Nordic energy market were used with PV system prices from Finnish companies. Unsubsidised residential PV systems in Finland had payback times of more than 40 years. The production-based support for PV generation needs to be two to three times the buying price of electricity, to make it possible to pay back the initial investment in 20 years. Low capacity systems with more than 50% self-consumption (under 3 kW) were favoured by self-consumption incentives, while high capacity systems with less than 40% self-consumption (over 5 kW) were favoured by the FIT-type support schemes. - Highlights: • Unsubsidised residential PV is uneconomical in Finland. • Support rate must be 2 times the electricity price for reasonable payback time. • Even using all electricity on-site is not profitable enough without support. • Assumed real interest rate had great influence on payback time. • Hourly electricity prices are much lower than average values from Finnish statistics

  10. Molecular Mechanisms of Bile Duct Development

    OpenAIRE

    Zong, Yiwei; Stanger, Ben Z.

    2010-01-01

    The mammalian biliary system, consisting of the intrahepatic and extrahepatic bile ducts, is responsible for transporting bile from the liver to the intestine. Bile duct dysfunction, as is seen in some congenital biliary diseases such as Alagille syndrome and biliary atresia, can lead to the accumulation of bile in the liver, preventing the excretion of detoxification products and ultimately leading to liver damage. Bile duct formation requires coordinated cell-cell interactions, resulting in...

  11. Energy and exergy performance of residential heating systems with separate mechanical ventilation

    International Nuclear Information System (INIS)

    Zmeureanu, Radu; Yu Wu, Xin

    2007-01-01

    The paper brings new evidence on the impact of separate mechanical ventilation system on the annual energy and exergy performance of several design alternatives of residential heating systems, when they are designed for a house in Montreal. Mathematical models of residential heating, ventilation and domestic hot water (HVAC-DHW) systems, which are needed for this purpose, are developed and furthermore implemented in the Engineering Equation Solver (EES) environment. The Coefficient of Performance and the exergy efficiency are estimated as well as the entropy generation and exergy destruction of the overall system. The equivalent greenhouse gas emissions due to the on-site and off-site use of primary energy sources are also estimated. The addition of a mechanical ventilation system with heat recovery to any HVAC-DHW system discussed in the paper increases the energy efficiency; however, it decreases the exergy efficiency, which indicates a potential long-term damaging impact on the natural environment. Therefore, the use of a separate mechanical ventilation system in a house should be considered with caution, and recommended only when other means for controlling the indoor air quality cannot be applied

  12. Optimal Sizing of Vanadium Redox Flow Battery Systems for Residential Applications Based on Battery Electrochemical Characteristics

    Directory of Open Access Journals (Sweden)

    Xinan Zhang

    2016-10-01

    Full Text Available The penetration of solar photovoltaic (PV systems in residential areas contributes to the generation and usage of renewable energy. Despite its advantages, the PV system also creates problems caused by the intermittency of renewable energy. As suggested by researchers, such problems deteriorate the applicability of the PV system and have to be resolved by employing a battery energy storage system (BESS. With concern for the high investment cost, the choice of a cost-effective BESS with proper sizing is necessary. To this end, this paper proposes the employment of a vanadium redox flow battery (VRB, which possesses a long cycle life and high energy efficiency, for residential users with PV systems. It further proposes methods of computing the capital and maintenance cost of VRB systems and evaluating battery efficiency based on VRB electrochemical characteristics. Furthermore, by considering the cost and efficiency of VRB, the prevalent time-of-use electricity price, the solar feed-in tariff, the solar power profile and the user load pattern, an optimal sizing algorithm for VRB systems is proposed. Simulation studies are carried out to show the effectiveness of the proposed methods.

  13. Meeting the Electrical Energy Needs of a Residential Building with a Wind-Photovoltaic Hybrid System

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Mohammadnezami

    2015-03-01

    Full Text Available A complete hybrid system including a photovoltaic cell, a wind turbine, and battery is modeled to determine the best approach for sizing the system to meet the electrical energy needs of a residential building. In evaluating system performance, the city of Tehran is used as a case study. Matlab software is used for analyzing the data and optimizing the system for the given application. Further, the cost of the system design is investigated, and shows that the electrical cost of the hybrid system in Tehran is 0.62 US$/kWh, which is 78% less expensive than a wind turbine system and 34% less expensive than a photovoltaic system.

  14. Market Assessment of Residential Grid-Tied PV Systems in Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, B.; Coburn, T.

    2000-09-29

    This report presents research done in response to a decision by the Colorado Governor's Office of Energy Conservation and Management (OEC) and Colorado utility companies to consider making residential grid-tied photovoltaic (PV) systems available in Colorado. The idea was to locate homeowners willing to pay the costs of grid-tied PV (GPV) systems without batteries-$8,000 or $12,000 for a 2- or 3-kilowatt (kW) system, respectively, in 1996. These costs represented two-thirds of the actual installed cost of $6 per watt at that time and assumed the remainder would be subsidized. The National Renewable Energy Laboratory (NREL) and OEC partnered to conduct a market assessment for GPV technology in Colorado. The study encompassed both qualitative and quantitative phases. The market assessment concluded that a market for residential GPV systems exists in Colorado today. That market is substantial enough for companies to successfully market PV systems to Colorado homeowners. These homeo wners appear ready to learn more, inform themselves, and actively purchase GPV systems. The present situation is highly advantageous to Colorado's institutions-primarily its state government and its utility companies, and also its homebuilders-if they are ready to move forward on GPV technology.

  15. A Market Assessment of Residential Grid-Tied PV Systems in Colorado: Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, B.; Coburn, T.

    2000-09-13

    This is the Executive Summary of a report that presents research done in response to a decision by the Colorado Governor's Office of Energy Conservation and Management (OEC) and Colorado utility companies to consider making residential grid-tied photovoltaic (PV) systems available in Colorado. The idea was to locate homeowners willing to pay the costs of grid-tied PV (GPV) systems without batteries--$8,000 or $12,000 for a 2- or 3-kilowatt (kW) system, respectively, in 1996. These costs represented two-thirds of the actual installed cost of $6 per watt at that time and assumed the remainder would be subsidized. The National Renewable Energy Laboratory (NREL) and OEC partnered to conduct a market assessment for GPV technology in Colorado. The study encompassed both qualitative and quantitative phases. The market assessment concluded that a market for residential GPV systems exists in Colorado today. That market is substantial enough for companies to successfully market PV systems to Colorado homeowners. These homeowners appear ready to learn more, inform themselves, and actively purchase GPV systems. The present situation is highly advantageous to Colorado's institutions--primarily its state government and its utility companies, and also its homebuilders--if they are ready to move forward on GPV technology.

  16. How PV system ownership can impact the market value of residential homes

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Geoffrey Taylor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jamie L. [Energy Sense Finance, LLC, Punta Gorda, FL (United States)

    2014-01-01

    There are multiple ways for a homeowner to obtain the electricity generating and savings benefits offered by a photovoltaic (PV) system. These include purchasing a PV system through various financing mechanisms, or by leasing the PV system from a third party with multiple options that may include purchase, lease renewal or PV system removal. The different ownership options available to homeowners presents a challenge to appraisal and real estate professionals during a home sale or refinance in terms of how to develop a value that is reflective of the PV systems operational characteristics, local market conditions, and lender and underwriter requirements. This paper presents these many PV system ownership options with a discussion of what considerations an appraiser must make when developing the contributory value of a PV system to a residential property.

  17. Effects of types of ventilation system on indoor particle concentrations in residential buildings.

    Science.gov (United States)

    Park, J S; Jee, N-Y; Jeong, J-W

    2014-12-01

    The objective of this study was to quantify the influence of ventilation systems on indoor particle concentrations in residential buildings. Fifteen occupied, single-family apartments were selected from three sites. The three sites have three different ventilation systems: unbalanced mechanical ventilation, balanced mechanical ventilation, and natural ventilation. Field measurements were conducted between April and June 2012, when outdoor air temperatures were comfortable. Number concentrations of particles, PM2.5 and CO2 , were continuously measured both outdoors and indoors. In the apartments with natural ventilation, I/O ratios of particle number concentrations ranged from 0.56 to 0.72 for submicron particles, and from 0.25 to 0.60 for particles larger than 1.0 μm. The daily average indoor particle concentration decreased to 50% below the outdoor level for submicron particles and 25% below the outdoor level for fine particles, when the apartments were mechanically ventilated. The two mechanical ventilation systems reduced the I/O ratios by 26% for submicron particles and 65% for fine particles compared with the natural ventilation. These results showed that mechanical ventilation can reduce exposure to outdoor particles in residential buildings. Results of this study confirm that mechanical ventilation with filtration can significantly reduce indoor particle levels compared with natural ventilation. The I/O ratios of particles substantially varied at the naturally ventilated apartments because of the influence of variable window opening conditions and unsteadiness of wind flow on the penetration of outdoor air particles. For better prediction of the exposure to outdoor particles in naturally ventilated residential buildings, it is important to understand the penetration of outdoor particles with variable window opening conditions. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Mammary Duct Ectasia

    Science.gov (United States)

    ... may worry that it's a sign of breast cancer, especially if you develop a hard lump around a milk duct affected by mammary duct ectasia. While it's important to get signs and symptoms checked out promptly, remember that mammary duct ectasia does not increase your risk of breast cancer. By Mayo ... . Mayo Clinic Footer Legal ...

  19. Performance of residential air-conditioning systems with flow maldistribution in fin-and-tube evaporators

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl; Brix, Wiebke; Elmegaard, Brian

    2011-01-01

    Refrigerant and airflow maldistribution in fin-and-tube evaporators for residential air-conditioning was investigated with numerical modeling. Fin-and-tube heat exchangers usually have a pre-defined circuitry. However, the objective in this study was to perform a generic investigation of each...... in this paper. The maldistribution sources of interest were: inlet liquid/vapor phase distribution, feeder tube bending and airflow distribution. The results show that maldistribution reduced the cooling capacity and the coefficient of performance of the system. In particular, different phase distribution...

  20. Promoting Residential Recycling: An Alternative Policy Based on a Recycling Reward System

    Directory of Open Access Journals (Sweden)

    Tongzhe Li

    2016-08-01

    Full Text Available This paper analyzes a reward system that uses a club good to promote recycling. In particular, we examine a context of incomplete information in which the administrator is unable to observe the resident’s attitude towards recycling. The results suggest that despite the lack of information, the administrator is able to induce all types of residents to recycle when the reward is sufficiently high. Furthermore, we show that education programs, technologies that help to reduce the residential recycling cost and penalties for garbage dumping are complementary tools that could also promote recycling.

  1. High efficiency battery converter with SiC devices for residential PV systems

    DEFF Research Database (Denmark)

    Pham, Cam; Teodorescu, Remus; Kerekes, Tamas

    2013-01-01

    The demand for high efficiency and higher power density is a challenge for Si-based semiconductors due to the physical characteristics of material. These can be overcome by employing wide-band-gap materials like SiC. This paper compares a second generator SiC MOSFETs against a normally-on Trench ...... JFETs and theirs performances in a high efficiency battery converter for residential photovoltaic systems. The prototypes are 3 kW converters with more than 98% efficiency and high simplicity and power density....

  2. Feasibility Study of Residential Grid-Connected Solar Photovoltaic Systems in the State of Indiana

    Science.gov (United States)

    Al-Odeh, Mahmoud

    This study aims to measure the financial viability of installing and using a residential grid-connected PV system in the State of Indiana while predicting its performance in eighteen geographical locations within the state over the system's expected lifetime. The null hypothesis of the study is that installing a PV system for a single family residence in the State of Indiana will not pay for itself within 25 years. Using a systematic approach consisting of six steps, data regarding the use of renewable energy in the State of Indiana was collected from the website of the US Department of Energy to perform feasibility analysis of the installation and use of a standard-sized residential PV system. The researcher was not able to reject the null hypothesis that installing a PV system for a single family residence in the State of Indiana will not pay for itself within 25 years. This study found that the standard PV system does not produce a positive project balance and does not pay for itself within 25 years (the life time of the system) assuming the average cost of a system. The government incentive programs are not enough to offset the cost of installing the system against the cost of the electricity that would not be purchased from the utility company. It can be concluded that the cost of solar PV is higher than the market valuation of the power it produces; thus, solar PV did not compete on the cost basis with the traditional competitive energy sources. Reducing the capital cost will make the standard PV system economically viable in Indiana. The study found that the capital cost for the system should be reduced by 15% - 56%.

  3. Solar heating and cooling of residential buildings: design of systems, 1980 edition

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This manual was prepared primarily for use in conducting a practical training course on the design of solar heating and cooling systems for residential and small office buildings, but may also be useful as a general reference text. The content level is appropriate for persons with different and varied backgrounds, although it is assumed that readers possess a basic understanding of heating, ventilating, and air-conditioning systems of conventional (non-solar) types. This edition is a revision of the manual with the same title, first printed and distributed by the US Government Printing Office in October 1977. The manual has been reorganized, new material has been added, and outdated information has been deleted. Only active solar systems are described. Liquid and air-heating solar systems for combined space and service water heating or service water heating are included. Furthermore, only systems with proven experience are discussed to any extent.

  4. Economic power schedule and transactive energy through an intelligent centralized energy management system for a DC residential distribution system

    DEFF Research Database (Denmark)

    Yue, Jingpeng; Hu, Zhijian; Li, Chendan

    2017-01-01

    is aligned with the command of the unit power schedule. In this work, a DC RDS is used as a case study to demonstrate the process, the RDS is associated with unit economic models, and a cost minimization objective is proposed that is to be achieved based on the real-time electrical price. The results show...... that the proposed framework and methods will help the targeted DC residential system to reduce the total cost and reach stability and efficiency....

  5. Integrated emissions control system for residential CWS furnace. Final report, September 20, 1989--March 20, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; McLarnon, C.

    1993-03-01

    One of the major obstacles to the successful development and commercialization of a coal-fired residential furnace is the need for a reliable, cost-effective emission control system. Tecogen is developing a novel, integrated control system to control NO{sub x}SO{sub 2}, and particulate emissions. At the heart of this system is a unique emissions control reactor for the control of SO{sub 2}. This reactor provides high sorbent particle residence time within the reactor while doing so in a very compact geometry. Final cleanup of any fine particulates exiting the reactor including respirable-sized particulates, is completed with the use of high efficiency bag filters. Under a previous contract with PETC (Contract No. DE-AC22-87PC79650), Tecogen developed a residential-scale Coal Water Slurry (CWS) combustor to control NO{sub x}emission. This combustor makes use of centrifugal forces, set up by a predominantly tangential flow field, to separate and confine larger unburned coal particles in the furnace upper chamber. Various partitions are used to retard the axial, downward flow of these particles, and thus maximize their residence time in the hottest section of the combustor. By operating this combustor under staged conditions, the local stoichiometry in the primary zone can be controlled in such a manner as to minimize NO{sub x} emission.

  6. An Economic Analysis of Residential Photovoltaic Systems with and without Energy Storage

    Science.gov (United States)

    Kizito, Rodney

    Residential photovoltaic (PV) systems serve as a source of electricity generation that is separate from the traditional utilities. Investor investment into residential PV systems provides several financial benefits such as federal tax credit incentives for installation, net metering credit from excess generated electricity added back to the grid, and savings in price per kilowatt-hour (kWh) from the PV system generation versus the increasing conventional utility price per kWh. As much benefit as stand-alone PV systems present, the incorporation of energy storage yields even greater benefits. Energy storage (ES) is capable of storing unused PV provided energy from daytime periods of high solar supply but low consumption. This allows the investor to use the stored energy when the cost of conventional utility power is high, while also allowing for excess stored energy to be sold back to the grid. This paper aims to investigate the overall returns for investor's investing in solely PV and ES-based PV systems by using a return of investment (ROI) economic analysis. The analysis is carried out over three scenarios: (1) residence without a PV system or ES, (2) residence with just a PV system, and (3) residence with both a PV system and ES. Due to the variation in solar exposure across the regions of the United States, this paper performs an analysis for eight of the top solar market states separately, accounting for the specific solar generation capabilities of each state. A Microsoft Excel tool is provided for computation of the ROI in scenario 2 and 3. A benefit-cost ration (BCR) is used to depict the annual economic performance of the PV system (scenario 2) and PV + ES system (scenario 3). The tool allows the user to adjust the variables and parameters to satisfy the users' specific investment situation.

  7. HVAC; Heating, Ventilation, Air Conditioning - Aerosol Duct Sealant

    Science.gov (United States)

    2016-09-01

    climatic conditions and different air distribution systems types. Data on thermal energy and fan power was collected before and after the duct sealant...Expeditionary Warfare Center. This technology internally seals leaks in air distribution ducts by injecting a fog of aerosolized sealant particles...into a pressurized duct system. The product keeps the particles suspended within the air stream. As the duct work is pressurized, the particles

  8. Technology Solutions Case Study: Optimizing Hydronic System Performance in Residential Applications, Ithaca, New York

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-11-01

    Condensing boiler technology has been around for many years and has proven to be a durable, reliable method of heating. Based on previous research efforts, however, it is apparent that these types of systems are not designed and installed to achieve maximum efficiency. For example, in order to protect their equipment in the field, manufacturers of low-mass condensing boilers typically recommend design strategies and components that ensure steady, high flow rates through the heat exchangers, such as primary-secondary piping, which ultimately result in decreased efficiency. There is also a significant lack of information for contractors on how to configure these systems to optimize overall efficiency. In response to these findings, researchers from Building America team Consortium for Advanced Residential Buildings worked with industry partners to develop hydronic system designs that would address these issues and result in higher overall system efficiencies and improved response times.

  9. Energy requirements of a multi-sensor based demand control ventilation system in residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Chul Seong, Nam; Min Hong, Sung; Won Yoon, Dong [Kyoungwon University, Seoul (Korea, Republic of); Jun Moon, Hyeun [Dankook University, Yongin (Korea, Republic of); Augenbroe, Godfried [Georgia Institute of Technology, Atlanta (United States)

    2010-07-01

    Nowadays, people spend most of their time indoors. Therefore indoor air quality is of high importance and the building regulation in Korea was revised to apply 0.7 air change rate in residential apartment housing. However residents do not often operate mechanical ventilation systems mainly due to their utility cost. The aim of this paper is to present a demand control ventilation (DCV) system which implements ventilation strategies to meet the ventilation requirements. An evaluation was conducted on both conventional ventilation and sensor based DCV systems to compare their energy requirements. The study showed that the use of the DCV system results in a better indoor air quality and a lower energy consumption than conventional ventilation. This paper highlighted that the Korean ventilation regulation is not enough to control the CO2 concentration and that the use of the sensor-based DCV would result in a healthier and more comfortable indoor environment.

  10. The Marriage of Residential Energy Codes and Rating Systems: Conflict Resolution or Just Conflict?

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Zachary T.; Mendon, Vrushali V.

    2014-08-21

    After three decades of coexistence at a distance, model residential energy codes and residential energy rating systems have come together in the 2015 International Energy Conservation Code. At the October, 2013, International Code Council’s Public Comment Hearing, a new compliance path based on an Energy Rating Index was added to the IECC. Although not specifically named in the code, RESNET’s HERS rating system is the likely candidate Index for most jurisdictions. While HERS has been a mainstay in various beyond-code programs for many years, its direct incorporation into the most popular model energy code raises questions about the equivalence of a HERS-based compliance path and the traditional IECC performance compliance path, especially because the two approaches use different efficiency metrics, are governed by different simulation rules, and have different scopes with regard to energy impacting house features. A detailed simulation analysis of more than 15,000 house configurations reveals a very large range of HERS Index values that achieve equivalence with the IECC’s performance path. This paper summarizes the results of that analysis and evaluates those results against the specific Energy Rating Index values required by the 2015 IECC. Based on the home characteristics most likely to result in disparities between HERS-based compliance and performance path compliance, potential impacts on the compliance process, state and local adoption of the new code, energy efficiency in the next generation of homes subject to this new code, and future evolution of model code formats are discussed.

  11. Techno-economic assessment and optimization of Stirling engine micro-cogeneration systems in residential buildings

    International Nuclear Information System (INIS)

    Alanne, Kari; Soederholm, Niklas; Siren, Kai; Beausoleil-Morrison, Ian

    2010-01-01

    Micro-cogeneration offers numerous potential advantages for the supply of energy to residential buildings in the sense of improved energy efficiency and reduced environmental burdens. To realize these benefits, however, such systems must reduce energy costs, primary energy consumption, and CO 2 emissions relative to conventional heating systems. In this paper, we search for optimized strategies for the integration of a Stirling engine-based micro-cogeneration system in residential buildings by comparing the performance of various system configurations and operational strategies with that of a reference system, i.e. hydronic heating and a low temperature gas boiler in standard and passive house constructions located in different climates. The IDA-ICE whole-building simulation program is employed with the Stirling engine micro-cogeneration model that was developed by IEA/ECBCS Annex 42. In this way the dynamic effects of micro-cogeneration devices, such as warm-ups and shutdowns, are accounted for. This study contributes to the research by addressing hourly changes in the fuel mix used for central electricity generation and the utilization of thermal exhaust through heat recovery. Our results suggest that an optimally operated micro-cogeneration system encompassing heat recovery and appropriate thermal storage would result in a 3-5% decrease in primary energy consumption and CO 2 emissions when compared to a conventional hydronic heating system. Moreover, this configuration is capable of delivering annual savings in all the combinations of electricity and fuel price between 0.05 and 0.15 Euro kW h -1 . As can be expected, these results are sensitive to the electrical energy supply mix, building type, and climate.

  12. Exergy characteristics of a ceiling-type residential air conditioning system operating under different climatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Arif [Dept. of Mechanical Engineering, Ceyhan Engineering Faculty, Cukurova University, Adana (Turkmenistan)

    2016-11-15

    In this study an energy and exergy analysis of a Ceiling-type residential air conditioning (CTRAC) system operating under different climatic conditions have been investigated for provinces within the different geographic regions of Turkey. Primarily, the hourly cooling load capacities of a sample building (Q{sub evap}) during the months of April, May, June, July, August and September were determined. The hourly total heat gain of the sample building was determined using the Hourly analysis program (HAP). The Coefficient of performance (COP), exergy efficiency (η) and exergy destruction (Ex{sub dest}) values for the whole system and for each component were obtained. The results showed that lower atmospheric temperature (T{sub atm}) influenced the performance of the system and each of its components.

  13. Impact of Scheduling Flexibility on Demand Profile Flatness and User Inconvenience in Residential Smart Grid System

    Directory of Open Access Journals (Sweden)

    Naveed Ul Hassan

    2013-12-01

    Full Text Available The objective of this paper is to study the impact of scheduling flexibility on both demand profile flatness and user inconvenience in residential smart grid systems. Temporal variations in energy consumption by end users result in peaks and troughs in the aggregated demand profile. In a residential smart grid, some of these peaks and troughs can be eliminated through appropriate load balancing algorithms. However, load balancing requires user participation by allowing the grid to re-schedule some of their loads. In general, more scheduling flexibility can result in more demand profile flatness, however the resulting inconvenience to users would also increase. In this paper, our objective is to help the grid determine an appropriate amount of scheduling flexibility that it should demand from users, based on which, proper incentives can be designed. We consider three different types of scheduling flexibility (delay, advance scheduling and flexible re-scheduling in flexible loads and develop both optimal and sub-optimal scheduling algorithms. We discuss their implementation in centralized and distributed manners. We also identify the existence of a saturation point. Beyond this saturation point, any increase in scheduling flexibility does not significantly affect the flatness of the demand profile while user inconvenience continues to increase. Moreover, full participation of all the households is not required since increasing user participation only marginally increases demand profile flatness.

  14. Detection and Quantification of Legionella pneumophila from Water Systems in Kuwait Residential Facilities

    Directory of Open Access Journals (Sweden)

    Qadreyah A. Al-Matawah

    2012-01-01

    Full Text Available The prevalence of Legionella pneumophilia in water systems of residential facilities in Kuwait was performed during the period from November 2007 to November 2011. A total of 204 water samples collected from faucets and showerheads in bathrooms (n = 82, taps in kitchens (n = 51, and water tanks (n = 71, from different locations of residential facilities in Kuwait were screened for Legionella pneumophila by the standard culture method and by real time polymerase chain reaction (RT-PCR. Out of the 204 samples, 89 (43.6% samples were positive for Legionella spp., 48 (23.5% samples were detected by the standard culture method, and 85 (41.7% were detected by RT-PCR. Of the culture positive Legionella samples, counts ranged between 10 to 2250 CFU/L. Serological typing of 48 Legionella isolates revealed that 6 (12.5% of these isolates belonged to Legionella pneumophila serogroup 1, 37 (77.1% isolates to Legionella pneumophila serogroup 3, and 1 isolate each (2.1% belonged to serogroups 4, 7, and 10. The minimum inhibitory concentration (MICs of the 46 environmental L. pneumophila isolates against the 10 antimicrobials commonly used for Legionella infection treatments were determined. Rifampicin was found to be the most active against L. pneumophila serogroups isolates in vitro.

  15. Comparison of Alcian Blue, Trypan Blue, and Toluidine Blue for Visualization of the Primo Vascular System Floating in Lymph Ducts

    Directory of Open Access Journals (Sweden)

    Da-Un Kim

    2015-01-01

    Full Text Available The primo vascular system (PVS, floating in lymph ducts, was too transparent to be observed by using a stereomicroscope. It was only detectable with the aid of staining dyes, for instance, Alcian blue, which was injected into the lymph nodes. Some dyes were absorbed preferentially by the PVS than the lymph wall. It remains a standing problem to know what dyes are absorbed better by the PVS than the lymph walls. Such information would be useful to unravel the biochemical properties of the PVS that are badly in need for obtaining large amount of PVS specimens. In the current work we tried two other familiar dyes which were used in PVS research before. We found that Trypan blue and toluidine blue did not visualize the PVS. Trypan blue was cleared by the natural washing. Toluidine blue did not stain the PVS, but it did leave stained spots in the lymph wall and its surrounding tissues, and it leaked out of the lymph wall to stain surrounding connective tissues. These completely different behaviors of the three dyes were found for the first time in the current work and provide valuable information to elucidate the mechanism through which some special dyes stained the PVS preferentially compared to the lymphatic wall.

  16. Integration of renewable energy systems to residential installations; Integracao de sistemas de energia renovavel a instalacoes residenciais

    Energy Technology Data Exchange (ETDEWEB)

    Marujo, Raquel; Simoes, Teresa; Estanqueiro, Ana [INETI - Instituto Nacional de Engenharia, Tecnologia e Inovacao (Portugal)

    2010-11-15

    The micro generation residential systems which produce energy from renewable sources need specific legislation and tools to identify the potentials and the feasibility to implant technological solutions adapted to urban environment. Examples of implementation of wind, photovoltaic and hybrid systems in a building are analyzed, with debates about energy and economic aspects.

  17. Modeling and optimization of a 1 kWe HT-PEMFC-based micro-CHP residential system

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2012-01-01

    A high temperature-proton exchange membrane (HT-PEMFC)-based micro-combined-heat-and-power (CHP) residential system is designed and optimized, using a genetic algorithm (GA) optimization strategy. The proposed system consists of a fuel cell stack, steam methane reformer (SMR) reactor, water gas s...

  18. Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Cold Climates

    Energy Technology Data Exchange (ETDEWEB)

    Building Industry Research Alliance (BIRA); Building Science Consortium (BSC); Consortium for Advanced Residential Buildings (CARB); Florida Solar Energy Center (FSEC); IBACOS; National Renewable Energy Laboratory (NREL)

    2006-08-01

    The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in Cold Climates on a cost-neutral basis.

  19. Layer-component-based communication stack framework for wireless residential control systems

    DEFF Research Database (Denmark)

    Torbensen, Rune; Hjorth, Theis

    2010-01-01

    This paper describes methods to lower the entry barrier for creating products that interoperate in the emerging heterogeneous residential control network domain. For designing reconfigurable, layer-component-based communication stacks, a flexible framework is proposed that supports several types ...... shown how the framework facilitates fast prototyping and makes developing secure wireless control systems less complex....... of nodes such as bridges, controllers, sensor/actuators - as well as secure communication between them. A special messaging system facilitates inter-component communication, and a Virtual Port Service protocol enables resource addressing. The end-devices in the heterogeneous network are made accessible...... on a common IP infrastructure, regardless of individual wireless technology. Legacy home automation devices are also supported. A prototype has been implemented on multiple resource-constrained hardware platforms, to demonstrate that the solution is both feasible for low-cost devices and portable. It has been...

  20. Layer-component-based communication stack framework for wireless residential control systems

    DEFF Research Database (Denmark)

    Torbensen, R.; Hjorth, Theis S.

    2011-01-01

    This paper describes methods to lower the entry barrier for creating products that interoperate in the emerging heterogeneous residential control network domain. For designing reconfigurable, layer-component-based communication stacks, a flexible framework is proposed that supports several types ...... shown how the framework facilitates fast prototyping and makes developing secure wireless control systems less complex....... of nodes such as bridges, controllers, sensor/actuators – as well as secure communication between them. A special messaging system facilitates inter-component communication, and a Virtual Port Service protocol enables resource addressing. The end-devices in the heterogeneous network are made accessible...... on a common IP infrastructure, regardless of individual wireless technology. Legacy home automation devices are also supported. A prototype has been implemented on multiple resource-constrained hardware platforms, to demonstrate that the solution is both feasible for low-cost devices and portable. It has been...

  1. Public Response to Residential Grid-Tied PV Systems in Colorado: A Qualitative Market Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, Barbara C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Buhrmann, Jan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1998-07-01

    The early adopters of residential grid-tied photovoltaics (PV) have complex motivations to pay today's costs, including altruistic, environmental, and financial reasons. Focused interviews were conducted with a self-selected purposive sample interested in purchasing 2-kW or 3-kW PV systems with an installed cost of $8,000 to $12,000. The sample tended to be men or married couples ranging in age from their early thirties to their mid-eighties; professionals, managers, or small business owners; relatively financially secure, with experience with energy efficiency and renewable energy. Product attributes they preferred were net metering, warranties, guarantees, utility financing, maintenance, an option to own or lease, a battery option, and an aesthetically pleasing system. Potential PV customers needed more information before making a purchase decision.

  2. Prioritized rule based load management technique for residential building powered by PV/battery system

    Directory of Open Access Journals (Sweden)

    T.R. Ayodele

    2017-06-01

    Full Text Available In recent years, Solar Photovoltaic (PV system has presented itself as one of the main solutions to the electricity poverty plaguing the majority of buildings in rural communities with solar energy potential. However, the stochasticity associated with solar PV power output owing to vagaries in weather conditions is a major challenge in the deployment of the systems. This study investigates approach for maximizing the benefits of a Stand-Alone Photovoltaic-Battery (SAPVB system via techniques that provide for optimum energy gleaning and management. A rule-based load management scheme is developed and tested for a residential building. The approach allows load prioritizing and shifting based on certain rules. To achieve this, the residential loads are classified into Critical Loads (CLs and Uncritical Loads (ULs. The CLs are given higher priority and therefore are allowed to operate at their scheduled time while the ULs are of less priority, hence can be shifted to a time where there is enough electric power generation from the PV arrays rather than the loads being operated at the time period set by the user. Four scenarios were created to give insight into the applicability of the proposed rule based load management scheme. The result revealed that when the load management technique is not utilized as in the case of scenario 1 (Base case, the percentage satisfaction of the critical and uncritical loads by the PV system are 49.8% and 23.7%. However with the implementation of the load management scheme in scenarios 2, 3 and 4, the percentage satisfaction of the loads (CLs, ULs are (93.8%, 74.2%, (90.9%, 70.1% and (87.2%, 65.4% for scenarios 2, 3 and 4, respectively.

  3. U.S. Photovoltaic Prices and Cost Breakdowns. Q1 2015 Benchmarks for Residential, Commercial, and Utility-Scale Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Davidson, Carolyn [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ardani, Kristen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    The price of photovoltaic (PV) systems in the United States (i.e., the cost to the system owner) has continued to decline across all major market sectors. This report provides a Q1 2015 update regarding the prices of residential, commercial, and utility scale PV systems, based on an objective methodology that closely approximates the book value of a PV system. Several cases are benchmarked to represent common variations in business models, labor rates, and system architecture choice. We estimate a weighted-average cash purchase price of $3.09/W for residential scale rooftop systems, $2.15/W for commercial scale rooftop systems, $1.77/W for utility scale systems with fixed mounting structures, and $1.91/W for utility scale systems using single-axis trackers. All systems are modeled assuming standard-efficiency, polycrystalline-silicon PV modules, and further assume installation within the United States.

  4. Transition duct with divided upstream and downstream portions

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Maldonado, Jaime Javier; Dillard, Daniel Jackson; Flanagan, James Scott

    2015-07-14

    Turbine systems are provided. In one embodiment, a turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion extending from the inlet and a downstream portion extending from the outlet. The turbine system further includes a rib extending from an outer surface of the duct passage, the rib dividing the upstream portion and the downstream portion.

  5. Cirrhosis induced by bile duct ligation alleviates acetic acid intestinal damages in rats: Involvements of nitrergic and opioidergic systems.

    Science.gov (United States)

    Rahimi, Nastaran; Hassanipour, Mahsa; Allahabadi, Narges Sistany; Sabbaghziarani, Fatemeh; Yazdanparast, Maryam; Dehpour, Ahmadreza

    2017-11-22

    Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats. Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction. Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg). Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  6. Right/left symmetry of the intrahepatic distribution and terminology of the hepatic artery proper and the intrahepatic bile duct system: proposals to revise the Terminologia Anatomica.

    Science.gov (United States)

    Matusz, Petru

    2011-01-01

    Anatomical terminology is the foundation of medical terminology and it is important that doctors and scientists throughout the world use the same name for each structure. It is also important that the anatomical terms for a specific anatomical structure are presented in a logical order. To eliminate confusion, it is crucial that the same name is not attributed to two or more anatomical elements. However, the term artery of caudate lobe is used for two distinct anatomic elements with different origins (right/left branch of hepatic proper artery). Also, I draw attention to the incorrect positioning of right/left duct of caudate lobe in the description of terms homologated for the intrahepatic bile duct system. These proposals to amend the terminology in the liver anatomy are a necessary step in the evolution of the Terminologia Anatomica.

  7. Real-time Modelling, Diagnostics and Optimised MPPT for Residential PV Systems

    DEFF Research Database (Denmark)

    Sera, Dezso

    and generic nature, and has the benefit of also being efficient in fast-changing conditions. Furthermore, the algorithm has been successfully implemented on a commercial PV inverter, currently on the market. In Chapter 3, an overview of the existing mathematical models used to describe the electrical...... responsible for yield-reduction of residential photovoltaic systems. Combining the model calculations with measurements, a method to detect changes in the panels’ series resistance based on the slope of the I − V curve in the vicinity of open-circuit conditions and scaled to Standard Test Conditions (STC......) , is proposed. The results confirm the benefits of the proposed method in terms of robustness to irradiance changes and to partial shadows. In order to detect partial shadows on PV panels, a method based on equivalent thermal voltage (Vt) monitoring is proposed. Vt is calculated using the simplified three...

  8. Analysis of flow maldistribution in fin-and-tube evaporators for residential air-conditioning systems

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl

    validated and showed that a slip flow model need be used. A test case 8.8 kW residential air-conditioning system with R410A as refrigerant is chosen as baseline for the numerical investigations, and the simulations are performed at standard rating conditions from ANSI/AHRI Standard 210/240 (2008...... cases are standard tube circuitry designs and these results are thus tube circuitry specific. In addition, a novel method of compensating flow maldistribution is analyzed, i.e. the discontinuous liquid injection principle. The method is based upon the recently developed EcoFlowTM valve by Danfoss A...... profile across the A-coil evaporator was predicted by means of CFD simulation software STAR-CD 3.26 (2005) and applied in the numerical model. The main reason for the better face split evaporator performance at uniform conditions or when compensating, is that the superheated "weak" zones with low UA...

  9. The study of residential life support environment system to initiate policy on sustainable simple housing

    Science.gov (United States)

    Siahaan, N. M.; Harahap, A. S.; Nababan, E.; Siahaan, E.

    2018-02-01

    This study aims to initiate sustainable simple housing system based on low CO2 emissions at Griya Martubung I Housing Medan, Indonesia. Since it was built in 1995, between 2007 until 2016 approximately 89 percent of houses have been doing various home renewal such as restoration, renovation, or reconstruction. Qualitative research conducted in order to obtain insights into the behavior of complex relationship between various components of residential life support environment that relates to CO2 emissions. Each component is studied by conducting in-depth interviews, observation of the 128 residents. The study used Likert Scale to measure residents’ perception about components. The study concludes with a synthesis describing principles for a sustainable simple housing standard that recognizes the whole characteristics of components. This study offers a means for initiating the practice of sustainable simple housing developments and efforts to manage growth and preserve the environment without violating social, economics, and ecology.

  10. The Application Modular Floating Pontoon to Support Floods Disaster Evacuation System in Heavy Populated Residential Area

    Directory of Open Access Journals (Sweden)

    Ahmad Fauzan Zakki

    2014-10-01

    Full Text Available During floods disaster in the heavy populated residential area, the lack of existing life saving appliances system such as rubber boat and wooden boat were not able to evacuate the disaster victims spontaneously in mass. The condition might be explained since the rubber boat and wooden boat have limited occupant capacity. Based on the conditions, the main objectives of the research are focused on the evaluation of the application of modular floating pontoon as multipurpose floating equipment to support floods disaster evacuation process. The investigation of the modular floating pontoon performance such as hydrostatics characteristics, the equilibrium condition and the intact stability was studied using strip theory and Krylov’s method. Furthermore, the strength analysis of the modular floating pontoon structure was calculated using finite element method. The results show that the modular floating pontoon is reliable to support the evacuation process.

  11. Model documentation report: Residential sector demand module of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    This report documents the objectives, analytical approach, and development of the National Energy Modeling System (NEMS) Residential Sector Demand Module. The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, and FORTRAN source code. This document serves three purposes. First, it is a reference document that provides a detailed description for energy analysts, other users, and the public. Second, this report meets the legal requirement of the Energy Information Administration (EIA) to provide adequate documentation in support of its statistical and forecast reports according to Public Law 93-275, section 57(b)(1). Third, it facilitates continuity in model development by providing documentation from which energy analysts can undertake model enhancements, data updates, and parameter refinements.

  12. A Residential Distributed-Generating System with Photovoltaic Cells and Hydrogen-Storage Type Fuel Cells and its Operational Scheme

    Science.gov (United States)

    Machida, Yuuki; Funabiki, Shigeyuki

    Output power in photovoltaic systems changes steeply with the change of the solar irradiance and overall PV temperature. The change of output power has influence on the electric power quality of the system. This paper proposes a novel operational scheme of the residential distributed power generation system using solar cells and hydrogen-storage type fuel cells. In order to level the output power which changes steeply the fuel cells are connected to the PV system in parallel. Thus the generated power of all the system can be leveled. However, the hydrogen is required in order to generate electricity by the fuel cells. Therefore, the electrolyzer which is hydrogen manufacturing equipment is installed in the system. It is confirmed by the simulation that the distributed power generation system operates according to the proposed operational scheme and its system is available for residential supplies.

  13. Efficiency Analysis of Independent and Centralized Heating Systems for Residential Buildings in Northern Italy

    Directory of Open Access Journals (Sweden)

    Fabio Rinaldi

    2011-11-01

    Full Text Available The primary energy consumption in residential buildings is determined by the envelope thermal characteristics, air change, outside climatic data, users’ behaviour and the adopted heating system and its control. The new Italian regulations strongly suggest the installation of centralized boilers in renovated buildings with more than four apartments. This work aims to investigate the differences in primary energy consumption and efficiency among several independent and centralized heating systems installed in Northern Italy. The analysis is carried out through the following approach: firstly building heating loads are evaluated using the software TRNSYS® and, then, heating system performances are estimated through a simplified model based on the European Standard EN 15316. Several heating systems have been analyzed, evaluating: independent and centralized configurations, condensing and traditional boilers, radiator and radiant floor emitters and solar plant integration. The heating systems are applied to four buildings dating back to 2010, 2006, 1960s and 1930s. All the combinations of heating systems and buildings are analyzed in detail, evaluating efficiency and primary energy consumption. In most of the cases the choice between centralized and independent heating systems has minor effects on primary energy consumption, less than 3%: the introduction of condensing technology and the integration with solar heating plant can reduce energy consumption by 11% and 29%, respectively.

  14. The demand function for residential heat through district heating system and its consumption benefits in Korea

    International Nuclear Information System (INIS)

    Lim, Seul-Ye; Kim, Hyo-Jin; Yoo, Seung-Hoon

    2016-01-01

    The demand for residential heat (RH) through a district heating system (DHS) has been and will be expanded in Korea due to its better performance in energy efficiency and the abatement of greenhouse gas emissions than decentralized boilers. The purposes of this paper are two-fold. The first is to obtain the demand function for DHS-based RH in Korea and investigate the price and income elasticities of the demand employing the quarterly data covering the period 1988–2013. The short-run price and income elasticities are estimated as −0.700 and 0.918, respectively. Moreover, the long-run elasticities are −1.253 and 1.642, respectively. The second purpose is to measure the consumption benefits of DHS-based-RH employing the economic theory that they are the sum of the actual payment and consumer surplus for the consumption. Considering that the average price and estimated consumer surplus of the DHS-based RH use in 2013 are computed to be KRW 87,870 (USD 84.1) and KRW 62,764 (USD 60.1) per Gcal, the consumption benefits of the DHS-based RH are calculated to be KRW 150,634 (USD 144.2) per Gcal. This information can be beneficially utilized to conduct an economic feasibility study for a new DHS project related to RH supply. - Highlights: • Demand for residential heat (RH) from district heating system (DHS) is expanding. • We estimate the demand function for and consumption benefits of DHS-based RH. • Short-run price and income elasticities are −0.700 and 0.918, respectively. • Long-run price and income elasticities are −1.253 and 1.642, respectively. • Consumption benefits of DHS-based RH are KRW 150,634 (USD 144.2) per Gcal.

  15. Motivational factors influencing the homeowners’ decisions between residential heating systems: An empirical analysis for Germany

    International Nuclear Information System (INIS)

    Michelsen, Carl Christian; Madlener, Reinhard

    2013-01-01

    Heating demand accounts for a large fraction of the overall energy demand of private households in Germany. A better understanding of the adoption and diffusion of energy-efficient and renewables-based residential heating systems (RHS) is of high policy relevance, particularly against the background of climate change, security of energy supply and increasing energy prices. In this paper, we explore the multi-dimensionality of the homeowners’ motivation to decide between competing RHS. A questionnaire survey (N=2440) conducted in 2010 among homeowners who had recently installed a RHS provides the empirical foundation. Principal component analysis shows that 25 items capturing different adoption motivations can be grouped around six dimensions: (1) cost aspects, (2) general attitude towards the RHS, (3) government grant, (4) reactions to external threats (i.e., environmental or energy supply security considerations), (5) comfort considerations, and (6) influence of peers. Moreover, a cluster analysis with the identified motivational factors as segmentation variables reveals three adopter types: (1) the convenience-oriented, (2) the consequences-aware, and (3) the multilaterally-motivated RHS adopter. Finally, we show that the influence of the motivational factors on the adoption decision also differs by certain characteristics of the homeowner and features of the home. - Highlights: ► Study of the multi-dimensionality of the motivation to adopt residential heating systems (RHS). ► Principal component and cluster analysis are applied to representative survey data for Germany. ► Motivation has six dimensions, including rational decision-making and emotional factors. ► Adoption motivation differs by certain characteristics of the homeowner and of the home. ► Many adopters are driven by existing habits and perceptions about the convenience of the RHS

  16. IMPROVING THE SYSTEM OF MORTGAGE CREDITING OF RESIDENTIAL REAL ESTATE IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Alexander Goloven

    2015-11-01

    Full Text Available The purpose of the article is to improve the system of mortgage crediting of residential real estate in Ukraine. Mortgage lending appeared in Ukraine in the early XVII century, today the actual problem is a small percentage of the banking book long-term mortgage loans, because banks, on the one hand, tend to rotate without the risk of short-term funds, another potential borrower of these loans, unfortunately, is not creditworthy. However, despite the risks, this banking product is a significant factor in the redistribution and accumulation of funds, the transformation of private savings into investment resources, the problem of housing, but also contributes to the stabilization of the economy in the country as a whole. Functioning and the distribution of mortgage capital, the possible financial risks, the interaction of the mortgage market by the financial, investment and monetary Affairs, leads to a certain complexity of the mechanism of functioning of the mortgage market of Ukraine in general. The relevance of this topic not only in the development of the housing market, but also the feasibility studies for the development of this issue. We present an analysis of the institutional environment of mortgage lending residential real estate, which gave an opportunity to identify and define the environment of modern residential real estate market, its relationship with other markets. Methodology. The survey is based on institutional structure of the mortgage market that has evolved independently of other structures, independently within country under the influence of specific socio-economic environment and economic policy. Results of the survey showed that mortgage lending can be providing the borrower with some free services, such as: long-term deposit on favorable terms, notary services, insurance, discounts on bank services, providing services to the bank and the developer, given appropriate training of the borrower and so forth. Practical

  17. Efficiency Analyses of a DC Residential Power Distribution System for the Modern Home

    Directory of Open Access Journals (Sweden)

    GELANI, H. E.

    2015-02-01

    Full Text Available The electric power system started as DC back in the nineteenth century. However, the DC paradigm was soon ousted by AC due to inability of DC to change its voltage level. Now, after many years, with the development of power electronic converters capable of stepping-up and down DC voltage and converting it to-and-from AC, DC appears to be challenging AC and attempting a comeback. We now have DC power generation by solar cells, fuel cells and wind farms, DC power transmission in the form of HVDC (High Voltage DC transmission, DC power utilization by various modern electronic loads and DC power distribution that maybe regarded as still in research phase. This paper is an attempt to investigate feasibility of DC in the distribution portion of electrical power system. Specifically, the efficiency of a DC distribution system for residential localities is determined while keeping in view the concept of daily load variation. The aim is to bring out a more practical value of system efficiency as the efficiencies of DC/DC converters making up the system vary with load variation. This paper presents the modeling and simulation of a DC distribution system and efficiency results for various scenarios are presented.

  18. Investigation of Energy and Environmental Potentials of a Renewable Trigeneration System in a Residential Application

    Directory of Open Access Journals (Sweden)

    Eun-Chul Kang

    2016-09-01

    Full Text Available Micro polygeneration utilizing renewable energy is a suitable approach to reduce energy consumption and carbon emission by offering high-efficiency performance, offsetting the need for centrally-generated grid electricity and avoiding transmission/distribution losses associated with it. This paper investigates the energy and environmental potential of a renewable trigeneration system in a residential application under Incheon (Korea and Ottawa (Canada weather conditions. The trigeneration system consists of a ground-to-air heat exchanger (GAHX, photovoltaic thermal (PVT panels and an air-to-water heat pump (AWHP. The study is performed by simulations in TRNSYS (Version 17.02 environment. The performance of the trigeneration system is compared to a reference conventional system that utilizes a boiler for space and domestic hot water heating and a chiller for space cooling. Simulation results showed substantial annual primary energy savings from the renewable trigeneration system in comparison to the reference system—45% for Incheon and 42% for Ottawa. The CO2eq emission reduction from the renewable trigeneration system is also significant, standing at 43% for Incheon and 82% for Ottawa. Furthermore, trigeneration systems’ capability to generate electricity and thermal energy at the point of use is considered as an attractive option for inclusion in the future smart energy network applications.

  19. Distributed photovoltaic generation in residential distribution systems: Impacts on power quality and anti-islanding

    Science.gov (United States)

    Mitra, Parag

    The past few decades have seen a consistent growth of distributed PV sources. Distributed PV, like other DG sources, can be located at or near load centers and provide benefits which traditional generation may lack. However, distribution systems were not designed to accommodate such power generation sources as these sources might lead to operational as well as power quality issues. A high penetration of distributed PV resources may lead to bi-directional power flow resulting in voltage swells, increased losses and overloading of conductors. Voltage unbalance is a concern in distribution systems and the effect of single-phase residential PV systems on voltage unbalance needs to be explored. Furthermore, the islanding of DGs presents a technical hurdle towards the seamless integration of DG sources with the electricity grid. The work done in this thesis explores two important aspects of grid inte-gration of distributed PV generation, namely, the impact on power quality and anti-islanding. A test distribution system, representing a realistic distribution feeder in Arizona is modeled to study both the aforementioned aspects. The im-pact of distributed PV on voltage profile, voltage unbalance and distribution sys-tem primary losses are studied using CYMDIST. Furthermore, a PSCAD model of the inverter with anti-island controls is developed and the efficacy of the anti-islanding techniques is studied. Based on the simulations, generalized conclusions are drawn and the problems/benefits are elucidated.

  20. Residential PV system users' perception of profitability, reliability, and failure risk: An empirical survey in a local Japanese municipality

    International Nuclear Information System (INIS)

    Mukai, Toshihiro; Kawamoto, Shishin; Ueda, Yuzuru; Saijo, Miki; Abe, Naoya

    2011-01-01

    Although previous studies have addressed the reliability of residential PV systems in order to improve the dissemination of the systems among individual users and societies, few have examined users' perception of their own PV systems, which might contain solutions to firmly establish the system into society. First, the present paper examined the extent to which residential PV system users understand specification, reliability, and failure risk of their own systems. Second, causal factors affecting users' satisfaction with PV systems were examined. By analyzing data collected in Kakegawa City, this paper revealed that users did not appropriately understand the basic specifications of their residential PV systems, and in particular, the fact that the systems sometimes failed and therefore needed proper maintenance. Furthermore, a strong causal relationship between users' expectations of financial return from the system and their level of satisfaction was confirmed empirically. These results suggested that excessive focus on profitability and relatively low interest in the systems' reliability and failure risk should be addressed more to avoid problems that could potentially hamper the establishment of this technology into society. - Highlights: → We examined PV users' perception of its specification, reliability, and failure risk. → Data for analysis were collected by questionnaire survey in a Japanese local municipality. → We revealed users did not appropriately understand the basic specifications. → A strong causal relationship between users' expectations of financial return and their level of satisfaction was confirmed empirically.

  1. Research, Development and Demonstration of Micro-CHP System for Residential Applications

    Energy Technology Data Exchange (ETDEWEB)

    Karl Mayer

    2010-03-31

    ECR International and its joint venture company, Climate Energy, are at the forefront of the effort to deliver residential-scale combined heat and power (Micro-CHP) products to the USA market. Part of this substantial program is focused on the development of a new class of steam expanders that offers the potential for significantly lower costs for small-scale power generation technology. The heart of this technology is the scroll expander, a machine that has revolutionized the HVAC refrigerant compressor industry in the last 15 years. The liquid injected cogeneration (LIC) technology is at the core of the efforts described in this report, and remains an excellent option for low cost Micro-CHP systems. ECR has demonstrated in several prototype appliances that the concept for LIC can be made into a practical product. The continuing challenge is to identify economical scroll machine designs that will meet the performance and endurance requirements needed for a long life appliance application. This report describes the numerous advances made in this endeavor by ECR International. Several important advances are described in this report. Section 4 describes a marketing and economics study that integrates the technical performance of the LIC system with real-world climatic data and economic analysis to assess the practical impact that different factors have on the economic application of Micro-CHP in residential applications. Advances in the development of a working scroll steam expander are discussed in Section 5. A rigorous analytical assessment of the performance of scroll expanders, including the difficult to characterize impact of pocket to pocket flank leakage, is presented in Section 5.1. This is followed with an FEA study of the thermal and pressure induced deflections that would result from the normal operation of an advanced scroll expander. Section 6 describes the different scroll expanders and test fixtures developed during this effort. Another key technical

  2. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

  3. The trigger matters: The decision-making process for heating systems in the residential building sector

    International Nuclear Information System (INIS)

    Hecher, Maria; Hatzl, Stefanie; Knoeri, Christof; Posch, Alfred

    2017-01-01

    As heat demand of buildings accounts for a significant amount of final energy use and related carbon emissions, it’s important to gain insights into the homeowners’ decision-making processes and to identify factors determining the choice of heating systems. In this study, data was collected in an online survey carried out in 2015, from private homeowners of existing and newly built single and double-family houses in Austria who had invested in a new heating system within the last ten years (N=484). In contrast to previous studies, this study specifically investigates the triggers behind homeowner decisions to invest in a new heating system (e.g. problem, opportunity, or new building situation). Results of binary logistic regression analysis show that subsidies for heating system tabinvestments and infrastructural adjustments reveal to be most effective for homeowners in problem situations to foster alternative heating systems. For homeowners in opportunity situations (e.g. building refurbishment), in addition operational convenience appears to be important. For new buildings, the main barriers for alternative heating system adoption were found in the positive perception of fuel supply security and feasibility of fossil systems. Thus, the use of trigger-specific policy measures is proposed to foster alternative heating systems in the residential building sector. - Highlights: • Homeowners’ triggers determine heating system adoption decisions. • It is crucial to reach homeowners early enough to avoid problem situations. • For problem-triggered homeowners, subsidies are most effective. • Opportunity-triggered homeowners prefer alternative heating systems. • Opportunity-triggered homeowners need solid decision basis for technology comparison.

  4. Research, Development and Demonstration of Micro-CHP Systems for Residential Applications - Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Robert A. Zogg

    2011-03-14

    The objective of the Micro-CHP Phase I effort was to develop a conceptual design for a Micro-CHP system including: Defining market potential; Assessing proposed technology; Developing a proof-of-principle design; and Developing a commercialization strategy. TIAX LLC assembled a team to develop a Micro-CHP system that will provide electricity and heating. TIAX, the contractor and major cost-share provider, provided proven expertise in project management, prime-mover design and development, appliance development and commercialization, analysis of residential energy loads, technology assessment, and market analysis. Kohler Company, the manufacturing partner, is a highly regarded manufacturer of standby power systems and other residential products. Kohler provides a compellingly strong brand, along with the capabilities in product development, design, manufacture, distribution, sales, support, service, and marketing that only a manufacturer of Kohler's status can provide. GAMA, an association of appliance and equipment manufacturers, provided a critical understanding of appliance commercialization issues, including regulatory requirements, large-scale market acceptance issues, and commercialization strategies. The Propane Education & Research Council, a cost-share partner, provided cost share and aided in ensuring the fuel flexibility of the conceptual design. Micro-CHP systems being commercialized in Europe and Japan are generally designed to follow the household thermal load, and generate electricity opportunistically. In many cases, any excess electricity can be sold back to the grid (net metering). These products, however, are unlikely to meet the demands of the U.S. market. First, these products generally cannot provide emergency power when grid power is lost--a critical feature to market success in the U.S. Even those that can may have insufficient electric generation capacities to meet emergency needs for many U.S. homes. Second, the extent to which net

  5. Instructor's Manual for Teaching and Practical Courses on Design of Systems and Sizing, Installation and Operation of Systems for Solar Heating and Cooling of Residential Buildings.

    Science.gov (United States)

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    Presented are guidelines for instructors of two courses in the design, installation, and operation of solar heating and cooling systems. These courses are: (1) Design of Systems, and (2) Sizing, Installation, and Operation of Systems. Limited in scope to active solar systems for residential buildings, these courses place primary emphasis upon…

  6. Radiant floor cooling coupled with dehumidification systems in residential buildings: A simulation-based analysis

    International Nuclear Information System (INIS)

    Zarrella, Angelo; De Carli, Michele; Peretti, Clara

    2014-01-01

    Highlights: • The floor radiant cooling in a typical apartment is analyzed. • Dehumidification devices, fan-coil and mechanical ventilation are compared. • The results are analyzed in terms of both thermal comfort and energy consumption. • The energy consumption of the dehumidifiers is higher than that of other systems. • The mechanical ventilation decreases the moisture level better than other systems. - Abstract: The development of radiant cooling has stimulated an interest in new systems based on coupling ventilation with radiant cooling. However, radiant cooling systems may cause condensation to form on an active surface under warm and humid conditions during the cooling season. This phenomenon occurs when surface temperature falls below dew point. To prevent condensation, air humidity needs to be reduced with a dehumidification device or a mechanical ventilation system. There are two main options to achieve this. The first is to use dehumidification devices that reduce humidity, but are not coupled with ventilation, i.e. devices that handle room air and leave air change to infiltrations. The second is to combine a mechanical ventilation system with dehumidifying finned coils. This study analyzes the floor radiant cooling of a typical residential apartment within a multi-storey building in three Italian climate zones by means of a detailed simulation tool. Five systems were compared in terms of both indoor thermal comfort and energy consumption: radiant cooling without dehumidification; radiant cooling with a soft dehumidification device; radiant cooling with a dehumidification device which also supplies sensible cooling; radiant cooling coupled with fan coils; and radiant cooling with a mechanical ventilation system which dehumidifies and cools

  7. Residential on site solar heating systems: a project evaluation using the capital asset pricing model

    Energy Technology Data Exchange (ETDEWEB)

    Schutz, S.R.

    1978-12-01

    An energy source ready for immediate use on a commercial scale is solar energy in the form of On Site Solar Heating (OSSH) systems. These systems collect solar energy with rooftop panels, store excess energy in water storage tanks and can, in certain circumstances, provide 100% of the space heating and hot water required by the occupants of the residential or commercial structure on which the system is located. Such systems would take advantage of a free and inexhaustible energy source--sunlight. The principal drawback of such systems is the high initial capital cost. The solution would normally be a carefully worked out corporate financing plan. However, at the moment it is individual homeowners and not corporations who are attempting to finance these systems. As a result, the terms of finance are excessively stringent and constitute the main obstacle to the large scale market penetration of OSSH. This study analyzes the feasibility of OSSH as a private utility investment. Such systems would be installed and owned by private utilities and would displace other investment projects, principally electric generating plants. The return on OSSH is calculated on the basis of the cost to the consumer of the equivalent amount of electrical energy that is displaced by the OSSH system. The hurdle rate for investment in OSSH is calculated using the Sharpe--Lintner Capital Asset Pricing Model. The results of this study indicate that OSSH is a low risk investment having an appropriate hurdle rate of 7.9%. At this rate, OSSH investment appears marginally acceptable in northern California and unambiguously acceptable in southern California. The results also suggest that utility investment in OSSH should lead to a higher degree of financial leverage for utility companies without a concurrent deterioration in the risk class of utility equity.

  8. Developing Innovative Wall Systems that Improve Hygrothermal Performance of Residential Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Robert Tichy; Chuck Murray

    2006-05-31

    This document serves as the Topical Report documenting work completed by Washington State University (WSU) under U.S. Department of Energy Grant, Developing Innovative Wall Systems that Improve Hygrothermal Performance of Residential Buildings. This project was conducted in collaboration with Oak Ridge National Laboratory (ORNL), and includes the participation of several industry partners including Weyerhaeuser, APA - The Engineered Wood Association, CertainTeed Corporation and Fortifiber. This document summarizes work completed by Washington State University August 2002 through June 2006. WSU's primary experimental role is the design and implementation of a field testing protocol that monitored long term changes in the hygrothermal response of wall systems. During the project period WSU constructed a test facility, developed a matrix of test wall designs, constructed and installed test walls in the test facility, installed instrumentation in the test walls and recorded data from the test wall specimens. Each year reports were published documenting the hygrothermal response of the test wall systems. Public presentation of the results was, and will continue to be, made available to the building industry at large by industry partners and the University.

  9. Projected Benefits of New Residential Evaporative Cooling Systems: Progress Report #2

    Energy Technology Data Exchange (ETDEWEB)

    Kutscher, C.; Eastment, M.; Hancock, E.; Reeves, P.

    2006-10-01

    The use of conventional evaporative cooling has rapidly declined in the United States despite the fact that it has high potential for energy savings in dry climates. Evaporative systems are very competitive in terms of first cost and provide significant reductions in operating energy use, as well as peak-load reduction benefits. Significant market barriers still remain and can be addressed through improved systems integration. This report investigates the first of these approaches, exploring innovative components. The U.S. Department of Energy (DOE) Building America research teams are investigating the use of two promising new pieces of residential cooling equipment that employ evaporative cooling as a part of their system design. The OASys unit, which is a combination of direct and indirect evaporative cooling stages developed by Davis Energy Group (DEG) and manufactured by Speakman CRS, is used to ultimately provide outside air to the living space. The outdoor air provided is indirectly and directly evaporatively cooled in two stages to a condition that can be below the wet-bulb (wb) temperature of the outside air, thus outperforming a conventional single-stage direct evaporative cooler.

  10. Wood pellet use in Sweden. A systems approach to the residential sector

    International Nuclear Information System (INIS)

    Vinterbaeck, Johan

    2000-01-01

    This empirically based thesis deals with a biofuel market in a systems context with focus on Sweden. Fuel pellets is a new consumer market for wood products. Initially used mainly by large-scale heating plants, wood pellets expanded into the Swedish residential heating market in the mid 1990s. The overall aim of this work is to provide a deeper understanding of the system for small-scale use of densified wood fuels. The objective was to provide a mapping and logistic analysis of fuel and delivery chains primarily for wood pellets. The description includes both technical as well as economic and organisational aspects. The thesis in particular investigates (i) experience from practical densification operations in the past, (ii) wood pellet retailers in Sweden, (iii) wood pellet consumers in Austria, Sweden and the United States, (iv) imports of wood pellets, and (v) forecasting of pellet consumption and inventory management for wood pellet distributors. Previous international studies revealed that the availability of cheap raw materials for fuel production and the price and availability of the most important competing fuels: coal, oil and natural gas were important factors that have guided production and use of densified wood and bark fuels. A major network of wood pellet distributors was mapped. It was concluded from a survey to these retailers that the Swedish residential market was now firmly in place and that the price of wood pellets was competitive with prices of traditional national fuels. A majority of pellet users in Austria, Sweden and the United States were pleased with pellet heating. One way to improve pellet distribution systems would be to optimise inventory management. An internal model for optimising inventory management, Pell-Sim, was constructed. For Sweden, wood pellets in 1997 represented the second most traded biofuel assortment, with 4.35 PJ or 18% of the total biofuel imports. Contrary to trade with other biofuel assortments, wood pellet trade

  11. SNM holdup assessment of Los Alamos exhaust ducts

    International Nuclear Information System (INIS)

    Marshall, R.S.

    1994-02-01

    Fissile material holdup in glovebox and fume hood exhaust ducting has been quantified for all Los Alamos duct systems. Gamma-based, nondestructive measurements were used to quantify holdup. The measurements were performed during three measurement campaigns. The first campaign, Phase I, provided foot-by-foot, semiquantitative measurement data on all ducting. These data were used to identify ducting that required more accurate (quantitative) measurement. Of the 280 duct systems receiving Phase I measurements, 262 indicated less than 50 g of fissile holdup and 19 indicated fissile holdup of 50 or more grams. Seven duct systems were measured in a second campaign, called Series 1, Phase II. Holdup estimates on these ducts ranged from 421 g of 235 U in a duct servicing a shut-down uranium-machining facility to 39 g of 239 Pu in a duct servicing an active plutonium-processing facility. Measurements performed in the second campaign proved excessively laborious, so a third campaign was initiated that used more efficient instrumentation at some sacrifice in measurement quality. Holdup estimates for the 12 duct systems measured during this third campaign ranged from 70 g of 235 U in a duct servicing analytical laboratories to 1 g of 235 U and 1 g of 239 Pu in a duct carrying exhaust air to a remote filter building. These quantitative holdup estimates support the conclusion made at the completion of the Phase I measurements that only ducts servicing shut-down uranium operations contain about 400 g of fissile holdup. No ventilation ducts at Los Alamos contain sufficient fissile material holdup to present a criticality safety concern

  12. Mechanisms of ion transport in the mesonephric collecting duct system of Bufo bufo as revealed by microelectrode recordings in isolated perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2002-01-01

    amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad......amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad...

  13. Mechanisms of ion transport in the mesonephric collecting duct system of Bufo bufo as revealed by microelectrode recordings in isolated perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2002-01-01

    amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad......amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad...

  14. Computational Aerodynamic Simulations of an 840 ft/sec Tip Speed Advanced Ducted Propulsor Fan System Model for Acoustic Methods Assessment and Development

    Science.gov (United States)

    Tweedt, Daniel L.

    2014-01-01

    Computational Aerodynamic simulations of an 840 ft/sec tip speed, Advanced Ducted Propulsor fan system were performed at five different operating points on the fan operating line, in order to provide detailed internal flow field information for use with fan acoustic prediction methods presently being developed, assessed and validated. The fan system is a sub-scale, lownoise research fan/nacelle model that has undergone extensive experimental testing in the 9- by 15- foot Low Speed Wind Tunnel at the NASA Glenn Research Center, resulting in quality, detailed aerodynamic and acoustic measurement data. Details of the fan geometry, the computational fluid dynamics methods, the computational grids, and various computational parameters relevant to the numerical simulations are discussed. Flow field results for three of the five operating conditions simulated are presented in order to provide a representative look at the computed solutions. Each of the five fan aerodynamic simulations involved the entire fan system, excluding a long core duct section downstream of the core inlet guide vane. As a result, only fan rotational speed and system bypass ratio, set by specifying static pressure downstream of the core inlet guide vane row, were adjusted in order to set the fan operating point, leading to operating points that lie on a fan operating line and making mass flow rate a fully dependent parameter. The resulting mass flow rates are in good agreement with measurement values. The computed blade row flow fields for all five fan operating points are, in general, aerodynamically healthy. Rotor blade and fan exit guide vane flow characteristics are good, including incidence and deviation angles, chordwise static pressure distributions, blade surface boundary layers, secondary flow structures, and blade wakes. Examination of the computed flow fields reveals no excessive boundary layer separations or related secondary-flow problems. A few spanwise comparisons between

  15. Leveraging Human-environment Systems in Residential Buildings for Aggregate Energy Efficiency and Sustainability

    Science.gov (United States)

    Xu, Xiaoqi

    Reducing the energy consumed in the built environment is a key objective in many sustainability initiatives. Existing energy saving methods have consisted of physical interventions to buildings and/or behavioral modifications of occupants. However, such methods may not only suffer from their own disadvantages, e.g. high cost and transient effect, but also lose aggregate energy saving potential due to the oftentimes-associated single-building-focused view and an isolated examination of occupant behaviors. This dissertation attempts to overcome the limitations of traditional energy saving research and practical approaches, and enhance residential building energy efficiency and sustainability by proposing innovative energy strategies from a holistic perspective of the aggregate human-environment systems. This holistic perspective features: (1) viewing buildings as mutual influences in the built environment, (2) leveraging both the individual and contextualized social aspects of occupant behaviors, and (3) incorporating interactions between the built environment and human behaviors. First, I integrate three interlinked components: buildings, residents, and the surrounding neighborhood, and quantify the potential energy savings to be gained from renovating buildings at the inter-building level and leveraging neighborhood-contextualized occupant social networks. Following the confirmation of both the inter-building effect among buildings and occupants' interpersonal influence on energy conservation, I extend the research further by examining the synergy that may exist at the intersection between these "engineered" building networks and "social" peer networks, focusing specifically on the additional energy saving potential that could result from interactions between the two components. Finally, I seek to reach an alignment of the human and building environment subsystems by matching the thermostat preferences of each household with the thermal conditions within their

  16. Experimental Analysis of Cool Traditional Solar Shading Systems for Residential Buildings

    Directory of Open Access Journals (Sweden)

    Anna Laura Pisello

    2015-03-01

    Full Text Available In recent years there has been a growing interest in the development and thermal-energy analysis of passive solutions for reducing building cooling needs and thus improving indoor thermal comfort conditions. In this view, several studies were carried out about cool roofs and cool coatings, producing acknowledged mitigation effects on urban heat island phenomenon. The purpose of this work is to investigate the thermal-energy performance of cool louvers of shutters, usually installed in residential buildings, compared to dark color traditional shading systems. To this aim, two full-scale prototype buildings were continuously monitored under summer conditions and the role of the cool shutter in reducing the overheating of the shading system and the energy requirements for cooling was analyzed. After an in-lab optical analysis of the cool coating, showing a huge solar reflectance increase with respect to the traditional configuration, i.e., by about 75%, field monitoring results showed that the cool shutter is able to decrease the indoor air temperature up to 2 °C under free floating conditions. The corresponding energy saving was about 25%, with even much higher peaks during very hot summer conditions.

  17. Residential Solar-Based Seasonal Thermal Storage Systems in Cold Climates: Building Envelope and Thermal Storage

    Directory of Open Access Journals (Sweden)

    Alexandre Hugo

    2012-10-01

    Full Text Available The reduction of electricity use for heating and domestic hot water in cold climates can be achieved by: (1 reducing the heating loads through the improvement of the thermal performance of house envelopes, and (2 using solar energy through a residential solar-based thermal storage system. First, this paper presents the life cycle energy and cost analysis of a typical one-storey detached house, located in Montreal, Canada. Simulation of annual energy use is performed using the TRNSYS software. Second, several design alternatives with improved thermal resistance for walls, ceiling and windows, increased overall air tightness, and increased window-to-wall ratio of South facing windows are evaluated with respect to the life cycle energy use, life cycle emissions and life cycle cost. The solution that minimizes the energy demand is chosen as a reference house for the study of long-term thermal storage. Third, the computer simulation of a solar heating system with solar thermal collectors and long-term thermal storage capacity is presented. Finally, the life cycle cost and life cycle energy use of the solar combisystem are estimated for flat-plate solar collectors and evacuated tube solar collectors, respectively, for the economic and climatic conditions of this study.

  18. Applying geographic information systems to delineate residential suburbs and summarise data based on individual parcel attributes

    Directory of Open Access Journals (Sweden)

    Stefan A. Sinske

    2013-02-01

    Full Text Available Background: Information aggregation to suburb level is of interest to engineers and urban planners. Readily available suburb boundaries do not always correspond to the suburb names recorded for individual properties in different data bases and unwanted errors are inherent. This mismatch of suburb names at different spatial scales poses a particular problem to analysts. As part of a parallel research project into the development of a robust guideline for suburb-based water demand analyses it was necessary to evaluate a large number of suburbs in terms of various attributes, one of which was the total suburb area.Objectives: Suburb boundaries were needed to assess the total suburb area. The objective of this research was to develop a novel geographic information system (GIS application to delineate suburbs with boundaries corresponding to information contained in another data base comprising individual property records. The suburb boundaries derived in this manner may not relate to municipal boundaries, or sociopolitical boundaries, nor do they have to. The fundamentally correct suburb boundary would be the one encompassing what is perceived to be the suburb based on the suburb name in a particular data base that also contains other interesting attributes, such as water use, of individual properties.Method: The ArcGIS environment was used to delineate suburbs by means of triangulated irregular network (TIN modelling. Boundaries for suburbs with predominantly residential land use were created that included all residential properties according to the suburb name field as recorded in the treasury system. Other vacant areas were also included so as to obtain the total suburb area. The methodology was developed to assist research in the field of potable water services, but the method presented could be applied to other services that require management of information at suburb level.Results: This article illustrates how a tedious task of suburb

  19. Applying geographic information systems to delineate residential suburbs and summarise data based on individual parcel attributes

    Directory of Open Access Journals (Sweden)

    Stefan A. Sinske

    2013-02-01

    Full Text Available Background: Information aggregation to suburb level is of interest to engineers and urban planners. Readily available suburb boundaries do not always correspond to the suburb names recorded for individual properties in different data bases and unwanted errors are inherent. This mismatch of suburb names at different spatial scales poses a particular problem to analysts. As part of a parallel research project into the development of a robust guideline for suburb-based water demand analyses it was necessary to evaluate a large number of suburbs in terms of various attributes, one of which was the total suburb area. Objectives: Suburb boundaries were needed to assess the total suburb area. The objective of this research was to develop a novel geographic information system (GIS application to delineate suburbs with boundaries corresponding to information contained in another data base comprising individual property records. The suburb boundaries derived in this manner may not relate to municipal boundaries, or sociopolitical boundaries, nor do they have to. The fundamentally correct suburb boundary would be the one encompassing what is perceived to be the suburb based on the suburb name in a particular data base that also contains other interesting attributes, such as water use, of individual properties. Method: The ArcGIS environment was used to delineate suburbs by means of triangulated irregular network (TIN modelling. Boundaries for suburbs with predominantly residential land use were created that included all residential properties according to the suburb name field as recorded in the treasury system. Other vacant areas were also included so as to obtain the total suburb area. The methodology was developed to assist research in the field of potable water services, but the method presented could be applied to other services that require management of information at suburb level. Results: This article illustrates how a tedious task of suburb

  20. Modeling and parametric study of a 1 kWe HT-PEMFC-based residential micro-CHP system

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2011-01-01

    A detailed thermodynamic, kinetic and geometric model of a micro-CHP (Combined-Heatand-Power) residential system based on High Temperature-Proton Exchange Membrane Fuel Cell (HT-PEMFC) technology is developed, implemented and validated. HT-PEMFC technology is investigated as a possible candidate...... for fuel cell-based residential micro-CHP systems, since it can operate at higher temperature than Nafion-based fuel cells, and therefore can reach higher cogeneration efficiencies. The proposed system can provide electric power, hot water, and space heating for a typical Danish single-family household....... A complete fuel processing subsystem, with all necessary balance-of-plant components, is modeled and coupled to the fuel cell stack subsystem. The micro-CHP system’s synthesis/ design and operational pattern is analyzed by means of a parametric study. The parametric study is conducted to determine the most...

  1. Multiobjective optimisation of energy systems and building envelope retrofit in a residential community

    International Nuclear Information System (INIS)

    Wu, Raphael; Mavromatidis, Georgios; Orehounig, Kristina; Carmeliet, Jan

    2017-01-01

    Highlights: • Simultaneous optimisation of building envelope retrofit and energy systems. • Retrofit and energy systems change interact and should be considered simultaneously. • Case study quantifies cost-GHG emission tradeoffs for different retrofit options. - Abstract: In this paper, a method for a multi-objective and simultaneous optimisation of building energy systems and retrofit is presented. Tailored to be suitable for the diverse range of existing buildings in terms of age, size, and use, it combines dynamic energy demand simulation to explore individual retrofit scenarios with an energy hub optimisation. Implemented as an epsilon-constrained mixed integer linear program (MILP), the optimisation matches envelope retrofit with renewable and high efficiency energy supply technologies such as biomass boilers, heat pumps, photovoltaic and solar thermal panels to minimise life cycle cost and greenhouse gas (GHG) emissions. Due to its multi-objective, integrated assessment of building transformation options and its ability to capture both individual building characteristics and trends within a neighbourhood, this method is aimed to provide developers, neighbourhood and town policy makers with the necessary information to make adequate decisions. Our method is deployed in a case study of typical residential buildings in the Swiss village of Zernez, simulating energy demands in EnergyPlus and solving the optimisation problem with CPLEX. Although common trade-offs in energy system and retrofit choice can be observed, optimisation results suggest that the diversity in building age and size leads to optimal strategies for retrofitting and building system solutions, which are specific to different categories. With this method, GHG emissions of the entire community can be reduced by up to 76% at a cost increase of 3% compared to the current emission levels, if an optimised solution is selected for each building category.

  2. Mammary Duct Ectasia

    Science.gov (United States)

    ... lumps Mammary duct ectasia Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  3. Ducted fuel injection

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Charles J.

    2018-03-06

    Various technologies presented herein relate to enhancing mixing inside a combustion chamber to form one or more locally premixed mixtures comprising fuel and charge-gas with low peak fuel to charge-gas ratios to enable minimal, or no, generation of soot and other undesired emissions during ignition and subsequent combustion of the locally premixed mixtures. To enable sufficient mixing of the fuel and charge-gas, a jet of fuel can be directed to pass through a bore of a duct causing charge-gas to be drawn into the bore creating turbulence to mix the fuel and the drawn charge-gas. The duct can be located proximate to an opening in a tip of a fuel injector. The duct can comprise of one or more holes along its length to enable charge-gas to be drawn into the bore, and further, the duct can cool the fuel and/or charge-gas prior to combustion.

  4. Modified nasolacrimal duct stenting

    International Nuclear Information System (INIS)

    Tian Min; Jin Mei; Chen Huanjun; Li Yi

    2008-01-01

    Objective: Traditional nasolacrimal duct stenting possesses some shortcoming including difficulty of pulling ball head guide wire from the nasal cavity with turbinate hypertrophy and nasal septal deviation. The new method of nose-oral tube track establishment can overcome the forementioned and increase the successful rate. Methods: 5 F catheter and arterial sheath were modified to be nasolacrimal duct stent delivery device respectively. Antegrade dacryocystography was taken firstly to display the obstructed site and followed by the modified protocol of inserting the guide wire through nasolacrimal duct and nasal cavity, and establishing the stent delivery track for retrograde stent placement. Results: 5 epiphora patients with failure implantation by traditional method were all succeeded through the modified stenting (100%). During 6-mouth follow-up, no serious complications and reocclusion occurred. Conclusion: The establishment of eye-nose-mouth-nose of external nasal guide wire track can improve the successful rate of nasolacrimal duct stenting. (authors)

  5. Optimization of air ducts for nuclear reactor power generation station

    International Nuclear Information System (INIS)

    Hirao, Katsumi; Yoshino, Hirokazu; Sonoda, Takayuki

    1991-01-01

    In the optimization study on the heating, ventilating and air conditions system in Nuclear Reactor Power Generation Station, proper arrangement of air ducts has been studied using the experimental and analytical investigation from a viewpoint of duct arrangement optimization. This study consists of two parts. Part I is optimization of air ducts in the corridors and Part II is optimization of air duct in each room. In part I, from viewpoints of confinement of radioactive materials in facilities having possible radioactive contamination and improvement of thermal environment for workers, the authors have studied air ducts system in which fresh air is supplied to corridors and heat removal and ventilation for each room are performed by transferring air from the corridors, instead of current ducts system with supply duct to each room. In part II, the condenser room with complex configuration and large space, and the electrical equipment room with simple space are selected for model areas. Based on these studies, experimental and analytical investigation (using a three-dimensional thermal hydraulic analysis) technique has been established, and the effective design method for duct arrangement of HVAC design has been verified for Boiling Water Reactor Power Station. The air-duct arrangements optimized in this study are applied to an Advanced Boiling Water Reactor Power Station in trial and reduction of the air-duct quantity is confirmed

  6. The excretory system of the liver in wild animals. VI. Biliary ducts of the great anteater (Myrmecophaga tridactyla

    Directory of Open Access Journals (Sweden)

    Maria Angélica Miglino

    1992-12-01

    Full Text Available The systematization of the biliary ducts of the liver of the great anteater (Myrmecophaga tridactyla is analyzed. The ductus choledocus has no affluents and results from the union of the ductus cysticus and the ductus hepaticus always arises from theramus principalis dexter and the ramus principalis sinister, and is seen without tributaries in three cases, receiving them meanwhile in the other one. The ramus principalis dexter is made up of the ramus lateralis lobi dextri and the ramus medialis lobi dextri. The ramus principalis sinister is formed by the ramus lateralis lobi sinistri, the ramus lobi sinistri and the ramus lobi quadrati.

  7. Expression of aquaporin 9 in rat liver and efferent ducts of the male reproductive system after neonatal diethylstilbestrol exposure

    DEFF Research Database (Denmark)

    Wellejus, Anja; Jensen, Henrik E; Loft, Steffen

    2008-01-01

    Aquaporins (AQP) have important solute transport functions in many tissues including the epididymal efferent ducts (ED) and in the liver. We investigated the effect of neonatal exposure to diethylstilbestrol (DES) on AQP9 expressions in the ED and in the liver of rats. DES was administered from day...... to the epithelial cells of the ED. In conclusion, neonatal DES exposure appears to upregulate AQP9 channels in the ED in male rats, whereas a downregulation in the hepatic expression was observed, particularly in the periacinous area....

  8. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, Dave [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-07

    "9A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely on encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences; 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs; 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.

  9. Curved-Duct

    Directory of Open Access Journals (Sweden)

    Je Hyun Baekt

    2000-01-01

    Full Text Available A numerical study is conducted on the fully-developed laminar flow of an incompressible viscous fluid in a square duct rotating about a perpendicular axis to the axial direction of the duct. At the straight duct, the rotation produces vortices due to the Coriolis force. Generally two vortex cells are formed and the axial velocity distribution is distorted by the effect of this Coriolis force. When a convective force is weak, two counter-rotating vortices are shown with a quasi-parabolic axial velocity profile for weak rotation rates. As the rotation rate increases, the axial velocity on the vertical centreline of the duct begins to flatten and the location of vorticity center is moved near to wall by the effect of the Coriolis force. When the convective inertia force is strong, a double-vortex secondary flow appears in the transverse planes of the duct for weak rotation rates but as the speed of rotation increases the secondary flow is shown to split into an asymmetric configuration of four counter-rotating vortices. If the rotation rates are increased further, the secondary flow restabilizes to a slightly asymmetric double-vortex configuration. Also, a numerical study is conducted on the laminar flow of an incompressible viscous fluid in a 90°-bend square duct that rotates about axis parallel to the axial direction of the inlet. At a 90°-bend square duct, the feature of flow by the effect of a Coriolis force and a centrifugal force, namely a secondary flow by the centrifugal force in the curved region and the Coriolis force in the downstream region, is shown since the centrifugal force in curved region and the Coriolis force in downstream region are dominant respectively.

  10. Technical and economical assessment of the utilization of photovoltaic systems in residential buildings: The case of Jordan

    International Nuclear Information System (INIS)

    Al-Salaymeh, A.; Al-Hamamre, Z.; Sharaf, F.; Abdelkader, M.R.

    2010-01-01

    This paper studies the feasibility of utilizing photovoltaic systems in a standard residential apartment in Amman city in Jordan. Data on solar radiation, sunshine duration and the ambient temperature has been recorded in Amman city. An apartment in Amman was chosen as a case study to conduct energy and economic calculations. The electrical power needs and cost were calculated for the apartment. The component design and cost of PV system required to supply required energy was calculated and the payback period for the suggested stand-alone PV system in this paper was estimated in a constant inflation rate in electricity price similar to that of interest rate. The calculated payback period was high in a stand-alone system, to decrease payback period a grid-connected PV system is suggested. Considering an annual increase of 3% in electricity price, 15% of payback period was decreased in a stand-alone PV system and 21% in a grid-connected PV system. The output results of this study show that installation of PV system in a residential flat in Jordan may not be economically rewarding owing to the high cost of PV system compared to the cost of grid electricity. A feed-in tariff law of solar electricity may help to reduce PV system cost like the case of Germany. Additional conclusions are PV systems may be economically rewarding in Jordan if applied in locations far from electrical grid or in remote large scale PV power installations to overcome economical limitations of PV technology.

  11. Measure Guideline: Summary of Interior Ducts in New Construction, Including an Efficient, Affordable Method to Install Fur-Down Interior Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Beal, D. [BA-PIRC, Cocoa, FL (United States); McIlvaine, J. [BA-PIRC, Cocoa, FL (United States); Fonorow, K. [BA-PIRC, Cocoa, FL (United States); Martin, E. [BA-PIRC, Cocoa, FL (United States)

    2011-11-01

    This document illustrates guidelines for the efficient installation of interior duct systems in new housing, including the fur-up chase method, the fur-down chase method, and interior ducts positioned in sealed attics or sealed crawl spaces.

  12. Systems Modelling of the Socio-Technical Aspects of Residential Electricity Use and Network Peak Demand

    Science.gov (United States)

    Lewis, Jim; Mengersen, Kerrie; Buys, Laurie; Vine, Desley; Bell, John; Morris, Peter; Ledwich, Gerard

    2015-01-01

    Provision of network infrastructure to meet rising network peak demand is increasing the cost of electricity. Addressing this demand is a major imperative for Australian electricity agencies. The network peak demand model reported in this paper provides a quantified decision support tool and a means of understanding the key influences and impacts on network peak demand. An investigation of the system factors impacting residential consumers’ peak demand for electricity was undertaken in Queensland, Australia. Technical factors, such as the customers’ location, housing construction and appliances, were combined with social factors, such as household demographics, culture, trust and knowledge, and Change Management Options (CMOs) such as tariffs, price, managed supply, etc., in a conceptual ‘map’ of the system. A Bayesian network was used to quantify the model and provide insights into the major influential factors and their interactions. The model was also used to examine the reduction in network peak demand with different market-based and government interventions in various customer locations of interest and investigate the relative importance of instituting programs that build trust and knowledge through well designed customer-industry engagement activities. The Bayesian network was implemented via a spreadsheet with a tickbox interface. The model combined available data from industry-specific and public sources with relevant expert opinion. The results revealed that the most effective intervention strategies involve combining particular CMOs with associated education and engagement activities. The model demonstrated the importance of designing interventions that take into account the interactions of the various elements of the socio-technical system. The options that provided the greatest impact on peak demand were Off-Peak Tariffs and Managed Supply and increases in the price of electricity. The impact in peak demand reduction differed for each of the

  13. Systems Modelling of the Socio-Technical Aspects of Residential Electricity Use and Network Peak Demand.

    Science.gov (United States)

    Lewis, Jim; Mengersen, Kerrie; Buys, Laurie; Vine, Desley; Bell, John; Morris, Peter; Ledwich, Gerard

    2015-01-01

    Provision of network infrastructure to meet rising network peak demand is increasing the cost of electricity. Addressing this demand is a major imperative for Australian electricity agencies. The network peak demand model reported in this paper provides a quantified decision support tool and a means of understanding the key influences and impacts on network peak demand. An investigation of the system factors impacting residential consumers' peak demand for electricity was undertaken in Queensland, Australia. Technical factors, such as the customers' location, housing construction and appliances, were combined with social factors, such as household demographics, culture, trust and knowledge, and Change Management Options (CMOs) such as tariffs, price, managed supply, etc., in a conceptual 'map' of the system. A Bayesian network was used to quantify the model and provide insights into the major influential factors and their interactions. The model was also used to examine the reduction in network peak demand with different market-based and government interventions in various customer locations of interest and investigate the relative importance of instituting programs that build trust and knowledge through well designed customer-industry engagement activities. The Bayesian network was implemented via a spreadsheet with a tickbox interface. The model combined available data from industry-specific and public sources with relevant expert opinion. The results revealed that the most effective intervention strategies involve combining particular CMOs with associated education and engagement activities. The model demonstrated the importance of designing interventions that take into account the interactions of the various elements of the socio-technical system. The options that provided the greatest impact on peak demand were Off-Peak Tariffs and Managed Supply and increases in the price of electricity. The impact in peak demand reduction differed for each of the locations

  14. Autoignition in a premixing-prevaporizing fuel duct using 3 different fuel injection systems at inlet air temperatures to 1250 K

    Science.gov (United States)

    Tacina, R. R.

    1983-01-01

    Conditions were determined in a continuous-flow, premixing-prevaporizing duct at which autoignition occurred. Test conditions were representative of an advanced, regenerative-cycle, automotive gas turbine. The test conditions inlet air temperatures from 600 to 1250 K (a vitiated preheater was used), pressures from 170 to 600 kPa, air velocities of 10 to 30 m/sec, equivalence ratios from 0.3 to 1.0, mixing lengths from 10 to 60 cm, and residence times of 2 to 100 ms. The fuel was diesel number 2. The duct was insulated and had an inside diameter of 12 cm. Three different fuel injection systems were used: One was a single simplex pressure atomizer, and the other two were multiple-source injectors. The data obtained with the simplex and one of the multiple-source injectors agreed satisfactorily with the references and correlated with an Arrenhius expression. The data obtained with the other multiple source injector, which used multiple cones to improve the fuel-air distribution, did not correlate well with residence time.

  15. Active noise control in a duct to cancel broadband noise

    Science.gov (United States)

    Chen, Kuan-Chun; Chang, Cheng-Yuan; Kuo, Sen M.

    2017-09-01

    The paper presents cancelling duct noises by using the active noise control (ANC) techniques. We use the single channel feed forward algorithm with feedback neutralization to realize ANC. Several kinds of ducts noises including tonal noises, sweep tonal signals, and white noise had investigated. Experimental results show that the proposed ANC system can cancel these noises in a PVC duct very well. The noise reduction of white noise can be up to 20 dB.

  16. Grid-connected photovoltaic systems for Malaysian residential sector: Effects of component costs, feed-in tariffs, and carbon taxes

    International Nuclear Information System (INIS)

    Lau, K.Y.; Muhamad, N.A.; Arief, Y.Z.; Tan, C.W.; Yatim, A.H.M.

    2016-01-01

    Blessed with abundant solar radiation, Malaysia has a huge potential for grid-connected PV (photovoltaic) installations, particularly for its fast-growing residential sector. Nevertheless, Malaysia's PV installation capacity is relatively small compared with the global PV capacity. Significantly, the pricing mechanisms for grid-connected PV projects need to be appropriately assessed to build up the public's confidence to invest in PV projects. In this paper, we analyze the effects of component costs, FiTs (feed-in tariffs), and carbon taxes on grid-connected PV systems in Malaysian residential sector using the HOMER (Hybrid Optimization of Multiple Energy Resources) software. Results demonstrate that the implementation of grid-connected PV systems is highly feasible with PV array costs of $ 1120/kW or lower. For higher PV array costs up to $ 2320/kW, introducing an FiT rate three times higher ($ 0.30/kWh) than the grid tariff for a 100 kW grid sale capacity will, NPC-wise, prioritize grid-connected PV systems over the utility grid. By implementing the FiT ($ 0.50/kWh) and the carbon tax ($ 36/metric ton) schemes simultaneously, grid-connected PV systems will remain as the optimal systems even for costly PV arrays (up to $ 4000/kW). The findings are of paramount importance as far as PV pricing variability is concerned. - Highlights: • Grid-connected PV for Malaysian residential sector has been analyzed using HOMER. • Component costs, feed-in tariffs, and carbon taxes affect optimal system types. • Grid-connected PV projects are feasible for low PV array costs ($ 1120/kW or lower). • For higher PV array and inverter costs, feed-in tariffs should be implemented. • Combining feed-in tariffs with carbon taxes are effective for further lowering NPCs.

  17. Comparison of adsorption systems using natural gas fired fuel cell as heat source, for residential air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Clausse, M.; Meunier, F. [LGP2ES, Cnam-IFFI (EA21), case 331, 292 rue Saint-Martin, 75141 Paris Cedex 03 (France); Coulie, J.; Herail, E. [N-GHY, Site Industriel Saint Antoine, ZI Montplaisir, 51 rue Isaac Newton, 81000 Albi (France)

    2009-06-15

    This article aims to evaluate the performances of an adsorption system driven thanks to the heat rejected by the post-combustion exhaust gases of a reformer/fuel cell system for residential air-conditioning application. Three adsorption pairs were compared: activated carbon/methanol, silica gel/water and zeolite/water. Taking into account both cooling power and sensitivity to performances of the heat rejection and recovery exchangers, it appears that zeolite 13X/water is the adsorption pair giving the best performance for this application. Nevertheless, a more detailed model would be of interest to better quantify the heat transfer impact on performance. (author)

  18. System-Cost-Optimized Smart EVSE for Residential Application: Final Technical Report including Manufacturing Plan

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Charles [Delta Products, Triangle Park, NC (United States)

    2015-05-15

    In the 2nd quarter of 2012, a program was formally initiated at Delta Products to develop smart-grid-enabled Electric Vehicle Supply Equipment (EVSE) product for residential use. The project was funded in part by the U.S. Department of Energy (DOE), under award DE-OE0000590. Delta products was the prime contractor to DOE during the three year duration of the project. In addition to Delta Products, several additional supplier-partners were engaged in this research and development (R&D) program, including Detroit Edison DTE, Mercedes Benz Research and Development North America, and kVA. This report summarizes the program and describes the key research outcomes of the program. A technical history of the project activities is provided, which describes the key steps taken in the research and the findings made at successive stages in the multi-stage work. The evolution of an EVSE prototype system is described in detail, culminating in prototypes shipped to Department of Energy Laboratories for final qualification. After the program history is reviewed, the key attributes of the resulting EVSE are described in terms of functionality, performance, and cost. The results clearly demonstrate the ability of this EVSE to meet or exceed DOE's targets for this program, including: construction of a working product-intent prototype of a smart-grid-enabled EVSE, with suitable connectivity to grid management and home-energy management systems, revenue-grade metering, and related technical functions; and cost reduction of 50% or more compared to typical market priced EVSEs at the time of DOE's funding opportunity announcement (FOA), which was released in mid 2011. In addition to meeting all the program goals, the program was completed within the original budget and timeline established at the time of the award. The summary program budget and timeline, comparing plan versus actual values, is provided for reference, along with several supporting explanatory notes. Technical

  19. Potential Effect and Analysis of High Residential Solar Photovoltaic (PV Systems Penetration to an Electric Distribution Utility (DU

    Directory of Open Access Journals (Sweden)

    Jeffrey Tamba Dellosa

    2016-11-01

    Full Text Available The Renewable Energy Act of 2008 in the Philippines provided an impetus for residential owners to explore solar PV installations at their own rooftops through the Net-Metering policy. The Net-Metering implementation through the law however presented some concerns with inexperienced electric DU on the potential effect of high residential solar PV system installations. It was not known how a high degree of solar integration to the grid can possibly affect the operations of the electric DU in terms of energy load management. The primary objective of this study was to help the local electric DU in the analysis of the potential effect of high residential solar PV system penetration to the supply and demand load profile in an electric distribution utility (DU grid in the province of Agusan del Norte, Philippines. The energy consumption profiles in the year 2015 were obtained from the electric DU operating in the area. An average daily energy demand load profile was obtained from 0-hr to the 24th hour of the day based from the figures provided by the electric DU. The assessment part of the potential effect of high solar PV system integration assumed four potential total capacities from 10 Mega Watts (MW to 40 MW generated by all subscribers in the area under study at a 10 MW interval. The effect of these capacities were measured and analyzed with respect to the average daily load profile of the DU. Results of this study showed that a combined installations beyond 20 MWp coming from all subscribers is not viable for the local electric DU based on their current energy demand or load profile. Based from the results obtained, the electric DU can make better decisions in the management of high capacity penetration of solar PV systems in the future, including investment in storage systems when extra capacities are generated. Article History: Received July 15th 2016; Received in revised form Sept 23rd 2016; Accepted Oct 1st 2016; Available online How to Cite

  20. Performance Assessment of a Hybrid Solar-Geothermal Air Conditioning System for Residential Application: Energy, Exergy, and Sustainability Analysis

    Directory of Open Access Journals (Sweden)

    Yasser Abbasi

    2016-01-01

    Full Text Available This paper investigates the performance of a ground source heat pump that is coupled with a photovoltaic system to provide cooling and heating demands of a zero-energy residential building. Exergy and sustainability analyses have been conducted to evaluate the exergy destruction rate and SI of different compartments of the hybrid system. The effects of monthly thermal load variations on the performance of the hybrid system are investigated. The hybrid system consists of a vertical ground source heat exchanger, rooftop photovoltaic panels, and a heat pump cycle. Exergetic efficiency of the solar-geothermal heat pump system does not exceed 10 percent, and most exergy destruction takes place in photovoltaic panel, condenser, and evaporator. Although SI of PV system remains constant during a year, SI of GSHP varies depending on cooling and heating mode. The results also show that utilization of this hybrid system can reduce CO2 emissions by almost 70 tons per year.

  1. Bile Duct Exploration

    Science.gov (United States)

    ... 223.2273 Request an Appointment Contact Us Share Facebook Twitter Linkedin Email Bile Duct Exploration Menu Print Full Article Overview Test Details Results and Follow-Up Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We ...

  2. Duct Leakage Repeatability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-01

    The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques for duct leakage using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards. The three duct leak measurement methods assessed in this report are the two duct pressurization methods that are commonly used by many practitioners and the DeltaQ technique. These are methods B, C and A, respectively of the ASTM E1554 standard. Although it would be useful to evaluate other duct leak test methods, this study focused on those test methods that are commonly used and are required in various test standards, such as BPI (2010), RESNET (2014), ASHRAE 62.2 (2013), California Title 24 (CEC 2012), DOE Weatherization and many other energy efficiency programs.

  3. System simulation of compressed hydrogen storage based residential wind hybrid power systems

    Science.gov (United States)

    Raju, Mandhapati; Khaitan, Siddhartha Kumar

    2012-07-01

    This paper deals with the storage of excess wind energy, in a hybrid wind power system, in the form of compressed hydrogen. A system simulation model is developed in Matlab/Simulink platform for the charging and discharging dynamics of compressed hydrogen storage system integrated with the wind turbine and the fuel cell. Wind model is used to estimate the power generation in the wind turbine. When the wind power generation exceeds the load, the excess power is diverted to the electrolyzer to produce hydrogen. As and when the pressure inside the electrolyzer builds, a compressor is operated intermittently (for higher efficiency) to divert the hydrogen into high pressure cylinders. When demand exceeds the power generation, fuel cell supplies the power to the load. A number of fuel cell stacks are provided to meet the required load. The overall efficiency of the storage system, defined as the ratio of the useful energy derived from the storage system to the energy diverted to the storage system is found to be 24.5% for the compressed hydrogen storage based system.

  4. Solarize Guidebook: A Community Guide to Collective Purchasing of Residential PV Systems

    Energy Technology Data Exchange (ETDEWEB)

    Irvine, L.; Sawyer, A.; Grove, J.

    2011-02-01

    This handbook is intended as a road map for project planners and solar advocates who want to convert interest into action, to break through market barriers and permanently transform the market for residential solar installations in their communities. It describes the key elements of the Solarize campaigns in Portland, and offers several program refinements from projects beyond Portland. The handbook provides lessons, considerations, and step-by-step plans for project organizers to replicate the success of Solarize Portland.

  5. Enucleation or exenteration in two dogs with previous parotid duct transposition: parotid duct ligation versus reverse parotid duct transposition.

    Science.gov (United States)

    Young, Whitney M; Betbeze, Caroline M; Fisher, Stephen C; Boulay, James P

    2017-08-27

    Two dogs with previous parotid duct transpositions presented with unrelated ocular disease. In both cases, ophthalmic examination revealed the need for enucleation or exenteration. In case 1, systemic coccidioidomycosis was diagnosed with panuveitis and secondary glaucoma of the left eye. In this case, the parotid duct was ligated at the time of enucleation to stop salivary secretions. This dog encountered morbidity in the form of a sialocele that did not resolve for 11 months. In case 2, ultrasound and computed tomography revealed a discrete mass within the left medial orbit that was suspected to arise from the nictitating membrane. A combination of exenteration and parotid duct transposition reversal was performed to avoid morbidity associated with ligation of the parotid duct. The dog encountered no complications from this novel procedure. This case report represents the first report of re-routing a transposed parotid duct from the ventral conjunctival sac back to the mouth at the time of enucleation or exenteration in the dog. © 2017 American College of Veterinary Ophthalmologists.

  6. Implementation and Control of a Residential Electrothermal Microgrid Based on Renewable Energies, a Hybrid Storage System and Demand Side Management

    Directory of Open Access Journals (Sweden)

    Julio Pascual

    2014-01-01

    Full Text Available This paper proposes an energy management strategy for a residential electrothermal microgrid, based on renewable energy sources. While grid connected, it makes use of a hybrid electrothermal storage system, formed by a battery and a hot water tank along with an electrical water heater as a controllable load, which make possible the energy management within the microgrid. The microgrid emulates the operation of a single family home with domestic hot water (DHW consumption, a heating, ventilation and air conditioning (HVAC system as well as the typical electric loads. An energy management strategy has been designed which optimizes the power exchanged with the grid profile in terms of peaks and fluctuations, in applications with high penetration levels of renewables. The proposed energy management strategy has been evaluated and validated experimentally in a full scale residential microgrid built in our Renewable Energy Laboratory, by means of continuous operation under real conditions. The results show that the combination of electric and thermal storage systems with controllable loads is a promising technology that could maximize the penetration level of renewable energies in the electric system.

  7. Post-evaluation of a ground source heat pump system for residential space heating in Shanghai China

    Science.gov (United States)

    Lei, Y.; Tan, H. W.; Wang, L. Z.

    2017-11-01

    Residents of Southern China are increasingly concerned about the space heating in winter. The chief aim of the present work is to find a cost-effective way for residential space heating in Shanghai, one of the biggest city in south China. Economic and energy efficiency of three residential space heating ways, including ground source heat pump (GSHP), air source heat pump (ASHP) and wall-hung gas boiler (WHGB), are assessed based on Long-term measured data. The results show that the heat consumption of the building is 120 kWh/m2/y during the heating season, and the seasonal energy efficiency ratio (SEER) of the GSHP, ASHP and WHGB systems are 3.27, 2.30, 0.88 respectively. Compared to ASHP and WHGB, energy savings of GSHP during the heating season are 6.2 kgce/(m2.y) and 2.2 kgce/(m2.y), and the payback period of GSHP are 13.3 and 7.6 years respectively. The sensitivity analysis of various factors that affect the payback period is carried out, and the results suggest that SEER is the most critical factor affecting the feasibility of ground source heat pump application, followed by building load factor and energy price factor. These findings of the research have led the author to the conclusion that ground source heat pump for residential space heating in Shanghai is a good alternative, which can achieve significant energy saving benefits, and a good system design and operation management are key factors that can shorten the payback period.

  8. Seismic assessment of the Pickering pressure relief duct

    International Nuclear Information System (INIS)

    Ghobarah, A.

    1995-05-01

    The objectives of the study are to examine the structural response of the Pickering pressure relief duct when subjected to earthquake ground motion and to estimate the seismic withstand capacity of various components of the structural system on the basis of performance criteria consistent with the safety function of the duct. (author). 24 refs., 16 tabs., 31 figs

  9. Financing, Overhead, and Profit: An In-Depth Discussion of Costs Associated with Third-Party Financing of Residential and Commercial Photovoltaic Systems

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, D.; Friedman, B.; Margolis, R.

    2013-10-01

    Previous work quantifying the non-hardware balance-of-system costs -- or soft costs -- associated with building a residential or commercial photovoltaic (PV) system has left a significant portion unsegmented in an 'other soft costs' category. This report attempts to better quantify the 'other soft costs' by focusing on the financing, overhead, and profit of residential and commercial PV installations for a specific business model. This report presents results from a bottom-up data-collection and analysis of the upfront costs associated with developing, constructing, and arranging third-party-financed residential and commercial PV systems. It quantifies the indirect corporate costs required to install distributed PV systems as well as the transactional costs associated with arranging third-party financing.

  10. Solarize Guidebook: A Community Guide to Collective Purchasing of Residential PV Systems (Book)

    Energy Technology Data Exchange (ETDEWEB)

    2012-05-01

    This guidebook is intended as a road map for project planners and solar advocates who want to convert 'interest' into 'action,' to break through market barriers and permanently transform the market for residential solar installations in their communities. It describes the key elements of the Solarize campaigns in Portland, and offers several program refinements from projects beyond Portland. The guidebook provides lessons, considerations, and step-by-step plans for project organizers to replicate the success of Solarize Portland.

  11. Application of an almost ideal demand system (AIDS) to Ethiopian rural residential energy use: Panel data evidence

    International Nuclear Information System (INIS)

    Guta, Dawit Diriba

    2012-01-01

    It is well known that poor rural households in low-income economies are reliant on traditional fuels to meet basic domestic energy needs, but little is known about the specific underlying socio-economic drivers of residential fuel choices in Ethiopia. I used the linear approximation almost ideal demand system (LAAIDS) with normalized prices to compute expenditure elasticity and a multinomial logit model (MLM) to examine household fuel use. The LAAIDS model result showed that expenditure was elastic for modern fuels, but inelastic for traditional fuels. Regression results from the MLM indicated that fuel choice behaviour of rural households could be more accurately described as ‘fuel stacking’ behaviour as opposed to the ‘energy ladder’ hypothesis. In rural areas household fuel choice may be constrained by limited access to commercial fuels and efficient cook stoves, supply dependency and affordability, consumer preferences and a web of other intricate factors. Rural households had less incentive for fuel switching due to underlying factors and the availability of fuel wood without direct financial cost. With continued deforestation and receding forests, households are expected to develop inter fuel substitution and switching behaviour conditional on access to modern energy technologies. - Highlights: ► Two step LAAIDS model and MLM were applied to analysis of residential fuel use. ► I examined issues of ‘energy ladder’ versus ‘fuel stacking’ behavior of households. ► Controlling other factors increase in welfare increases demand for modern fuel. ► Traditional fuels are income inelastic but not necessarily cheaper. ► Residential fuel choice is determined by intricate web of socio-economic factors.

  12. Control Method Based on Demand Response Needs of Isolated Bus Regulation with Series-Resonant Converters for Residential Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Shu-Huai Zhang

    2017-05-01

    Full Text Available Considering the effects of isolation and high efficiency, a series-resonant DC-DC converter (L-L-C type, with two inductors and a capacitor has been introduced into a residential photovoltaic (PV generation and storage system in this work, and a voltage gain curve upwarp drifting problem was found. In this paper, the reason of upwarp drifting in the voltage gain curve is given, and a new changing topological control method to solve the voltage regulation problem under light load conditions is proposed. Firstly, the ideal and actual first harmonic approximation (FHA models are given, and this drifting problem is ascribed to the multiple peaks of higher-order resonance between resonant tank and parasitic capacitors. Then the paper presents the pulse-frequency-modulation (PFM driver signals control method to translate the full-bridge LLC into a half-bridge LLC converter, and with this method the voltage gain could easily be reduced by half. Based on this method, the whole voltage and resonant current sharing control methods in on-line and off-line mode are proposed. The parameters design and optimization methods are also discussed in detail. Finally, a residential PV system platform based on the proposed parallel 7-kW full-bridge LLC converter is built to verify the proposed control method and theoretical analysis.

  13. Power and Energy Management with Battery Storage for a Hybrid Residential PV-Wind System – A Case Study for Denmark

    DEFF Research Database (Denmark)

    Stroe, Daniel-Ioan; Zaharof, Andreea; Iov, Florin

    2018-01-01

    The energy generation paradigm is shifting from centralized fossil-fuel-based generation to distributed-based renewable generation. Thus, hybrid residential energy systems based on wind turbines, PV panels and/or micro-turbines are gaining more and more terrain. Nevertheless, such a system needs...... to be coupled with an energy storage solution, most often a battery, in order to mitigate its power generation variability and to ensure a stable and reliable operation. In this work, two power and energy management strategies for a hybrid residential PV-wind system with battery energy storage were evaluated...

  14. Using ANNS to predict energy consumption of split AC systems in residential buildings and offices

    Energy Technology Data Exchange (ETDEWEB)

    Karatasou, S.; Santamouris, M.; Geros, V. [National and Kapodistrian Univ. of Athens., Athens (Greece). Dept. of Physics

    2007-07-01

    Artificial neural networks (ANNs) were used to predict AC power consumption in residential and small office buildings in Greece. The aim of the study was to produce a simple algorithm capable of predicting AC power consumption for a period of 24 hours. The performance of short-term predictors was evaluated. The predictive abilities of single step and 24-step predictors were then compared. Real data from an apartment building and a small office building in Athens were used. Datasets covered the summer period, and input variables were pre-selected among the available environmental and calendar variables. Feed forward ANNs with a single hidden layer of units were used. A single linear output to predict hourly energy consumptions consisted of 3 parts: the identification of all potential relevant inputs; the selection of hidden units for the preliminary set of inputs; and the removal of irrelevant inputs and useless hidden units through a subtractive phase. A Lavenberg Marquardt (LM) algorithm was used to train the networks. The network architecture was determined for both datasets through the selection procedures. Performance of the predictors was evaluated using the considered training and test sets. Results showed that both the single step and the 24-step predictors were accurate in the case of office buildings. However, the apartment building mean bias error (MBE) was approximately 10 per cent. Attempts to predict the residential building's energy consumption over a 24 hour period yielded an MBE of more than 30 per cent. 10 refs., 2 tabs., 3 figs.

  15. Magnetic resonance imaging of Muellerian duct anomalies in children

    International Nuclear Information System (INIS)

    Li, Yi; Phelps, Andrew; Zapala, Matthew A.; MacKenzie, John D.; MacKenzie, Tippi C.; Courtier, Jesse

    2016-01-01

    Muellerian duct anomalies encompass a wide variety of disorders resulting from abnormalities in the embryological development of the Muellerian ducts. In the prepubertal pediatric population, Muellerian duct anomalies are often incidental findings on studies obtained for other reasons. The onset of menses can prompt more clinical symptoms. Proper characterization of Muellerian duct anomalies is important because these anomalies can affect the development of gynecological disorders as well as fertility. Muellerian duct anomalies also carry a high association with other congenital anomalies, particularly renal abnormalities. MRI is widely considered the best modality for assessing Muellerian duct anomalies; it provides multiplanar capability, clear anatomical detail and tissue characterization without ionizing radiation. MRI allows for careful description of Muellerian duct anomalies, often leading to classification into the most widely accepted classification system for Muellerian duct anomalies. This system, developed by the American Society of Reproductive Medicine, includes seven subtypes: uterine agenesis/hypoplasia, unicornuate, didelphys, bicornuate, septate, arcuate, and diethylstilbestrol (DES) drug-related uterus. In cases of complex anomalies that defy classification, MRI allows detailed depiction of all components of the anatomical abnormality, allowing for proper management and surgical planning. (orig.)

  16. Evaluation of Gas, Oil and Wood Pellet Fueled Residential Heating System Emissions Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, R.

    2009-12-01

    This study has measured the emissions from a wide range of heating equipment burning different fuels including several liquid fuel options, utility supplied natural gas and wood pellet resources. The major effort was placed on generating a database for the mass emission rate of fine particulates (PM 2.5) for the various fuel types studied. The fine particulates or PM 2.5 (less than 2.5 microns in size) were measured using a dilution tunnel technique following the method described in US EPA CTM-039. The PM 2.5 emission results are expressed in several units for the benefit of scientists, engineers and administrators. The measurements of gaseous emissions of O{sub 2}, CO{sub 2}, CO, NO{sub x} and SO{sub 2} were made using a combustion analyzer based on electrochemical cells These measurements are presented for each of the residential heating systems tested. This analyzer also provides a steady state efficiency based on stack gas and temperature measurements and these values are included in the report. The gaseous results are within the ranges expected from prior emission studies with the enhancement of expanding these measurements to fuels not available to earlier researchers. Based on measured excess air levels and ultimate analysis of the fuel's chemical composition the gaseous emission results are as expected and fall within the range provided for emission factors contained in the US-EPA AP 42, Emission Factors Volume I, Fifth Edition. Since there were no unexpected findings in these gaseous measurements, the bulk of the report is centered on the emissions of fine particulates, or PM 2.5. The fine particulate (PM 2.5) results for the liquid fuel fired heating systems indicate a very strong linear relationship between the fine particulate emissions and the sulfur content of the liquid fuels being studied. This is illustrated by the plot contained in the first figure on the next page which clearly illustrates the linear relationship between the measured mass of

  17. Duct Leakage Modeling in EnergyPlus and Analysis of Energy Savings from Implementing SAV with InCITeTM

    Energy Technology Data Exchange (ETDEWEB)

    Wray, Craig; Sherman, Max

    2010-03-01

    This project addressed two significant deficiencies in air-handling systems for large commercial building: duct leakage and duct static pressure reset. Both constitute significant energy reduction opportunities for these buildings. The overall project goal is to bridge the gaps in current duct performance modeling capabilities, and to expand our understanding of air-handling system performance in California large commercial buildings. The purpose of this project is to provide technical support for the implementation of a duct leakage modeling capability in EnergyPlus, to demonstrate the capabilities of the new model, and to carry out analyses of field measurements intended to demonstrate the energy saving potential of the SAV with InCITeTM duct static pressure reset (SPR) technology. A new duct leakage model has been successfully implemented in EnergyPlus, which will enable simulation users to assess the impacts of leakage on whole-building energy use and operation in a coupled manner. This feature also provides a foundation to support code change proposals and compliance analyses related to Title 24 where duct leakage is an issue. Our example simulations continue to show that leaky ducts substantially increase fan power: 10percent upstream and 10percent downstream leakage increases supply fan power 30percent on average compared to a tight duct system (2.5percent upstream and 2.5percent downstream leakage). Much of this increase is related to the upstream leakage rather than to the downstream leakage. This does not mean, however, that downstream leakage is unimportant. Our simulations also demonstrate that ceiling heat transfer is a significant effect that needs to be included when assessing the impacts of duct leakage in large commercial buildings. This is not particularly surprising, given that ?ceiling regain? issues have already been included in residential analyses as long as a decade ago (e.g., ASHRAE Standard 152); mainstream simulation programs that are

  18. Control strategies and cycling demands for Li-ion storage batteries in residential micro-cogeneration systems

    International Nuclear Information System (INIS)

    Darcovich, K.; Kenney, B.; MacNeil, D.D.; Armstrong, M.M.

    2015-01-01

    Highlights: • Canadian home energy system modeled with PV, ICE CHP, battery and power grid. • Battery function is modeled on fundamental electrochemical principles. • Techno-economics of control strategies assessed. • Impact of control strategies battery cycles is developed for wear analysis. • Non-monotonic nature of battery cycles with transient renewables is discussed. - Abstract: Energy storage units have become important components in residential micro-cogeneration (MCG) systems. As MCG systems are often connected to single residences or buildings in a wide variety of settings, they are frequently unique and highly customized. Lithium-ion batteries have recently gained some profile as energy storage units of choice, because of their good capacity, high efficiency, robustness and ability to meet the demands of typical residential electrical loads. In the present work, modeled scenarios are explored which examine the performance of a MCG system with an internal combustion engine, photovoltaic input and a Li-ion storage battery. An electricity demand profile from new data collected in Ottawa, Canada is used to provide a full year energy use context for the analyses. The demands placed on the battery are examined to assess the suitability of the battery size and performance, as well as control related functionalities which reveal significantly varying battery use, and led to a quantitative expression for equivalent cycles. The energy use simulations are derived from electrochemical fundamentals adapted for a larger battery pack. Simulation output provides the basis for techno-economic commentary on how to assess large-scale Li-ion batteries for effective electrical storage purposes in MCG systems, and the impact of the nature of the control strategy on the battery service life

  19. Optimal Design and Operation of A Syngas-fuelled SOFC Micro-CHP System for Residential Applications in Different Climate Zones in China

    DEFF Research Database (Denmark)

    Yang, Wenyuan; Liso, Vincenzo; Zhao, Yingru

    2013-01-01

    Energy consumption in residential sector can be considerably reduced by enhancing the efficiency of energy supply. Fuel cell-based residential micro-CHP systems are expected to be one of the most promising technologies because of their high efficiency and low environmental impact. Since the design...... heat-to-power load ratio. Therefore, the aim of this study is to investigate the optimal design and operation of a syngas-fuelled SOFC micro-CHP system for small households located in five different climate zones in China. The ability of the micro-CHP to cover the heat and electricity demand of a 70m2...... single-family household with an average number of occupants of 3 is evaluated. Detailed model of the micro-CHP unit coupled with a hot water storage tank and an auxiliary boiler is developed. A transient model of the hot water storage tank is used to take into account the effect of peak residential heat...

  20. Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system

    Science.gov (United States)

    Lannes, Nils; Eppler, Elisabeth; Etemad, Samar; Yotovski, Peter; Filgueira, Luis

    2017-01-01

    Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way. PMID:29371994

  1. Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Marine Climates; January 2006 - December 2006

    Energy Technology Data Exchange (ETDEWEB)

    Building America Industrialized Housing Partnership (BAIHP); Building Industry Research Alliance (BIRA); Building Science Consortium (BSC); Consortium for Advanced Residential Buildings (CARB); Davis Energy Group (DEG); IBACOS; National Association of Home Builders Research Center (NAHBRC); National Renewable Energy Laboratory (NREL)

    2006-12-01

    The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Marine Climate Region on a cost neutral basis.

  2. Feasibility study of a hybrid renewable energy system with geothermal and solar heat sources for residential buildings in South Korea

    International Nuclear Information System (INIS)

    Kim, Young Ju; Woo, Nam Sub; Jang, Sung Cheol; Choi, Jeong Ju

    2013-01-01

    This study investigates the economic feasibility of a hybrid renewable energy system (HRES) that uses geothermal and solar heat sources for water heating, space heating, and space cooling in a residential building in Korea. A small-scale HRES consists of a geothermal heat pump for heating and cooling, solar collectors for hot water, a gas-fired backup boiler, and incidental facilities. To determine whether the Hares will produce any economic benefits for homeowners, an economic analysis is conducted to compare the Hares with conventional methods of space heating and cooling in Korea. The payback period of a small-scale Hares is predicted as a maximum of 9 yrs by life cycle costing based on a performance index compared with conventional systems. However, the payback period of large-scale HRES above 400 RT is 6 yrs to 7 yrs.

  3. 46 CFR 116.610 - Ventilation ducts.

    Science.gov (United States)

    2010-10-01

    ... served by the ventilation duct for shutting off the passage of air through the ventilation duct in the... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation ducts. 116.610 Section 116.610 Shipping... Ventilation § 116.610 Ventilation ducts. (a) For the purposes of this section, a ventilation duct includes any...

  4. Design of a Reliable Hybrid (PV/Diesel Power System with Energy Storage in Batteries for Remote Residential Home

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2016-01-01

    Full Text Available This paper reports the experience acquired with a photovoltaic (PV hybrid system simulated as an alternative to diesel system for a residential home located in Southern Nigeria. The hybrid system was designed to overcome the problem of climate change, to ensure a reliable supply without interruption, and to improve the overall system efficiency (by the integration of the battery bank. The system design philosophy was to maximize simplicity; hence, the system was sized using conventional simulation tool and representative insolation data. The system includes a 15 kW PV array, 21.6 kWh (3600 Ah worth of battery storage, and a 5.4 kW (6.8 kVA generator. The paper features a detailed analysis of the energy flows through the system and quantifies all losses caused by PV charge controller, battery storage round-trip, rectifier, and inverter conversions. In addition, simulation was run to compare PV/diesel/battery with diesel/battery and the results show that the capital cost of a PV/diesel hybrid solution with batteries is nearly three times higher than that of a generator and battery combination, but the net present cost, representing cost over the lifetime of the system, is less than one-half of the generator and battery combination.

  5. Measure Guideline: Summary of Interior Ducts in New Construction, Including an Efficient, Affordable Method to Install Fur-Down Interior Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Beal, D.; McIlvaine , J.; Fonorow, K.; Martin, E.

    2011-11-01

    This document illustrates guidelines for the efficient installation of interior duct systems in new housing, including the fur-up chase method, the fur-down chase method, and interior ducts positioned in sealed attics or sealed crawl spaces. This document illustrates guidelines for the efficient installation of interior duct systems in new housing. Interior ducts result from bringing the duct work inside a home's thermal and air barrier. Architects, designers, builders, and new home buyers should thoroughly investigate any opportunity for energy savings that is as easy to implement during construction, such as the opportunity to construct interior duct work. In addition to enhanced energy efficiency, interior ductwork results in other important advantages, such as improved indoor air quality, increased system durability and increased homeowner comfort. While the advantages of well-designed and constructed interior duct systems are recognized, the implementation of this approach has not gained a significant market acceptance. This guideline describes a variety of methods to create interior ducts including the fur-up chase method, the fur-down chase method, and interior ducts positioned in sealed attics or sealed crawl spaces. As communication of the intent of an interior duct system, and collaboration on its construction are paramount to success, this guideline details the critical design, planning, construction, inspection, and verification steps that must be taken. Involved in this process are individuals from the design team; sales/marketing team; and mechanical, insulation, plumbing, electrical, framing, drywall and solar contractors.

  6. End use technology choice in the National Energy Modeling System (NEMS): An analysis of the residential and commercial building sectors

    International Nuclear Information System (INIS)

    Wilkerson, Jordan T.; Cullenward, Danny; Davidian, Danielle; Weyant, John P.

    2013-01-01

    The National Energy Modeling System (NEMS) is arguably the most influential energy model in the United States. The U.S. Energy Information Administration uses NEMS to generate the federal government's annual long-term forecast of national energy consumption and to evaluate prospective federal energy policies. NEMS is considered such a standard tool that other models are calibrated to its forecasts, in both government and academic practice. As a result, NEMS has a significant influence over expert opinions of plausible energy futures. NEMS is a massively detailed model whose inner workings, despite its prominence, receive relatively scant critical attention. This paper analyzes how NEMS projects energy demand in the residential and commercial sectors. In particular, we focus on the role of consumers' preferences and financial constraints, investigating how consumers choose appliances and other end-use technologies. We identify conceptual issues in the approach the model takes to the same question across both sectors. Running the model with a range of consumer preferences, we estimate the extent to which this issue impacts projected consumption relative to the baseline model forecast for final energy demand in the year 2035. In the residential sector, the impact ranges from a decrease of 0.73 quads (− 6.0%) to an increase of 0.24 quads (+ 2.0%). In the commercial sector, the impact ranges from a decrease of 1.0 quads (− 9.0%) to an increase of 0.99 quads (+ 9.0%). - Highlights: • This paper examines the impact of consumer preferences on final energy in the Commercial and Residential sectors of the National Energy Modeling System (NEMS). • We describe the conceptual and empirical basis for modeling consumer technology choice in NEMS. • We offer a range of alternative parameters to show the energy demand sensitivity to technology choice. • We show there are significant potential savings available in both building sectors. • Because the model uses its own

  7. Application analysis of solar total energy systems to the residential sector. Volume III, conceptual design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    The objective of the work described in this volume was to conceptualize suitable designs for solar total energy systems for the following residential market segments: single-family detached homes, single-family attached units (townhouses), low-rise apartments, and high-rise apartments. Conceptual designs for the total energy systems are based on parabolic trough collectors in conjunction with a 100 kWe organic Rankine cycle heat engine or a flat-plate, water-cooled photovoltaic array. The ORC-based systems are designed to operate as either independent (stand alone) systems that burn fossil fuel for backup electricity or as systems that purchase electricity from a utility grid for electrical backup. The ORC designs are classified as (1) a high temperature system designed to operate at 600/sup 0/F and (2) a low temperature system designed to operate at 300/sup 0/F. The 600/sup 0/F ORC system that purchases grid electricity as backup utilizes the thermal tracking principle and the 300/sup 0/F ORC system tracks the combined thermal and electrical loads. Reject heat from the condenser supplies thermal energy for heating and cooling. All of the ORC systems utilize fossil fuel boilers to supply backup thermal energy to both the primary (electrical generating) cycle and the secondary (thermal) cycle. Space heating is supplied by a central hot water (hydronic) system and a central absorption chiller supplies the space cooling loads. A central hot water system supplies domestic hot water. The photovoltaic system uses a central electrical vapor compression air conditioning system for space cooling, with space heating and domestic hot water provided by reject heat from the water-cooled array. All of the systems incorporate low temperature thermal storage (based on water as the storage medium) and lead--acid battery storage for electricity; in addition, the 600/sup 0/F ORC system uses a therminol-rock high temperature storage for the primary cycle. (WHK)

  8. Are Ducted Mini-Splits Worth It?

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, Jonathan M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Maguire, Jeffrey B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Metzger, Cheryn E. [Pacific Northwest National Laboratory; Zhang, Jason [Pacific Northwest National Laboratory

    2018-02-01

    Ducted mini-split heat pumps are gaining popularity in some regions of the country due to their energy-efficient specifications and their ability to be hidden from sight. Although product and install costs are typically higher than the ductless mini-split heat pumps, this technology is well worth the premium for some homeowners who do not like to see an indoor unit in their living area. Due to the interest in this technology by local utilities and homeowners, the Bonneville Power Administration (BPA) has funded the Pacific Northwest National Laboratory (PNNL) and the National Renewable Energy Laboratory (NREL) to develop capabilities within the Building Energy Optimization (BEopt) tool to model ducted mini-split heat pumps. After the fundamental capabilities were added, energy-use results could be compared to other technologies that were already in BEopt, such as zonal electric resistance heat, central air source heat pumps, and ductless mini-split heat pumps. Each of these technologies was then compared using five prototype configurations in three different BPA heating zones to determine how the ducted mini-split technology would perform under different scenarios. The result of this project was a set of EnergyPlus models representing the various prototype configurations in each climate zone. Overall, the ducted mini-split heat pumps saved about 33-60% compared to zonal electric resistance heat (with window AC systems modeled in the summer). The results also showed that the ducted mini-split systems used about 4% more energy than the ductless mini-split systems, which saved about 37-64% compared to electric zonal heat (depending on the prototype and climate).

  9. COMPREHENSIVE DIAGNOSTIC AND IMPROVEMENT TOOLS FOR HVAC-SYSTEM INSTALLATIONS IN LIGHT COMMERCIAL BUILDINGS

    Energy Technology Data Exchange (ETDEWEB)

    Abram Conant; Mark Modera; Joe Pira; John Proctor; Mike Gebbie

    2004-10-31

    Proctor Engineering Group, Ltd. (PEG) and Carrier-Aeroseal LLP performed an investigation of opportunities for improving air conditioning and heating system performance in existing light commercial buildings. Comprehensive diagnostic and improvement tools were created to address equipment performance parameters (including airflow, refrigerant charge, and economizer operation), duct-system performance (including duct leakage, zonal flows and thermal-energy delivery), and combustion appliance safety within these buildings. This investigation, sponsored by the National Energy Technology Laboratory, a division of the U.S. Department of Energy, involved collaboration between PEG and Aeroseal in order to refine three technologies previously developed for the residential market: (1) an aerosol-based duct sealing technology that allows the ducts to be sealed remotely (i.e., without removing the ceiling tiles), (2) a computer-driven diagnostic and improvement-tracking tool for residential duct installations, and (3) an integrated diagnosis verification and customer satisfaction system utilizing a combined computer/human expert system for HVAC performance. Prior to this work the aerosol-sealing technology was virtually untested in the light commercial sector--mostly because the savings potential and practicality of this or any other type of duct sealing had not been documented. Based upon the field experiences of PEG and Aeroseal, the overall product was tailored to suit the skill sets of typical HVAC-contractor personnel.

  10. An energy integrated, multi-microgrid, MILP (mixed-integer linear programming) approach for residential distributed energy system planning – A South Australian case-study

    International Nuclear Information System (INIS)

    Wouters, Carmen; Fraga, Eric S.; James, Adrian M.

    2015-01-01

    The integration of distributed generation units and microgrids in the current grid infrastructure requires an efficient and cost effective local energy system design. A mixed-integer linear programming model is presented to identify such optimal design. The electricity as well as the space heating and cooling demands of a small residential neighbourhood are satisfied through the consideration and combined use of distributed generation technologies, thermal units and energy storage with an optional interconnection with the central grid. Moreover, energy integration is allowed in the form of both optimised pipeline networks and microgrid operation. The objective is to minimise the total annualised cost of the system to meet its yearly energy demand. The model integrates the operational characteristics and constraints of the different technologies for several scenarios in a South Australian setting and is implemented in GAMS. The impact of energy integration is analysed, leading to the identification of key components for residential energy systems. Additionally, a multi-microgrid concept is introduced to allow for local clustering of households within neighbourhoods. The robustness of the model is shown through sensitivity analysis, up-scaling and an effort to address the variability of solar irradiation. - Highlights: • Distributed energy system planning is employed on a small residential scale. • Full energy integration is employed based on microgrid operation and tri-generation. • An MILP for local clustering of households in multi-microgrids is developed. • Micro combined heat and power units are key components for residential microgrids

  11. Intrahepatic transposition of bile ducts.

    Science.gov (United States)

    Delić, Jasmin; Savković, Admedina; Isaković, Eldar; Marković, Sergije; Bajtarevic, Alma; Denjalić, Amir

    2012-01-01

    Objective. To describe the intrahepatic bile duct transposition (anatomical variation occurring in intrahepatic ducts) and to determine the frequency of this variation. Material and Methods. The researches were performed randomly on 100 livers of adults, both sexes. Main research methods were anatomical macrodissection. As a criterion for determination of variations in some parts of bile tree, we used the classification of Segmentatio hepatis according to Couinaud (1957) according to Terminologia Anatomica, Thieme Stuugart: Federative Committee on Anatomical Terminology, 1988. Results. Intrahepatic transposition of bile ducts was found in two cases (2%), out of total examined cases (100): right-left transposition (right segmental bile duct, originating from the segment VIII, joins the left liver duct-ductus hepaticus sinister) and left-right intrahepatic transposition (left segmental bile duct originating from the segment IV ends in right liver duct-ductus hepaticus dexter). Conclusion. Safety and success in liver transplantation to great extent depends on knowledge of anatomy and some common embryological anomalies in bile tree. Variations in bile tree were found in 24-43% of cases, out of which 1-22% are the variations of intrahepatic bile ducts. Therefore, good knowledge on ductal anatomy enables good planning, safe performance of therapeutic and operative procedures, and decreases the risk of intraoperative and postoperative complications.

  12. Economic analysis of photovoltaic systems for the residential market under China's new regulation

    International Nuclear Information System (INIS)

    Rodrigues, Sandy; Chen, Xiaoju; Morgado-Dias, F.

    2017-01-01

    China has recently changed its regulation for producing energy from photovoltaic solar panels in order to encourage the use of the solar resource. This new regulation started with offering subsidies at a national level and this was later followed by local subsidies in addition to the national one. Being a large country, China has regions with good solar exposure and others with poor exposure. Each region has a different electricity price and the energy is purchased based on the Grid Coal Power electricity price that also varies throughout the country. In this work we analyze the economic profitability of different regions considering the solar radiation levels, savings in self-consumption, cash flows from injecting power into the grid and local prices for installations to show that the best return is obtained in the places with better solar radiation or where the electricity price is higher. The regional Feed-In tariffs help to compensate for lower radiation levels but do not make these regions very attractive from an investment perspective. - Highlights: • Summarizes national and local feed in tariffs for China for the residential market. • Provides average local prices for 1 kW, 3 kW and 5 kW photovoltaic installations. • Selects city with best IRR, NPV and DPBP based on prices, subsidies and radiation. • Performs sensitivity analysis to check which parameter has more effect on results.

  13. Expanding photovoltaic penetration with residential distributed generation from hybrid solar photovoltaic and combined heat and power systems

    International Nuclear Information System (INIS)

    Pearce, J.M.

    2009-01-01

    The recent development of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. This paper investigates the potential of deploying a distributed network of PV + CHP hybrid systems in order to increase the PV penetration level in the U.S. The temporal distribution of solar flux, electrical and heating requirements for representative U.S. single family residences were analyzed and the results clearly show that hybridizing CHP with PV can enable additional PV deployment above what is possible with a conventional centralized electric generation system. The technical evolution of such PV + CHP hybrid systems was developed from the present (near market) technology through four generations, which enable high utilization rates of both PV-generated electricity and CHP-generated heat. A method to determine the maximum percent of PV-generated electricity on the grid without energy storage was derived and applied to an example area. The results show that a PV + CHP hybrid system not only has the potential to radically reduce energy waste in the status quo electrical and heating systems, but it also enables the share of solar PV to be expanded by about a factor of five. (author)

  14. The Effect of Electric Load Profiles on the Performance of Off-Grid Residential Hybrid Renewable Energy Systems

    Directory of Open Access Journals (Sweden)

    Stephen Treado

    2015-10-01

    Full Text Available This paper investigates the energy performance of off-grid residential hybrid renewable electric power systems, particularly the effect of electric load profiles on the ability to harvest available solar energy and avoid the consumption of auxiliary energy in the form of propane. The concepts are illustrated by an analysis of the energy performance of electric and propane-fired refrigerators. Off-grid electric power systems frequently incorporate a renewable source, such as wind or solar photovoltaic (PV, with a back-up power provided by a propane fueled motor/generator. Among other design decisions, residential consumers face the choice of employing an electric refrigerator with a conventional vapor compression refrigeration system, or a fuel-fired refrigerator operating as an absorption refrigeration system. One interesting question is whether it is more advantageous from an energy perspective to use electricity to run the refrigerator, which might be provided by some combination of the PV and propane motor/generator, thereby taking advantage of the relatively higher electric refrigerator Coefficient of Performance (COP and free solar energy but having to accept a low electrical conversion efficiency of the motor/generator, or use thermal energy from the combustion of propane to produce the refrigeration effect via an absorption system, albeit with a much lower COP. The analysis is complicated by the fact that most off-grid renewable electrical power systems utilize a battery bank to provide electrical power when it is not available from the wind turbine or PV system, so the state of charge of the battery bank will have a noticeable impact on what energy source is available at any moment in time. Daily electric load profiles combined with variable solar energy input determine the state of charge of the battery bank, with the degree of synchronization between the two being a critical factor in determining performance. The annual energy usage

  15. Customer-economics of residential photovoltaic systems (Part 1): The impact of high renewable energy penetrations on electricity bill savings with net metering

    International Nuclear Information System (INIS)

    Darghouth, Naïm R.; Barbose, Galen; Wiser, Ryan H.

    2014-01-01

    Residential photovoltaic (PV) systems in the US are often compensated at the customer's underlying retail electricity rate through net metering. Given the uncertainty in future retail rates and the inherent links between rates and the customer–economics of behind-the-meter PV, there is growing interest in understanding how potential changes in rates may impact the value of bill savings from PV. In this article, we first use a production cost and capacity expansion model to project California hourly wholesale electricity market prices under two potential electricity market scenarios, including a reference and a 33% renewables scenario. Second, based on the wholesale electricity market prices generated by the model, we develop retail rates (i.e., flat, time-of-use, and real-time pricing) for each future scenario based on standard retail rate design principles. Finally, based on these retail rates, the bill savings from PV is estimated for 226 California residential customers under two types of net metering, for each scenario. We find that high renewable penetrations can drive substantial changes in residential retail rates and that these changes, together with variations in retail rate structures and PV compensation mechanisms, interact to place substantial uncertainty on the future value of bill savings from residential PV. - Highlights: • We investigate the impact of high renewables on customer economics of solar. • We model three types of residential retail electricity rates. • Based on the rates, we calculate the bill savings from photovoltaic (PV) generation. • High renewables penetration can lead to lower bill savings with time-varying rates. • There is substantial uncertainty in the future bill savings from residential PV

  16. Escaping from Flatland: clinical and biological aspects of human mammary duct anatomy in three dimensions.

    Science.gov (United States)

    Going, James J; Moffat, David F

    2004-05-01

    Accurate knowledge of breast duct anatomy in three dimensions is needed to understand normal breast development, how intraepithelial neoplasia may spread through a breast, and the potential for diagnostic and therapeutic access to breast parenchyma via the nipple. This paper reports three related exploratory studies. In study 1, the median number of milk-collecting ducts in the nipple was determined in 72 breasts excised for cancer; in study 2, the volumes of all 20 complete duct systems ("lobes") in an autopsy breast were measured from 2 mm serial "subgross" sections; and in study 3, a 3D digital model of all collecting ducts in a mastectomy nipple was made from 68 100 micro m serial sections. The mastectomy nipples contained 11-48 central ducts (median 27, inter-quartile range 21-30). In the autopsy breast, the largest "lobe" drained 23% of breast volume; half of the breast was drained by three ducts and 75% by the largest six. Conversely, eight small duct systems together accounted for only 1.6% of breast volume. The 3D model of the nipple revealed three distinct nipple duct populations. Seven ducts maintained a wide lumen up to the skin surface (population A); 20 ducts tapered to a minute lumen at their origin in the vicinity of skin appendages (population B) on the apex of the nipple; and a minor duct population (C) arose around the base of the papilla. Major variations in duct morphology and extent define highly variable territories in which intraepithelial neoplasia could grow. While population A ducts appear accessible to duct endoscopy or lavage, population B and population C ducts may be less accessible. Copyright 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  17. Detailed residential electric determination

    Energy Technology Data Exchange (ETDEWEB)

    1984-06-01

    Data on residential loads has been collected from four residences in real time. The data, measured at 5-second intervals for 53 days of continuous operation, were statistically characterized. An algorithm was developed and incorporated into the modeling code SOLCEL. Performance simulations with SOLCEL using these data as well as previous data collected over longer time intervals indicate that no significant errors in system value are introduced through the use of long-term average data.

  18. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, D. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-01

    A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval.

  19. Effects of explosion-generated shock waves in ducts

    International Nuclear Information System (INIS)

    Busby, M.R.; Kahn, J.E.; Belk, J.P.

    1976-01-01

    An explosion in a space causes an increase in temperature and pressure. To quantify the challenge that will be presented to essential components in a ventilation system, it is necessary to analyze the dynamics of a shock wave generated by an explosion, with attention directed to the propagation of such a wave in a duct. Using the equations of unsteady flow and shock tube theory, a theoretical model has been formulated to provide flow properties behind moving shock waves that have interacted with various changes in duct geometry. Empirical equations have been derived to calculate air pressure, temperature, Mach number, and velocity in a duct following an explosion

  20. Design requirement on KALIMER control rod assembly duct

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, W.; Kang, H. Y.; Nam, C.; Kim, J. O.; Kim, Y. J

    1998-03-01

    This document establishes the design guidelines which are needs for designing the control rod assembly duct of the KALIMER as design requirements. it describes control rod assembly duct of the KALIMER and its requirements that includes functional requirements, performance requirements, interfacing systems, design limits and strength requirements, seismic requirements, structural requirements, environmental requirements, reliability and safety requirements, standard and codes, QA programs, and other requirements. The control rod system consists of three parts, which are drive mechanism, drive-line, and absorber bundle. This report deals with the absorber bundle and its outer duct only because the others are beyond the scope of fuel system design. The guidelines for design requirements intend to be used for an improved design of the control rod assembly duct of the KALIMER. (author). 19 refs.

  1. Design requirement on KALIMER control rod assembly duct

    International Nuclear Information System (INIS)

    Hwang, W.; Kang, H. Y.; Nam, C.; Kim, J. O.; Kim, Y. J.

    1998-03-01

    This document establishes the design guidelines which are needs for designing the control rod assembly duct of the KALIMER as design requirements. it describes control rod assembly duct of the KALIMER and its requirements that includes functional requirements, performance requirements, interfacing systems, design limits and strength requirements, seismic requirements, structural requirements, environmental requirements, reliability and safety requirements, standard and codes, QA programs, and other requirements. The control rod system consists of three parts, which are drive mechanism, drive-line, and absorber bundle. This report deals with the absorber bundle and its outer duct only because the others are beyond the scope of fuel system design. The guidelines for design requirements intend to be used for an improved design of the control rod assembly duct of the KALIMER. (author). 19 refs

  2. Raman Scattering Proof-of-Concept Investigation to Detect Particle Phase in the Propulsion System Lab (PSL) Icing Duct

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses a proof-of-concept study using Raman Scattering to distinguish both the particle phase and particle temperature in the Propulsion System Lab...

  3. Effect of heat recovery water heater system on the performance of residential split air conditioner using hydrocarbon refrigerant (HCR22)

    Science.gov (United States)

    Aziz, A.; Thalal; Amri, I.; Herisiswanto; Mainil, A. K.

    2017-09-01

    This This paper presents the performance of residential split air conditioner (RSAC) using hydrocarbon refrigerant (HCR22) as the effect on the use of heat recovery water heater system (HRWHS). In this study, RSAC was modified with addition of dummy condenser (trombone coil type) as heat recovery water heater system (HRWHS). This HRWHS is installed between a compressor and a condenser by absorbing a part of condenser waste heat. The results show that RSAC with HRWHS is adequate to generate hot water with the temperature range about 46.58˚C - 48.81˚C when compared to without HRWHS and the use of dummy condenser does not give significant effect to the split air conditioner performance. When the use of HRWHS, the refrigerant charge has increase about 19.05%, the compressor power consumption has slightly increase about 1.42% where cooling capacity almost the same with slightly different about 0.39%. The condenser heat rejection is lower about 2.68% and the COP has slightly increased about 1.05% when compared to without HRWHS. The use of HRWHS provide free hot water, it means there is energy saving for heating water without negative impact to the system performance of RSAC.

  4. Uncertainty analysis of daily potable water demand on the performance evaluation of rainwater harvesting systems in residential buildings.

    Science.gov (United States)

    Silva, Arthur Santos; Ghisi, Enedir

    2016-09-15

    The objective of this paper is to perform a sensitivity analysis of design variables and an uncertainty analysis of daily potable water demand to evaluate the performance of rainwater harvesting systems in residential buildings. Eight cities in Brazil with different rainfall patterns were analysed. A numeric experiment was performed by means of computer simulation of rainwater harvesting. A sensitivity analysis was performed using variance-based indices for identifying the most important design parameters for rainwater harvesting systems when assessing the potential for potable water savings and underground tank capacity sizing. The uncertainty analysis was performed for different scenarios of potable water demand with stochastic variations in a normal distribution with different coefficients of variation throughout the simulated period. The results have shown that different design variables, such as potable water demand, number of occupants, rainwater demand, and roof area are important for obtaining the ideal underground tank capacity and estimating the potential for potable water savings. The stochastic variations on the potable water demand caused amplitudes of up to 4.8% on the potential for potable water savings and 9.4% on the ideal underground tank capacity. Average amplitudes were quite low for all cities. However, some combinations of parameters resulted in large amplitude of uncertainty and difference from uniform distribution for tank capacities and potential for potable water savings. Stochastic potable water demand generated low uncertainties in the performance evaluation of rainwater harvesting systems; therefore, uniform distribution could be used in computer simulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Effectiveness of duct sealing and duct insulation in multi-family buildings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Karins, N.H.; Tuluca, A.; Modera, M.

    1997-07-01

    This research investigated the cost-effectiveness of sealing and insulating the accessible portions of duct systems exposed to unconditioned areas in multifamily housing. Airflow and temperature measurements were performed in 25 apartments served by 10 systems a 9 multi-family properties. The measurements were performed before and after each retrofit, and included apartment airflow (supply and return), duct system temperatures, system fan flow and duct leakage area. The costs for each retrofit were recorded. The data were analyzed and used to develop a prototypical multifamily house. This prototype was used in energy simulations (DOE-2.1E) and air infiltration simulations (COMIS 2.1). The simulations were performed for two climates: New York City and Albany. In each climate, one simulation was performed assuming the basement was tight, and another assuming the basement was leaky. Simulation results and average retrofit costs were used to calculate cost-effectiveness. The results of the analysis indicate that sealing leaks of the accessible ductwork is cost-effective under all conditions simulated (simple payback was between 3 and 4 years). Insulating the accessible ductwork, however, is only cost-effective for buildings with leaky basement, in both climates (simple paybacks were less than 5 years). The simple payback period for insulating the ducts in buildings with tight basements was greater than 10 years, the threshold of cost-effectiveness for this research. 13 refs., 5 figs., 27 tabs.

  6. System integration of marketable subsystems. [for residential solar heating and cooling

    Science.gov (United States)

    1979-01-01

    Progress is reported in the following areas: systems integration of marketable subsystems; development, design, and building of site data acquisition subsystems; development and operation of the central data processing system; operation of the MSFC Solar Test Facility; and systems analysis.

  7. U.S. Residential Photovoltaic (PV) System Prices, Q4 2013 Benchmarks: Cash Purchase, Fair Market Value, and Prepaid Lease Transaction Prices

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, C.; James, T. L.; Margolis, R.; Fu, R.; Feldman, D.

    2014-10-01

    The price of photovoltaic (PV) systems in the United States (i.e., the cost to the system owner) has dropped precipitously in recent years, led by substantial reductions in global PV module prices. This report provides a Q4 2013 update for residential PV systems, based on an objective methodology that closely approximates the book value of a PV system. Several cases are benchmarked to represent common variation in business models, labor rates, and module choice. We estimate a weighted-average cash purchase price of $3.29/W for modeled standard-efficiency, polycrystalline-silicon residential PV systems installed in the United States. This is a 46% decline from the 2013-dollar-adjusted price reported in the Q4 2010 benchmark report. In addition, this report frames the cash purchase price in the context of key price metrics relevant to the continually evolving landscape of third-party-owned PV systems by benchmarking the minimum sustainable lease price and the fair market value of residential PV systems.

  8. Assesment of Emerging Renewable Energy-based Cogeneration Systems for nZEB Residential Buildings

    DEFF Research Database (Denmark)

    Carmo, Carolina; Dumont, Olivier; Nielsen, Mads Pagh

    2016-01-01

    Net Zero Energy Buildings (nZEB) imply reduced consumption by means of good insulation, passive strategies and highly efficient energy supply systems. Among others, micro cogeneration systems are considered as one of the system solutions with the highest potential to enable nZEB. These systems en...

  9. Energy Analysis of a Complementary Heating System Combining Solar Energy and Coal for a Rural Residential Building in Northwest China

    Science.gov (United States)

    Zhen, Xiaofei; Abdalla Osman, Yassir Idris; Feng, Rong; Zhang, Xuemin

    2018-01-01

    In order to utilize solar energy to meet the heating demands of a rural residential building during the winter in the northwestern region of China, a hybrid heating system combining solar energy and coal was built. Multiple experiments to monitor its performance were conducted during the winter in 2014 and 2015. In this paper, we analyze the efficiency of the energy utilization of the system and describe a prototype model to determine the thermal efficiency of the coal stove in use. Multiple linear regression was adopted to present the dual function of multiple factors on the daily heat-collecting capacity of the solar water heater; the heat-loss coefficient of the storage tank was detected as well. The prototype model shows that the average thermal efficiency of the stove is 38%, which means that the energy input for the building is divided between the coal and solar energy, 39.5% and 60.5% energy, respectively. Additionally, the allocation of the radiation of solar energy projecting into the collecting area of the solar water heater was obtained which showed 49% loss with optics and 23% with the dissipation of heat, with only 28% being utilized effectively. PMID:29651424

  10. Energy Analysis of a Complementary Heating System Combining Solar Energy and Coal for a Rural Residential Building in Northwest China.

    Science.gov (United States)

    Zhen, Xiaofei; Li, Jinping; Abdalla Osman, Yassir Idris; Feng, Rong; Zhang, Xuemin; Kang, Jian

    2018-01-01

    In order to utilize solar energy to meet the heating demands of a rural residential building during the winter in the northwestern region of China, a hybrid heating system combining solar energy and coal was built. Multiple experiments to monitor its performance were conducted during the winter in 2014 and 2015. In this paper, we analyze the efficiency of the energy utilization of the system and describe a prototype model to determine the thermal efficiency of the coal stove in use. Multiple linear regression was adopted to present the dual function of multiple factors on the daily heat-collecting capacity of the solar water heater; the heat-loss coefficient of the storage tank was detected as well. The prototype model shows that the average thermal efficiency of the stove is 38%, which means that the energy input for the building is divided between the coal and solar energy, 39.5% and 60.5% energy, respectively. Additionally, the allocation of the radiation of solar energy projecting into the collecting area of the solar water heater was obtained which showed 49% loss with optics and 23% with the dissipation of heat, with only 28% being utilized effectively.

  11. Effect of Ducted HPWH on Space-Conditioning and Water Heating Energy Use -- Central Florida Lab Home

    Energy Technology Data Exchange (ETDEWEB)

    Colon, Carlos [Florida Solar Energy Center, Cocoa, FL (United States); Martin, Eric [Florida Solar Energy Center, Cocoa, FL (United States); Parker, Danny [Florida Solar Energy Center, Cocoa, FL (United States)

    2016-11-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWH's) on space conditioning and water heating energy use in residential applications. Two identical HPWH's, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  12. Effect of Ducted HPWH on Space-Conditioning and Water Heating Energy Use -- Central Florida Lab Home

    Energy Technology Data Exchange (ETDEWEB)

    Colon, Carlos [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Martin, Eric [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Parker, Danny [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States)

    2016-11-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWHs) on space conditioning and water heating energy use in residential applications. Two identical HPWHs, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  13. A prospective economic assessment of residential PV self-consumption with batteries and its systemic effects, and the implications for public policies: the French case in 2030

    International Nuclear Information System (INIS)

    Yu, Hyun Jin Julie

    2017-01-01

    Over the last decade, the price of PV modules has fallen largely due to the globalization of the PV sector. If residential PV systems coupled with batteries become economically competitive in the near future, end-users will be willing to switch to the self-consumption of PV electricity instead of using power from the network. If the transition of PV self-consumption in the residential sector occurs massively or suddenly, the national energy system would be faced with a radical change. This article analyses the economic feasibility of French residential PV systems combined with Li-ion batteries in 2030 to anticipate the possible change in future energy systems. It also includes a stakeholder analysis with respect to the PV self-consumption model to analyse the systemic effects of PV integration into the electricity system. Our study provides a theoretical explanation of the impact on the current electricity market and quantifies the expected impact on the most influential stakeholder group. The ultimate objective is to help policy-makers forecast possible scenarios for PV self-consumption so they can prepare for the future transition with strategic actions. By way of conclusion, we discuss the policy implications and elaborate policy recommendations based on the results of this study. (author)

  14. SIZING AND COSTING OPTIMISATION OF A TYPICAL WIND/PV HYBRID ELECTRICITY GENERATION SYSTEM FOR A TYPICAL RESIDENTIAL BUILDING IN URBAN ARMIDALE NSW, AUSTRALIA

    Directory of Open Access Journals (Sweden)

    Yasser Maklad

    2014-04-01

    Full Text Available This study investigates the wind and solar electricity generation availability and potentiality for residential buildings in Armidale NSW, Australia. The main purpose of this study is to design an appropriate wind-PV hybrid system to cover the electricity consumption of typical residential buildings of various occupancy rates and relevant various average electrical daily consumption. In order to do achieve that, monthly average solar irradiance monthly average wind speed historical data observed at weather station belongs to the Australian bureau of meteorology in Armidale town over a fourteen years period from 1997–2010. Simulation of solar photovoltaic panels and wind turbines were conducted to obtain the optimal hybrid system sizing and best efficient with lowest cost. Correlations between the solar and wind power data were carried out on an hourly, daily, and monthly basis. It is shown that the hybrid system can be applied for the efficient and economic utilization of wind and solar renewable energy sources.

  15. Preliminary experimental investigation of a natural gas-fired ORC-based micro-CHP system for residential buildings

    International Nuclear Information System (INIS)

    Farrokhi, M.; Noie, S.H.; Akbarzadeh, A.A.

    2014-01-01

    The continual increases in energy demand and greenhouse gas emissions, call for efficient use of energy resources. Decentralized combined heat and power (CHP) technology provides an alternative for the world to meet and solve energy-related problems including energy shortages, energy supply security, emission control and conservation of energy. This paper presents the preliminary results of an experimental investigation of a natural gas-fired micro-CHP system for residential buildings based on an organic Rankine cycle (ORC). Isopentane was used as the ORC working fluid in consideration of several criteria including its environmentally-friendly characteristics. Experiments were conducted to evaluate the performance of the developed system at different heat source temperatures of nominally 85, 80, 75, 70, and 65 °C. The maximum electrical power output of 77.4 W was generated at heating water entry temperature of 84.1 °C, corresponding to net cycle electrical efficiency of 1.66%. Further work will be done with a view to increasing the cycle electrical efficiency by using more efficient components, in particular the expander and generator. - Highlights: •A natural gas-fired ORC-based micro-scale CHP system has been developed and tested. •The good agreement between the mechanical and gross power validates the assumptions. •A vane expander suits a micro-CHP system based on an organic Rankine cycle. •A vane expander does not suit power generation by a Trilateral Flash Cycle (TFC). •Domestic gas-fired ORC systems may reduce reliance on central power stations

  16. Salivary duct carcinoma.

    Science.gov (United States)

    D'heygere, Emmanuel; Meulemans, Jeroen; Vander Poorten, Vincent

    2018-01-25

    The review puts new information on geno- and phenotype of salivary duct carcinoma (SDC) in the perspective of the updated 2017 WHO classification. The proportion of SDC is increasing. This may be because of a true rise in incidence, but certainly to better diagnostic tests and changed WHO definitions. In this light, a substantial proportion of carcinoma expleomorphic adenoma is now attributed to the category of SDC. 'Low-grade SDC' and 'SDC in-situ' of the former WHO classification, are now named low-grade and high-grade intraductal carcinoma (IDC), respectively. Recent series quantify biologic aggressiveness: perineural growth, vascular invasion, and extracapsular extension in lymph node metastasis are each observed in two out of three patients with SDC. Most patients die within 3 years, but once 5-year disease-free survival is reached, further disease activity is exceptional. The typical molecular biological profile with high human epidermal growth factor receptor 2 and androgen receptor expression is increasingly successfully exploited in clinical trials for advanced SDC. The aggressive SDC is increasingly diagnosed. Despite intensive combined surgery and radiation therapy, many patients recur, for whom new bullets, targeting the molecular biological mechanisms, are the subject of ongoing clinical trials.

  17. Duct Leakage Repeatability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-01

    Duct leakage often needs to be measured to demonstrate compliance with requirements or to determine energy or Indoor Air Quality (IAQ) impacts. Testing is often done using standards such as ASTM E1554 (ASTM 2013) or California Title 24 (California Energy Commission 2013 & 2013b), but there are several choices of methods available within the accepted standards. Determining which method to use or not use requires an evaluation of those methods in the context of the particular needs. Three factors that are important considerations are the cost of the measurement, the accuracy of the measurement and the repeatability of the measurement. The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards.

  18. An optimisation framework for thermal energy storage integration in a residential heat pump heating system

    International Nuclear Information System (INIS)

    Renaldi, R.; Kiprakis, A.; Friedrich, D.

    2017-01-01

    Highlights: • An integrated framework for the optimal design of low carbon heating systems. • Development of a synthetic heat demand model with occupancy profiles. • Linear model of a heat pump with thermal energy storage heating system. • Evaluation of domestic heating system from generally available input parameters. • The lower carbon heating system can be cost competitive with conventional systems. - Abstract: Domestic heating has a large share in the UK total energy consumption and significant contribution to the greenhouse gas emissions since it is mainly fulfilled by fossil fuels. Therefore, decarbonising the heating system is essential and an option to achieve this is by heating system electrification through heat pumps (HP) installation in combination with renewable power generation. A potential increase in performance and flexibility can be achieved by pairing HP with thermal energy storage (TES), which allows the shifting of heat demand to off peak periods or periods with surplus renewable electricity. We present a design and operational optimisation model which is able to assess the performance of HP–TES relative to conventional heating systems. The optimisation is performed on a synthetic heat demand model which requires only the annual heat demand, temperature and occupancy profiles. The results show that the equipment and operational cost of a HP system without TES are significantly higher than for a conventional system. However, the integration of TES and time-of-use tariffs reduce the operational cost of the HP systems and in combination with the Renewable Heating Incentive make the HP systems cost competitive with conventional systems. The presented demand model and optimisation procedure will enable the design of low carbon district heating systems which integrate the heating system with the variable renewable electricity supply.

  19. Status of the development of hot gas ducts for HTRs

    International Nuclear Information System (INIS)

    Stehle, H.; Klas, E.

    1984-01-01

    In the PNP nuclear process heat system the heat generated in the helium cooled core is transferred to the steam reformer and to the successive steam generator or to the intermediate heat exchanger by the primary helium via suitable hot gas ducts. The heat is carried over to the steam gasifier by the intermediate heat exchanger and a secondary helium loop. In both the primary and the secondary loop, the hot gas ducts are internally insulated by a ceramic fibre insulation to protect the support tube and the pressure housing from the high helium temperatures. A graphite hot gas liner will be used for the coaxial primary duct with an annular gap between support tube and pressure shell for the cold gas counterflow. A metallic hot gas liner will be installed in the secondary duct

  20. Measure Guideline: Buried and/or Encapsulated Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Zoeller, W. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Mantha, P. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2013-08-01

    Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license.

  1. Next-generation heat pump systems in residential buildings and commercial premises; Naesta generations vaermepumpssystem i bostaeder och lokaler

    Energy Technology Data Exchange (ETDEWEB)

    Haglund Stignor, Caroline; Lindahl, Markus; Alsbjer, Markus; Nordman, Roger; Rolfsman, Lennart; Axell, Monica

    2009-07-01

    Summarising, the following conclusions can be drawn from this work. - Installation of a heat pump system is a very efficient way of reducing a building's energy demand without making any greater changes to the building's climate screen, and can therefore assist Sweden's achievement of its energy efficiency improvement targets. - A new generation of cost-effective smaller heat pumps is needed for installation in new detached houses or those being renovated and upgraded. - There also seems to be an excellent market potential for heat pumps that are larger than has previously been common: there should be good prospects for selling them for use in apartment buildings and in commercial or similar premises. - Heat pump installations are particularly competitive in applications where there are simultaneous heating and cooling demands in the property, and also in those cases where heating is required for most of the year and cooling for some other part of the year. If these suggested system arrangements are to be fully realised, there will be a need for further research in certain cases. Particularly, there is a need for research and development of more efficient pumps, fans and speed-controlled compressors in order to get such products on to the market. Performance measurements and follow-up of real systems are needed in order to obtain a clear picture of the efficiency of both present-day and proposed systems. This knowledge is essential for further development of systems, not only for residential buildings but also, even more importantly, for commercial and similar premises. Actual heating and cooling requirements in different types of non-residential premises need to be known more accurately in order to decide how systems should be controlled in order to minimise total energy use. Much indicates that future detached houses will be more energy-efficient, which could have the undesirable result of greater use of direct electric heating, as the investment

  2. A System for Planning and Achieving Comprehensive Health Care in Residential Institutions for the Mentally Retarded.

    Science.gov (United States)

    Decker, Harold A.

    Based on a view of health care intertwining medicine intimately with other components of institutional care, the monograph presents a system of concepts and operating techniques for providing comprehensive health care to institutionalized retardates. Background of the system is explained in terms of its research basis (two studies by the author of…

  3. Analysis of a fuel cell on-site integrated energy system for a residential complex

    Science.gov (United States)

    Simons, S. N.; Maag, W. L.

    1979-01-01

    The energy use and costs of the on-site integrated energy system (OS/IES) which provides electric power from an on-site power plant and recovers heat that would normally be rejected to the environment is compared to a conventional system purchasing electricity from a utility and a phosphoric acid fuel cell powered system. The analysis showed that for a 500-unit apartment complex a fuel OS/IES would be about 10% more energy conservative in terms of total coal consumption than a diesel OS/IES system or a conventional system. The fuel cell OS/IES capital costs could be 30 to 55% greater than the diesel OS/IES capital costs for the same life cycle costs. The life cycle cost of a fuel cell OS/IES would be lower than that for a conventional system as long as the cost of electricity is greater than $0.05 to $0.065/kWh. An analysis of several parametric combinations of fuel cell power plant and state-of-art energy recovery systems and annual fuel requirement calculations for four locations were made. It was shown that OS/IES component choices are a major factor in fuel consumption, with the least efficient system using 25% more fuel than the most efficient. Central air conditioning and heat pumps result in minimum fuel consumption while individual air conditioning units increase it, and in general the fuel cell of highest electrical efficiency has the lowest fuel consumption.

  4. Choosing the Right Technologies – A Model for Cost Optimized Design of a Renewable Supply System for Residential Zero Energy Buildings

    DEFF Research Database (Denmark)

    Milan, Christian

    , individual performance models are defined. For small scale residential systems the hot water tank is one of the main components, connecting supply and demand side and acting as a buffer during mismatch periods. For this reason, the developed hot water tank model is rather detailed accounting for three......This work presents a methodology to identify and investigate the cost optimal design of supply systems for Low and Net Zero Energy Buildings with the focus on residential single family houses. A preliminary analysis investigating relevant literature and existing computer tools resulted...... different temperature layers, two different supply and demand loops as well as individual heat losses. It is presented at the end of the technology chapter. Subsequently, the methodology is validated by investigating the output with one single technology at a time and thus the individual performance models...

  5. Development of a solar-powered residential air conditioner: System optimization preliminary specification

    Science.gov (United States)

    Rousseau, J.; Hwang, K. C.

    1975-01-01

    Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

  6. Measure Guideline: Buried and/or Encapsulated Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Zoeller, W.; Mantha, P.

    2013-08-01

    Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. This Building America Measure Guideline synthesizes previously published research on BEDs and provides practical information to builders, contractors, homeowners, policy analysts, building professions, and building scientists. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license. Persons implementing duct system improvements should not go beyond their expertise or qualifications. This guideline provides valuable information for a building industry that has struggled to address ductwork thermal losses in new and existing homes. As building codes strengthen requirements for duct air sealing and insulation, flexibility is needed to address energy efficiency goals. While ductwork in conditioned spaces has been promoted as the panacea for addressing ductwork thermal losses, BEDs installations approach - and sometimes exceed - the performance of ductwork in conditioned spaces.

  7. An Analysis of the Effects of Photovoltaic Energy Systems on Residential Selling Prices in California.

    Energy Technology Data Exchange (ETDEWEB)

    Cappers, Peter; Wiser, Ryan; Thayer, Mark; Hoen, Ben

    2011-04-12

    An increasing number of homes with existing photovoltaic (PV) energy systems have sold in the U.S., yet relatively little research exists that estimates the marginal impacts of those PV systems on the sales price. A clearer understanding of these effects might influence the decisions of homeowners, home buyers and PV home builders. This research analyzes a large dataset of California homes that sold from 2000 through mid-2009 with PV installed. Across a large number of hedonic and repeat sales model specifications and robustness tests, the analysis finds strong evidence that homes with PV systems sold for a premium over comparable homes without. The effects range, on average, from approximately $3.9 to $6.4 per installed watt (DC), with most models coalescing near $5.5/watt, which corresponds to a premium of approximately $17,000 for a 3,100 watt system. The research also shows that, as PV systems age, the premium enjoyed at the time of home sale decreases. Additionally, existing homes with PV systems are found to have commanded a larger sales price premium than new homes with similarly sized PV systems. Reasons for this discrepancy are suggested, yet further research is warranted in this area as well as a number of other areas that are highlighted.

  8. Residential Photovoltaic Energy Systems in California: The Effect on Home Sales Prices

    Energy Technology Data Exchange (ETDEWEB)

    Hoen, Ben; Wiser, Ryan; Thayer, Mark; Cappers, Peter

    2012-04-15

    Relatively little research exists estimating the marginal impacts of photovoltaic (PV) energy systems on home sale prices. Using a large dataset of California homes that sold from 2000 through mid-2009, we find strong evidence, despite a variety of robustness checks, that existing homes with PV systems sold for a premium over comparable homes without PV systems, implying a near full return on investment. Premiums for new homes are found to be considerably lower than those for existing homes, implying, potentially, a tradeoff between price and sales velocity. The results have significant implications for homeowners, builders, appraisers, lenders, and policymakers.

  9. Design and operation of a solar heating and cooling system for a residential size building

    Science.gov (United States)

    Littles, J. W.; Humphries, W. R.; Cody, J. C.

    1978-01-01

    The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner.

  10. Distributed photovoltaic generation in Brazil: An economic viability analysis of small-scale photovoltaic systems in the residential and commercial sectors

    International Nuclear Information System (INIS)

    Holdermann, Claudius; Kissel, Johannes; Beigel, Jürgen

    2014-01-01

    This paper examines the economic viability of small-scale, grid-connected photovoltaics in the Brazilian residential and commercial sectors after the introduction of the net metering regulation in April 2012. This study uses the discounted cash flow method to calculate the specific investment costs that are necessary for photovoltaic systems to be economically viable for each of the 63 distribution networks in Brazil. We compare these values to the system costs that are estimated in the comprehensive study on photovoltaics that was developed by the Brazilian Association of Electric and Electronic Industries (ABINEE). In our calculation, we utilize the current electricity tariffs, including fees and taxes, which we obtained through telephone interviews and publicly available information. We obtained a second important parameter by simulating PV-systems with the program PV ⁎ Sol at the distribution company headquarters' locations. In our base case scenario that reflects the current situation, in none of the distribution networks photovoltaics is economically viable in either the commercial or residential sectors. We improved the environment for grid-connected photovoltaics in our scenarios by assuming both lower PV-system costs and a lower discount rate to determine the effect on photovoltaics viability. - Highlights: • We calculate the economic viability of photovoltaics in the residential and commercial sectors in Brazil. • The PV ⁎ Sol simulations are carried out at the headquarter locations for the 63 distribution companies. • Currently in none of the distribution networks, photovoltaics is economically viable in either the commercial or residential sectors. • We analyze how the variation of the specific investment costs and of the discount rate affects the economic viability

  11. Uncertainties in the Value of Bill Savings from Behind-the-Meter, Residential Photovoltaic Systems: The Roles of Electricity Market Conditions, Retail Rate Design, and Net Metering

    OpenAIRE

    Darghouth, Naim Richard

    2013-01-01

    Net metering has become a widespread policy mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), allowing customers with PV systems to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption. Although net metering is one of the principal drivers for the residential PV market in the U.S., the academic literature on this policy has been sparse and this dissertation co...

  12. Fuzzy logic controller versus classical logic controller for residential hybrid solar-wind-storage energy system

    Energy Technology Data Exchange (ETDEWEB)

    Derrouazin, A., E-mail: derrsid@gmail.com [University Hassiba BenBouali of Chlef, LGEER,Chlef (Algeria); Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); CentraleSupélec, LMOPS, 57070 Metz (France); Aillerie, M., E-mail: aillerie@metz.supelec.fr; Charles, J. P. [Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); CentraleSupélec, LMOPS, 57070 Metz (France); Mekkakia-Maaza, N. [Université des sciences et de la Technologie d’Oran, Mohamed Boudiaf-USTO MB,LMSE, Oran Algérie (Algeria)

    2016-07-25

    Several researches for management of diverse hybrid energy systems and many techniques have been proposed for robustness, savings and environmental purpose. In this work we aim to make a comparative study between two supervision and control techniques: fuzzy and classic logics to manage the hybrid energy system applied for typical housing fed by solar and wind power, with rack of batteries for storage. The system is assisted by the electric grid during energy drop moments. A hydrogen production device is integrated into the system to retrieve surplus energy production from renewable sources for the household purposes, intending the maximum exploitation of these sources over years. The models have been achieved and generated signals for electronic switches command of proposed both techniques are presented and discussed in this paper.

  13. Life cycle cost analysis of solar heating and DHW systems in residential buildings

    International Nuclear Information System (INIS)

    Colombo, R.; Gilliaert, D.

    1992-01-01

    Economic Life Cycle Cost Analysis (ELCCA) is an easy and friendly computer program, IBM compatible for economic evaluation of solar energy system which involves comparison of the capital and operating costs of a conventional system. In this section we would like to suggest the ELCCA-PC program as a new tools using life cycle cost analysis for annual and cumulative cash flow methodology that take into account all future expenses. ELCCA-PC program considers fixed and changeable items that are involved in installing the equipment such as interest of money borrowed, property and income taxes, current energy cost for electricity operating system, maintenance, insurance and fuel costs and other economic operating expenses. Moreover fraction of annual heating load supplied from solar system is considered in this analysis. ECC-PC program determines the yearly outflow of money over the period of an economic analysis that can be converted to a series of equal payments in today's money

  14. STANDALONE PHOTOVOLTAIC SYSTEMS SIZING OPTIMIZATION USING DESIGN SPACE APPROACH: CASE STUDY FOR RESIDENTIAL LIGHTING LOAD

    Directory of Open Access Journals (Sweden)

    D. F. AL RIZA

    2015-07-01

    Full Text Available This paper presents a sizing optimization methodology of panel and battery capacity in a standalone photovoltaic system with lighting load. Performance of the system is identified by performing Loss of Power Supply Probability (LPSP calculation. Input data used for the calculation is the daily weather data and system components parameters. Capital Cost and Life Cycle Cost (LCC is calculated as optimization parameters. Design space for optimum system configuration is identified based on a given LPSP value, Capital Cost and Life Cycle Cost. Excess energy value is used as an over-design indicator in the design space. An economic analysis, including cost of the energy and payback period, for selected configurations are also studied.

  15. Rational designing of the internal water supply system in reconstructed residential buildings of mass standard series

    Directory of Open Access Journals (Sweden)

    Orlov Evgeny

    2018-01-01

    Full Text Available The issues of water supply system reconstruction in mass series buildings are reviewed with consideration of water- and resource saving. Principal points for location of plumbing cells in apartments, arrangement of water devices and wastewater receivers, selection of pipelines for reconstructed water line are described. Comparative analysis of design variants of inner water line before and following reconstruction are given. It was found that applying the developed system design approaches the head losses in the inner water supply line will be significantly decreased as well as the water mains length will be decreased with material and installation saving. Based on the data the conclusions on necessity to review standard arrangement solutions of water supply systems in the reconstructed buildings were made. Recommendations on water loss reduction in the system by installation of special water saving fittings on water devices and touchless faucets.

  16. Fuzzy logic controller versus classical logic controller for residential hybrid solar-wind-storage energy system

    International Nuclear Information System (INIS)

    Derrouazin, A.; Aillerie, M.; Charles, J. P.; Mekkakia-Maaza, N.

    2016-01-01

    Several researches for management of diverse hybrid energy systems and many techniques have been proposed for robustness, savings and environmental purpose. In this work we aim to make a comparative study between two supervision and control techniques: fuzzy and classic logics to manage the hybrid energy system applied for typical housing fed by solar and wind power, with rack of batteries for storage. The system is assisted by the electric grid during energy drop moments. A hydrogen production device is integrated into the system to retrieve surplus energy production from renewable sources for the household purposes, intending the maximum exploitation of these sources over years. The models have been achieved and generated signals for electronic switches command of proposed both techniques are presented and discussed in this paper.

  17. Small Business Voucher CRADA Report: Natural Gas Powered HVAC System for Commercial and Residential Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Betts, Daniel [Be Power Tech, Deerfield Beach, FL (United States); Ally, Moonis Raza [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mudiraj, Shyam [Be Power Tech, Deerfield Beach, FL (United States); Tilghman, Matthew [Be Power Tech, Deerfield Beach, FL (United States); Graham, Matthew [Be Power Tech, Deerfield Beach, FL (United States)

    2017-04-30

    Be Power Tech is commercializing BeCool, the first integrated electricity-producing heating, ventilation, and air conditioning (HVAC) system using a non-vapor compression cycle (VCC), packaged rooftop HVAC unit that also produces base-load electricity, heating, ventilation, and air conditioning. BeCool is a distributed energy resource with energy storage that eliminates the tremendous peak electricity demand associated with commonly used electricity-powered vapor compression air conditioning systems.

  18. Study on pollution control in residential kitchen based on the push-pull ventilation system

    DEFF Research Database (Denmark)

    Zhou, Bin; Chen, Feng; Dong, Zhibo

    2016-01-01

    Highlights •The push-pull ventilation system is proposed to improve IAQ inside kitchen, where air is supplied through slot air curtain and then exhausted through range hood. •CO2 reduction efficiency with application of air curtain in experiment and simulation in breathing zone was 23.7% and 23.......1%, respectively. •By orthogonal method, the influence of factors on pollution control of the push-pull ventilation system was presented....

  19. Greywater Reuse System Design and Economic Analysis for Residential Buildings in Taiwan

    Directory of Open Access Journals (Sweden)

    Yi-Kai Juan

    2016-11-01

    Full Text Available The concept of greywater recycling and reuse has gradually become one of the most important strategies in water stressed countries. Due to a high population density and uneven rainfall distribution, the annual average rainfall distribution per capita in Taiwan is one fifth of the global average, which makes Taiwan a seriously water-stressed country. This study used the unit of a family of four as the target and reexamined the zoning concepts of water usage areas, followed by integrating pipeline configuration, water storage design and a filtering system to propose an Interior Customized Greywater System (ICGS which is based on the application for the family unit. This system can be customized and flexibly adjusted according to household space. In order to verify the feasibility and viability of system, this study performed system configuration and design based on real cases and proposed three scenarios to simulate a 20 year life cycle for cost economic analysis. The result reveals that this system has a minimum payback period of 4 years and provides investment incentives. For regions or countries which have higher water cost or are more water stressed, ICGS can significantly improve the processing and utilization of water.

  20. Development of Innovative Heating and Cooling Systems Using Renewable Energy Sources for Non-Residential Buildings

    Directory of Open Access Journals (Sweden)

    Cinzia Buratti

    2013-10-01

    Full Text Available Industrial and commercial areas are synonymous with high energy consumption, both for heating/cooling and electric power requirements, which are in general associated to a massive use of fossil fuels producing consequent greenhouse gas emissions. Two pilot systems, co-funded by the Italian Ministry for the Environment, have been created to upgrade the heating/cooling systems of two existing buildings on the largest industrial estate in Umbria, Italy. The upgrade was specifically designed to improve the system efficiency and to cover the overall energy which needs with renewable energy resources. In both cases a solar photovoltaic plant provides the required electric power. The first system features a geothermal heat pump with an innovative layout: a heat-storage water tank, buried just below ground level, allows a significant reduction of the geothermal unit size, hence requiring fewer and/or shorter boreholes (up to 60%–70%. In the other system a biomass boiler is coupled with an absorption chiller machine, controlling the indoor air temperature in both summer and winter. In this case, lower electricity consumption, if compared to an electric compression chiller, is obtained. The first results of the monitoring of summer cooling are presented and an evaluation of the performance of the two pilot systems is given.

  1. Techno-ecological synergy as a path toward sustainability of a North American residential system.

    Science.gov (United States)

    Urban, Robert A; Bakshi, Bhavik R

    2013-02-19

    For any human-designed system to be sustainable, ecosystem services that support it must be readily available. This work explicitly accounts for this dependence by designing synergies between technological and ecological systems. The resulting techno-ecological network mimics nature at the systems level, can stay within ecological constraints, and can identify novel designs that are economically and environmentally attractive that may not be found by the traditional design focus on technological options. This approach is showcased by designing synergies for a typical American suburban home at local and life cycle scales. The objectives considered are carbon emissions, water withdrawal, and cost savings. Systems included in the design optimization include typical ecosystems in suburban yards: lawn, trees, water reservoirs, and a vegetable garden; technological systems: heating, air conditioning, faucets, solar panels, etc.; and behavioral variables: heating and cooling set points. The ecological and behavioral design variables are found to have a significant effect on the three objectives, in some cases rivaling and exceeding the effect of traditional technological options. These results indicate the importance and benefits of explicitly including ecosystems in the design of sustainable systems, something that is rarely done in existing methods.

  2. Hybrid renewable energy system application for electricity and heat supply of a residential building

    Directory of Open Access Journals (Sweden)

    Nakomčić-Smaragdakis Branka B.

    2016-01-01

    Full Text Available Renewable and distributed energy systems could provide a solution to the burning issue of reliable and clean supply of energy, having in mind current state and future predictions for population growth and fossil fuel scarcity. Hybrid renewable energy systems are novelty in Serbia and warrant further detailed research. The aim of this paper is to analyze the application of renewable energy sources(RES for electricity and heat supply of a typical household in Serbia, as well as the cost-effectiveness of the proposed system. The influence of feed-in tariff change on the value of the investment is analyzed. Small, grid-connected hybrid system (for energy supply of a standard household, consisting of geothermal heat pump for heating/cooling, solar photovoltaic panels and small wind turbine for power supply is analyzed as a case study. System analysis was conducted with the help of RETScreen software. Results of techno-economics analysis have shown that investing in geothermal heat pump and photovoltaic panels is cost-effective, while that is not the case with small wind turbine.

  3. Uncertainties in the Value of Bill Savings from Behind-the-Meter, Residential Photovoltaic Systems: The Roles of Electricity Market Conditions, Retail Rate Design, and Net Metering

    Science.gov (United States)

    Darghouth, Naim Richard

    Net metering has become a widespread policy mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), allowing customers with PV systems to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption. Although net metering is one of the principal drivers for the residential PV market in the U.S., the academic literature on this policy has been sparse and this dissertation contributes to this emerging body of literature. This dissertation explores the linkages between the availability of net metering, wholesale electricity market conditions, retail rates, and the residential bill savings from behind-the-meter PV systems. First, I examine the value of the bill savings that customers receive under net metering and alternatives to net metering, and the associated role of retail rate design, based on current rates and a sample of approximately two hundred residential customers of California's two largest electric utilities. I find that the bill savings per kWh of PV electricity generated varies greatly, largely attributable to the increasing block structure of the California utilities' residential retail rates. I also find that net metering provides significantly greater bill savings than alternative compensation mechanisms based on avoided costs. However, retail electricity rates may shift as wholesale electricity market conditions change. I then investigate a potential change in market conditions -- increased solar PV penetrations -- on wholesale prices in the short-term based on the merit-order effect. This demonstrates the potential price effects of changes in market conditions, but also points to a number of methodological shortcomings of this method, motivating my usage of a long-term capacity investment and economic dispatch model to examine wholesale price effects of various wholesale market scenarios in the subsequent analysis. By developing

  4. A cost optimization model for 100% renewable residential energy supply systems

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2012-01-01

    The concept of net zero energy buildings (Net ZEB) has received increased attention throughout the last years. A well adapted and optimized design of the energy supply system is crucial for the performance of these buildings. To achieve this, a holistic approach is needed which accounts for the i......The concept of net zero energy buildings (Net ZEB) has received increased attention throughout the last years. A well adapted and optimized design of the energy supply system is crucial for the performance of these buildings. To achieve this, a holistic approach is needed which accounts......'s involving on-site production of heat and electricity in combination with electricity exchanged with the public grid. The model is based on linear programming and determines the optimal capacities for each relevant supply technology in terms of the overall system costs. It has been successfully applied...

  5. An Analysis of the Effects of Residential Photovoltaic Energy Systems on Home Sales Prices in California

    Energy Technology Data Exchange (ETDEWEB)

    Hoen, Ben; Cappers, Peter; Wiser, Ryan; Thayer, Mark

    2011-04-19

    An increasing number of homes in the U.S. have sold with photovoltaic (PV) energy systems installed at the time of sale, yet relatively little research exists that estimates the marginal impacts of those PV systems on home sale prices. A clearer understanding of these possible impacts might influence the decisions of homeowners considering the installation of a PV system, homebuyers considering the purchase of a home with PV already installed, and new home builders considering including PV as an optional or standard product on their homes. This research analyzes a large dataset of California homes that sold from 2000 through mid-2009 with PV installed. It finds strong evidence that homes with PV systems sold for a premium over comparable homes without PV systems during this time frame. Estimates for this premium expressed in dollars per watt of installed PV range, on average, from roughly $4 to $5.5/watt across a large number of hedonic and repeat sales model specifications and robustness tests. When expressed as a ratio of the sales price premium of PV to estimated annual energy cost savings associated with PV, an average ratio of 14:1 to 19:1 can be calculated; these results are consistent with those of the more-extensive existing literature on the impact of energy efficiency on sales prices. When the data are split among new and existing homes, however, PV system premiums are markedly affected. New homes with PV show premiums of $2.3-2.6/watt, while existing homes with PV show premiums of more than $6/watt. Reasons for this discrepancy are suggested, yet further research is warranted. A number of other areas where future research would be useful are also highlighted.

  6. A policy-based multi-objective optimisation framework for residential distributed energy system design★

    Directory of Open Access Journals (Sweden)

    Wouters Carmen

    2017-01-01

    Full Text Available Distributed energy systems (DES are increasingly being introduced as solutions to alleviate conventional energy system challenges related to energy security, climate change and increasing demands. From a technological and economic perspective, distributed energy resources are already becoming viable. The question still remains as to how these technologies and practices can be “best” selected, sized and integrated within consumer areas. To aid decision-makers and enable widespread DES adoption, a strategic superstructure design framework is therefore still required that ensures balancing of multiple stakeholder interests and fits in with liberalised energy system objectives of competition, security of supply and sustainability. Such a design framework is presented in this work. An optimisation-based approach for the design of neighbourhood-based DES is developed that enables meeting their yearly electricity, heating and cooling needs by appropriately selecting, sizing and locating technologies and energy interactions. A pool of poly-generation and storage technologies is hereto considered combined with local energy sharing between participating prosumers through thermal pipeline design and microgrid operation, and, a bi-directional connection with the central distribution grid. A superstructure mixed-integer linear programming approach (MILP is proposed to trade off three minimisation objectives in the design process: total annualised cost, annual CO2 emissions and electrical system unavailability, aligned with the three central energy system objectives. The developed model is applied on a small South Australian neighbourhood. The approach enables identifying “knee-point” neighbourhood energy system designs through Pareto trade-offs between objectives and serves to inform decision-makers about the impact of policy objectives on DES development strategies.

  7. Residential Systems Based on Solid Oxide Fuel Cells for Scandinavian Climate

    DEFF Research Database (Denmark)

    Rokni, Masoud; Vialetto, Giulio

    2015-01-01

    Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence and to increase the use of renewable energies. In the last several years, new technologies have been developed, and some...... of them received subsidies to increase installation and reduce cost. This article presents an innovative cogeneration system based on a solid oxide fuel cell (SOFC) system and heat pump for household applications with a focus on primary energy and economic savings using electric equivalent load parameter...

  8. Design, construction, and testing of a residential solar heating and cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.S.; Loef, G.O.G.

    1976-06-01

    The NSF/CSU Solar House I solar heating and cooling system became operational on 1 July 1974. During the first months of operation the emphasis was placed on adjustment, ''tuning,'' and fault correction in the solar collection and the solar/fuel/cooling subsystems. Following this initial check out period, analysis and testing of the system utilizing a full year of data were accomplished. This report discusses the results of this analysis of the full year of operation. (WDM)

  9. The end of the line: The relationship between New York City's subway system and residential class structure

    Science.gov (United States)

    Rhindress, Mindy

    Public money is necessary to build and maintain this country's vast network of mass transit systems and highways. Thus you would expect class equity in choices of infrastructure location, types of projects and pricing. However, the influence of commercial interests appears to create a contradictory effect, and may negatively influence the settlement patterns where transit serves. New York City and its subway system offered the perfect case study by which to examine the before and after effects of mass transit introduction given the enormous size of the transit system and the grand development of New York City that appeared to occur simultaneous to subway inauguration. The main objective of this study was to determine the relationship between the growth of the New York City subway system and the establishment of class structure in residential patterns. Regional census data covering the first 16-year period of the subway's development was examined along with geographic statistics on subway line expansion and station openings. GIS (Geographic Information Systems) maps were used to illustrate the development of living spaces as a function of subway introduction into communities, and several Indices were computed to demonstrate the population growth and class disparity. The results revealed that the early years of transit development were entrepreneurial efforts coordinated by business interests. This led to transit first providing significant benefits mostly to the middle and upper classes, giving them a reasonable means by which to escape horrible tenement living conditions while turning a profit at the same time. Thus new settlements were stratified by class almost immediately after introduction. The cycle continued until years later when the automobile was introduced and the once expensive and luxurious, but now more reasonably priced and just functional, public transit system finally befit the population much lower on the socioeconomic scale. Class divisions still

  10. An Overview of Low Voltage DC Distribution Systems for Residential Applications

    DEFF Research Database (Denmark)

    Diaz, Enrique Rodriguez; Firoozabadi, Mehdi Savaghebi; Quintero, Juan Carlos Vasquez

    2015-01-01

    The concept of a microgrid has drawn the interest of research community in recent years. The most interesting aspects are the integration of renewable energy sources and energy storage systems at the consumption level, aiming to increase power quality, reliability and efficiency. On top of this, ...

  11. Steam System Balancing and Tuning for Multifamily Residential Buildings in Chicagoland - Second Year of Data Collection

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.; Ludwig, P.; Brand, L.

    2013-08-01

    Steam heated buildings often suffer from uneven heating as a result of poor control of the amount of steam entering each radiator. In order to satisfy the heating load to the coldest units, other units are overheated. As a result, some tenants complain of being too hot and open their windows in the middle of winter, while others complain of being too cold and are compelled to use supplemental heat sources. Building on previous research, CNT Energy identified 10 test buildings in Chicago and conducted a study to identify best practices for the methodology, typical costs, and energy savings associated with steam system balancing. A package of common steam balancing measures was assembled and data were collected on the buildings before and after these retrofits were installed to investigate the process, challenges, and the cost effectiveness of improving steam systems through improved venting and control systems. The test buildings that received venting upgrades and new control systems showed 10.2% savings on their natural gas heating load, with a simple payback of 5.1 years. The methodologies for and findings from this study are presented in detail in this report. This report has been updated from a version published in August 2012 to include natural gas usage information from the 2012 heating season and updated natural gas savings calculations.

  12. Development of residential solar air conditioning system for electricity power peak cut 3

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Gwon Jong [Korea Inst. of Energy and Resources, Daeduk (Korea, Republic of)

    1995-12-31

    In this research, the converter rectifier unit of the inverter air conditioner is substituted into the bidirectional PWM converter. The DC/DC power converter is established on the DC link between the photovoltaic array and the inverter air conditioner, and the photovoltaic air conditioning system which can be parallel driven which utility is developed. (author). 35 ref., 112 figs.

  13. A New Cogeneration Residential System Based on Solid Oxide Fuel Cells for a Northern European Climate

    DEFF Research Database (Denmark)

    Vialetto, Giulio; Rokni, Masoud

    2015-01-01

    Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence and to increase the use of renewable energies. In the last several years, new technologies have been developed, and some...... of them received subsidies to increase installation and reduce cost. This article presents an innovative cogeneration system based on a solid oxide fuel cell (SOFC) system and heat pump for household applications with a focus on primary energy and economic savings using electric equivalent load parameter...... are performed under different strategies at a resort located in a northern European climate (Denmark) to cover electricity, space heating and domestic hot water (DHW) demands. The results of these simulations are analyzed with thermodynamic and techno-economic benchmarks, considering different economic...

  14. Test Protocol for Room-to-Room Distribution of Outside Air by Residential Ventilation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Barley, C. D.; Anderson, R.; Hendron, B.; Hancock, E.

    2007-12-01

    This test and analysis protocol has been developed as a practical approach for measuring outside air distribution in homes. It has been used successfully in field tests and has led to significant insights on ventilation design issues. Performance advantages of more sophisticated ventilation systems over simpler, less-costly designs have been verified, and specific problems, such as airflow short-circuiting, have been identified.

  15. The Simulation Study of a Restructured Residential Low-Voltage Distribution System Microgrid

    Directory of Open Access Journals (Sweden)

    L. Ramesh

    2016-12-01

    Full Text Available A primary and necessary focus in creating a greener environment is the conversion of existing power-generation sources to renewable power sources in the near future. Another important focus is to develop sustainable household power generation to a low-voltage electricity grid with a power purchase and selling facility. To help with achieving the above vision, the objective of this work is to critically analyze the existing low-voltage distribution system and make suggestions for restructuring it to the low-voltage interconnected microgrid (MG. The test was carried out in the Tamil Nadu Electricity Board (TNEB 100kVA transformer feeder which was connected to supply around 100 houses with electricity. The performance analysis of the proposed system was examined through different case studies, represented as a normal operating condition of the existing distribution system and a reconstructed and interconnected MG to the TNEB grid. The project was designed and analyzed using PSCAD software. The results discussed in the project are helpful in examining the effects of multiple distributed energy resources on distributed generation. In future, knowledge of these effects may be helpful for rural area electrification.

  16. Exploring the market for third-party-owned residential photovoltaic systems: insights from lease and power-purchase agreement contract structures and costs in California

    Science.gov (United States)

    Davidson, Carolyn; Steinberg, Daniel; Margolis, Robert

    2015-02-01

    Over the past several years, third-party-ownership (TPO) structures for residential photovoltaic (PV) systems have become the predominant ownership model in the US residential market. Under a TPO contract, the PV system host typically makes payments to the third-party owner of the system. Anecdotal evidence suggests that the total TPO contract payments made by the customer can differ significantly from payments in which the system host directly purchases the system. Furthermore, payments can vary depending on TPO contract structure. To date, a paucity of data on TPO contracts has precluded studies evaluating trends in TPO contract cost. This study relies on a sample of 1113 contracts for residential PV systems installed in 2010-2012 under the California Solar Initiative to evaluate how the timing of payments under a TPO contract impacts the ultimate cost of the system to the customer. Furthermore, we evaluate how the total cost of TPO systems to customers has changed through time, and the degree to which contract costs have tracked trends in the installed costs of a PV system. We find that the structure of the contract and the timing of the payments have financial implications for the customer: (1) power-purchase contracts, on average, cost more than leases, (2) no-money-down contracts are more costly than prepaid contracts, assuming a customer’s discount rate is lower than 17% and (3) contracts that include escalator clauses cost more, for both power-purchase agreements and leases, at most plausible discount rates. In addition, all contract costs exhibit a wide range, and do not parallel trends in installed costs over time.

  17. Exploring the market for third-party-owned residential photovoltaic systems: insights from lease and power-purchase agreement contract structures and costs in California

    International Nuclear Information System (INIS)

    Davidson, Carolyn; Steinberg, Daniel; Margolis, Robert

    2015-01-01

    Over the past several years, third-party-ownership (TPO) structures for residential photovoltaic (PV) systems have become the predominant ownership model in the US residential market. Under a TPO contract, the PV system host typically makes payments to the third-party owner of the system. Anecdotal evidence suggests that the total TPO contract payments made by the customer can differ significantly from payments in which the system host directly purchases the system. Furthermore, payments can vary depending on TPO contract structure. To date, a paucity of data on TPO contracts has precluded studies evaluating trends in TPO contract cost. This study relies on a sample of 1113 contracts for residential PV systems installed in 2010–2012 under the California Solar Initiative to evaluate how the timing of payments under a TPO contract impacts the ultimate cost of the system to the customer. Furthermore, we evaluate how the total cost of TPO systems to customers has changed through time, and the degree to which contract costs have tracked trends in the installed costs of a PV system. We find that the structure of the contract and the timing of the payments have financial implications for the customer: (1) power-purchase contracts, on average, cost more than leases, (2) no-money-down contracts are more costly than prepaid contracts, assuming a customer’s discount rate is lower than 17% and (3) contracts that include escalator clauses cost more, for both power-purchase agreements and leases, at most plausible discount rates. In addition, all contract costs exhibit a wide range, and do not parallel trends in installed costs over time. (letter)

  18. Optimizing Hydronic System Performance in Residential Applications, Ithaca, New York (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2013-11-01

    Condensing boiler technology has been around for many years and has proven to be a durable, reliable method of heating. Based on previous research efforts, however, it is apparent that these types of systems are not designed and installed to achieve maximum efficiency. For example, in order to protect their equipment in the field, manufacturers of low-mass condensing boilers typically recommend design strategies and components that ensure steady, high flow rates through the heat exchangers, such as primary-secondary piping, which ultimately result in decreased efficiency.

  19. Choosing The Right Technology - Optimized Design Of Renewable Supply Systems For Residential Houses

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2012-01-01

    the planning process. The methodology allows for specifying a level of Net Zero Energy Building (Net ZEB) performance to investigate cost reductions when allowing shares of fossil fuel consumption. The outcome is an optimal supply technology combination and optimal installed capacities in terms of the overall...... study several levels of Net ZEB performance have been investigated. The results show that supply systems based solely on renewable sources are still considerably more expensive than standard solutions and that substantial cost reductions can be reached by allowing a certain share of primary energy...

  20. Policy schemes, operational strategies and system integration of residential co-generation fuel cells

    DEFF Research Database (Denmark)

    Hansen, Lise-Lotte Pade; Schröder, Sascha Thorsten; Münster, Marie

    2013-01-01

    a heat-driven strategy, with and without time-differentiated tariffs, and an electricity price driven strategy for the operation as a virtual power plant. The corresponding support schemes identified cover feed-in tariffs, net metering and feed-in premiums. Additionally, the interplay of the micro......CHP units with the national energy systems has been analysed. Our main findings are that net metering would be an appropriate tool to support FC based microCHP in Denmark, whereas a price premium would be the preferable tool in France and Portugal. Copyright © 2012, Hydrogen Energy Publications, LLC...

  1. THE EVALUATION SYSTEM OF DESIGN SOLUTIONS FOR RESIDENTIAL PROPERTY ON THE PRE-INVESTMENT STAGE THROUGH NEURAL NETWORK TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    G. D. Kostsikava

    2016-01-01

    Full Text Available Ever since the Soviet Union design solutions were evaluated according to different criteria and indicators. At the present stage of evaluation systems of design solutions stands systemengineering doctrine is allocated. It is complemented by the theory of efficiency and financial sustainability investment project in view of the general market concept. Also great attention is paid to the virtual object modeling. It is urgent to include the behavior prediction of an investment construction project model at each stage of its life cycle. The high cost of all phases of this life cycle makes it necessary to calculate the feasibility of the investment. Very urgent to do it as accurately as possible and before we start of design works on the stage of the investment plan evaluation. Belarus has legislated pre-investment stage of construction project development. To evaluate the design solution at this stage is necessary to develop an investment justification, a project management plan and a business plan. They will evaluate and will compare several options for future objects by the complex. This requires not only time, but considerable financial costs. In order to optimize the process to develop an evaluation system design solutions based on existing projects. It allows the customer (investor choose design solutions to build the object without developing of pre-design documentations for several options. This system it is advisable to try out the example of apartment house building with the assistance of the national fund of project documentation and objects-analogues data bank. The developed evaluation system of design solutions for residential real estate objects in the pre-investment stage is supposed to use the theory of neural networks and neyroprogramming. This system bases on the input parameters projects. The hidden layer neurons are trained to choose suitable projects of apartment houses with their classification. The projects will be classified

  2. LOFT CIS analysis: 24'' H and V Duct outside penetration S-12A

    International Nuclear Information System (INIS)

    Pierce, A.T.

    1978-01-01

    The 24'' H and V Duct and related piping outside the LOFT containment and connected to containment penetration S-12A were analyzed to ASME Section III, Subsection NC (Class 2) criteria. The duct is part of the Containment Isolation System. The model considered the duct from the containment O.D. outward through the second isolation valve. Results of this analysis show that this section of the line will meet Class 2 requirements without modification

  3. LOFT CIS analysis: 24'' H and V Duct outside penetration S-12A

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, A.T.

    1978-08-18

    The 24'' H and V Duct and related piping outside the LOFT containment and connected to containment penetration S-12A were analyzed to ASME Section III, Subsection NC (Class 2) criteria. The duct is part of the Containment Isolation System. The model considered the duct from the containment O.D. outward through the second isolation valve. Results of this analysis show that this section of the line will meet Class 2 requirements without modification.

  4. An optimization methodology for the design of renewable energy systems for residential net zero energy buildings with on-site heat production

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2011-01-01

    The concept of net zero energy buildings (NZEB) has received increased attention throughout the last years. A well adapted and optimized design of the energy supply system is crucial for the performance of such buildings. This paper aims at developing a method for the optimal sizing of renewable...... energy supply systems for residential NZEB involving on-site production of heat and electricity in combination with electricity exchanged with the public grid. The model is based on linear programming and determines the optimal capacities for each relevant supply technology in terms of the overall system...

  5. Modeling of an Air Conditioning System with Geothermal Heat Pump for a Residential Building

    Directory of Open Access Journals (Sweden)

    Silvia Cocchi

    2013-01-01

    Full Text Available The need to address climate change caused by greenhouse gas emissions attaches great importance to research aimed at using renewable energy. Geothermal energy is an interesting alternative concerning the production of energy for air conditioning of buildings (heating and cooling, through the use of geothermal heat pumps. In this work a model has been developed in order to simulate an air conditioning system with geothermal heat pump. A ground source heat pump (GSHP uses the shallow ground as a source of heat, thus taking advantage of its seasonally moderate temperatures. GSHP must be coupled with geothermal exchangers. The model leads to design optimization of geothermal heat exchangers and to verify the operation of the geothermal plant.

  6. Levitated Duct Fan (LDF) Aircraft Auxiliary Generator

    Science.gov (United States)

    Eichenberg, Dennis J.; Emerson, Dawn C.; Gallo, Christopher A.; Thompson, William K.

    2011-01-01

    This generator concept includes a novel stator and rotor architecture made from composite material with blades attached to the outer rotating shell of a ducted fan drum rotor, a non-contact support system between the stator and rotor using magnetic fields to provide levitation, and an integrated electromagnetic generation system. The magnetic suspension between the rotor and the stator suspends and supports the rotor within the stator housing using permanent magnets attached to the outer circumference of the drum rotor and passive levitation coils in the stator shell. The magnets are arranged in a Halbach array configuration.

  7. Residential demolition and its impact on vacant lot hydrology: implications for the management of stormwater and sewer system overflows

    Science.gov (United States)

    Increased residential demolitions have made vacant lots a ubiquitous feature of the contemporary urban landscape. Vacant lots may provide ecosystem services such as stormwater runoff capture, but the extent of these functions will be regulated by soil hydrology. We evaluated soil...

  8. Environmental and Economic Impacts of Integrating Photovoltaic and Wind-Turbine Energy Systems in the Canadian Residential Sector

    Science.gov (United States)

    Syed, Ali M.; Fung, Alan S.; Ugursal, V. Ismet

    2008-01-01

    The Canadian residential sector contributes approximately 80 megatons of GHGs to the environment yearly. With the ratification of Kyoto Protocol, Canada has committed to reduce its 1990 GHG emission levels by at least 5% between 2008 and 2012. To meet this target, Canada must evaluate and exploit all feasible means to reduce fossil fuel energy…

  9. Strontium concentrations in corrosion products from residential drinking water distribution systems.

    Science.gov (United States)

    Gerke, Tammie L; Little, Brenda J; Luxton, Todd P; Scheckel, Kirk G; Maynard, J Barry

    2013-05-21

    The United States Environmental Protection Agency (US EPA) will require some U.S. drinking water distribution systems (DWDS) to monitor nonradioactive strontium (Sr(2+)) in drinking water in 2013. Iron corrosion products from four DWDS were examined to assess the potential for Sr(2+) binding and release. Average Sr(2+) concentrations in the outermost layer of the corrosion products ranged from 3 to 54 mg kg(-1) and the Sr(2+) drinking water concentrations were all ≤0.3 mg L(-1). Micro-X-ray adsorption near edge structure spectroscopy and linear combination fitting determined that Sr(2+) was principally associated with CaCO3. Sr(2+) was also detected as a surface complex associated with α-FeOOH. Iron particulates deposited on a filter inside a home had an average Sr(2+) concentration of 40.3 mg kg(-1) and the associated drinking water at a tap was 210 μg L(-1). The data suggest that elevated Sr(2+) concentrations may be associated with iron corrosion products that, if disturbed, could increase Sr(2+) concentrations above the 0.3 μg L(-1) US EPA reporting threshold. Disassociation of very small particulates could result in drinking water Sr(2+) concentrations that exceed the US EPA health reference limit (4.20 mg kg(-1) body weight).

  10. Analysis of Applications to Improve the Energy Savings in Residential Buildings Based on Systemic Quality Model

    Directory of Open Access Journals (Sweden)

    Antoni Fonseca i Casas

    2016-10-01

    Full Text Available Creating a definition of the features and the architecture of a new Energy Management Software (EMS is complex because different professionals will be involved in creating that definition and in using the tool. To simplify this definition and aid in the eventual selection of an existing EMS to fit a specific need, a set of metrics that considers the primary issues and drawbacks of the EMS is decisive. This study proposes a set of metrics to evaluate and compare EMS applications. Using these metrics will allow professionals to highlight the tendencies and detect the drawbacks of current EMS applications and to eventually develop new EMS applications based on the results of the analysis. This study presents a list of the applications to be examined and describes the primary issues to be considered in the development of a new application. This study follows the Systemic Quality Model (SQMO, which has been used as a starting point to develop new EMS, but can also be used to select an existing EMS that fits the goals of a company. Using this type of analysis, we were able to detect the primary features desired in an EMS software. These features are numerically scaled, allowing professionals to select the most appropriate EMS that fits for their purposes. This allows the development of EMS utilizing an iterative and user-centric approach. We can apply this methodology to guide the development of future EMS and to define the priorities that are desired in this type of software.

  11. Advanced phase change materials and systems for solar passive heating and cooling of residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Salyer, I.O.; Sircar, A.K.; Dantiki, S.

    1988-01-01

    During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.

  12. Residential Energy Performance Metrics

    Directory of Open Access Journals (Sweden)

    Christopher Wright

    2010-06-01

    Full Text Available Techniques for residential energy monitoring are an emerging field that is currently drawing significant attention. This paper is a description of the current efforts to monitor and compare the performance of three solar powered homes built at Missouri University of Science and Technology. The homes are outfitted with an array of sensors and a data logger system to measure and record electricity production, system energy use, internal home temperature and humidity, hot water production, and exterior ambient conditions the houses are experiencing. Data is being collected to measure the performance of the houses, compare to energy modeling programs, design and develop cost effective sensor systems for energy monitoring, and produce a cost effective home control system.

  13. Evaluation of a 'healthiness' rating system for food outlet types in Australian residential communities.

    Science.gov (United States)

    Moayyed, Hamid; Kelly, Bridget; Feng, Xiaoqi; Flood, Victoria

    2017-02-01

    To obtain expert consensus to develop and evaluate a rating system on the relative healthiness of Australian suburbs' food outlet types. Twenty-four food outlet types and 10 local suburbs were identified from previous mapping studies and based on a scan of suburbs across one large Australian geographical region. Initial food outlet 'scores' for relative healthiness were proposed based on available literature, classified into five categories, from 'most' to 'least' healthy. In round 1 of a modified Delphi survey, participants, Australian public health and nutrition experts, were given each outlet type's definition and the proposed scores and invited to modify the scores based on their perceived 'healthiness'. In round 2, participants were able to revise or adjust their scores. Median scores for food outlet types from both rounds highly correlated with the originally proposed scores (two-tailed Pearson's correlation coefficient 0.97 and 0.96, respectively, P = 0.01), and scores from round 1 highly correlated with those from round 2 (Pearson's coefficient 0.998, P = 0.01). Round 2 scores were used to calculate suburbs' overall food environment score, healthiness score, unhealthiness score and a ratio of unhealthiness to healthiness scores. There was strong positive correlation between suburbs' ratio of unhealthiness to healthiness scores and a previously recognised scoring ratio, Retail Food Environment Index (Spearman's rho 0.847, P outlet types found in Australian neighbourhoods. Proposed scores can be used to assess and compare healthiness of community food environments and to explore their associations with area characteristics, population's diet and health outcomes. © 2016 Dietitians Association of Australia.

  14. Advanced Strategy Guideline: Air Distribution Basics and Duct Design

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A.

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings. Principles discussed that will maximize occupant comfort include delivery of the proper amount of conditioned air for appropriate temperature mixing and uniformity without drafts, minimization of system noise, the impacts of pressure loss, efficient return air duct design, and supply air outlet placement, as well as duct layout, materials, and sizing.

  15. Optimum cystic duct closure: a comparative study using metallic clips, ENSEAL, and ENDOLOOP in swine.

    Science.gov (United States)

    McVay, Derek; Nelson, Daniel; Porta, Christopher R; Blair, Kelly; Martin, Matthew

    2013-05-01

    Metal clips are commonly used to secure the cystic duct during cholecystectomy, although use of an ENDOLOOP (Ethicon Endo-Surgery, Blue Ash, OH) is often touted as a more secure closure when postoperative endoscopic retrograde cholangiopancreatography (ERCP) is anticipated. The objective of this study was to test the strength of 3 different cystic duct closure methods in a model simulating postoperative biliary insufflation. The extrahepatic biliary system, including common bile duct, gallbladder, and cystic duct, was harvested en bloc from 22 swine postmortem. A cholecystectomy was performed and the cystic duct was secured using 1 of 3 randomly assigned methods: metallic clips (Ethicon Endo-Surgery), an ENDOLOOP (Ethicon Endo-Surgery), or an ENSEAL tissue sealing device (Ethicon Endo-Surgery). The common bile duct was cannulated with a pressure-monitoring system and insufflated with air. The burst pressures, location of rupture, and size of the common bile duct and cystic duct were recorded and compared. There were 7 pigs each in the ENDOLOOP and ENSEAL groups and 8 in the metallic clip group, with no statistical significance between cystic and common bile duct size. Mean burst pressure was 432 mm Hg for metallic clips, 371 mm Hg for the ENDOLOOP, and 238 mm Hg for the ENSEAL device (P = .02). Post hoc analysis revealed clips to be statistically superior when compared with the ENSEAL (P= .01). There was no statistical difference between the ENDOLOOP and metal clips or between the ENDOLOOP and the ENSEAL. All 3 closure methods successfully secured the cystic duct, with mean burst pressures exceeding 195 mm Hg. Metallic clips demonstrated the highest burst pressures and no cystic duct stump leaks. This study challenges the traditional dogma of additionally securing the cystic duct with an ENDOLOOP when postoperative biliary instrumentation is expected and also suggests that an adequately secure closure may be obtained with thermal sealing devices. Published by

  16. Thoracic duct lymphography by subcutaneous contrast agent ...

    African Journals Online (AJOL)

    A second lymphography revealed a collateral thoracic duct that was not detected during the first lymphography. The collateral duct was ligated and chylothorax was resolved after the second surgery. The lymphography applied in this study was minimally-invasive and easily provided images of the thoracic duct in a dog with ...

  17. LYMPHOVENOUS COMMUNICATIONS BETWEEN THE THORACIC DUCT AND THE AZYGOS VENOUS SYSTEM. Comunicaciones linfovenosas entre el conducto torácico y el sistema de la vena ácigos

    Directory of Open Access Journals (Sweden)

    Naief Dahran

    2016-03-01

    Full Text Available Las venas del tronco venoso de ácigos son altamente variables en lo que se refiere a orígenes, trayecto, afluentes y terminaciones. Las comunicaciones linfovenosas entre el conducto torácico y el sistema venoso de ácigos, fueron halladas en una disección de un cadáver embalsamado de 92 años de edad. El conducto linfático estaba dividido en dos pequeños vasos linfáticos los cuales, drenaban la vena hemiciácigos accesoria en los niveles de T9 y T8. Estas comunicaciones son clínicamente importantes debido a que pueden actuar como vías metastásicas desde la parte más inferior del cuerpo hasta los pulmones.  Veins of the azygos venous system are highly variable in terms of their origins, course, communications, tributaries and termination. Lymphovenous communic-ations between the thoracic duct and the azygos venous system were revealed during dissection of a 92-year-old female Thiel-embalmed cadaver. The thoracic duct branched into two small lymph vessels which drained into the accessory hemiazygos vein at the levels of T9 and T8. These communications are clinically important as they might act as metastatic pathways from the lower part of the body to the lungs

  18. Update of energy performance certificates in the residential sector and scenarios that consider the impact of automation, control and management systems: A case study of La Rioja

    International Nuclear Information System (INIS)

    López-González, Luis M.; López-Ochoa, Luis M.; Las-Heras-Casas, Jesús; García-Lozano, César

    2016-01-01

    Highlights: • A total of 9416 energy performance certificates in the residential sector were analyzed. • Approximately 40% of the energy performance certificates were incorrect. • The developed algorithms can be generalized for the remainder of Spain. • Introducing BACS and TBM systems can reduce building energy consumption by up to 26.36%. - Abstract: Energy performance certificates are considered to be tools for knowledge and energy planning in the residential sector. Although energy performance certificates describe primary energy consumption and the associated emissions of a home or building, they do not consider the influence of building automation control systems (BACS) or technical building management (TBM) systems on these parameters. The European Standard EN 15232 remedies this shortcoming and evaluates the savings in primary energy and the reduction of CO 2 emissions that can be achieved by these systems. This study investigates the energy performance certificates registered in the Autonomous Community of La Rioja and considers the policy changes in the Technical Building Code (Código Técnico de la Edificación) and, specifically, the Basic Document for Energy Saving (Documento Básico de Ahorro de Energía) (CTE-DB-HE). Due to this regulatory change, we corrected the certificates and outlined different scenarios based on the implementation of these systems in this study. These scenarios show the potential distribution of energy performance certificates and the improvements in the ratings obtained.

  19. Analysis of materials in ducts by Compton scattering

    International Nuclear Information System (INIS)

    Gouveia, M.A.G.; Lopes, R.T.; Jesus, E.F.O. de; Camerini, C.S.

    2000-01-01

    This work presents the use of the Compton Scattering Technique as essay, for materials characterization in petroleum ducts. The essay have been accomplished in laboratory ambit, so that the presented results should be analyzed so that the system can come to be used in the field. The inspection was performed using Compton Scattering techniques, with two detectors aligned, in an angle of 90 degrees with a source of Cs-137 with energy of 662 keV. The results demonstrated the good capacity of the system to detect materials deposited in petroleum ducts during petroleum transportation. (author)

  20. Prediction of fan assisted flow in a duct/pipe network

    International Nuclear Information System (INIS)

    Quraishi, M.S.

    1996-01-01

    The commonly used fan+duct model is usually based on a table generated by matching the fan and system characteristic curves with the applied pressure drop across the fan+duct/pipe network and using linear or polynomial interpolation for intermediate values. However, this empirical approach can only handle a single system configuration for each table. If this approach is replaced by an algebraic formulation a general and flexible model can be developed. The algebraic model will be able to account for failure of resistances in the duct/pipe system as well as the failure of duct/pipe at an intermediate location. This paper presents the development of an algebraic model for fan+duct/pipe systems. (author)

  1. Design of a Mobile Robot for Air Ducts Exploration

    Directory of Open Access Journals (Sweden)

    Moses A. Koledoye

    2017-10-01

    Full Text Available This work presents the solutions adopted for the design and the implementation of an autonomous wheeled robot developed for the exploration and mapping of air ventilation ducts. The hardware is based on commercial off-the-shelf devices, including sensors, motors, processing devices and interfaces. The mechanical chassis was designed from scratch to meet a trade-off between small size and available volume to host the components. The software stack is based on the Robot Operating System (ROS. Special attention was dedicated to the design of the mobility strategy, which must take into account some constraints and issues that are specific to the considered application, such as the relatively small size of ducts, the need to detect and avoid possible holes on the floor of the duct and other unusual obstacles and the unavailability of external reference frameworks for localization. The main contribution of this paper lies in the design, implementation and experimentation of the overall system.

  2. Zebrafish sox9b is crucial for hepatopancreatic duct development and pancreatic endocrine cell regeneration.

    Science.gov (United States)

    Manfroid, Isabelle; Ghaye, Aurélie; Naye, François; Detry, Nathalie; Palm, Sarah; Pan, Luyuan; Ma, Taylur P; Huang, Wei; Rovira, Meritxell; Martial, Joseph A; Parsons, Michael J; Moens, Cecilia B; Voz, Marianne L; Peers, Bernard

    2012-06-15

    Recent zebrafish studies have shown that the late appearing pancreatic endocrine cells are derived from pancreatic ducts but the regulatory factors involved are still largely unknown. Here, we show that the zebrafish sox9b gene is expressed in pancreatic ducts where it labels the pancreatic Notch-responsive cells previously shown to be progenitors. Inactivation of sox9b disturbs duct formation and impairs regeneration of beta cells from these ducts in larvae. sox9b expression in the midtrunk endoderm appears at the junction of the hepatic and ventral pancreatic buds and, by the end of embryogenesis, labels the hepatopancreatic ductal system as well as the intrapancreatic and intrahepatic ducts. Ductal morphogenesis and differentiation are specifically disrupted in sox9b mutants, with the dysmorphic hepatopancreatic ducts containing misdifferentiated hepatocyte-like and pancreatic-like cells. We also show that maintenance of sox9b expression in the extrapancreatic and intrapancreatic ducts requires FGF and Notch activity, respectively, both pathways known to prevent excessive endocrine differentiation in these ducts. Furthermore, beta cell recovery after specific ablation is severely compromised in sox9b mutant larvae. Our data position sox9b as a key player in the generation of secondary endocrine cells deriving from pancreatic ducts in zebrafish. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. A comparison of fuel savings in the residential and commercial sectors generated by the installation of solar heating and cooling systems under three tax credit scenarios

    Science.gov (United States)

    Moden, R.

    An analysis of expected energy savings between 1977 and 1980 under three different solar tax credit scenarios is presented. The results were obtained through the solar heating and cooling of buildings (SHACOB) commercialization model. This simulation provides projected savings of conventional fuels through the installation of solar heating and cooling systems on buildings in the residential and commercial sectors. The three scenarios analyzed considered the tax credits contained in the Windfall Profits Tax of April 1980, the National Tax Act of November 1978, and a case where no tax credit is in effect.

  4. Plasma transport in magnetic duct filter

    International Nuclear Information System (INIS)

    Zhang Tao; Chu, Paul K; Fu, Ricky K Y; Brown, Ian G

    2002-01-01

    A cathodic arc plasma source equipped with a curved magnetic duct to filter macro-particles was used to study plasma transport through the duct. The optimal duct bias, at which the magnetic duct produces the maximum plasma output, for titanium cathodic arc plasma at 50, 100 and 150 A arc current was determined and the parametric effects of the arc current and guiding magnetic field on the optimal duct bias were investigated. The optimal bias decreased as the guiding magnetic field increased from 100 to 400 G and was almost independent of the guiding magnetic field when it was between 400 and 600 G, the upper limit for our equipment. The optimal duct bias at 400 G guiding magnetic field decreased with increasing arc current. Our results indicate that the optimal duct bias is related not only to the structure of the plasma source, but is also influenced by many other factors including cathode material and other plasma properties

  5. The Quest for Luschka's Duct : An Eponym Leading a Life of Its Own?

    NARCIS (Netherlands)

    Boonstra, Elizabeth A.; Lorenz, Karlotta; Porte, Robert J.

    2014-01-01

    Background: The German anatomist Hubert von Luschka gave name to several structures in the human body. One of great discussion is the duct of Luschka, part of the biliary system. There are different descriptions of the duct of Luschka. This might lead to confusion in the debate and as to what

  6. Modal analysis of an ECC duct for APR+ reactor barrel

    International Nuclear Information System (INIS)

    Kang, H.S.; Lee, K.H.; Kwon, T.S.

    2011-01-01

    Advanced Power Reactor Plus (APR+) provides four Direct Vessel Injection (DVI) ducts on the reactor barrel to enhance the performance of Emergency Core Cooling System (ECCS). Several studies on safety analysis have verified the excellent performance of the DVI duct. In this study, from the viewpoint of mechanical integrity, modal analyses of two full-scaled DVI ducts have been presented; both numerical analysis and modal tests have been performed in air and water. It was found that the numerical simulation and modal test coincide with each other. The DVI duct is a thin shell of 5 mm thickness, so that harmonic responses to RCP blade passing frequencies should be checked. The dominant passing frequencies are known to be 20, 40, 60, 120 and 240 Hz. In addition, an interesting thing in this study is that added mass effect by coolant seems to be so significant that the natural frequency of the ducts under water could be considerably low as compared with those in air; the natural frequency under water is 60 % lower than that in air. (author)

  7. Abnormalities of intrahepatic bile ducts in extrahepatic biliary atresia.

    Science.gov (United States)

    Raweily, E A; Gibson, A A; Burt, A D

    1990-12-01

    The infantile cholangiopathies are a group of conditions associated with neonatal jaundice, which include extrahepatic biliary atresia, paucity of intra-hepatic bile ducts and disorders associated with persistence of fetal biliary structures, the so-called ductal plate malformations. Although previously regarded as distinct entities, it has recently been suggested that they may represent parts of a disease spectrum in which the principal process is one of bile duct destruction, the morphological manifestations in individual cases being influenced by the stage of intra-uterine development at which such injury occurs and by the site within the biliary system at which there is maximum damage. To further examine this concept, we have studied liver biopsy specimens from 37 neonates with extrahepatic biliary atresia, with particular reference to abnormalities of the intrahepatic bile ducts. Paucity of intrahepatic ducts, defined as a bile duct: portal tract ratio of less than 0.9, was identified in six cases (16.2%). In eight cases (21.6%) we found concentric tubular ductal structures similar to those observed in ductal plate malformations. In one case, both abnormalities could be demonstrated. Our findings support the concept that there is overlap between the various types of infantile cholangiopathy.

  8. Mammary Duct Ectasia

    Science.gov (United States)

    ... Reactive and inflammatory conditions of the breast. In: Breast Pathology. Philadelphia, Pa.: Saunders Elsevier; 2012. https://www.clinicalkey.com. Accessed Feb. 5, 2015. Diagnosis of breast disease. Bloomington, Minn.: Institute for Clinical Systems Improvement ( ...

  9. Modeling and optimization of a heat-pump-assisted high temperature proton exchange membrane fuel cell micro-combined-heat-and-power system for residential applications

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Kær, Søren Knudsen; Nielsen, Mads Pagh

    2015-01-01

    -CHP system assumes heat-led operation, to avoid dumping of heat and the use of complicated thermal energy storage. The overall system is grid-interconnected to allow importing and exporting of electricity as necessary. In this study emphasis is given on the operational characterization of the system......In this study a micro-combined-heat-and-power (micro-CHP) system is coupled to a vapor-compression heat pump to fulfill the residential needs for heating (space heating and water heating) and electricity in detached single-family households in Denmark. Such a combination is assumed to be attractive...... for application, since both fuel cell technology and electric heat pumps are found to be two of the most efficient technologies for generation/conversion of useful energy. The micro-CHP system is fueled with natural gas and includes a fuel cell stack, a fuel processor and other auxiliary components. The micro...

  10. Building America Case Study: Effect of Ducted HPWH on Space Conditioning and Water Heating Energy Use - Central Florida Lab Home, Cocoa, Florida

    Energy Technology Data Exchange (ETDEWEB)

    C. Colon, E. Martin, and D. Parker

    2017-04-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWH's) on space conditioning and water heating energy use in residential applications. Two identical HPWH's, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  11. Transcatheter stenting of arterial duct in duct-dependent congenital heart disease

    Directory of Open Access Journals (Sweden)

    Đukić Milan

    2013-01-01

    Full Text Available Introduction. Critical congenital heart diseases (CHD are mostly duct-dependent and require stable systemic-pulmonary communication. In order to maintain patency of the ductus arteriosus (DA, the first line treatment is Prostaglandin E1 and the second step is the surgical creation of aortic-pulmonary shunt. To reduce surgical risk in neonates with the critical CHD, transcatheter stenting of DA can be performed in selected cases. Case Outline. A four-month old infant was diagnosed with the pulmonary artery atresia with ventricular septal defect (PAA/VSD. The left pulmonary artery was perfused from DA, and the right lung through three major aortopulmonary collaterals (MAPCAs. A coronary stent was placed in the long and critically stenotic DA, with final arterial duct diameter of 3.5 mm, and significantly increased blood supply to the left lung. After the procedure, the infant’s status was improved with regard to arterial oxygen saturation, feeding and weight gain. During the follow-up, one year later, aortography revealed in-stent stenosis. The left pulmonary artery, as well as the branches, was well-developed and the decision was made to proceed with further surgical correction. Conclusion. Stenting of DA can be an effective alternative to primary surgical correction in selected patients with duct-dependent CHD.

  12. Techno-economic feasibility of hybrid diesel/PV/wind/battery electricity generation systems for non-residential large electricity consumers under southern Iran climate conditions

    International Nuclear Information System (INIS)

    Baneshi, Mehdi; Hadianfard, Farhad

    2016-01-01

    Highlights: • A hybrid electricity generation system for a large electricity consumer was studied. • The PV and wind electricity potentials under given climate conditions were evaluated. • Technical, economical, and environmental issues of different systems were discussed. • The optimum configuration of components was obtained. • The impacts of governmental incentives on economic viability of systems were examined. - Abstract: This paper aims to study the techno-economical parameters of a hybrid diesel/PV/wind/battery power generation system for a non-residential large electricity consumer in the south of Iran. As a case study, the feasibility of running a hybrid system to meet a non-residential community’s load demand of 9911 kWh daily average and 725 kW peak load demand was investigated. HOMER Pro software was used to model the operation of the system and to identify the appropriate configuration of it based on comparative technical, economical, and environmental analysis. Both stand alone and grid connected systems were modeled. The impacts of annual load growth and governmental energy policies such as providing low interest loan to renewable energy projects, carbon tax, and modifying the grid electricity price on viability of the system were discussed. Results show that for off-grid systems the cost of electricity (COE) and the renewable fraction of 9.3–12.6 ₵/kWh and 0–43.9%, respectively, are achieved with photovoltaic (PV) panel, wind turbine, and battery sizes of 0–1000 kW, 0–600 kW, and 1300 kWh, respectively. For on grid systems without battery storage the range of COE and renewable fraction are 5.7–8.4 ₵/kWh and 0–53%, respectively, for the same sizes of PV panel and wind turbine.

  13. Combined heat and power generation with fuel cells in residential buildings in the future energy system; Kraft-Waerme-Kopplung mit Brennstoffzellen in Wohngebaeuden im zukuenftigen Energiesystem

    Energy Technology Data Exchange (ETDEWEB)

    Jungbluth, C.H.

    2007-04-27

    Combined heat and power generation (CHP) is regarded as one of the cornerstones of a future sustainable energy system. The application of this approach can be substantially extended by employing fuel cell technologies in small units for supplying heat to residential buildings. This could create an additional market for combined heat and power generation corresponding to approx. 25% of the final energy demand in Germany today. In parallel, the extensive application of distributed fuel cell systems in residential buildings would have substantial effects on energy infrastructures, primary energy demand, the energy mix and greenhouse gas emissions. It is the aim of the present study to quantify these effects via scenario modelling of energy demand and supply for Germany up to the year 2050. Two scenarios, reference and ecological commitment, are set up, and the application and operation of fuel cell plants in the future stock of residential buildings is simulated by a bottom-up approach. A model of the building stock was developed for this purpose, consisting of 213 types of reference buildings, as well as detailed simulation models of the plant operation modes. The aim was, furthermore, to identify economically and ecologically optimised plant designs and operation modes for fuel cells in residential buildings. Under the assumed conditions of the energy economy, economically optimised plant sizes for typical one- or two-family homes are in the range of a generating capacity of a few hundred watts of electrical power. Plant sizes of 2 to 4.7 kW{sub el} as discussed today are only economically feasible in multifamily dwellings. The abolition of the CHP bonus reduces profitability, especially for larger plants operated by contractors. In future, special strategies for power generation and supply can be an economically useful addition for the heat-oriented operation mode of fuel cells. On the basis of the assumed conditions of the energy economy, a technical potential for

  14. Optimal design and operation of a syngas-fuelled SOFC micro CHP system for residential applications in different climate zones in China

    DEFF Research Database (Denmark)

    Yang, Wenyuan; Zhao, Yingru; Liso, Vincenzo

    2014-01-01

    of the micro-CHP to cover the heat and electricity demand of a 70 m2 single-family apartment with an average number of occupants of 3 is evaluated. A detailed model of the micro-CHP unit coupled with a hot water storage tank and an auxiliary boiler is developed. System design trade-offs are discussed......Fuel cell based micro-CHP systems are expected to be one of the most promising technologies for implementation in the residential sector. Since the design and operation of such CHP systems are greatly dependent upon the seasonal atmospheric conditions, it is important to evaluate their performance...... under difference climate conditions to ensure that it is well matched with the local heat-to-power ratio. The aim of this study is to investigate the optimal design and operation of a syngas-fuelled SOFC micro-CHP system for small households located in five different climate zones in China. The ability...

  15. Evaluation of high performance evacuated tubular collectors in a residential heating and cooling system: Colorado State University Solar House I. Report for October 1, 1976--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Duff, W.S.; Conway, T.M.; Loef, G.O.G.; Meredith, D.B.; Pratt, R.B.

    1978-03-01

    CSU Solar House I is configured with a prototype Corning evacuated tubular collector and a new Arkla lithium bromide water chiller designed for solar operation. Data have been collected for this configuration since January 1977. Prior to that time and since mid-1974, Solar House I has operated with a flat-plate collector and a previous Arkla LiBr air conditioner modified to operate in the lower solar temperature ranges. Project objectives were to develop an operating and control system for the new configuration and to compare the performance of the new residential solar heating, cooling, and hot water system with performance of the previous system. Many problems were encountered in the evolution of the operating and control systems due to the different operating characteristics of evacuated tubular collectors, such as their rapid thermal response and the possibility of much higher temperatures as compared to a flat-plate collector.

  16. Simulation and performance analysis of 110 kWp grid-connected photovoltaic system for residential building in India: A comparative analysis of various PV technology

    Directory of Open Access Journals (Sweden)

    Akash Kumar Shukla

    2016-11-01

    Full Text Available System simulation is necessary to investigate the feasibility of Solar PV system at a given location. This study is done to evaluate the feasibility of grid connected rooftop solar photovoltaic system for a residential Hostel building at MANIT, Bhopal, India (Latitude: 23° 16′ N, Longitude: 77° 36′ E. The study focuses on the use of Solargis PV Planner software as a tool to analyze the performance a 110 kWp solar photovoltaic rooftop plant and also compares the performances of different PV technologies based on simulated energy yield and performance ratio. Solargis proves to easy, fast, accurate and reliable software tool for the simulation of solar PV system.

  17. Concept design studies on the ITER HNB Duct Liner

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, Sanjay, E-mail: sanjay.mistry@ccfe.ac.uk; Horvat, Andrej; Verhoeven, Roel; Xue, Yongkuan

    2013-10-15

    Highlights: •Engineering design of the ITER Heating Neutral Beam Duct Liner is outlined. •A vector-calculus method is used for calculations which evaluate directional heat flux on different scraper panel layouts. •A scraper panel layout with equal panel lengths and common thermal loading was achieved through these calculations. •The thermo-mechanical performance of a scraper panel satisfies ITER structural design criteria under a normal operation scenario. •Fast blow-out draining is used for complete emptying of a cooling arrangement. •Numerical simulations of the blow-out draining were carried out using RELAP5 and found to demonstrate satisfactory draining. -- Abstract: The Duct Liner for the International Thermonuclear Experimental Reactors (ITER) Heating Neutral Beam (HNB) system is a key component in the beam transport system. Power loading on the top and bottom beam scraping panels of the Duct Liner occurs primarily due to direct interception of the HNB and it is highest at the extreme steering angles of the beam. Furthermore, power loading due to direct interception is dependent on the size and orientation of the scraper panels with respect to the neutral beam axis. This paper outlines the design features of the proposed Duct Liner and describes the analysis performed to optimize the compatibility of the top and bottom scraper panels (also known as Duct Liner Modules) with a normal beam operation scenario. Thermo-mechanical analyses have been performed to validate the design of Duct Liner Modules incorporating deep-drilled cooling technology with a peak power density of 1.2 MW/m{sup 2} and incident power of 0.27 MW, and also to verify its conformity with ITER structural design criteria. Furthermore, numerical simulations of the transient draining procedure were performed by using a one-dimensional thermo-hydraulic code to demonstrate complete emptying of the proposed parallel-layout cooling circuit without any reliance on conventional gravity

  18. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Residential Building Heating, Ventilation, and Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Goetzler, William [Navigant Consulting, Inc., Burlington, MA (United States); Zogg, Robert [Navigant Consulting, Inc., Burlington, MA (United States); Young, Jim [Navigant Consulting, Inc., Burlington, MA (United States); Schmidt, Justin [Navigant Consulting, Inc., Burlington, MA (United States)

    2012-10-01

    This report is an assessment of 135 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. residential buildings to identify and provide analysis on 19 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, descriptions of technical maturity, descriptions of non-energy benefits, descriptions of current barriers for market adoption, and descriptions of the technology's applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

  19. Sizing the prime mover of a residential micro-combined cooling heating and power (CCHP) system by multi-criteria sizing method for different climates

    International Nuclear Information System (INIS)

    Ebrahimi, Masood; Keshavarz, Ali

    2013-01-01

    In the present study, a multi-criteria sizing function (MCSF) is proposed for designing the optimum size and operating strategy of the prime mover of a residential micro-combined cooling heating and power (CCHP) system. The CCHP prepares the electrical, thermal, cooling, and domestic hot water demands of the same building in five different climates in Iran. The MCSF integrates fuel energy saving ratio (FESR) and exergy efficiency as the thermodynamical parameters, net present value, internal rate of return and payback period for the economical criteria, and CO 2 , CO and NO x reduction for the environmental evaluations. Analytical hierarchy process is used to weigh each criterion with respect to others. The engine proposed by MCSF results in considerable fuel saving and pollution reduction and a payback period of about 6 years for the 5 climates. In addition, the best strategy according to the engine size is determined for every climate. - Highlights: ► A multi criteria sizing method (MCSM) is proposed. ► The MCSF includes thermodynamical, economical and environmental criteria. ► The components size of a residential CCHP system is calculated. ► The CCHP is designed for five different climates. ► The MCSM is easily programmable and user-friendly

  20. Modeling electric load and water consumption impacts from an integrated thermal energy and rainwater storage system for residential buildings in Texas

    International Nuclear Information System (INIS)

    Upshaw, Charles R.; Rhodes, Joshua D.; Webber, Michael E.

    2017-01-01

    Highlights: • Hydronic integrated rainwater thermal storage (ITHERST) system concept presented. • ITHERST system modeled to assess peak electric load shifting and water savings. • Case study shows 75% peak load reduction and 9% increase in energy consumption. • Potable rainwater collection could provide ∼50–90% of water used for case study. - Abstract: The United States’ built environment is a significant direct and indirect consumer of energy and water. In Texas, and other parts of the Southern and Western US, air conditioning loads, particularly from residential buildings, contribute significantly to the peak electricity load on the grid, straining transmission. In parallel, water resources in these regions are strained by growing populations and shrinking supplies. One potential method to address both of these issues is to develop integrated thermal energy and auxiliary water (e.g. rainwater, greywater, etc.) storage and management systems that reduce peak load and freshwater consumption. This analysis focuses on a proposed integrated thermal energy and rainwater storage (ITHERST) system that is incorporated into a residential air-source chiller/heat pump with hydronic distribution. This paper describes a step-wise hourly thermodynamic model of the thermal storage system to assess on-peak performance, and a daily volume-balance model of auxiliary water collection and consumption to assess water savings potential. While the model is generalized, this analysis uses a case study of a single family home in Austin, Texas to illustrate its capabilities. The results indicate this ITHERST system could reduce on-peak air conditioning electric power demand by over 75%, with increased overall electric energy consumption of approximately 7–9%, when optimally sized. Additionally, the modeled rainwater collection reduced municipal water consumption by approximately 53–89%, depending on the system size.

  1. Air quality and residential wood combustion - application of the model system SIMAIRrwc for some Swedish municipalities; Luftkvalitet och smaaskalig biobraensleeldning. Tillaempningar av SIMAIRved foer naagra kommuner

    Energy Technology Data Exchange (ETDEWEB)

    Omstedt, Gunnar; Andersson, Stefan; Johansson, Christer; Loefgren, Bengt-Erik

    2008-11-15

    SIMAIRrwc is a Web based evaluation tool for meeting the EU directive on air pollution limits in residential areas using wood combustion. The background is a four-year research program (2001-2004) called Biomass Combustion Health and Environment. Some conclusions from this program were that emissions from small scale wood combustion can influence human health mainly due to high emitting old wood stoves during cold weather conditions and that the air quality in such areas can improve significantly if old wood stoves were replaced by modern wood boilers attached to a storage tank or with a pellet boiler. SIMAIRrwc is based on the same principles as SIMAIRroad, which is a Web based evaluation tool for road traffic i.e. coupled model system using different models on local, urban and regional geographical scales, best available emission data, but at the same time presented in a very simplified way. In this project SIMAIRrwc has been applied in five different Swedish municipalities. The aim has been to apply and improve the model in cooperation with the municipalities. The conclusions from the project are: Small scale wood combustions in residential areas are local problems which sometimes include only a few houses and/or wood-burners. Air quality problems related to the EU directive are mainly due to particles. Combinations of residential areas with wood combustion and emissions from nearby dense traffic roads might give rise to bad air quality. Actions require knowledge about individual equipment which needs information from the local chimney sweeps. The best way to identify problem areas is to use model calculations. If model calculations indicate risks of exceeding air quality limits, then new calculations should be made with improved input data taking into account for example information of district heating or other installations that can effect the emissions. Before actions are taken it may also be useful to make measurements. The measurement site can then be

  2. Simulation study on reduction of peak power demand and energy consumption in residential houses with solar thermal and PV systems; Taiyo energy riyo jutaku no fuka heijunka oyobi energy sakugen koka no simulation ni yoru kento

    Energy Technology Data Exchange (ETDEWEB)

    Endo, T. [Yokohama City Office, Yokohama (Japan); Udagawa, M. [Kogakuin Univ., Tokyo (Japan). Faculty of Engineering

    1995-11-20

    In this study, taking the all factors involved in the energy consumption in residential houses as subjects, the effectiveness of the solar PV system and solar thermal utilizing system in residential houses has been studied by simulating a model residential house considering the improvement of the residual environment in the future. Therefore, a model residual house is assumed, 18 kinds of combinations of construction style, cooling and heating type and solar energy utilizing form are assumed and year round simulation is carried out. The conclusions obtained by the simulation are as follows. The energy consumption in residential houses may decrease greatly by using a solar hot water supplying system. If combined with a solar PV system, the energy consumption in one year is about 8.7 to 9.7 MWh. The combined use of a solar thermal utilizing system and a PV system is more effective to reduce the second-time energy in comparison with the PV system only. 36% of the space heating energy consumption may be decreased by using the solar space heating system, but the decrease effect of the energy consumption of the solar space heating system is smaller than the solar hot water supplying system. 12 refs., 26 figs., 3 tabs.

  3. Simulation and optimization study on a solar space heating system combined with a low temperature ASHP for single family rural residential houses in Beijing

    DEFF Research Database (Denmark)

    Deng, Jie; Tian, Zhiyong; Fan, Jianhua

    2016-01-01

    A pilot project of the solar water heating system combined with a low temperature air source heat pump (ASHP) unit was established in 2014 in a detached residential house in the rural region of Beijing, in order to investigate the system application prospect for single family houses via system op...... the integrated solar space heating for reducing carbon emission, it is suggested that the Beijing municipal government should offer some financial subsidy to compensate the equivalent solar heat price per kWh....... pilot household on the current electricity price level of 0.5 RMB/kWh, comparing with the reference condition of the fully ASHP space heating. It is further found that the equivalent solar heat price per kWh is too high under the current solar market cost price and collector technology. To put forward...

  4. Modeling radon transport in multistory residential buildings

    International Nuclear Information System (INIS)

    Persily, A.K.

    1993-01-01

    Radon concentrations have been studied extensively in single-family residential buildings, but relatively little work has been done in large buildings, including multistory residential buildings. The phenomena of radon transport in multistory residential buildings is made more complicated by the multizone nature of the airflow system and the numerous interzone airflow paths that must be characterized in such a system. This paper presents the results of a computer simulation of airflow and radon transport in a twelve-story residential building. Interzone airflow rates and radon concentrations were predicted using the multizone airflow and contaminant dispersal program (CON-TAM88). Limited simulations were conducted to study the influence of two different radon source terms, indoor-outdoor temperature difference and exterior wall leakage values on radon transport and radon concentration distributions

  5. Quadcopter thrust optimization with ducted-propeller

    Directory of Open Access Journals (Sweden)

    Kuantama Endrowednes

    2017-01-01

    Full Text Available In relation to quadcopter body frame model, propeller can be categorized into propeller with ducted and without ducted. This study present differences between those two using CFD (Computational Fluid Dynamics method. Both categories utilize two blade-propeller with diameter of 406 (mm. Propeller rotation generates acceleration per time unit on the volume of air. Based on the behavior of generated air velocity, ducted propeller can be modeled into three versions. The generated thrust and performance on each model were calculated to determine the best model. The use of ducted propeller increases the total weight of quadcopter and also total thrust. The influence of this modeling were analyzed in detail with variation of angular velocity propeller from 1000 (rpm to 9000 (rpm. Besides the distance between propeller tip and ducted barrier, the size of ducted is also an important part in thrust optimization and total weight minimization of quadcopter.

  6. Effect of Modifications to Induction System on Altitude Performance of V-1710-93 Engine III : Use of Parabolic Rotating Guide Vanes and NACA Designed Auxiliary-stage Inlet Elbow and Interstage Duct

    Science.gov (United States)

    Standahar, Ray M; Mccarty, James S

    1947-01-01

    Bench runs of a modified V-1710-93 engine equipped with a two-stage supercharger, interstage carburetor, aftercooler assembly, and backfire screens have been made at a simulated altitude of 29,000 feet to determine the effect of several induction-system modifications on the engine and supercharger performance. The standard guide vanes on the auxiliary- and engine-stage superchargers were replaced by rotating guide vanes with a parabolic blade profile. The auxiliary-stage inlet elbow and interstage duct were replaced with new units of NACA design. These modifications were made one at a time and data were obtained after each change to determine the effect of each modification. All runs were made at a constant engine speed of 3000 rpm at a simulated altitude of 29,000 feet and all changes in engine power were made by varying the speed of the auxiliary-stage supercharger.

  7. Planning for a Low Carbon Future? Comparing Heat Pumps and Cogeneration as the Energy System Options for a New Residential Area

    Directory of Open Access Journals (Sweden)

    Jukka Heinonen

    2015-08-01

    Full Text Available The purpose of this paper is to compare, from an urban planning perspective, the choice between combined heat and power (CHP and a ground-source heat pump (HP as the energy systems of a new residential area in the light of the uncertainty related to the assessments. There has been a strong push globally for CHP due to its climate mitigation potential compared to separate production, and consequently it is often prioritized in planning without questioning. However, the uncertainties in assessing the emissions from CHP and alternative options in a certain planning situation make it very difficult to give robust decision guidelines. In addition, even the order of magnitude of the climate impact of a certain plan is actually difficult to assess robustly. With a case study of the new residential development of Härmälänranta in Tampere, Finland, we show how strongly the uncertainties related to (1 utilizing average or marginal electricity as the reference; (2 assigning emissions intensities for the production; and (3 allocating the emissions from CHP to heat and electricity affect the results and lead to varying decision guidelines. We also depict how a rather rarely utilized method in assigning the emissions from CHP is the most robust for planning support.

  8. Antibiotic-resistant genes and antibiotic-resistant bacteria in the effluent of urban residential areas, hospitals, and a municipal wastewater treatment plant system.

    Science.gov (United States)

    Li, Jianan; Cheng, Weixiao; Xu, Like; Strong, P J; Chen, Hong

    2015-03-01

    In this study, we determined the abundance of 8 antibiotics (3 tetracyclines, 4 sulfonamides, and 1 trimethoprim), 12 antibiotic-resistant genes (10 tet, 2 sul), 4 antibiotic-resistant bacteria (tetracycline, sulfamethoxazole, and combined resistance), and class 1 integron integrase gene (intI1) in the effluent of residential areas, hospitals, and municipal wastewater treatment plant (WWTP) systems. The concentrations of total/individual targets (antibiotics, genes, and bacteria) varied remarkably among different samples, but the hospital samples generally had a lower abundance than the residential area samples. The WWTP demonstrated removal efficiencies of 50.8% tetracyclines, 66.8% sulfonamides, 0.5 logs to 2.5 logs tet genes, and less than 1 log of sul and intI1 genes, as well as 0.5 log to 1 log removal for target bacteria. Except for the total tetracycline concentration and the proportion of tetracycline-resistant bacteria (R (2) = 0.330, P antibiotics and the corresponding resistant bacteria (P > 0.05). In contrast, various relationships were identified between antibiotics and antibiotic resistance genes (P antibiotic-resistant bacteria (P < 0.01).

  9. Field Measurement and Evaluation of the Passive and Active Solar Heating Systems for Residential Building Based on the Qinghai-Tibetan Plateau Case

    Directory of Open Access Journals (Sweden)

    Zhijian Liu

    2017-10-01

    Full Text Available Passive and active solar heating systems have drawn much attention and are widely used in residence buildings in the Qinghai-Tibetan plateau due to its high radiation intensity. In fact, there is still lack of quantitative evaluation of the passive and active heating effect, especially for residential building in the Qinghai-Tibetan plateau areas. In this study, three kinds of heating strategies, including reference condition, passive solar heating condition and active solar heating condition, were tested in one demonstration residential building. The hourly air temperatures of each room under different conditions were obtained and analyzed. The results show the indoor air temperature in the living room and bedrooms (core zones was much higher than that of other rooms under both passive and active solar heating conditions. In addition, the heating effect with different strategies for core zones of the building was evaluated by the ratio of indoor and outdoor degree hour, which indicates that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment. The passive solar heating could undertake 49.8% degree hours for heating under an evaluation criterion of 14 °C and the active solar heating could undertake 75% degree hours for heating under evaluation criterion of 18 °C, which indicated that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment in this area. These findings could provide reference for the design and application of solar heating in similar climate areas.

  10. Thermal neutrons streaming in straight duct

    International Nuclear Information System (INIS)

    Jehouani, A.; Boulkheir, M.; Ichaoui, R.

    2000-01-01

    The neutron streaming in duct is due to two phenomena: a) direct propagation and b) reflection on duct wall. We have used the Monte Carlo method to evaluate the ratio of the reflected neutrons flux by the duct wall to the total flux at the exit of the duct for iron and aluminium. Ten neutrons energy groups are considered between 10 -5 eV and 10 eV. A Fortran program is developed to evaluate the neutron double differential albedo. It is shown that the two following approximations are largely justified: i) Three collisions in the duct wall are sufficient to attain the asymptotic limit of the multiscattered neutron double differential albedo ii) The points of entry and exit of the neutron in the duct wall may be considered the same for the multiscattered neutrons. For a punctual source at the mouth of the duct, we have determined the direct and the reflected part of the total thermal neutron flux at the exit of the duct for different lengths and different radius of the duct. For a punctual source, we have found that the major contribution to the total flux of neutrons at the exit is due to the neutron reflection by walls and the reflection contribution decreases when the neutron energy decreases. For a constant length of the duct, the reflected part decreases when the duct radius increases while for the disk shaped source we have found the opposite phenomena. The transmitted neutron flux distribution at the exit of the duct are determined for disk shaped source for different neutron energy and for different distance from the exit center. (author)

  11. A rare cause of nasolacrimal duct obstruction: Dentigerous cyst in the maxillary sinus

    Directory of Open Access Journals (Sweden)

    Ray Biswarup

    2009-01-01

    Full Text Available The most common abnormality of the lacrimal drainage system is congenital or acquired nasolacrimal duct obstruction. The causes of acquired nasolacrimal duct obstruction may be primary or secondary. The secondary acquired obstructions may result from infection, inflammation, neoplasm, trauma or mechanical causes. The maxillary sinus cysts usually obstruct the nasolacrimal duct mechanically. Dentigerous cysts are one of the main types of maxillary cysts. These cysts are benign odontogenic cysts which are associated with the crowns of unerupted teeth. The clinical documentations of mechanical nasolacrimal duct obstructions due to a dentigerous cyst in the maxillary sinus are very rare in literature. In this case report, we describe a dentigerous cyst with a supernumerary tooth in the maxillary sinus in an 11-year-old male child causing an obstruction to the nasolacrimal duct. The case was successfully managed surgically by Caldwell Luc approach.

  12. Resin duct characteristics associated with tree resistance to bark beetles across lodgepole and limber pines.

    Science.gov (United States)

    Ferrenberg, Scott; Kane, Jeffrey M; Mitton, Jeffry B

    2014-04-01

    Bark beetles have recently killed billions of trees, yet conifer defenses are formidable and some trees resist attack. A primary anti-insect defense of pines is oleoresin from a system of resin ducts throughout the tree. Resin defense traits are heritable, and evidence suggests that resin duct characteristics are associated with resistance to insects. However, comparisons of resin ducts in trees killed by bark beetles to trees that resisted attack are unavailable. We compared vertical resin duct characteristics (number, density, and size) and growth rates from trees that were "resistant" (survived mass attack) versus "susceptible" (killed by attack) to bark beetles in lodgepole (Pinus contorta) and limber (Pinus flexilis) pines. Resistant trees of both species had significantly more resin ducts in recent growth than susceptible trees. Discriminant analysis (DA) correctly categorized 84% of lodgepole and 92% of limber pines as susceptible/resistant based on combinations of resin duct and growth characteristics from recent 5- through 20-year growth intervals. DA models using measures from only the most recent 5 years of growth correctly categorized 72 and 81% of lodgepole and limber pines, respectively. Comparing resistant to susceptible trees independent of species identity led to the correct categorization of 82% of trees based on factors from 5- to 20-year intervals, and 73% of trees using only resin duct counts from the most recent 5 years. We conclude that resin duct characteristics can be used to assess tree resistance to bark beetles across pine species, and offer a metric for management to enhance pest resistance.

  13. Intraoperative cholangiographic findings of intrahepatic duct stones

    International Nuclear Information System (INIS)

    Kim, Mi Young; Suh, Chang Hae; Choi, Hye Ran; Ahn, Byeong Yeob; Chung, Woun Kyun; Lee, Yong

    1989-01-01

    Operative cholangiography is considered essential during biliary operation in order to minimise the chance of negative exploration and to demonstrate the anatomy and pathology of intra and extrahepatic biliary tree. Although many authors have evaluated and accepted various techniques for operative cholangiography, the image of operative cholangiography is affected mainly by intrahepatic duct stones and anatomic characteristic of biliary tree. In case of intrahepatic duct stones accurate evaluation of the operative cholangiographic findings is important for a plan of further treatment including interventional procedures. We reviewed 45 operative cholangiograms of 30 patients with intrahepatic duct stones from January,1986 to September, 1988, and analysed operative cholangiographic findings with a special attention to the correlation between cholangiographic findings and the location of intrahepatic duct stones. The results were as follows: 1. Common bile duct stones were found in 72%, and generalized cholangitis was combined in 43% of patient with intrahepatic duct stones. 2. Incomplete ductal filling of contrast media was the most frequent findings of left intrahepatic duct stones in operative cholangiograms with four different cholangiogram catheters. 3. Nonfilling and partial filling were the most frequent findings; nonfilling was prevalent in right anterior and left medial ducts, and partial filling was prevalent in left medial and left lateral ducts

  14. Laparoscopic common bile duct exploration versus endoscopic retrograde cholangiopancreatography for choledocholithiasis found at time of laparoscopic cholecystectomy: Analysis of a large integrated health care system database.

    Science.gov (United States)

    Al-Temimi, Mohammed H; Kim, Edwin G; Chandrasekaran, Bindupriya; Franz, Vanessa; Trujillo, Charles N; Mousa, Asrai; Tessier, Deron J; Johna, Samir D; Santos, David A

    2017-12-01

    We compared endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic common bile duct exploration (LCBDE) for managing choledocholithiasis found at time of cholecystectomy. One hundred and five LCBDE (2005-2015) were compared to 195 LC/ERCP (2014-2015) from the Southern California Kaiser Permanente database. LC/ERCP was more effective at clearing the CBD (98% vs. 88.6%, p = 0.01); but required more procedures per patient (mean ± standard deviation, 1.1 ± 0.4 vs. 2.0 ± 0.12, p  0.05). Four patients failed ERCP, while 12 patients failed LCBDE and had subsequent ERCP (10) or CBD exploration (2). All patients with RYGB had successful LCBDE. LC/ERCP is better than LCBDE in clearing CBD stones, but has similar morbidity and is an effective alternative for patients with RYGB. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Discontinuous finite element treatment of duct problems in transport calculations

    International Nuclear Information System (INIS)

    Mirza, A. M.; Qamar, S.

    1998-01-01

    A discontinuous finite element approach is presented to solve the even-parity Boltzmann transport equation for duct problems. Presence of ducts in a system results in the streaming of particles and hence requires the employment of higher order angular approximations to model the angular flux. Conventional schemes based on the use of continuous trial functions require the same order of angular approximations to be used everywhere in the system, resulting in wastage of computational resources. Numerical investigations for the test problems presented in this paper indicate that the discontinuous finite elements eliminate the above problems and leads to computationally efficient and economical methods. They are also found to be more suitable for treating the sharp changes in the angular flux at duct-observer interfaces. The new approach provides a single-pass alternate to extrapolation and interactive schemes which need multiple passes of the solution strategy to acquire convergence. The method has been tested with the help of two case studies, namely straight and dog-leg duct problems. All results have been verified against those obtained from Monte Carlo simulations and K/sup +/ continuous finite element method. (author)

  16. Design requirement on KALIMER blanket fuel assembly duct

    International Nuclear Information System (INIS)

    Hwang, Woan; Kang, H. Y.; Nam, C.; Kim, J. O.

    1998-03-01

    This document describes design requirements which are needed for designing the blanket fuel assembly duct of the KALIMER as design guidance. The blanket fuel assembly duct of the KALIMER consists of fuel rods, mounting rail, nosepiece, duct with pad, handling socket with pad. Blanket fuel rod consists of top end plug, bottom end plug with solid ferritic-martensitic steel rod and key way blanket fuel slug, cladding, and wire wrap. In the assembly, the rods are in a triangular pitch array, and the rod bundle is attached to the nosepiece with mounting rails. The bottom end of the assembly duct is formed by a long nosepiece which provides the lower restraint function and the paths for coolant inlet. This report contains functional requirements, performance and operational requirements, interfacing systems requirements, core restraint and interface requirements, design limits and strength requirements, system configuration and essential feature requirements, seismic requirements, structural requirements, environmental requirements, reliability and safety requirements, standard and codes, QA programs, and other requirements. (author). 20 refs., 4 figs

  17. Draft, development and optimization of a fuel cell system for residential power generation with steam reformer; Entwurf, Aufbau und Optimierung eines PEM-Brennstoffzellensystems zur Hausenergieversorgung mit Dampfreformer

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, H.

    2006-05-17

    The first development cycle of a residential power generation system is described. A steam reformer was chosen to produce hydrogen out of natural gas. After carbon monoxide purification with a preferential oxidation (PrOx) unit the hydrogen rich reformat gas is feed to the anode of the PEM-fuel cell, where due to the internal reaction with air oxygen form the cathode side water, heat and electricity is produced. Due to an incomplete conversion the anode off gas contains hydrogen and residual methane, which is feed to the burner of the steam reformer to reduce the needed amount of external fuel to heat the steam reformer. To develop the system the components are separately investigated and optimized in their construction or operation to meet the system requirements. After steady state and dynamic characterization of the components they were coupled one after another to build the system. To operate the system a system control was developed to operate and characterize this complex system. After characterization the system was analyzed for further optimization. During the development of the system inventions like a water cooled PrOx, an independent fuel cell controller or a burner for anodic off gas recirculation were made. The work gives a look into the interactions between the components and allows to understand the problems by coupling such components. (orig.)

  18. Laparoscopic common bile duct exploration.

    Science.gov (United States)

    Shuchleib, S; Chousleb, A; Mondragon, A; Torices, E; Licona, A; Cervantes, J

    1999-07-01

    Since the introduction of laparoscopic cholecystectomy, the management of common bile duct (CBD) stones has undergone significant change. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy is now routinely done in cases where the diagnosis of choledocholithiasis is suspected preoperatively, with clearance of the bile ducts before laparoscopic cholecystectomy. Intraoperative discovery of CBD stones by cholangiography represents a challenge to the surgeon, who must make a decision about when to perform laparoscopic CBD exploration, convert to open surgery, or send the patient for ERCP during the postoperative period. Because ERCP has a definite failure rate, laparoscopic CBD exploration can be a treatment option. Among 2500 laparoscopic cholecystectomies done by our group from January 1991 to June 1997, 50 patients (2%) underwent laparoscopic CBD exploration, 13 by the transcystic technique and 37 by choledocotomy, with a conversion rate of 8% and a hospital stay of 4.3 days. One patient died from complicated pancreatitis following ERCP and unsuccessful extraction of a CBD stone. We obtained our goal of a CBD free of stones in 92% of the cases. We conclude that laparoscopic CBD exploration is an effective method for treating choledocolithiasis that allows management of this pathology in one stage, although it requires advanced laparoscopic skills and adequate equipment.

  19. Origin, pattern, and mechanism of bile duct proliferation following biliary obstruction in the rat.

    Science.gov (United States)

    Slott, P A; Liu, M H; Tavoloni, N

    1990-08-01

    Proliferation of bile duct-like structures is a hepatic cellular reaction observed in most forms of human liver disease and in a variety of experimental conditions associated with liver injury. Yet the origin, means of initiation, and significance of this hyperplasia are unknown. To clarify these issues we induced bile duct proliferation in rats by ligating the common bile duct and studied (a) hepatic incorporation of [3H]thymidine by histoautoradiography, (b) hepatic morphometry, (c) biliary tree volume using [3H]taurocholate as a marker of biliary transit time, (d) immunohistochemical expression of cytokeratin no. 19, (e) the effect of indomethacin, and (f) the role of increased biliary pressure, in the absence of physiological and biochemical evidence of cholestasis, on [3H]thymidine incorporation by the bile-duct cells. The results have demonstrated that (a) the proliferating bile duct-like cells are products of the extant biliary epithelium and retain its characteristics; (b) bile duct cells divide irrespective of the size of the duct in which they are located and form a system with a lumen continuous with the preexisting one; (c) bile duct proliferation results mainly in elongation, not in circumferential enlargement or sprouting of side branches; (d) portal macrophage infiltration does not play a role in the hyperplastic reaction, and (e) increased biliary pressure is the initiating factor in bile duct cell division. Our results provide evidence that under the present conditions, ductular metaplasia of hepatocytes does not occur and there is no functioning stem cell for biliary epithelial growth segregated in any particular duct size or within the portal connective tissue.

  20. The anatomy of the thoracic duct at the level of the diaphragm: A cadaver study.

    Science.gov (United States)

    Defize, Ingmar L; Schurink, Bernadette; Weijs, Teus J; Roeling, Tom A P; Ruurda, Jelle P; van Hillegersberg, Richard; Bleys, Ronald L A W

    2018-03-03

    Injury and subsequent leakage of unrecognized thoracic duct tributaries during transthoracic esophagectomy may lead to chylothorax. Therefore, we hypothesized that thoracic duct anatomy at the diaphragm is more complex than currently recognized and aimed to provide a detailed description of the anatomy of the thoracic duct at the diaphragm. The thoracic duct and its tributaries were dissected in 7 (2 male and 5 female) embalmed human cadavers. The level of origin of the thoracic duct and the points where tributaries entered the thoracic duct were measured using landmarks easily identified during surgery: the aortic and esophageal hiatus and the arch of the azygos vein. The thoracic duct was formed in the thoracic cavity by the union of multiple abdominal tributaries in 6 cadavers. In 3 cadavers partially duplicated systems were present that communicated with interductal branches. The thoracic duct was formed by a median of 3 (IQR: 3-5) abdominal tributaries merging 8.3cm (IQR: 7.3-9.3cm) above the aortic hiatus, 1.8cm (IQR: -0.4 to 2.4cm) above the esophageal hiatus, and 12.3cm (IQR: 14.0 to -11.0cm) below the arch of the azygos vein. This study challenges the paradigm that abdominal lymphatics join in the abdomen to pass the diaphragm as a single thoracic duct. In this study, this occurred in 1/7 cadavers. Although small, the results of this series suggest that the formation of the thoracic duct above the diaphragm is more common than previously thought. This knowledge may be vital to prevent and treat post-operative chyle leakage. Copyright © 2018 Elsevier GmbH. All rights reserved.

  1. Hepaticocystic duct and a rare extra-hepatic "cruciate" arterial anastomosis: a case report

    Directory of Open Access Journals (Sweden)

    Abeysuriya Vasitha

    2008-02-01

    Full Text Available Abstract Introduction The variations in the morphological characteristics of the extra-hepatic biliary system are interesting. Case presentation During the dissection of cadavers to study the morphological characteristics of the extra-hepatic biliary system, a 46-year-old male cadaver was found to have drainage of the common hepatic duct drains directly into the gall bladder neck. The right and left hepatic ducts were not seen extra-hepatically. Further drainage of the bile away from the gallbladder and into the duodenum was provided by the cystic duct. Formation of the common bile duct by the union of the common hepatic duct and cystic duct was absent. Further more the right hepatic artery was found to be communicating with the left hepatic artery by a "bridging artery" after giving rise to the cystic artery. An accessory hepatic artery originated from the "bridging artery" forming a "cruciate" hepatic arterial anastomosis. Conclusion Combination of a Hepaticocystic duct and an aberrant variation in the extra-hepatic arterial system is extremely rare.

  2. Persistent Mullerian Duct Syndrome with Transverse Testicular ...

    African Journals Online (AJOL)

    The Mullerian duct regresses in male due to a glycoprotein secreted by the developing testes called. Mullerian inhibiting factor (MIF). Failure to regress may be due to lack of MIF or defective MIF receptor, resulting in various disorders of regression, and one such disorder is persistent Mullerian duct syndrome (PMDS).

  3. Prostatic Duct Adenocarcinoma with Endometrioid Features: Report ...

    African Journals Online (AJOL)

    mn

    4, 2009. 257. 257-258. Case Report. Prostatic Duct Adenocarcinoma with Endometrioid. Features: Report of a Rare Case and Brief Review of the Literature ... 3. adenocarcinoma of the prostate: A distinctive tumor of probable prostatic duct origin. Cancer. 1976;. May;37(5):2255-62. Cohen RJ, Wheeler TM, Bonkhoff H, ...

  4. Calcium influx pathways in rat pancreatic ducts

    DEFF Research Database (Denmark)

    Hug, M J; Pahl, C; Novak, I

    1996-01-01

    A number of agonists increase intracellular Ca2+ activity, [Ca2+]i, in pancreatic ducts, but the influx/efflux pathways and intracellular Ca2+ stores in this epithelium are unknown. The aim of the present study was to characterise the Ca2+ influx pathways, especially their pH sensitivity, in native...... pathways in pancreatic ducts cells....

  5. A hybrid society model for simulating residential electricity consumption

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Minjie [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); State Power Economic Research Institute, Beijing (China); Hu, Zhaoguang [State Power Economic Research Institute, Beijing (China); Wu, Junyong; Zhou, Yuhui [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China)

    2008-12-15

    In this paper, a hybrid social model of econometric model and social influence model is proposed for evaluating the influence of pricing policy and public education policy on residential habit of electricity using in power resources management. And, a hybrid society simulation platform based on the proposed model, called residential electricity consumption multi-agent systems (RECMAS), is designed for simulating residential electricity consumption by multi-agent system. RECMAS is composed of consumer agent, power supplier agent, and policy maker agent. It provides the policy makers with a useful tool to evaluate power price policies and public education campaigns in different scenarios. According to an influenced diffusion mechanism, RECMAS can simulate the residential electricity demand-supply chain and analyze impacts of the factors on residential electricity consumption. Finally, the proposed method is used to simulate urban residential electricity consumption in China. (author)

  6. A hybrid society model for simulating residential electricity consumption

    International Nuclear Information System (INIS)

    Xu, Minjie; Hu, Zhaoguang; Wu, Junyong; Zhou, Yuhui

    2008-01-01

    In this paper, a hybrid social model of econometric model and social influence model is proposed for evaluating the influence of pricing policy and public education policy on residential habit of electricity using in power resources management. And, a hybrid society simulation platform based on the proposed model, called residential electricity consumption multi-agent systems (RECMAS), is designed for simulating residential electricity consumption by multi-agent system. RECMAS is composed of consumer agent, power supplier agent, and policy maker agent. It provides the policy makers with a useful tool to evaluate power price policies and public education campaigns in different scenarios. According to an influenced diffusion mechanism, RECMAS can simulate the residential electricity demand-supply chain and analyze impacts of the factors on residential electricity consumption. Finally, the proposed method is used to simulate urban residential electricity consumption in China. (author)

  7. Optimal allocation and sizing of PV/Wind/Split-diesel/Battery hybrid energy system for minimizing life cycle cost, carbon emission and dump energy of remote residential building

    International Nuclear Information System (INIS)

    Ogunjuyigbe, A.S.O.; Ayodele, T.R.; Akinola, O.A.

    2016-01-01

    Highlights: • Genetic Algorithm is used for tri-objective design of hybrid energy system. • The objective is minimizing the Life Cycle Cost, CO 2 emissions and dump energy. • Small split diesel generators are used in place of big single diesel generator. • The split diesel generators are aggregable based on certain set of rules. • The proposed algorithm achieves the set objectives (LCC, CO 2 emission and dump). - Abstract: In this paper, a Genetic Algorithm (GA) is utilized to implement a tri-objective design of a grid independent PV/Wind/Split-diesel/Battery hybrid energy system for a typical residential building with the objective of minimizing the Life Cycle Cost (LCC), CO 2 emissions and dump energy. To achieve some of these objectives, small split Diesel generators are used in place of single big Diesel generator and are aggregable based on certain set of rules depending on available renewable energy resources and state of charge of the battery. The algorithm was utilized to study five scenarios (PV/Battery, Wind/Battery, Single big Diesel generator, aggregable 3-split Diesel generators, PV/Wind/Split-diesel/Battery) for a typical load profile of a residential house using typical wind and solar radiation data. The results obtained revealed that the PV/Wind/Split-diesel/Battery is the most attractive scenario (optimal) having LCC of $11,273, COE of 0.13 ($/kW h), net dump energy of 3 MW h, and net CO 2 emission of 13,273 kg. It offers 46%, 28%, 82% and 94% reduction in LCC, COE, CO 2 emission and dump energy respectively when compared to a single big Diesel generator scenario.

  8. Cholangiographic evaluation of bile duct carcinoma

    International Nuclear Information System (INIS)

    Nichols, D.A.; MacCarty, R.L.; Gaffey, T.A.

    1983-01-01

    Cholangiograms and clinical histories of 82 patients with biopsy-proved bile duct carcinoma were reviewed. The carcinomas were classified according to morphologic findings and clinical outcome. Ulcerative colitis and antecedent inflammatory disease of the biliary tree, particularly primary sclerosing cholangitis, seem to predispose to the development of bile duct carcinoma. Focal stenotic lesions were the most common morphologic type (62/82). Polypoid carcinomas and diffuse sclerosing carcinomas were less common and of about equal frequency. Prognosis was best for patients with polypoid carcinomas and worst for those with diffuse sclerosing carcinomas. In 69 cases (84%), the tumors involved the intrahepatic or proximal extrahepatic ducts, makin curative resection difficult or impossible. Patients with carcinomas limited to the more distal extrahepatic bile ducts had a longer average survival and a higher probability of surgical cure. Proper management of patients with bile duct carcinoma requires a complete and accurate cholangiographic evaluation of the morphology, location, and extent of the disease

  9. Salivary Duct Cyst: Histo-pathologic Correlation

    Directory of Open Access Journals (Sweden)

    Divya Vinayachandran

    2013-01-01

    Full Text Available Non-neoplastic cysts of the salivary glands are uncommon and represent 2-5% of all salivary gland lesions. They are mainly mucoceles or salivary duct cysts. Unlike a mucocele, which is surrounded by granulation tissue, the salivary duct cyst is lined by epithelium. Salivary duct cysts are more common in the oral minor salivary glands and rarely occur in the major salivary glands, show a marked predilection for the superficial lobe of the parotid, and represent 10% of all salivary gland cysts. Neoplastic differentiation of the lining of the salivary duct cyst has been reported. We report a case of a salivary duct cyst of the left parotid gland, with a review of radiographic and histopathologic features.

  10. An Integrated Heavy Fuel Piston Engine Ducted Fan Propulsion Unit for Personal Air Vehicles, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed PAVE propulsion system technology demonstration combines an innovative high-speed aero-diesel engine with a novel ducted fan assembly resulting in a low...

  11. An Integrated Heavy Fuel Piston Engine Ducted Fan Propulsion Unit for Personal Air Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed PAVE propulsion system technology demonstration combines an innovative high-speed aero-diesel engine with a novel ducted fan assembly resulting in a low...

  12. Guidelines for sampling, assessing, and restoring defective grout in prestressed concrete bridge post-tensioning ducts.

    Science.gov (United States)

    2013-10-01

    A significant proportion of the U.S. bridge inventory is based on bonded post-tensioned (PT) concrete construction. An : important aspect of maintaining corrosion protection of these PT systems is assuring that tendon ducts are properly grouted : wit...

  13. RESIDENTIAL MORTGAGE IN MODERN RUSSIA

    Directory of Open Access Journals (Sweden)

    Dementiev N. P.

    2015-03-01

    Full Text Available The article presents a comparative analysis of residential mortgages in Russia and the United States. The primary ways of mortgage refinancing are outlined. Predominance of the elements of two-level refinancing system of residential mortgage in Russia and the United States is shown. The activity of the Agency for Housing Mortgage Lending (AHML, the basic tool of the Russian government’s mortgage policy, is described in detail. In its objectives and functions the AHML is similar to the American mortgage agencies Ginnie Mae, Fannie Mae and Freddie Mac. Similarities were identified in the Russian and US residential mortgages in the pre-crisis period (high rates of mortgage growth, favourable economic conjuncture, low interest rates, large increase in house prices, speculative housing demand. During the mortgage crisis, the policies of the Russian and US governments and monetary authorities had also much in common (monetary policy easing, cheap central banks loans, extended facilities of mortgage refinancing on the part of state agencies, mortgage rescue scheme, social mortgage programs. But the scope of mortgage in Russia is enormously narrow as compared to the US mortgage. The most important reason for that - low incomes of the Russian population.

  14. The SNAQ(RC), an easy traffic light system as a first step in the recognition of undernutrition in residential care

    NARCIS (Netherlands)

    Kruizenga, H M; de Vet, H.C.W.; van Marissing, C.M.E.; Stassen, E.E.P.M.; Strijk, J.E.; van Bokhorst-de van der Schueren, M.A.E.; Horman, J.C.H.; Schols, J.M.G.A.; van Binsbergen, J.J.; Eliens, A; Knol, D L; Visser, M

    OBJECTIVE: Development and validation of a quick and easy screening tool for the early detection of undernourished residents in nursing homes and residential homes. DESIGN: Multi-center, cross sectional observational study. SETTING: Nursing homes and residential homes. PARTICIPANTS: The screening

  15. Field validation of a system for autodissemination of an entomopathogenic fungus, Isaria fumosorosea, to control the Asian citrus psyllid on residential citrus

    Science.gov (United States)

    The citrus industries of California and Texas share a pressing problem with the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae) and huanglongbing (HLB) spreading in residential citrus near commercial groves. Insecticidal treatment of residential trees for the psyllid is problem...

  16. Immunohistochemistry of the cytoskeleton in the excurrent ducts of the testis in birds of the Galloanserae monophyly.

    Science.gov (United States)

    Aire, T A; Ozegbe, P C

    2008-08-01

    The presence, location and degree of immunoexpression of various microfilament (MF) and intermediate filament (IF) systems (actin, cytokeratins, desmin, vimentin) were studied in the excurrent ducts of the testis in sexually mature and active galliform (Japanese quail, domestic fowl, turkey) and anseriform (duck) birds. These proteins were variably expressed between the epithelia and periductal tissue (periductal smooth muscle cell layer and interductal connective tissue) types and between species. Variable heterogeneous co-expression of filament systems was also found in the various duct epithelia and periductal tissue types: co-expression of filament systems was the rule rather than the exception. In the duck, neither vimentin nor cytokeratin was present in any of the tissues, whereas actin and desmin (absent in the rete testis) were co-expressed in the efferent ducts and epididymal duct unit (comprising the ductus conjugens, ductus epididymidis and ductus deferens). Actin, desmin and vimentin were generally co-expressed in the rete testis, efferent ducts and epididymal duct unit of the quail, domestic fowl and turkey, with vimentin being more strongly immunoreactive than actin and desmin in the epididymal duct unit, but more weakly immunoexpressed in the efferent ducts. Cytokeratin was present and co-expressed with actin, desmin and vimentin in the rete testis, efferent ducts and epididymal duct unit of the domestic fowl and turkey, but not in the quail and duck. The periductal smooth muscle cell layer and interductal tissue co-expressed actin, desmin and vimentin variably in all birds. Luminal spermatozoa of both the turkey and duck were immunonegative for all protein systems, whereas those of the quail and domestic fowl co-expressed actin, desmin and vimentin moderately or strongly. The tissues of the reproductive tract of male birds thus contain cytoskeletal protein systems that are variably but mostly co-expressed and whose contractile ability appears

  17. Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Magee, A.; Zoeller, W.

    2013-02-01

    The Consortium for Advanced Residential Buildings (CARB) monitored three houses in Jacksonville, FL, to investigate the effectiveness of encapsulated and encapsulated/buried ducts in reducing thermal losses and gains from ductwork in unconditioned attics. Burying ductwork beneath loose-fill insulation has been identified as an effective method of reducing thermal losses and gains from ductwork in dry climates, but it is not applicable in humid climates where condensation may occur on the outside of the duct jacket. By encapsulating the ductwork in closed cell polyurethane foam (ccSPF) before burial beneath loose-fill mineral fiber insulation, the condensation potential may be reduced while increasing the R-value of the ductwork.

  18. Technology Solutions Case Study: High-Performance Ducts in Hot-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    M. Hoeschele, A. German, E. Weitzel, R. Chitwood

    2015-08-01

    Ducts in conditioned space (DCS) represent a high priority measure for moving the next generation of new homes to the Zero Net Energy performance level. Various strategies exist for incorporating ducts within the conditioned thermal envelope. To support this activity, in 2013 the Pacific Gas & Electric Company initiated a project with Davis Energy Group (lead for the Building America team, Alliance for Residential Building Innovation) to solicit builder involvement in California to participate in field demonstrations of various DCS strategies. Builders were given incentives and design support in exchange for providing site access for construction observation, diagnostic testing, and builder survey feedback. Information from the project was designed to feed into California's 2016 Title 24 process, but also to serve as an initial mechanism to engage builders in more high performance construction strategies. This Building America project complemented information collected in the California project with BEopt simulations of DCS performance in hot/dry climate regions.

  19. Gallstone-Induced Perforation of the Common Bile Duct in Pregnancy

    Directory of Open Access Journals (Sweden)

    N. Dabbas

    2008-01-01

    Full Text Available Spontaneous perforation of the extrahepatic biliary system is a rare presentation of ductal stones. We report the case of a twenty-year-old woman presenting at term with biliary peritonitis caused by common bile duct (CBD perforation due to an impacted stone in the distal common bile duct. The patient had suffered a single herald episode of acute gallstone pancreatitis during the third trimester. The patient underwent an emergency laparotomy, bile duct exploration, and removal of the ductal stone. The postoperative course was uneventful.

  20. A Comparison of Optimal Operation of a Residential Fuel Cell Co-Generation System Using Clustered Demand Patterns Based on Kullback-Leibler Divergence

    Directory of Open Access Journals (Sweden)

    Takumi Hasizume

    2013-01-01

    Full Text Available When evaluating residential energy systems like co-generation systems, hot water and electricity demand profiles are critical. In this paper, the authors aim to extract basic time-series demand patterns from two kinds of measured demand (electricity and domestic hot water, and also aim to reveal effective demand patterns for primary energy saving. Time-series demand data are categorized with a hierarchical clustering method using a statistical pseudo-distance, which is represented by the generalized Kullback-Leibler divergence of two Gaussian mixture distributions. The classified demand patterns are built using hierarchical clustering and then a comparison is made between the optimal operation of a polymer electrolyte membrane fuel cell co-generation system and the operation of a reference system (a conventional combination of a condensing gas boiler and electricity purchased from the grid using the appropriately built demand profiles. Our results show that basic demand patterns are extracted by the proposed method, and the heat-to-power ratio of demand, the amount of daily demand, and demand patterns affect the primary energy saving of the co-generation system.

  1. The location and sizing of holes and obstructions in pipes and ducts

    Science.gov (United States)

    Oldham, David J.; de Salis, Max H. F.

    2002-11-01

    A change in the cross-sectional area of a duct or pipe due to the presence of an obstruction will modify the eigenfrequencies of that system. A technique is presented for determining the blockage area function of a pipe or duct based upon the concept of these eigenfrequency shifts but using resonance and antiresonance frequencies determined from a single measurement of sound pressure within a duct. The technique is shown to be capable of revealing the location and size of single and multiple obstructions to a high degree of accuracy. The technique has also been successfully applied to the detection, location and sizing of small holes in duct walls. The position of a hole in the duct wall is revealed as the beginning of an apparent gradual expansion in the reconstructed blockage area function emanating from an initial positive dc shift. Once the hole has been located, an impedance model of the duct incorporating the size and location of the hole and the measured wave number at the first-order duct resonance allows the determination of the area of the side hole from a simple quadratic equation.

  2. Sustainable solutions for cooling systems in residential buildings: case study in the Western Cape Province, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Foudzai, F.; M' Rithaa, M. [Cape Peninsula University of Technology, Cape Town (South Africa). Dept. of Industrial Design

    2010-07-01

    sustainable cooling in residential buildings of Western Cape, South Africa are discussed.

  3. Bile Duct Adenoma with Oncocytic Features

    Directory of Open Access Journals (Sweden)

    E. J. Johannesen

    2014-01-01

    Full Text Available Bile duct adenomas are benign bile duct proliferations usually encountered as an incidental finding. Oncocytic bile duct neoplasms are rare and the majority are malignant. A 61-year-old male with a diagnosis of colorectal adenocarcinoma was undergoing surgery when a small white nodule was discovered on the surface of the right lobe of his liver. This lesion was composed of cytologically bland cells arranged in tightly packed glands. These cells were immunopositive for cytokeratin 7, negative for Hep Par 1, contained mucin, and had a Ki67 proliferation index of 8%. The morphology, immunophenotype, presence of mucin, and normal appearing bile ducts, as well as the increased Ki67 proliferation rate, were consistent with a bile duct adenoma with oxyphilic (oncocytic change. Oncocytic tumors in the liver are rare; the first described in 1992. Only two bile duct adenomas with oncocytic change have been reported and neither of them had reported mucin production or the presence of normal appearing bile ducts within the lesion.

  4. Integrated Management of Residential Energy Resources

    Directory of Open Access Journals (Sweden)

    Antunes C. H.

    2012-10-01

    Full Text Available The increasing deployment of distributed generation systems based on renewables in the residential sector, the development of information and communication technologies and the expected evolution of traditional power systems towards smart grids are inducing changes in the passive role of end-users, namely with stimuli to change residential demand patterns. The residential user should be able to make decisions and efficiently manage his energy resources by taking advantages from his flexibility in load usage with the aim to minimize the electricity bill without depreciating the quality of energy services provided. The aim of this paper is characterizing electricity consumption in the residential sector and categorizing the different loads according to their typical usage, working cycles, technical constraints and possible degree of control. This categorization of end-use loads contributes to ascertain the availability of controllable loads to be managed as well as the different direct management actions that can be implemented. The ability to implement different management actions over diverse end-use load will increase the responsiveness of demand and potentially raises the willingness of end-users to accept such activities. The impacts on the aggregated national demand of large-scale dissemination of management systems that would help the end-user to make decisions regarding electricity consumption are predicted using a simulator that generates the aggregated residential sector electricity consumption under variable prices.

  5. [Salivary gland drainage into the thyroglossal duct].

    Science.gov (United States)

    Siem, G; Natvig, K; Kolbenstvedt, A; Lømo, J

    2001-01-20

    Failure in regression of the thyroglossal duct is one of the most common reasons for midline swellings in the neck. Several authors have described recurrent thyroglossal duct remnants with persisting draining sinuses. However, few have described accessory salivary glands that drain into the thyroglossal duct. In this article we report two such cases with midline salivary glands in the floor of the mouth. These two patients were subsequently successfully treated with radical tissue resection in the area between the hyoid bone and foramen cecum. Preoperative fistulography or sinography was useful to demonstrate the ductal ramification of the salivary glands, and use of methylene blue during surgery proved of significant value for the result.

  6. Sound power flux measurements in strongly exited ducts with flow

    Science.gov (United States)

    Holland, Keith R.; Davies, Peter O. A. L.; van der Walt, Danie C.

    2002-12-01

    This contribution describes new robust procedures for the measurement of sound power flux at appropriate axial positions along a duct with flow, using pairs of flush wall mounted microphones, or pressure transducers. The technology includes the application of selective averaging, order tracking, and optimized sampling rate methods to identify the small fraction of the total fluctuating wave energy that is being propagated along the flow path in a reverberent, or highly reactive duct system. Such measurements can also be used to quantify the local acoustic characteristics that govern the generation, transfer, and propagation of wave energy in the system. Illustrative examples include the determination of the acoustic characteristics of individual silencing elements installed in IC engine intakes and exhausts both on the flow bench and during controlled acceleration or run down on a test bed, where the wave component spectral levels approached 170 dB.

  7. Hepatic extraction of the aminoterminal propeptide of type III procollagen before and after bile duct ligation in pigs

    DEFF Research Database (Denmark)

    Bentsen, K D; Henriksen, Jens Henrik Sahl; Boesby, S

    1991-01-01

    before and during a 4-h period after ligation of the common bile duct was assessed from serum PIIINP concentrations in a systemic artery, the portal vein and a hepatic vein of seven healthy anaesthetized pigs. Seven sham-operated anaesthetized pigs served as controls. Ligation of the bile duct did...

  8. Transitional education for child laborers. A review of residential bridge camps for mainstreaming ex-child laborers into the formal education system.

    Science.gov (United States)

    Pantea, Maria-Carmen

    2012-01-01

    Residential bridge camps provide intensive education in residential settings with the aim of preparing hard-core child laborers to be integrated in mainstream schools. The author reviews the extent to which residential bridge camps are effective interventions for integrating former child laborers into the mainstream schools at age appropriate levels. The research was based on a thorough review of secondary data, with 786 abstracts being screened. Given the methodological limitations of the studies, the only reliable inferences the author can advance through this review are on the aspects that appear to be promising, but which require further research.

  9. Development of cost innovative BPs for a PEMFC stack for a 1 kW-class residential power generator (RPG) system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gil-yong; Jung, Min-kyung; Ryoo, Sung-nam; Ha, Sam-chul [Digital Appliance R and D, LG Electronics, Seoul 153-801 (Korea, Republic of); Park, Myung-seok [LG Solar Energy, Seoul 150-721 (Korea, Republic of); Kim, Sunhoe [Department of New Energy and Resource Engineering, Sangji University, Wonju, Gangwon 220-702 (Korea, Republic of)

    2010-12-15

    In order to satisfy the demands of customers, cost innovation of fuel cell systems is required for the commercialization of the fuel cell. Since the stack is one of the most expensive parts in a fuel cell system, cost reduction of stack is required for fuel cell commercialization. For this effort stainless steel 304 sheets were etched for the flow field and then coated for corrosion resistance. This enables the development of highly cost-effective bipolar plates (BPs) for a Proton Exchange Membrane Fuel Cell (PEMFC) stack of a 1 kW-class for Residential Power Generator (RPG). LG Electronics (LGE) developed a metal stack of 64 cells with the developed BPs and achieved a performance rating of 0.75 V/cell at 200 mA/cm{sup 2}. LGE also achieved a stack volume reduction of 20% compared to a stack of the same specifications consisting of graphite material BPs. The volume decrease can be represented as a cost reduction. LGE achieved the very low cost innovation to 1 USD per cell with cells developed from etched metal BPs. LGE also achieved 500 h of operation with LGE's RPG system; this test is still ongoing. The degradation rate of the stack was 27 {mu}V/hr. The end of life of the stack was estimated at approximately 17,000 h. (author)

  10. Traumatic resin ducts as indicators of bark beetle outbreaks

    Science.gov (United States)

    R. Justin DeRose; Matthew F. Bekker; James N. Long

    2017-01-01

    The formation of traumatic resin ducts (TRDs) represents an important induced defense in woody plants that enhances oleoresin production and flow in response to environmental perturbations. In some genera (Pinus), resin ducts are copious and conspicuous; however, in others (Picea), resin ducts are relatively rare. The occurrence and strength of resin ducts, in...

  11. Estimation of energy efficiency of residential buildings

    Directory of Open Access Journals (Sweden)

    Glushkov Sergey

    2017-01-01

    Full Text Available Increasing energy performance of the residential buildings by means of reducing heat consumption on the heating and ventilation is the last segment in the system of energy resources saving. The first segments in the energy saving process are heat producing and transportation over the main lines and outside distribution networks. In the period from 2006 to 2013. by means of the heat-supply schemes optimization and modernization of the heating systems. using expensive (200–300 $US per 1 m though hugely effective preliminary coated pipes. the economy reached 2.7 mln tons of fuel equivalent. Considering the multi-stage and multifactorial nature (electricity. heat and water supply of the residential sector energy saving. the reasonable estimate of the efficiency of the saving of residential buildings energy should be performed in tons of fuel equivalent per unit of time.

  12. Primary hepatocellular carcinoma in extrahepatic bile duct

    International Nuclear Information System (INIS)

    Jeong, Seok Tae; Ham, Soo Youn; Park, Cheol Min; Kim, Jung Hyuk; Cha, In Ho; Chung, Kyoo Byung; Suh, Woon Hyuck; Lee, Chang Hong

    1991-01-01

    Obstructive jaundice due to hepatocellular carcinoma in an extrahepatic bile duct, without a mass lesion in the liver parenchyma, is extremely rare. We experienced two cases of primary hepatocellular carcinoma arising from an extrahepatic bile duct: one in a 53-year-old man whose α -fetoprotein value was 800 ng/ml, and another in a 39-year-old woman, in whom the mass lesion was found to be attached to an extrahepatic bile duct. These tumors had a well-marginated sausage-like shape on CT and US, and the contrast media passed freely along their margins on both PTC and ERCP. Recurrences of these tumors were observed in the extrahepatic bile duct 6 and 2 months after surgery, respectively

  13. Unusually large sialolith of Wharton's duct

    Science.gov (United States)

    Iqbal, Ali; Gupta, Anup K.; Natu, Subodh S.; Gupta, Atul K.

    2012-01-01

    The formation of calcific concretions in the salivary duct or glands is a common disorder, especially in the submandibular glands. Most of the salivary calculi are small in size, in contrast to those that reach several centimeters, which are reported as megaliths or giant calculi in the literature. They may occur in any of the salivary gland ducts but are most common in Wharton's duct and the submandibular gland. This report presents clinical and radiographical sign of an unusually large sialolith. There was painless swelling on the floor of the edentulous mouth and patient was unaware of it. Radiographical examination revealed large irregular radio-opaque mass superimposed on right canine and premolar areas. This case report describes a patient presenting with an unusually large submandibular gland duct sialolith, the subsequent patient management, the aetiology, diagnosis and its treatment. PMID:23483770

  14. Reference values of MRI measurements of the common bile duct and pancreatic duct in children

    International Nuclear Information System (INIS)

    Gwal, Kriti; Bedoya, Maria A.; Patel, Neal; Darge, Kassa; Anupindi, Sudha A.; Rambhatla, Siri J.; Sreedharan, Ram R.

    2015-01-01

    Magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) is now an essential imaging modality for the evaluation of biliary and pancreatic pathology in children, but there are no data depicting the normal diameters of the common bile duct (CBD) and pancreatic duct. Recognition of abnormal duct size is important and the increasing use of MRCP necessitates normal MRI measurements. To present normal MRI measurements for the common bile duct and pancreatic duct in children. In this retrospective study we searched all children ages birth to 10 years in our MR urography (MRU) database from 2006 until 2013. We excluded children with a history of hepatobiliary or pancreatic surgery. We stratified 204 children into five age groups and retrospectively measured the CBD and the pancreatic duct on 2-D axial and 3-D coronal T2-weighted sequences. We performed statistical analysis, using logistic and linear regressions to detect the age association of the visibility and size of the duct measurements. We used non-parametric tests to detect gender and imaging plane differences. Our study included 204 children, 106 (52%) boys and 98 (48%) girls, with a median age of 33 months (range 0-119 months). The children were distributed into five age groups. The common bile duct was visible in all children in all age groups. The pancreatic duct was significantly less visible in the youngest children, group 1 (54/67, 80.5%; P = 0.003) than in the oldest children, group 5 (22/22, 100%). In group 2 the pancreatic duct was seen in 19/21 (90.4%), in group 3 52/55 (94.5%), and in group 4 39/39 (100%). All duct measurements increased with age (P < 0.001; r-value > 0.423), and the incremental differences between ages were significant. The measurement variations between the axial and coronal planes were statistically significant (P < 0.001); however these differences were fractions of millimeters. For example, in group 1 the mean coronal measurement of the CBD was 2.1 mm and the axial

  15. Reference values of MRI measurements of the common bile duct and pancreatic duct in children

    Energy Technology Data Exchange (ETDEWEB)

    Gwal, Kriti; Bedoya, Maria A.; Patel, Neal; Darge, Kassa; Anupindi, Sudha A. [University of Pennsylvania Perelman School of Medicine, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Rambhatla, Siri J. [Beth Israel Medical Center, Department of Pediatrics, Newark, NJ (United States); Sreedharan, Ram R. [University of Pennsylvania, Departments of Gastroenterology, Hepatology and Nutrition, The Children' s Hospital of Philadelphia, Perelman School of Medicine, Philadelphia, PA (United States)

    2015-08-15

    Magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) is now an essential imaging modality for the evaluation of biliary and pancreatic pathology in children, but there are no data depicting the normal diameters of the common bile duct (CBD) and pancreatic duct. Recognition of abnormal duct size is important and the increasing use of MRCP necessitates normal MRI measurements. To present normal MRI measurements for the common bile duct and pancreatic duct in children. In this retrospective study we searched all children ages birth to 10 years in our MR urography (MRU) database from 2006 until 2013. We excluded children with a history of hepatobiliary or pancreatic surgery. We stratified 204 children into five age groups and retrospectively measured the CBD and the pancreatic duct on 2-D axial and 3-D coronal T2-weighted sequences. We performed statistical analysis, using logistic and linear regressions to detect the age association of the visibility and size of the duct measurements. We used non-parametric tests to detect gender and imaging plane differences. Our study included 204 children, 106 (52%) boys and 98 (48%) girls, with a median age of 33 months (range 0-119 months). The children were distributed into five age groups. The common bile duct was visible in all children in all age groups. The pancreatic duct was significantly less visible in the youngest children, group 1 (54/67, 80.5%; P = 0.003) than in the oldest children, group 5 (22/22, 100%). In group 2 the pancreatic duct was seen in 19/21 (90.4%), in group 3 52/55 (94.5%), and in group 4 39/39 (100%). All duct measurements increased with age (P < 0.001; r-value > 0.423), and the incremental differences between ages were significant. The measurement variations between the axial and coronal planes were statistically significant (P < 0.001); however these differences were fractions of millimeters. For example, in group 1 the mean coronal measurement of the CBD was 2.1 mm and the axial

  16. The challenge: implement a management system integrated into QSMS in a work of ducts in the Amazon; O desafio: implementar um sistema de gestao integrada em QSMS (Qualidade, Seguranca, Meio Ambiente e Saude) em uma obra de dutos no Amazonas

    Energy Technology Data Exchange (ETDEWEB)

    Riquena, Renata M.P.T.; Araujo, Carlos Magno de A. [Ciclo Gestao Empresarial, Manaus, AM (Brazil)

    2008-07-01

    To manage changes in a scene with variable for uncontrollable times, was the challenge lived for a team of 8 professionals to implement a System of Integrated Management (SGI) in QSMS (Quality, Security, Environment and Health) in a workmanship of ducts in Amazon, next to a work force that arrived the 8,000 people more than, made use in a geographic extension of more than 600km, in remote localities, with communication difficulties. The state of Amazon possess a great cultural diversity and with this context, it was entered into an alliance experience and abilities of the most diverse parts of the country, added the much heat, rain, mud, stress, homesickness. The work if developed in the period of September of 2006 the December of 2007, and the results reached for the team, in this period, had demonstrated that SGI is possible, either where surrounding it will be, or which the transport of the organization, but will have a strong work in team, determination, flexibility, humility, allied the ability, the process could be of high value added for the enterprise. The numbers of 2007 had shown that the performance of an organization not only depends on resources, are material or financial, but mainly of the human resources. (author)

  17. Residential land values and their determinants in high density ...

    African Journals Online (AJOL)

    The study identified that residential segregation exists in Nigerian cities and the study area. Among urbanization and residential land use problems identified by the study are poor level of social and technical infrastructure, poor land and city management system capacity, paucity of planning laws, funding, poor institutional ...

  18. Designing and evaluating an electronic patient falls reporting system: perspectives for the implementation of health information technology in long-term residential care facilities.

    Science.gov (United States)

    Mei, Yi You; Marquard, Jenna; Jacelon, Cynthia; DeFeo, Audrey L

    2013-11-01

    Patient falls are the leading cause of unintentional injury and death among older adults. In 2000, falls resulted in over 10,300 elderly deaths, costing the United States approximately $179 million in incidence and medical costs. Furthermore, non-fatal injuries caused by falls cost the United States $19 billion annually. Health information technology (IT) applications, specifically electronic falls reporting systems, can aid quality improvement efforts to prevent patient falls. Yet, long-term residential care facilities (LTRCFs) often do not have the financial resources to implement health IT, and workers in these settings are often not ready to adopt such systems. Additionally, most health IT evaluations are conducted in large acute-care settings, so LTRCF administrators currently lack evidence to support the value of health IT. In this paper, we detail the development of a novel, easy-to-use system to facilitate electronic patient falls reporting within a LTRCF using off-the-shelf technology that can be inexpensively implemented in a wide variety of settings. We report the results of four complimentary system evaluation measures that take into consideration varied organizational stakeholders' perspectives: (1) System-level benefits and costs, (2) system usability, via scenario-based use cases, (3) a holistic assessment of users' physical, cognitive, and marcoergonomic (work system) challenges in using the system, and (4) user technology acceptance. We report the viability of collecting and analyzing data specific to each evaluation measure and detail the relative merits of each measure in judging whether the system is acceptable to each stakeholder. The electronic falls reporting system was successfully implemented, with 100% reporting at 3-months post-implementation. The system-level benefits and costs approach showed that the electronic system required no initial investment costs aside from personnel costs and significant benefits accrued from user time savings

  19. Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in the Hot-Dry and Mixed-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Building Industry Research Alliance (BIRA); Building Science Consortium (BSC); Consortium for Advanced Residential Buildings (CARB); Davis Energy Group (DEG); Florida Solar Energy Center (FSEC); IBACOS; National Association of Home Builders Research Center (NAHBRC); National Renewable Energy Laboratory (NREL)

    2006-01-01

    The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Hot-Dry/Mixed-Dry Climate Region on a cost neutral basis.

  20. Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Mixed-Humid Climates; January 2006 - December 2006

    Energy Technology Data Exchange (ETDEWEB)

    Building America Industrialized Housing Partnership (BAIHP); Building Industry Research Alliance (BIRA); Building Science Consortium (BSC); Consortium for Advanced Residential Buildings (CARB); Davis Energy Group (DEG); IBACOS; National Association of Home Builders Research Center (NAHBRC); National Renewable Energy Laboratory (NREL)

    2006-12-01

    The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Mixed-Humid Climate Region on a cost-neutral basis.

  1. Cleanliness of ventilation ducts, indoor space and AHU

    OpenAIRE

    Rubina, Aleš; Rubinová, Olga; Blasinski, Petr

    2015-01-01

    Paper deals with analysis of cleanliness air conditioning duct for various stages of construction. There were taken samples and these were analyzed for different type of storage duct on construction. They are compared differences between the "right" stored duct and unprotected duct including the actual interior space and air handling units serving. In the conclusion of this article is summarized the impact of carryover dirt from the duct and an air handling unit to the ventilation s...

  2. Residential Mechanical Precooling

    Energy Technology Data Exchange (ETDEWEB)

    German, a. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Hoeschele, M. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2014-12-01

    This research conducted by the Alliance for Residential Building Innovation team evaluated mechanical air conditioner pre-cooling strategies in homes throughout the United States. EnergyPlus modeling evaluated two homes with different performance characteristics in seven climates. Results are applicable to new construction homes and most existing homes built in the last 10 years, as well as fairly efficient retrofitted homes.

  3. Study of natural convection heat transfer characteristics. (1) Influence of ventilation duct height

    International Nuclear Information System (INIS)

    Wakamatsu, Mitsuo; Iwaki, Chikako; Ikeda, Tatsumi; Morooka, Shinichi; Ikeda, Hiroshi; Nakada, Kotaro; Masaki, Yoshikazu

    2008-01-01

    Natural cooling system has been investigated in waste storage. It is important to evaluate the flow by natural draft enough to removal the decay heat from the waste. In this study, we carried out the fundamental experiment of ventilation duct height effect for natural convection on vertical cylindrical heater in atmospheric air. The scale of test facility is about 4m height with single heater. The heating value is varied in the range of 33-110W, where Rayleigh number is over 10 10 . Natural convection flow rate were calculated by measured velocity with thermo anemometer in the inlet duct. The temperature of the cylindrical heater wall and fluid were measured with thermocouples. It was found that the heat transfer coefficient difference between long duct and short duct is small in this experiment. (author)

  4. Salivary duct cyst in the upper lip: Case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Filipe Nobre Chaves

    2013-01-01

    Full Text Available Salivary duct cyst (SDC in an uncommon lesion of the minor salivary glands, with etiology related to obstruction of the salivary duct. It presents with a color similar to that of the mucosa, is mobile, measures between 3 and 10 mm and affects preferentially the bottom lip, floor of the mouth and the jugal mucosa. SDC have a predilection for the male and individual in elderly groups. The pathogenesis of SDC is associated with the formation of a mucous plug that causes partial or total obstruction of the salivary gland system duct, resulting in the dilation of the duct and increase in intraluminal pressure. They present clinical-pathological characteristics similar to those of salivary gland tumors, making diagnosis difficult and subject to errors in treatment. It is important for the dentist to include SDC in the differential diagnosis of lesions that affect the upper lip, although it is relatively rarely found in this anatomic site.

  5. Salivary duct cyst in the upper lip: case report and review of the literature.

    Science.gov (United States)

    Chaves, Filipe Nobre; Carvalho, Francisco Samuel Rodrigues; Pereira, Karuza Maria Alves; Costa, Fabio Wildson Gurgel

    2013-01-01

    Salivary duct cyst (SDC) in an uncommon lesion of the minor salivary glands, with etiology related to obstruction of the salivary duct. It presents with a color similar to that of the mucosa, is mobile, measures between 3 and 10 mm and affects preferentially the bottom lip, floor of the mouth and the jugal mucosa. SDC have a predilection for the male and individual in elderly groups. The pathogenesis of SDC is associated with the formation of a mucous plug that causes partial or total obstruction of the salivary gland system duct, resulting in the dilation of the duct and increase in intraluminal pressure. They present clinical-pathological characteristics similar to those of salivary gland tumors, making diagnosis difficult and subject to errors in treatment. It is important for the dentist to include SDC in the differential diagnosis of lesions that affect the upper lip, although it is relatively rarely found in this anatomic site.

  6. Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

    International Nuclear Information System (INIS)

    Byoun, T.Y.; Babel, P.J.; Dajani, A.T.

    1977-01-01

    A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scattering is handled by a repeated process of the single scatter method through each successive scatter region and collapsed pseudo source meshes constructed on the relative coordinate systems. The SCAP-BR results have been compared with experimental data for a Z-type (three-legged) concrete duct with a Co-60 source placed at the duct entrance point. The SCAP-BR dose rate predictions along the duct axis demonstrate an excellent agreement with the measured values

  7. Numerical Investigation of the Transient Behavior of a Hot Gas Duct under Rapid Depressurization

    Directory of Open Access Journals (Sweden)

    JingBao Liu

    2016-01-01

    Full Text Available A hot gas duct is an indispensable component for the nuclear-process heat applications of the Very-High-Temperature Reactor (VHTR, which has to fulfill three requirements: to withstand high temperature, high pressure, and large pressure transient. In this paper, numerical investigation of pressure transient is performed for a hot gas duct under rapid depressurization. System depressurization imposes an imploding pressure differential on the internal structural elements of a hot gas duct, the structural integrity of which is susceptible to being damaged. Pressure differential and its imposed duration, which are two key factors to evaluate the damage severity of a hot gas duct under depressurization, are examined in regard to depressurization rate and insulation packing tightness. It is revealed that depressurization rate is a decisive parameter for controlling the pressure differential and its duration, whereas insulating-packing tightness has little effect on them.

  8. Solar Photovoltaic Financing: Residential Sector Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Coughlin, J.; Cory, K.

    2009-03-01

    This report presents the information that homeowners and policy makers need to facilitate PV financing at the residential level. The full range of cash payments, bill savings, and tax incentives is covered, as well as potentially available solar attribute payments. Traditional financing is also compared to innovative solutions, many of which are borrowed from the commercial sector. Together, these mechanisms are critical for making the economic case for a residential PV installation, given its high upfront costs. Unfortunately, these programs are presently limited to select locations around the country. By calling attention to these innovative initiatives, this report aims to help policy makers consider greater adoption of these models to benefit homeowners interested installing a residential PV system.

  9. Building America Case Study: Compact Buried Ducts in a Hot-Humid Climate House, Lady's Island, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely on encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences, 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs, and 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.

  10. Sizing a solar dish Stirling micro-CHP system for residential application in diverse climatic conditions based on 3E analysis

    International Nuclear Information System (INIS)

    Moghadam, Ramin Shabanpour; Sayyaadi, Hoseyn; Hosseinzade, Hadi

    2013-01-01

    Highlights: • 3E analysis was performed on solar CHP systems. • Significant primary energy saving and greenhouse gas reduction were obtained. • The engine was sized so that it had the best economic sound. • Various criteria at different weathers were used for sizing the engine. - Abstract: A solar dish Stirling cogeneration system is considered to provide energy demands of a residential building. As energy demands of the building and output power of the engine are functions of weather condition and solar irradiation flux, the benchmark building was considered to be located in five different cities in Iran with diverse climatic and solar irradiation conditions. The proposed solar dish Stirling micro-CHP system was analyzed based on 3E analysis. The 3E analysis evaluated primary energy saving analysis (energy analysis), carbon dioxide emission reduction (environmental analysis) and payback period for return of investment (economic analysis) and was compared to a reference building that utilized primary energy carriers for its demands. Three scenarios were considered for assessment and sizing the solar dish Stirling engine. In the first scenario, size of the solar dish Stirling engine was selected based on the lowest annual electric power demand while, in second, the highest annual electric power consumption was considered to specify size of the engine. In the third scenario, a solar dish Stirling engine with constant output capacity was considered for the five locations. It was shown that implementing the solar dish Stirling micro-CHP system had good potential in primary energy saving and carbon dioxide emission reduction in all scenarios and acceptable payback period for return of the investment in some scenarios. Finally, the best scenario for selecting size of the engine in each city was introduced using the TOPSIS decision making method. It was demonstrated that, for dry weather, the first scenario was the best while, for hot and humid cities and

  11. Dynamic performance assessment of a residential building-integrated cogeneration system under different boundary conditions. Part II: Environmental and economic analyses

    International Nuclear Information System (INIS)

    Rosato, Antonio; Sibilio, Sergio; Scorpio, Michelangelo

    2014-01-01

    Highlights: • A building-integrated micro-cogeneration system was dynamically simulated. • Simulation data were analyzed from both environmental and economic point of views. • The proposed system was compared with a conventional supply system. • The proposed system reduces the environmental impact under heat-led operation. • The proposed system reduces the operating costs whatever the control logic is. - Abstract: This work examines the performance of a residential building-integrated micro-cogeneration system during the winter by means of a whole building simulation software. The cogeneration unit was coupled with a multi-family house composed of three floors, compliant with the transmittance values of both walls and windows suggested by the Italian Law; a stratified combined tank for both heating purposes and domestic hot water production was also used for storing heat. Simulations were performed considering the transient nature of the building and occupant driven loads as well as the part-load characteristics of the cogeneration unit. This system was described in detail and analyzed from an energy point of view in the companion paper. In this paper the simulation results were evaluated in terms of both carbon dioxide equivalent emissions and operating costs; detailed analyses were performed in order to estimate the influence of the most significant boundary conditions on both environmental and economic performance of the proposed system: in particular, three volumes of the hot water storage, four climatic zones corresponding to four Italian cities, two electric demand profiles, as well as two control strategies micro-cogeneration unit were considered. The assessment of environmental impact was performed by using the standard emission factors approach, neglecting the effects of local pollutants. The operating costs due to both natural gas and electric energy consumption were evaluated in detail, whereas both the capital and maintenance costs were

  12. Ultrasound appearance of chronic mammary duct ectasia

    Energy Technology Data Exchange (ETDEWEB)

    Duchesne, N. [Ottawa Hospital, Dept. of Radiology, Ottawa, Ontario (Canada)]. E-mail: nathalie_duchesne_22@yahoo.ca; Skolnik, S. [Univ. of Toronto, Dept. of Family Medicine, Toronto, Ontario (Canada); Bilmer, S. [Ottawa Hospital, Dept. of Radiology, Ottawa, Ontario (Canada)

    2005-12-15

    Mammary duct ectasia (MDE), also called periductal mastitis, mammary dysplasia, or plasma cell mastitis, is a benign condition of the mammary gland first described by Haagensen in 1951. The etiology of MDE is unknown and its pathogenesis still controversial; the periductal inflammation could be either the cause or the result of dilated damaged ducts. The process is usually bilateral and asymptomatic, with only a small percentage of patients presenting with symptoms that may include long course of tumour formation, usually subareolar breast lumps, nipple discharge, nipple retraction, mastalgia, and mammary abscess or fistulas. Mammographic presentation of MDE is well known; its features include periductal calcification, benign intraductal calcification, and retroareolar duct dilatation. The periductal calcification results from dystrophic calcification and forms calcified rings or very dense, oval, elongated calcifications, each with a central lucency representing the dilated duct. Intraductal calcifications of duct ectasia represent inspissated intraductal material and are typically of uniform high density, often needle-like, and occasionally branching. Occasionally, there are no mammographic findings, and the diagnosis must rely on sonographic features. Appearance of MDE on ultrasonography (US) depends on the stage of the disease and the contents of the dilated ducts. The acute presentation has been demonstrated in the literature more often than has its chronic counterpart. In the former, duct content can vary from anechoic to isoechoic with surrounding fatty tissue. In chronic MDE, episodes of inflammation are longer. This tends to result in secretions that have a more solid, cheesy texture, partly due to cholesterol crystals, foam cells, and inflammatory cells. For both types of MDE, the appearance can mimic high-grade ductal carcinoma in situ (DCIS) on US. In this essay, 2 chronic MDE cases are presented and their US appearance discussed. Our goal is to explore

  13. Comparison of a Constant Air Volume (CAV) and a Demand Controlled Ventilation (DCV) System in a Residential Building

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer; Topp, Claus

    2008-01-01

    The aim of this paper was to compare the indoor climate and the energy performance of a Constant Air Volume (CAV) system of 0.5h-1 with a Demand Controlled Ventilation (DCV) system controlled by occupancy and relative humidity for a studio apartment. Furthermore the impact of building materials...... it was found that the energy consumption for heating and operating the ventilation system could be reduced by respectively 8.0% and 10.6 % in the case of DCV without negative impact on the indoor climate. Including the hygroscopic properties of the materials resulted in a reduction of the energy consumption...... for heating and operating the ventilation system by respectively 9.5% and 17.1 % in favour of the DCV system....

  14. Annex 3: BRIDGESIM, a simulation tool for the system design of bridge heating for ice prevention with solar heat stored in a seasonal ground duct store

    Energy Technology Data Exchange (ETDEWEB)

    Pahud, D.

    2006-12-15

    This is the Annex 3 of the annual report 2006 of the Serso project. This appendix provides details on the BRIDGESIM simulation tool for the simulation of a bridge heating system that uses heat stored in summer in a long-term diffusive borehole store to ensure an ice-free surface on a road bridge in winter. The operation of the control system which controls the heating system is described. The simulation tool is described and the various input parameters are discussed, as is the parametrisation of the tool itself. These parameters include not only timescales but also data on the borehole heat exchangers, data on the buried heating pipes in the road surface, thermal conductivity of the circulating heat-transfer fluid, ground parameters, intermediate water tank parameters and many other related data. The running of the simulation and output data are also described. Outputs are also presented in graphical form.

  15. The "flying" bile duct: avulsion of the common bile duct in a plane crash survivor.

    LENUS (Irish Health Repository)

    Mohan, H

    2012-02-01

    Blunt trauma is an unusual cause of extrahepatic bile duct injury. This is a case of a 51-year-old gentleman who sustained a significant seatbelt injury in a plane crash. Laparotomy, performed due to persistent abdominal pain, revealed that the common bile duct (CBD) was completely avulsed from the duodenum. Following insertion of drains and transfer to a hepatobiliary centre, the devascularised CBD was excised and replaced with a roux-en-y hepaticojejunostomy. Necrotic tissue was debrided from the pancreatic head. A persistent bile leak developed from the sub-hepatic drain. Repeat laparotomy revealed a bile leak from small ducts on the liver surface. Ligation of the ducts and bioglue sealing of the area were successfully performed. Subsequent to this a pancreatic fistula developed from the main pancreatic duct, which has since resolved. This unusual case illustrates the need for prompt recognition and early repair to optimise outcomes in traumatic CBD injury.

  16. ITER L 6 equatorial maintenance duct remote handling study

    International Nuclear Information System (INIS)

    Millard, J.

    1996-09-01

    The status and conclusions of a preliminary study of equatorial maintenance duct remote handling is reported. Due to issues with the original duct design a significant portion of the study had to be refocused on equatorial duct layout studies. The study gives an overview of some of the options for design of these ducts and the impact of the design on the equipment to work in the duct. To develop a remote handling concept for creating access through the ducts the following design tasks should be performed: define the operations sequences for equatorial maintenance duct opening and closing; review the remote handling requirements for equatorial maintenance duct opening and closing; design concept for door and pipe handling equipment and to propose preliminary procedures for material handling outsides the duct. 35 figs

  17. Examination of Duct Physiology in the Human Mammary Gland.

    Science.gov (United States)

    Mills, Dixie; Gomberawalla, Ameer; Gordon, Eva J; Tondre, Julie; Nejad, Mitra; Nguyen, Tinh; Pogoda, Janice M; Rao, Jianyu; Chatterton, Robert; Henning, Susanne; Love, Susan M

    2016-01-01

    The human breast comprise several ductal systems, or lobes, which contain a small amount of fluid containing cells, hormones, proteins and metabolites. The complex physiology of these ducts is likely a contributing factor to the development of breast cancer, especially given that the vast majority of breast cancers begin in a single lobular unit. We examined the levels of total protein, progesterone, estradiol, estrone sulfate, dehydroepiandrosterone sulfate, and macrophages in ductal fluid samples obtained from 3 ducts each in 78 women, sampled twice over a 6 month period. Samples were processed for both cytological and molecular analysis. Intraclass correlation coefficients and mixed models were utilized to identify significant data. We found that the levels of these ductal fluid components were generally uncorrelated among ducts within a single breast and over time, suggesting that each lobe within the breast has a distinct physiology. However, we also found that estradiol was more correlated in women who were nulliparous or produced nipple aspirate fluid. Our results provide evidence that the microenvironment of any given lobular unit is unique to that individual unit, findings that may provide clues about the initiation and development of ductal carcinomas.

  18. High-Performance Control of Paralleled Three-Phase Inverters for Residential Microgrid Architectures Based on Online Uninterruptable Power Systems

    DEFF Research Database (Denmark)

    Zhang, Chi; Guerrero, Josep M.; Vasquez, Juan Carlos

    2015-01-01

    In this paper, a control strategy for the parallel operation of three-phase inverters forming an online uninterruptible power system (UPS) is presented. The UPS system consists of a cluster of paralleled inverters with LC filters directly connected to an AC critical bus and an AC/DC forming a DC...... synchronization with an external real/fictitious utility, and critical bus voltage restoration. Constant transient and steady-state frequency, active, reactive and harmonic power sharing, and global phase-locked loop resynchronization capability are achieved. Detailed system topology and control architecture...

  19. Smart Control System to Optimize Time of Use in a Solar-Assisted Air-Conditioning by Ejector for Residential Sector

    Directory of Open Access Journals (Sweden)

    Giovanna Avedian-González

    2018-02-01

    Full Text Available The present work provides a series of theoretical improvements of a control strategy in order to optimize the time of use of solar air-conditioning by an ejector distributed in multiple solar collectors of vacuum tubes for the residential sector, which will allow us to reduce carbon-dioxide emissions, costs and electrical energy consumption. In a solar ejector cooling system, the instability of the solar source of energy causes an operational conflict between the solar thermal system and ejector cooling cycle. A fuzzy control structure for the supervisory ejector cycle and multi-collector control system is developed: the first control is applied to control the mass flow of the generator and the evaporator for different cooling capacities (3, 3.5, 4, 4.5 and 5 kW and set a temperature reference according to the operating conditions; the second is applied to keep a constant temperature power source that feeds the low-grade ejector cooling cycle using R134aas refrigerant. For the present work, the temperature of the generator oscillates between 65 °C and 90 °C, a condenser temperature of 30 °C and an evaporator temperature of 10 °C. For the purpose of optimization, there are different levels of performance for time of use: the Mode 0 (economic gives a performance of 17.55 h, Mode 5 (maximum cooling power 14.86 h and variable mode (variable mode of capacities 16.25 h, on average. Simulations are done in MATLAB-Simulink applying fuzzy logic for a mathematical model of the thermal balance. They are compared with two different types of solar radiation: real radiation and disturbed radiation.

  20. Evaluation of Technical and Utility Programmatic Challenges With Residential Forced-Air Integrated Space/Water Heat Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kingston, Tim [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Vadnal, Hillary [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Scott, Shawn [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Kalensky, Dave [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States)

    2016-12-01

    This multi-unit field demonstration of combined space and water heating (combi) systems was conducted to help document combi system installation and performance issues that needed to be addressed through research. The objective of the project was to put commercialized forced-air tankless combi units into the field through local contractors that were trained by manufacturers and GTI staff under the auspices of utility-implemented ETPs.