On variations of space-heating energy use in office buildings

International Nuclear Information System (INIS)

Lin, Hung-Wen; Hong, Tianzhen

2013-01-01

Highlights: • Space heating is the largest energy end use in the U.S. building sector. • A key design and operational parameters have the most influence on space heating. • Simulated results were benchmarked against actual results to analyze discrepancies. • Yearly weather changes have significant impact on space heating energy use. • Findings enable stakeholders to make better decisions on energy efficiency. - Abstract: Space heating is the largest energy end use, consuming more than seven quintillion joules of site energy annually in the U.S. building sector. A few recent studies showed discrepancies in simulated space-heating energy use among different building energy modeling programs, and the simulated results are suspected to be underpredicting reality. While various uncertainties are associated with building simulations, especially when simulations are performed by different modelers using different simulation programs for buildings with different configurations, it is crucial to identify and evaluate key driving factors to space-heating energy use in order to support the design and operation of low-energy buildings. In this study, 10 design and operation parameters for space-heating systems of two prototypical office buildings in each of three U.S. heating climates are identified and evaluated, using building simulations with EnergyPlus, to determine the most influential parameters and their impacts on variations of space-heating energy use. The influence of annual weather change on space-heating energy is also investigated using 30-year actual weather data. The simulated space-heating energy use is further benchmarked against those from similar actual office buildings in two U.S. commercial-building databases to better understand the discrepancies between simulated and actual energy use. In summary, variations of both the simulated and actual space-heating energy use of office buildings in all three heating climates can be very large. However

Solar Heating System with Building-Integrated Heat Storage

DEFF Research Database (Denmark)

Heller, Alfred

1996-01-01

Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating, and due to storage. Heat demand is reduced due to direct solar heating, due to storage and due to lower heat losses through the ground. In theory, by running the system flow backwards through the sand storage, active heating...... can be achieved.The objective of the report is to present results from measured system evaluation andcalculations and to give guidelines for the design of such solar heating systems with building integrated sand storage. The report is aimed to non-technicians. In another report R-006 the main results...

Localized Electrical Heating System for Various Types of Buildings

Science.gov (United States)

Shelehov, I. Y.; Smirnov, E. I.; Inozemsev, V. P.

2017-11-01

The article presents an overview of the factors determining the establishment of zones with high temperature in industrial, public and administrative buildings. The authors state the task on the improvement of the electric energy use efficiency and cost savings associated with the heating of these buildings by infrared electric heater devices. Materials and methods: The experiments were conducted in a room with the sizes of 3x6 m2 with a ceiling height of 3 m, the concrete floor was covered with laminate, in which increments of 250 mm were drilled and installed the thermocouple. In the process, had used the patented heating element with distributed heating layer. Signals from the thermocouples were recorded by instruments of the firm “ARIES” brand TPM138 with the standard software delivered together with devices (Owen Process Manager). The obtained distributions of the temperature fields were imported into MS Excel. Control voltage, current consumption, power was carried out by the device of firm “ARIES” brand of IMS. The results of the study: the article defines the purpose of the study and carried out the characterization of infrared heaters with various types of heating elements. The authors detail the main parameters of different types of infrared heaters, evaluated its possibility for application in other areas where the need to create areas of increased temperature. Discussion and conclusion: the result of this work it was determined that heating appliances that use patented heating element with distributed heating layer, improve thermal performance and bring you maximum comfort at a much greater distance compared to existing similar devices

IMPROVING THE EFFICIENCY OF THE HEATING SYSTEM FOR PUBLIC BUILDINGS INFRASTRUCTURE IN THE CONTEXT OF DNURT

Directory of Open Access Journals (Sweden)

O. M. Pshinko

2016-06-01

Full Text Available Purpose. The paper analyses the possibility and terms of increasing the efficiency of heating and ventilation systems of public buildings at the present stage of development and the specific climatic conditions of Ukraine. The main purpose is to develop specific measures for public buildings, which will lead to a significant reduction in energy costs for heating and air conditioning system. The example is similar system of DNURT compact campus, which is heated with its own autonomous boiler that uses natural gas. Methodology. The statistical heat loss analysis for the last 5 years allows defining the types and calculating the heat loss values for specific conditions. These losses are compared with those in the world practice and based on the comparison and analysis of the current system there are offered the ways to reduce the heat loss values through the use of various technical and organizational methods.The paper also proposes involvement for this purpose of secondary and alternative energy sources. The secondary energy resources include the heat that is emitted by people and that coming out with the air during ventilation of buildings. The renewable sources include solar and geothermal energy. To enhance the heat transfer medium temperature capacity it is proposed to use the heat pumps. Findings. The maximum possible use of the proposed measures and implementation of rational schematic and engineering solutions for heat and hot water supply systems cam reduce the energy loss for heating and hot water by 30-35%. Originality. The paper for the first time proposed the use of new integrated approaches to maintain the desired heat balance in the winter period, as well as the new schematic solutions for heating and ventilation systems, both in winter and in summer, based on the use of heat pumps and secondary energy resources. Practical value. The introduction of the proposed schematic solutions and approaches demand relatively small capital

Foundation heat transfer analysis for buildings with thermal piles

International Nuclear Information System (INIS)

Almanza Huerta, Luis Enrique; Krarti, Moncef

2015-01-01

Highlights: • A numerical transient thermal model for thermo-active foundations is developed. • Thermal interactions between thermal piles and building foundations are evaluated. • A simplified analysis method of thermal interactions between thermal piles and building foundations is developed. - Abstract: Thermal piles or thermo-active foundations utilize heat exchangers embedded within foundation footings to heat and/or cool buildings. In this paper, the impact of thermal piles on building foundation heat transfer is investigated. In particular, a simplified analysis method is developed to estimate the annual ground-coupled foundation heat transfer when buildings are equipped with thermal piles. First, a numerical analysis of the thermal performance of thermo-active building foundations is developed and used to assess the interactions between thermal piles and slab-on-grade building foundations. The impact of various design parameters and operating conditions is evaluated including foundation pile depth, building slab width, foundation insulation configuration, and soil thermal properties. Based on the results of a series of parametric analyses, a simplified analysis method is presented to assess the impact of the thermal piles on the annual heat fluxes toward or from the building foundations. A comparative evaluation of the predictions of the simplified analysis method and those obtained from the detailed numerical analysis indicated good agreement with prediction accuracy lower than 5%. Moreover, it is found that thermal piles can affect annual building foundation heat loss/gain by up to 30% depending on foundation size and insulation level

Using a gas-fired heat pump for heating and cooling in an office building

Energy Technology Data Exchange (ETDEWEB)

Bergmann, E [Westfaelische Ferngas-A.G., Dortmund (Germany, F.R.)

1979-01-01

Within the frame of the efforts made for a rational energy application by using new technologies, especially the long-known concept of heat pumps was prepared for heat production in swimming pools, sport centers, and buildings. Motivated by these activities, this technology was used, with additional heat recovery, for air-conditioning an administration building. After investigating various supply systems, an energy concept was processed with the aim to optimize the relation of the building costs to the operational costs of the air-condition, ventilation,- and heating systems.

Heat savings in buildings in a 100% renewable heat and power system in Denmark with different shares of district heating

DEFF Research Database (Denmark)

Zvingilaite, Erika; Balyk, Olexandr

2014-01-01

levels of heat savings, which can be implemented by reducing heat transmission losses through building elements and by installing ventilation systems with heat recovery, in different future Danish heat and power system scenarios. Today almost 50% of heat demand in Denmark is covered by district heating......The paper examines implementation of heat saving measures in buildings in 2050, under the assumption that heat and power supply comes solely from renewable resources in Denmark.Balmorel – a linear optimisation model of heat and power sectors in Denmark is used for investigating economically viable....... A further expansion of district heating network in Denmark is assessed and penetration of heat savings is analysed in this context.If all heat saving measures, included in the model, are implemented, heat demand in Danish buildings in 2050 could be reduced by around 40%. Results show that it is cost...

Heat Transmission Coefficient Measurements in Buildings Utilizing a Heat Loss Measuring Device

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt

2013-01-01

Global energy efficiency can be obtained in two ordinary ways. One way is to improve the energy production and supply side, and the other way is, in general, to reduce the consumption of energy in society. This paper has focus on the latter and especially the consumption of energy for heating...... and cooling our houses. There is a huge energy-saving potential in this area for reducing both the global climate problems as well as economy challenges. Heating of buildings in Denmark accounts for approximately 40% of the entire national energy consumption. For this reason, a reduction of heat losses from...... building envelopes are of great importance in order to reach the Bologna CO2 emission reduction targets. Upgrading of the energy performance of buildings is a topic of huge global interest these years. Not only heating in the temperate and arctic regions are important, but also air conditioning...

Analysis on exergy consumption patterns for space heating in Slovenian buildings

DEFF Research Database (Denmark)

Dovjak, Mateja; Shukuya, Masanori; Olesen, Bjarne W.

2010-01-01

and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler...... efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy...... emission rate and consequently better thermal comfort....

Optimization of heat saving in buildings using unsteady heat transfer model

Directory of Open Access Journals (Sweden)

Dedinec Aleksandra

2015-01-01

Full Text Available Reducing the energy consumption growth rate is increasingly becoming one of the main challenges for ensuring sustainable development, particularly in the buildings as the largest end-use sector in many countries. Along this line, the aim of this paper is to analyse the possibilities for energy savings in the construction of new buildings and reconstruction of the existing ones developing a tool that, in terms of the available heating technologies and insulation, provides answer to the problem of optimal cost effective energy consumption. The tool is composed of an unsteady heat transfer model which is incorporated into a cost-effective energy saving optimization. The unsteady heat transfer model uses annual hourly meteorological data, chosen as typical for the last ten-year period, as well as thermo physical features of the layers of the building walls. The model is tested for the typical conditions in the city of Skopje, Macedonia. The results show that the most cost effective heating technology for the given conditions is the wood fired stove, followed by the inverter air-conditioner. The centralized district heating and the pellet fired stoves are the next options. The least cost effective option is the panel that uses electricity. In this paper, the optimal insulation thickness is presented for each type of heating technology.

Technology Roadmaps: Energy-efficient Buildings: Heating and Cooling Equipment

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

Buildings account for almost a third of final energy consumption globally and are an equally important source of CO2 emissions. Currently, both space heating and cooling as well as hot water are estimated to account for roughly half of global energy consumption in buildings. Energy-efficient and low/zero-carbon heating and cooling technologies for buildings have the potential to reduce CO2 emissions by up to 2 gigatonnes (Gt) and save 710 million tonnes oil equivalent (Mtoe) of energy by 2050. Most of these technologies -- which include solar thermal, combined heat and power (CHP), heat pumps and thermal energy storage -- are commercially available today. The Energy-Efficient Buildings: Heating and Cooling Equipment Roadmap sets out a detailed pathway for the evolution and deployment of the key underlying technologies. It finds that urgent action is required if the building stock of the future is to consume less energy and result in lower CO2 emissions. The roadmap concludes with a set of near-term actions that stakeholders will need to take to achieve the roadmap's vision.

Initial operation of a solar heating and cooling system in a full-scale solar building test facility

Science.gov (United States)

Knoll, R. H.; Miao, D.; Hamlet, I. L.; Jensen, R. N.

1976-01-01

The Solar Building Test Facility (SBTF) located at Hampton, Virginia became operational in early summer of 1976. This facility is a joint effort by NASA-Lewis and NASA-Langley to advance the technology for heating and cooling of office buildings with solar energy. Its purposes are to (1) test system components which include high-performing collectors, (2) test performance of complete solar heating and cooling system, (3) investigate component interactions and (4) investigate durability, maintenance and reliability of components. The SBTF consists of a 50,000 square foot office building modified to accept solar heated water for operation of an absorption air conditioner and for the baseboard heating system. A 12,666 square foot solar collector field with a 30,000 gallon storage tank provides the solar heated water. A description of the system and the collectors selected is given here, along with the objectives, test approach, expected system performance and some preliminary results.

Solar heating and cooling of buildings

Science.gov (United States)

Bourke, R. D.; Davis, E. S.

1975-01-01

Solar energy has been used for space heating and water heating for many years. A less common application, although technically feasible, is solar cooling. This paper describes the techniques employed in the heating and cooling of buildings, and in water heating. The potential for solar energy to displace conventional energy sources is discussed. Water heating for new apartments appears to have some features which could make it a place to begin the resurgence of solar energy applications in the United States. A project to investigate apartment solar water heating, currently in the pilot plant construction phase, is described.

Space heating in buildings: thermal diagnosis of an industrial building; Chauffage des batiments: bilan thermique d`un batiment industriel

Energy Technology Data Exchange (ETDEWEB)

Brunet, R.

1996-12-31

The various heat transfer equations used for calculations in thermal diagnosis of an industrial building are reviewed: calculation of the heat losses through walls as a function of building materials, calculation of the energy consumption for heating fresh air (as a function of the air pollution rate in the building), calculation of the total heat losses, the heating energy demand and the annual energy consumption. Data concerning building materials characteristics, insulation and heating loads in the various regions of France, are also presented

Thermo Active Building Systems Using Building Mass To Heat and Cool

DEFF Research Database (Denmark)

Olesen, Bjarne W.

2012-01-01

Using the thermal storage capacity of the concrete slabs between each floor in multistory buildings to heat or cool is a trend that began in the early 1990s in Switzerland.1,2 Pipes carrying water for heating and cooling are embedded in the center of the concrete slab. In central Europe (Germany,......, Austria, Netherlands, etc.), this type of system has been installed in a significant number of new office buildings since the late 1990s. The trend is spreading to other parts of the world (the rest of Europe, North America and Asia)....

Nuclear heat for industrial purposes and district heating

International Nuclear Information System (INIS)

1974-01-01

Studies on the various possibilities for the application of heat from nuclear reactors in the form of district heat or process steam for industrial purposes had been made long before the present energy crisis. Although these studies have indicated technical feasibility and economical justification of such utilization, the availability of relatively cheap oil and difficulties in locating a nuclear heat source inside industrial areas did not stimulate much further development. Since the increase of oil prices, the interest in nuclear heat application is reawakened, and a number of new potential areas have been identified. It now seems generally recognized that the heat from nuclear reactors should play an important role in primary energy supply, not only for electricity production but also as direct heat. At present three broad areas of nuclear heat application are identified: Direct heat utilization in industrial processing requiring a temperature above 800 deg. C; Process steam utilization in various industries, requiring a temperature mainly in the range of 200-300 deg. C; Low temperature and waste heat utilization from nuclear power plants for desalination of sea water and district heating. Such classification is mainly related to the type and characteristics of the heat source or nuclear reactor which could be used for a particular application. Modified high temperature reactor types (HTR) are the candidates for direct heat application, while the LWR reactors can satisfy most of the demands for process steam. Production of waste heat is a characteristic of all thermal power plants, and its utilization is a major challenge in the field of power production

Modeling hourly consumption of electricity and district heat in non-residential buildings

International Nuclear Information System (INIS)

Kipping, A.; Trømborg, E.

2017-01-01

Models for hourly consumption of heat and electricity in different consumer groups on a regional level can yield important data for energy system planning and management. In this study hourly meter data, combined with cross-sectional data derived from the Norwegian energy label database, is used to model hourly consumption of both district heat and electrical energy in office buildings and schools which either use direct electric heating (DEH) or non-electric hydronic heating (OHH). The results of the study show that modeled hourly total energy consumption in buildings with DEH and in buildings with OHH (supplied by district heat) exhibits differences, e.g. due to differences in heat distribution and control systems. In a normal year, in office buildings with OHH the main part of total modeled energy consumption is used for electric appliances, while in schools with OHH the main part is used for heating. In buildings with OHH the share of modeled annual heating energy is higher than in buildings with DEH. Although based on small samples our regression results indicate that the presented method can be used for modeling hourly energy consumption in non-residential buildings, but also that larger samples and additional cross-sectional information could yield improved models and more reliable results. - Highlights: • Schools with district heating (DH) tend to use less night-setback. • DH in office buildings tends to start earlier than direct electric heating (DEH). • In schools with DH the main part of annual energy consumption is used for heating. • In office buildings with DH the main part is used for electric appliances. • Buildings with DH use a larger share of energy for heating than buildings with DEH.

Study on the simulation of heat pump heating and cooling systems to hospital building

International Nuclear Information System (INIS)

Choi, Young Don; Han, Seong Ho; Cho, Sung Hwan; Kim, Du Sung; Um, Chul Jun

2008-01-01

In Korea, air source heat pump system is less efficient than conventional heat source facilities, because the air temperature in winter season is so low that COP of air source heat pump system drops below 3.0. Therefore, the study on the application of heat pump heating and cooling systems is crucial for the efficient popularization of heat pump. In this work, we present the dynamic analysis of energy consumption for the large hospital building by heat resistance-capacitance method. The system simulation of water storage air source heat pump is additionally performed by changing sizes and locations of the hospital building. The computed results show that energy cost of water storage air source heat pump is low, so it is more economical than absorption chiller and heater

Human Health Science Building Geothermal Heat Pump Systems

Energy Technology Data Exchange (ETDEWEB)

Leidel, James [Oakland Univ., Rochester, MI (United States)

2014-12-22

The grant objectives of the DOE grant funded project have been successfully completed. The Human Health Building (HHB) was constructed and opened for occupancy for the Fall 2012 semester of Oakland University. As with any large construction project, some issues arose which all were overcome to deliver the project on budget and on time. The facility design is a geothermal / solar-thermal hybrid building utilizing both desiccant dehumidification and variable refrigerant flow heat pumps. It is a cooling dominant building with a 400 ton cooling design day load, and 150 ton heating load on a design day. A 256 vertical borehole (320 ft depth) ground source heat pump array is located south of the building under the existing parking lot. The temperature swing and performance over 2013 through 2015 shows the ground loop is well sized, and may even have excess capacity for a future building to the north (planned lab facility). The HHB achieve a US Green Building Counsel LEED Platinum rating by collecting 52 of the total 69 available LEED points for the New Construction v.2 scoring checklist. Being Oakland's first geothermal project, we were very pleased with the building outcome and performance with the energy consumption approximately 1/2 of the campus average facility, on a square foot basis.

Heat Loss Measurements in Buildings Utilizing a U-value Meter

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt

Heating of buildings in Denmark accounts for approximately 40% of the entire national energy consumption. For this reason, a reduction of heat losses from building envelopes are of great importance in order to reach the Bologna CO2 emission reduction targets. Upgrading of the energy performance...... of buildings is a topic of huge global interest these years. Not only heating in the temperate and arctic regions are important, but also air conditioning and mechanical ventilation in the tropical countries contribute to an enormous energy consumption and corresponding CO2 emission. In order to establish...... the best basis for upgrading the energy performance, it is important to measure the heat losses at different locations on a building facade, in order to optimize the energy performance. The author has invented a U-value meter, enabling measurements of heat transfer coefficients. The meter has been used...

Dissipation of heat from building integrated PV

Energy Technology Data Exchange (ETDEWEB)

Taylor, C.M.L.

2001-07-01

The objectives of the project were to investigate methods for improving heat transfer and the reflection of heat from PV modules in building integrated situations and to develop the design of a building integrated PV element with improved heat transfer characteristics, with the aim of reducing the operating temperature of the PV cells. The prototypes developed for improving heat transfer have only shown small reductions in the PV cell operating temperature and these results have not been fully quantified due to problems associated with experimental testing. The improvement in the overall electrical performance of PV modules operating at lower temperatures is consequently even smaller. As a result, none of the prototypes can be considered to be economically viable. Based upon the theoretical and experimental results of this work, it is the recommendation of this project that no further work be conducted in improving BIPV performance through improved heat transfer of BIPV. (Author)

The General-Purpose Heat Source Radioisotope Thermoelectric Generator: Power for the Galileo and Ulysses missions

International Nuclear Information System (INIS)

Bennett, G.L.; Lombardo, J.J.; Hemler, R.J.; Peterson, J.R.

1986-01-01

Electrical power for NASA's Galileo mission to Jupiter and ESA's Ulysses mission to explore the polar regions of the Sun will be provided by General-Purpose Heat Source Radioisotope Thermo-electric Generators (GPHS-RTGs). Building upon the successful RTG technology used in the Voyager program, each GPHS-RTG will provide at least 285 W(e) at beginning-of-mission. The design concept has been proven through extensive tests of an electrically heated Engineering Unit and a nuclear-heated Qualification Unit. Four flight generators have been successfully assembled and tested for use on the Galileo and Ulysses spacecraft. All indications are that the GPHS-RTGs will meet or exceed the power requirement of the missions

Quantifying demand flexibility of power-to-heat and thermal energy storage in the control of building heating systems

DEFF Research Database (Denmark)

Finck, Christian; Li, Rongling; Kramer, Rick

2018-01-01

restricted by power-to-heat conversion such as heat pumps and thermal energy storage possibilities of a building. To quantify building demand flexibility, it is essential to capture the dynamic response of the building energy system with thermal energy storage. To identify the maximum flexibility a building......’s energy system can provide, optimal control is required. In this paper, optimal control serves to determine in detail demand flexibility of an office building equipped with heat pump, electric heater, and thermal energy storage tanks. The demand flexibility is quantified using different performance...... of TES and power-to-heat in any case of charging, discharging or idle mode. A simulation case study is performed showing that a water tank, a phase change material tank, and a thermochemical material tank integrated with building heating system can be designed to provide flexibility with optimal control....

Building integration of concentrating solar systems for heating applications

International Nuclear Information System (INIS)

Tsoutsou, Sapfo; Infante Ferreira, Carlos; Krieg, Jan; Ezzahiri, Mohamed

2014-01-01

A new solar collection system integrated on the façade of a building is investigated for Dutch climate conditions. The solar collection system includes a solar façade, a receiver tube and 10 Fresnel lenses. The Fresnel lenses Fresnel lenses considered were linear, non-imaging, line – focused with a system tracking the position of the sun that ensures vertical incidence of the direct solar radiation on the lenses. For the heating system a double-effect absorption heat pump, which requires high temperature of the heating fluid, was used, working with water and lithium-bromide as refrigerant and solution respectively. The Fresnel lens system is connected with the absorption heat pump through a thermal energy storage tank which accumulates the heat from the Fresnel lens system to provide it to the high pressure generator of the absorption heat pump. - Highlights: • The integration of Fresnel lenses in solar thermal building façades is investigated. • Using building integrated Fresnel lenses, 43% heating energy can be saved. • Energy savings in Mediterranean countries are significantly larger. • The absorption heat pump could make great contribution to energy savings for Dutch climate conditions

Energy conservation in new and older buildings

Energy Technology Data Exchange (ETDEWEB)

Ehm, H

1978-07-01

For buildings, the building permits of which had been asked for after 1.9.77, new regulations according to the heat protection term are to be observed. The possibility of restricting heat losses, the simplified manifestation for restricting the transmission heat consumption and details of the new demands and the special regulation for neighbouring buildings are reported. Furthermore, the demands for restricting heat losses due to leaks and for the purpose of ventilation, as well as at buildings with low internal temperatures and buildings for sport and gathering purposes, are dealt with. The simplified heat balance calculation represents a key to the problem solution. In detail it is shown how to make a proper selection of improvement measures.

Energy sustainable development through energy efficient heating devices and buildings

International Nuclear Information System (INIS)

Bojic, M.

2006-01-01

Energy devices and buildings are sustainable if, when they operate, they use sustainable (renewable and refuse) energy and generate nega-energy. This paper covers three research examples of this type of sustainability: (1) use of air-to-earth heat exchangers, (2) computer control of heating and cooling of the building (via heat pumps and heat-recovery devices), and (3) design control of energy consumption in a house. (author)

Analyzing Design Heating Loads in Superinsulated Buildings

Energy Technology Data Exchange (ETDEWEB)

Arena, Lois [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

2015-06-16

The U.S. Department of Energy’s Building America research team Consortium for Advanced Residential Buildings (CARB) worked with the EcoVillage cohousing community in Ithaca, New York, on the Third Residential EcoVillage Experience neighborhood. This communityscale project consists of 40 housing units—15 apartments and 25 single-family residences. Units range in size from 450 ft2 to 1,664 ft2 and cost from $80,000 for a studio apartment to $235,000 for a three- or four-bedroom single-family home. For the research component of this project, CARB analyzed current heating system sizing methods for superinsulated homes in cold climates to determine if changes in building load calculation methodology should be recommended. Actual heating energy use was monitored and compared to results from the Air Conditioning Contractors of America’s Manual J8 (MJ8) and the Passive House Planning Package software. Results from that research indicate that MJ8 significantly oversizes heating systems for superinsulated homes and that thermal inertia and internal gains should be considered for more accurate load calculations.

Thermal models of buildings. Determination of temperatures, heating and cooling loads. Theories, models and computer programs

Energy Technology Data Exchange (ETDEWEB)

Kaellblad, K

1998-05-01

The need to estimate indoor temperatures, heating or cooling load and energy requirements for buildings arises in many stages of a buildings life cycle, e.g. at the early layout stage, during the design of a building and for energy retrofitting planning. Other purposes are to meet the authorities requirements given in building codes. All these situations require good calculation methods. The main purpose of this report is to present the authors work with problems related to thermal models and calculation methods for determination of temperatures and heating or cooling loads in buildings. Thus the major part of the report deals with treatment of solar radiation in glazing systems, shading of solar and sky radiation and the computer program JULOTTA used to simulate the thermal behavior of rooms and buildings. Other parts of thermal models of buildings are more briefly discussed and included in order to give an overview of existing problems and available solutions. A brief presentation of how thermal models can be built up is also given and it is a hope that the report can be useful as an introduction to this part of building physics as well as during development of calculation methods and computer programs. The report may also serve as a help for the users of energy related programs. Independent of which method or program a user choose to work with it is his or her own responsibility to understand the limits of the tool, else wrong conclusions may be drawn from the results 52 refs, 22 figs, 4 tabs

Primary energy use for heating in the Swedish building sector-Current trends and proposed target

International Nuclear Information System (INIS)

Johansson, P.; Nylander, A.; Johnsson, F.

2007-01-01

One goal of the Swedish energy policy is to reduce the amount of electricity used for heating in the building sector. This means to reduce the primary energy used for heating which in this paper is analyzed in the context of various heating technologies and CO 2 emissions. The analysis is applied to a region in Sweden (southern Sweden) for which detailed information on the energy infrastructure (the capital stock of the buildings and heating systems together with geographical variations in heat intensity) is available from a previous work [Johansson, P., Nylander, A., Johnsson, F., 2005. Electricity dependency and CO 2 emissions from heating in the Swedish building sector-current trends in conflict with governmental policy? Energy policy] and which is large enough to be assumed representative for Sweden as a whole. The detailed mapping of the energy infrastructure allows a good estimate on the rate at which the energy system can be expected to be replaced with respect to economical lifetime of the capital stock (the year 2025 in this case). Two scenarios are investigated; a target scenario for which energy savings are employed (e.g. improving climate shell in buildings) and oil and most of the electricity used for heating purposes are phased out and a second for which the current trend in the heating market continues. In the target scenario it is shown that although only applying commercially competitive heating technologies, it is possible to achieve a 47% reduction in primary energy use for heating with a 34% decrease in heat demand together with significant reduction in CO 2 emissions. However, the scenario which continues the current trends on the heating market instead yields an increase (of about 10%) in primary energy use (reduction in conversion efficiency) of the heating system of the region over the period studied, in spite of a slight decrease in heat demand (9%, mainly due to energy efficiency measures) as well as in CO 2 emissions. In light of the

Effect of Air Cleaning Technologies in Conjunction With the Use of Rotary Heat Exchangers in Residential Buildings

DEFF Research Database (Denmark)

Afshari, Alireza; Bergsøe, Niels Christian; Ekberg, Lars

2013-01-01

This study is part of a research project concerning the possibilities of applying efficient air cleaning technologies using rotary heat exchanger in residential buildings. The purpose of this project was to identify and adapt new air-cleaning technologies for implementation in HVAC systems...... with rotary air-to-air heat exchangers. For this purpose, a mechanical filter with low pressure drop and a 4 cm thick activated carbon filter were selected for testing in a laboratory environment. The measurements included testing of the filters, separately and combined, in a ductwork to study the efficiency...

General Purpose Heat Source Simulator

Science.gov (United States)

Emrich, Bill

2008-01-01

The General Purpose Heat Source (GPHS) simulator project is designed to replicate through the use of electrical heaters, the form, fit, and function of actual GPHS modules which generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of spacecraft subsystems and systems without sacrificing the quantity and quality of the test data gathered. Previous GPHS activities are centered around developing robust heater designs with sizes and weights that closely matched those of actual Pu238 fueled GPHS blocks. These efforts were successful, although their maximum temperature capabilities were limited to around 850 C. New designs are being pursued which also replicate the sizes and weights of actual Pu238 fueled GPHS blocks but will allow operation up to 1100 C.

Simultaneousness of room heating and ventilation air heating

International Nuclear Information System (INIS)

Mathisen, Hans Martin

2006-01-01

The report is part of NTNU-SINTEF's Smart Buildings program, Smart Energy Efficient Buildings (2002-2006), subprogram 3.1 Heating, ventilation and cooling systems. An important part of this subprogram is the development and implementation of heating distribution systems with low return temperature. A comparison has been made of the simultaneousness of room heating and ventilation air heating in six buildings. Existing measuring data with hourly measurements of effect requirements for the different purposes have been employed. Based on the measuring data the relation between the requirements for room heating and ventilation is estimated. A 'fictitious' return temperature has also been estimated. The result shows a significant variation between the buildings. For all there are short periods where the efficiency need for room heating and ventilation is equal (ml)

Influence of duration of thermal comfort provision on heating behavior of buildings

International Nuclear Information System (INIS)

Bojic, Milorad; Despotovic, Milan

2007-01-01

Because of the permanent dilemma whether residential buildings using district heating should be heated continually or discontinuously, we evaluated how the yearly heating load and the peak heating load of a small building in Serbia depend on the duration of thermal comfort provision. Using HTB2 software, a product of the Welsh School of Architecture, it was found that an increase in the duration of thermal comfort provision in the building from 16 h to 24 h increases the yearly heating load by 20%, reduces the peak heating load by up to 40% and may increase the number of new customers served with the same heating plant by up to 40%

Distribution of heating costs in multi-story apartment buildings

DEFF Research Database (Denmark)

Rose, Jørgen; Kragh, Jesper

2017-01-01

Under current rules in the Danish Meter Order at least 40% of the total heating costs in multi-story blocks of flats should be distributed by metering the consumption in individual apartments. This fixed share is the result of a previous study that showed that 40% of the total heating costs were...... used for space heating, 35% for production and heat loss associated with hot water consumption and finally 25% of heat losses in the heating system. It is interesting to investigate whether this distribution remains representative in both existing buildings, where older buildings still dominate......, as in newer and future standard of blocks of flats. Intuitively, we would like to settle 100% of the costs attributable to space heating, by individual meters. Thereby, tenants will pay for their own consumption which encourages energy savings. This is an excellent method for electricity, gas and water...

Heat demand profiles of energy conservation measures in buildings and their impact on a district heating system

International Nuclear Information System (INIS)

Lundström, Lukas; Wallin, Fredrik

2016-01-01

Highlights: • Energy savings impact on an low CO 2 emitting district heating system. • Heat profiles of eight building energy conservation measures. • Exhaust air heat pump, heat recovery ventilation, electricity savings etc. • Heat load weather normalisation with segmented multivariable linear regression. - Abstract: This study highlights the forthcoming problem with diminishing environmental benefits from heat demand reducing energy conservation measures (ECM) of buildings within district heating systems (DHS), as the supply side is becoming “greener” and more primary energy efficient. In this study heat demand profiles and annual electricity-to-heat factors of ECMs in buildings are computed and their impact on system efficiency and greenhouse gas emissions of a Swedish biomass fuelled and combined heat and power utilising DHS are assessed. A weather normalising method for the DHS heat load is developed, combining segmented multivariable linear regressions with typical meteorological year weather data to enable the DHS model and the buildings model to work under the same weather conditions. Improving the buildings’ envelope insulation level and thereby levelling out the DHS heat load curve reduces greenhouse gas emissions and improves primary energy efficiency. Reducing household electricity use proves to be highly beneficial, partly because it increases heat demand, allowing for more cogeneration of electricity. However the other ECMs considered may cause increased greenhouse gas emissions, mainly because of their adverse impact on the cogeneration of electricity. If biomass fuels are considered as residuals, and thus assigned low primary energy factors, primary energy efficiency decreases when implementing ECMs that lower heat demand.

The potential to supply low temperature district heating to existing building area

DEFF Research Database (Denmark)

Li, Hongwei; Svendsen, Svend

2013-01-01

Low-temperature district heating (LTDH) has the advantages as reduced network heat loss, improved quality match between energy supply and energy demand, and increased utilization of low-grade waste heat and renewable energy. The LTDH represents the next generation district heating (DH) system...... to supply existing building areas which are characterized with high heating demand needs to be examined. In this paper, the DH network deliverable capacity to supply LTDH to an existing building area is studied based on building thermal performance and DH network hydraulic performance simulation....

Performance analysis of air source heat pump system for office building

Energy Technology Data Exchange (ETDEWEB)

Han, Dong Won; KIm, Yong Chan [Korea University, Seoul (Korea, Republic of); Chang, Young Soo [School of Mechanical System Engineering, Kookmin University, Seoul (Korea, Republic of)

2016-11-15

In this study, the performance of an air source heat pump system installed in a commercial building is analyzed using the developed heat pump performance model and building load simulation data of several regions in Korea. The performance test of an air source heat pump system with a variable speed compressor is tested to develop model that considers changes in the performance characteristics of the heat pump system under various operating conditions. The heat pump system is installed in an environmental chamber, and the experimental equipment is set up according to the manufacturer' specifications as well as the AHRI 1230 test specifications. The performance test conditions of the heat pump system are selected using a central composite design method, in which 29 points for each cooling and heating mode are selected. The developed performance model based on experimental data predicts experimental values with an error of ±5 %. Building cooling and heating loads in three regions in Korea are analyzed using TRNSYS software, which includes standard building and weather data from Seoul, Daejeon and Busan in Korea. The effects of outdoor air temperature and part load ratio on the performance and regional monthly average power consumption of the heat pump system are analyzed.

Pre study. Prototype of CO2 heat pump system for heating and cooling of a larger building

International Nuclear Information System (INIS)

Stene, Joern; Jakobsen, Arne

2006-03-01

The activities concerning CO 2 heat pumps during NTNU-SINTEF's strategic research program SMARTBYGG (2002-2006) has lead to an increased interest in planning, building, installing and testing a prototype CO 2 heat pump for heating and cooling of a larger building. In cooperation with Statsbygg and Naeringslivets Idefond a p restudy was initiated in 2005, with the main aim to carry out a set of defined activities, preparing the ground for the realization of a prototype. The following subjects are treated in the p restudy: a technological assessment of the CO 2 heat pumps, a technological assessment of the interaction between the CO 2 heat pump and the secondary systems, a study of the possibilities regarding suitable CO 2 components including compressors, heat exchangers, valves etc., and a presentation of Teknotherm AS (Halden), a Norwegian industrial partner that can project, build and maintain a CO 2 heat pump prototype. During the project period Statsbygg has not found a suitable building where a prototype can be installed. It is recommended that further work is made on the realization of a CO 2 prototype plant by setting up a main project (ml)

Optimum operation of heating systems in office buildings. Automated error detection and analysis improves running building operation; Heizsysteme in Buerogebaeuden optimal betreiben. Automatisierte Fehlererkennung und -analyse verbessert den laufenden Gebaeudebetrieb

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Uwe

2013-06-01

Since 2010, various institutes, universities and consultancy companies have been conducting research on automated operation optimisation in larger buildings. For this purpose, they have developed procedures for commissioning and monitoring building services equipment systems, firstly for large heat supply units. These are currently being used and evaluated on an ongoing basis in seven office and school buildings. The aim is to make significant energy and cost savings, and to improve the level of convenience in the building.

Solar Heating/Cooling of Buildings: Current Building Community Projects. An Interim Report.

Science.gov (United States)

National Academy of Sciences - National Research Council, Washington, DC. Building Research Advisory Board.

Projects being carried out by the private sector involving the use of solar energy for heating and cooling buildings are profiled in this report. A substantial portion of the data were collected from a broad cross-section of the building community. Data collection efforts also involved the canvassing of the nearly 200 trade and professional…

Internal heat gain from different light sources in the building lighting systems

Directory of Open Access Journals (Sweden)

Suszanowicz Dariusz

2017-01-01

Full Text Available EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

Internal heat gain from different light sources in the building lighting systems

Science.gov (United States)

Suszanowicz, Dariusz

2017-10-01

EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output) were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

The Economics of Connecting of Small Buildings to Geothermal District Heating Systems

Energy Technology Data Exchange (ETDEWEB)

Rafferty, Kevin

2003-03-01

Many of the communities co-located with geothermal resources are very small and as a result the buildings they contain tend to be small as well. Generally, small buildings (10,000 ft2) use heating systems which are not hot water based. Since geothermal district heating systems deliver hot water, the costs associated with the conversion of small building heating systems to use hot water for heating is an issue of great influence in terms of the potential development of such systems. This paper examines the typical retrofit costs associated with conversion of small buildings and the level of savings necessary to attract the interest of owners. In general, the prospects for connection of such buildings based only on energy savings is not positive.

The economics of connecting of small buildings to geothermal district heating systems

Energy Technology Data Exchange (ETDEWEB)

Rafferty, Kevin

2001-01-01

Many of the communities co-located with geothermal resources are very small and as a result the buildings they contain tend to be small as well. Generally, small buildings (10,000 ft2) use heating systems which are not hot water based. Since geothermal district heating systems deliver hot water, the costs associated with the conversion of small building heating systems to use hot water for heating is an issue of great influence in terms of the potential development of such systems. This paper examines the typical retrofit costs associated with conversion of small buildings and the level of savings necessary to attract the interest of owners. In general, the prospects for connection of such buildings based only on energy savings is not positive.

Renewable energy for passive house heating. Part 1. Building description

Energy Technology Data Exchange (ETDEWEB)

Badescu, V. [Polytechnic Univ., Bucharest (Romania). Faculty of Mechanical Engineering; Sicre, B. [Technical Univ., Chemnitz (Germany). Computational Physics

2003-12-01

A passive house is a cost-efficient building that can manage throughout the heating period, due to its specific construction design, with more than 10 times less heat energy than the same building designed to standards presently applicable across Europe. Its extended thermal insulation and enhanced air-tightness removes the need for temperatures higher than 50 {sup o}C. This makes renewable energy sources particularly suitable for heating, cooling and domestic hot water production. Modeling of renewable energy usage for space heating requires as a preliminary stage the detailed description of the building structure, of the HVAC equipment and of the internal heat sources. This paper shows the main data used to model the thermal behavior of a passive house. Details about Pirmasens Passive House (Rhineland Palatinate, Germany) are given, as for example, the internal heat sources, including electric appliances, heat and humidity released by human bodies, thermal internal facilities as hot and cold water pipes. All these are quantified by using statistically derived data. A detailed time schedule for a standard German family with two adults and two children was prepared. It takes into account the national celebrations, vacation and weekends among others. (Author)

Building codes as barriers to solar heating and cooling of buildings

Energy Technology Data Exchange (ETDEWEB)

Meeker, F.O. III

1978-04-01

The application of building codes to solar energy systems for heating and cooling of buildings is discussed, using as typical codes the three model building codes most widely adopted by states and localities. Some potential barriers to solar energy systems are found, federal and state programs to deal with these barriers are discussed, and alternatives are suggested. To remedy this, a federal program is needed to encourage state adoption of standards and acceptance of certification of solar systems for code approval, and to encourage revisions to codes based on model legislation prepared for the federal government by the model codes groups.

Improving Automation Routines for Automatic Heating Load Detection in Buildings

Directory of Open Access Journals (Sweden)

Stephen Timlin

2012-11-01

Full Text Available Energy managers use weather compensation data and heating system cut off routines to reduce heating energy consumption in buildings and improve user comfort. These routines are traditionally based on the calculation of an estimated building load that is inferred from the external dry bulb temperature at any point in time. While this method does reduce heating energy consumption and accidental overheating, it can be inaccurate under some weather conditions and therefore has limited effectiveness. There remains considerable scope to improve on the accuracy and relevance of the traditional method by expanding the calculations used to include a larger range of environmental metrics. It is proposed that weather compensation and automatic shut off routines that are commonly used could be improved notably with little additional cost by the inclusion of additional weather metrics. This paper examines the theoretical relationship between various external metrics and building heating loads. Results of the application of an advanced routine to a recently constructed building are examined, and estimates are made of the potential savings that can be achieved through the use of the routines proposed.

Solar-heated and cooled savings and loan building-1-Leavenworth, Kanasas

Science.gov (United States)

1981-01-01

Report describes heating and cooling system which furnishes 90 percent of annual heating load, 70 percent of cooling load, and all hot water for two-story building. Roof-mounted flat-plate collectors allow three distinct flow rates and are oriented south for optimum energy collection. Building contains fully automated temperature controls is divided into five temperature-load zones, each with independent heat pump.

Integrated evaluation of radiative heating systems for residential buildings

International Nuclear Information System (INIS)

Anastaselos, Dimitrios; Theodoridou, Ifigeneia; Papadopoulos, Agis M.; Hegger, Manfred

2011-01-01

Based on the need to reduce CO 2 emissions and minimize energy dependency, the EU Member States have set ambitious energy policies goals and have developed respective, specific regulations, in order to improve the energy performance of the building sector. Thus, specific measures regarding the buildings' envelope, the use of efficient HVAC technologies and the integration of renewable energy systems are being constantly studied and promoted. The effective combination of these three main aspects will consequently result in maximum energy efficiency. Germany has played a key role in this development, with intensive work focusing in the improvement of the energy behaviour of the residential building stock. In this paper, the use of radiative heating systems placing special emphasis on infrared is being studied as part of the energy renovation of residential buildings from the 1970's. This is done by applying an integrated assessment model to evaluate specific interventions regarding the improvement of the energy behaviour of the buildings' envelope and the use of radiative heating systems, based on a thorough Life Cycle Analysis according to criteria of energy, economic and environmental performance, as well as thermal comfort. -- Highlights: → Assessment of energy, economic and environmental performance of heating systems. → Life Cycle Analysis in combination with the quality of thermal comfort. → Effectiveness of interventions in already partially insulated buildings.

Heating load of buildings. Room heat from decentralized renewable electricity; Heizlast von Gebaeuden. Raumwaerme aus dezentral erneuerbarem Strom

Energy Technology Data Exchange (ETDEWEB)

Hartmann, Frank

2013-10-15

If one would like to get the heating load of a building by using peripheral generated electrical energy from photovoltaics or small wind power, one must deal with both the specific building, as well as the heating load, the heating temperature limit and the differentiation of specific heating period for the building. Here, a ground source heat pump with an intelligent energy storage system seems to be the first choice. [German] Moechte man mit dezentral erzeugter elektrischer Energie aus Photovoltaik oder Kleinst-Windkraft die Heizlast eines Gebaeudes besorgen, muss man sich sowohl mit dem spezifischen Gebaeude, als auch mit der Heizlast, der Heizgrenztemperatur und der Differenzierung der spezifischen Heizperiode fuer das Gebaeude auseinandersetzen. Dabei scheint eine erdgekoppelte Waermepumpe mit einem intelligenten Speichersystem die erste Wahl.

Estimation of the Relationship Between Remotely Sensed Anthropogenic Heat Discharge and Building Energy Use

Science.gov (United States)

Zhou, Yuyu; Weng, Qihao; Gurney, Kevin R.; Shuai, Yanmin; Hu, Xuefei

2012-01-01

This paper examined the relationship between remotely sensed anthropogenic heat discharge and energy use from residential and commercial buildings across multiple scales in the city of Indianapolis, Indiana, USA. The anthropogenic heat discharge was estimated with a remote sensing-based surface energy balance model, which was parameterized using land cover, land surface temperature, albedo, and meteorological data. The building energy use was estimated using a GIS-based building energy simulation model in conjunction with Department of Energy/Energy Information Administration survey data, the Assessor's parcel data, GIS floor areas data, and remote sensing-derived building height data. The spatial patterns of anthropogenic heat discharge and energy use from residential and commercial buildings were analyzed and compared. Quantitative relationships were evaluated across multiple scales from pixel aggregation to census block. The results indicate that anthropogenic heat discharge is consistent with building energy use in terms of the spatial pattern, and that building energy use accounts for a significant fraction of anthropogenic heat discharge. The research also implies that the relationship between anthropogenic heat discharge and building energy use is scale-dependent. The simultaneous estimation of anthropogenic heat discharge and building energy use via two independent methods improves the understanding of the surface energy balance in an urban landscape. The anthropogenic heat discharge derived from remote sensing and meteorological data may be able to serve as a spatial distribution proxy for spatially-resolved building energy use, and even for fossil-fuel CO2 emissions if additional factors are considered.

Heat recovery in compost piles for building applications

Directory of Open Access Journals (Sweden)

Walther Edouard

2017-01-01

Full Text Available This work proposes an estimation of the possible heat recovery of self-heating compost piles for building applications. The energy released during the aerobic composting of lignin and cellulose-based materials is computed by solving an inverse problem. The method consists first in an experimental phase with measurement of the temperature within the heap, then a numerical procedure allows for the inverse identification of the heat production due to the chemical reaction of composting. The simulation results show a good accordance with the experiments for the chosen source-term model. Comparing the results to the theoretical values for the energy released by aerobic composting provides an estimate for the efficiency of the reaction. The reached temperatures and recovered energy fit with the order of magnitude of building needs.

Geothermal energy - effective solutions for heating and cooling of buildings

International Nuclear Information System (INIS)

Veleska, Viktorija

2014-01-01

Energy and natural resources are essential prerequisites for the maintenance of the life and the development of human civilization. With the advancement of technology is more emphasis on energy efficiency and reducing carbon dioxide emissions. Energy efficiency is using less power without reducing the quality of life. Almost half of the energy used is devoted to buildings, including heating and cooling. Buildings are a major source of CO_2 emissions in the atmosphere. Reducing the impact of buildings on the environment and the development of renewable energy, energy solutions are key factor in terms of sustainable development. Energy and geothermal pumps posts represent effective solutions for large facilities for heating and cooling. Geothermal energy piles represent a system of pipes that circulate thermal fluid and embedded in earth, thus extracting heat from the bearing to satisfy the needs for heating and cooling. Experience has shown that this type of energy piles can save up to two thirds of the cost of conventional heating, while geothermal pump has the ability to low temperature resources (such as groundwater and earth) to extract energy and raise the higher level needed for heating buildings. Their implementation is supported by an active group of researchers working with industry to demonstrate the benefits of dual benefit performance at the foundations. Initiative for renewable heat and potential for further adoption of solutions with these technologies is rapidly expanding. The use of this source of energy has great potential due to environmental, economic and social benefits. (author)

Economic Model Predictive Control for Hot Water Based Heating Systems in Smart Buildings

DEFF Research Database (Denmark)

Awadelrahman, M. A. Ahmed; Zong, Yi; Li, Hongwei

2017-01-01

This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating system consists of an air source heat pump (ASHP) incorporated with a hot water tank...... as active Thermal Energy Storage (TES), where two optimization problems are integrated together to optimize both the ASHP electricity consumption and the building heating consumption utilizing a heat dynamic model of the building. The results show that the proposed EMPC can save the energy cost by load...

Heat pump and PV impact on residential low-voltage distribution grids as a function of building and district properties

International Nuclear Information System (INIS)

Protopapadaki, Christina; Saelens, Dirk

2017-01-01

of loading and voltage magnitude. Furthermore, rural feeders are more prone to overloading and under-voltage problems than urban ones. For large rural feeders, cable overloading can be expected already from 30% heat pump penetration, depending on the cable, while voltage problems start usually at slightly higher percentages. Additionally, building characteristics show high correlations with the examined grid performance indicators, revealing promising potential for statistical modeling of the studied indicators. Further work will be directed to the assessment of meta-modeling techniques for this purpose. The presented models and methodology can easily incorporate other technologies or scenarios and could be used in support of policy making or network design.

Assessment of infiltration heat recovery and its impact on energy consumption for residential buildings

International Nuclear Information System (INIS)

Solupe, Mikel; Krarti, Moncef

2014-01-01

Highlights: • Five steady-state air infiltration heat recovery or IHR models are described and compared. • IHR models are incorporated within whole-building simulation analysis tool. • IHR can reduce the thermal loads of residential buildings by 5–30%. - Abstract: Infiltration is a major contributor to the energy consumption of buildings, particularly in homes where it accounts for one-third of the heating and cooling loads. Traditionally, infiltration is calculated independent of the building envelope performance, however, it has been established that a thermal coupling exists between the infiltration and conduction heat transfer of the building envelope. This effect is known as infiltration heat recovery (IHR). Experiments have shown that infiltration heat recovery can typically reduce the infiltration thermal load by 10–20%. Currently, whole-building energy simulation tools do not account for the effect of infiltration heat recovery on heating and cooling loads. In this paper, five steady-state IHR models are described to account for the thermal interaction between infiltration air and building envelope components. In particular, inter-model and experimental comparisons are carried out to assess the prediction accuracy of five IHR models. In addition, the results from a series of sensitivity analyses are presented, including an evaluation of the predictions for heating energy use associated with four audited homes obtained from whole-building energy simulation analysis with implemented infiltration heat recovery models. Experimental comparison of the IHR models reveal that the predictions from all the five models are consistent and are within 2% when 1-D flow and heat transfer conditions are considered. When implementing IHR models to a whole-building simulation environment, a reduction of 5–30% in heating consumption is found for four audited residential homes

Effect of phase change material on the heat transfer rate of different building materials

Science.gov (United States)

Hasan, Mushfiq; Alam, Shahnur; Ahmed, Dewan Hasan

2017-12-01

Phase change material (PCM) is widely known as latent heat storage. A comprehensive study is carried out to investigate the effect of PCM on heat transfer rate of building materials. Paraffin is used as PCM along with different conventional building materials to investigate the heat transfer rate from the heated region to the cold region. PCM is placed along with the three different types of building materials like plaster which is well know building material in urban areas and wood and straw which are commonly used in rural areas for roofing as well as wall panel material and investigated the heat transfer rate. An experimental setup was constructed with number of rectangular shape aluminum detachable casing (as cavity) and placed side by side. Series of rectangular cavity filled with convent ional building materials and PCM and these were placed in between two chambers filled with water at different temperature. Building materials and PCM were placed in different cavities with different combinations and investigated the heat transfer rate. The results show that using the PCM along with other building materials can be used to maintain lower temperature at the inner wall and chamber of the cold region. Moreover, the placement or orientation of the building materials and PCM make significant contribution to heat transfer rate from the heated zone to the cold zone.

Modelling energy savings in the Danish building sector combined with internalisation of health related externalities in a heat and power system optimisation model

International Nuclear Information System (INIS)

Zvingilaite, Erika

2013-01-01

A substantial untapped energy saving potential rests in the building sector and is expected to play an important role in achieving reduction of environmental impacts of energy. In order to utilise this potential, effective policy measures need to be adopted to remove the existing barriers and create incentives. For that purpose, the cost effective energy saving options together with an optimal level of savings and expected environmental benefits have to be identified. The paper reports on a study that analyses these questions by including heat-saving measures in buildings into an energy system optimisation model of the Danish heat and power sector. The achieved optimal level of heat savings reaches 11% of projected heat demand in 2025 under the model assumptions. Moreover, the analysis reveals the importance of considering energy conservation options in a system wide perspective. Furthermore, the results suggest that changes in the energy generation sector are the prime driver behind the reduction of environmental externalities of energy. Heat savings in buildings play only a small role under model assumptions. - Highlights: ► Heat savings in buildings are analysed together with a heat and power system. ► Heat savings compete with electricity to heat technologies, mainly heat pumps. ► Cost effective heat-savings bring small decrease in health impacts and CO 2 emissions. ► Cost-effectiveness of heat savings depends on the marginal heat generation technology

Numerical simulation of solar heating of buildings. Final report

Energy Technology Data Exchange (ETDEWEB)

Coffe, G.; Jannot, M.; Pellerin, J.F.

1980-01-01

This study is divided into two parts: First, the thermal modelling of a solar + electric heated building is presented; mathematical equations are established; numerical calculations are analyzed; and a calculation code in FORTRAN V is set down. Second, this calculation code was used to study the thermal performances of the solar + electric heated building in three European climates: Copenhagen (56/sup 0/ north latitude - Denmark), Trappes (48/sup 0/ north latitude - France), and Carpentras (44/sup 0/ north latitude - France).

System impact of energy efficient building refurbishment within a district heated region

International Nuclear Information System (INIS)

Lidberg, T.; Olofsson, T.; Trygg, L.

2016-01-01

The energy efficiency of the European building stock needs to be increased in order to fulfill the climate goals of the European Union. To be able to evaluate the impact of energy efficient refurbishment in matters of greenhouse gas emissions, it is necessary to apply a system perspective where not only the building but also the surrounding energy system is taken into consideration. This study examines the impact that energy efficient refurbishment of multi-family buildings has on the district heating and the electricity production. It also investigates the impact on electricity utilization and emissions of greenhouse gases. The results from the simulation of four energy efficiency building refurbishment packages were used to evaluate the impact on the district heating system. The packages were chosen to show the difference between refurbishment actions that increase the use of electricity when lowering the heat demand, and actions that lower the heat demand without increasing the electricity use. The energy system cost optimization modeling tool MODEST (Model for Optimization of Dynamic Energy Systems with Time-Dependent Components and Boundary Conditions) was used. When comparing two refurbishment packages with the same annual district heating use, this study shows that a package including changes in the building envelope decreases the greenhouse gas emissions more than a package including ventilation measures. - Highlights: • Choice of building refurbishment measures leads to differences in system impact. • Building refurbishment in district heating systems reduces co-produced electricity. • Valuing biomass as a limited resource is crucial when assessing global GHG impact. • Building envelope measures decrease GHG (greenhouse gas) emissions more than ventilation measures.

Solar-Heated and Cooled Office Building--Columbus, Ohio

Science.gov (United States)

1982-01-01

Final report documents solar-energy system installed in office building to provide space heating, space cooling and domestic hot water. Collectors mounted on roof track Sun and concentrate rays on fluid-circulating tubes. Collected energy is distributed to hot-water-fired absorption chiller and space-heating and domestic-hot-water preheating systems.

Decreasing of energy consumption for space heating in existing residential buildings

International Nuclear Information System (INIS)

Stamov, S.; Zlateva, M.; Gechkov, N.

2000-01-01

An analysis is for the technical possibilities for reducing the energy consumption in existing buildings by means of the heat control and measurement. The basic performances of the heat capacity control methods, of the hierarchy structure of the control and of the heat measurement technologies are presented. This paper also presents the results from the long-term investigation of energy consumption for heating. The results area consist of three typical and uniform buildings in the city of Kazanlak (Bulgaria). The outcome of the investigation provides a valuable basis for future decisions to be made concerning reconstruction of heating installations and enables the results to be transferred. (Authors)

Effect of LED lighting on the cooling and heating loads in office buildings

International Nuclear Information System (INIS)

Ahn, Byung-Lip; Jang, Cheol-Yong; Leigh, Seung-Bok; Yoo, Seunghwan; Jeong, Hakgeun

2014-01-01

Highlights: • Application of heat control strategy reduces total energy consumption of LED lighting. • Convective heat from LED lighting should be emitted outdoors during cooling period. • Seasonal optimization of convective heat lowers total energy consumption. - Abstract: LED lighting has the potential to provide energy savings, and in many countries, there are policies to encourage its use owing to its higher efficiency and longer life in comparison to other lighting fixtures. However, since 75–85% of the light electric power in LED lights is still generated as heat, the sole use of LED lighting in a building could have a negative effect on the cooling load. In this paper, we study the heating properties of LED lighting and establish a management strategy to exploit these properties to reduce the energy used for heating and cooling of buildings. Using a simulation program, the energy consumption of the Green Building in Daejeon, Korea, and the virtual building provided by the U.S. Department of Energy (DOE) was computed according for different light fixtures. A control strategy is more applicable to LED lighting than to general fluorescent lighting, especially for the cooling of a building, because the use of a return-air duct and the heat sinks on the LED fixtures allow the heat to be better directed. Deployment of LED lights in combination with such a control strategy can help to increase the energy efficiency of a building

Experimental and Numerical Analysis of Air Flow, Heat Transfer and Thermal Comfort in Buildings with Different Heating Systems

Directory of Open Access Journals (Sweden)

Sabanskis A.

2016-04-01

Full Text Available Monitoring of temperature, humidity and air flow velocity is performed in 5 experimental buildings with the inner size of 3×3×3 m3 located in Riga, Latvia. The buildings are equipped with different heating systems, such as an air-air heat pump, air-water heat pump, capillary heating mat on the ceiling and electric heater. Numerical simulation of air flow and heat transfer by convection, conduction and radiation is carried out using OpenFOAM software and compared with experimental data. Results are analysed regarding the temperature and air flow distribution as well as thermal comfort.

Quasi-adaptive fuzzy heating control of solar buildings

Energy Technology Data Exchange (ETDEWEB)

Gouda, M.M. [Faculty of Industrial Education, Cairo (Egypt); Danaher, S. [University of Northumbria, Newcastle upon Tyne, (United Kingdom). School of Engineering; Underwood, C.P. [University of Northumbria, Newcastle upon Tyne (United Kingdom). School of Built Environment and Sustainable Cities Research Institute

2006-12-15

Significant progress has been made on maximising passive solar heat gains to building spaces in winter. Control of the space heating in these applications is complicated due to the lagging influence of the useful solar heat gain coupled with the wide range of construction materials and heating system choices. Additionally, and in common with most building control applications, there is a need to develop control solutions that permit simple and transparent set-up and commissioning procedures. This paper addresses the development and testing of a quasi-adaptive fuzzy logic control method that addresses these issues. The controller is developed in two steps. A feed-forward neural network is used to predict the internal air temperature, in which a singular value decomposition (SVD) algorithm is used to remove the highly correlated data from the inputs of the neural network to reduce the network structure. The fuzzy controller is then designed to have two inputs: the first input being the error between the set-point temperature and the internal air temperature and the second the predicted future internal air temperature. The controller was implemented in real-time using a test cell with controlled ventilation and a modulating electric heating system. Results, compared with validated simulations of conventionally controlled heating, confirm that the proposed controller achieves superior tracking and reduced overheating when compared with the conventional method of control. (author)

Thermal Models for Intelligent Heating of Buildings

DEFF Research Database (Denmark)

Thavlov, Anders; Bindner, Henrik W.

2012-01-01

the comfort of residents, proper prediction models for indoor temperature have to be developed. This paper presents a model for prediction of indoor temperature and power consumption from electrical space heating in an office building, using stochastic differential equations. The heat dynamic model is build......The Danish government has set the ambitious goal that the share of the total Danish electricity consumption, covered by wind energy, should be increased to 50% by year 2020. This asks for radical changes in how we utilize and transmit electricity in the future power grid. To fully utilize the high...... share of renewable power generation, which is in general intermittent and non-controllable, the consumption side has to be much more flexible than today. To achieve such flexibility, methods for moving power consumption in time, within the hourly timescale, have to be developed. One approach currently...

Efficiency analysis of solar facilities for building heating and household water heating under conditions in the Czech Republic

OpenAIRE

Pivko, Michal; Jursová, Simona; Turjak, Juraj

2012-01-01

The paper studies the efficiency of solar facilities applied for the heating of buildings and household water heating in the Czech Republic. The Czech Republic is situated in the temperate zone characterized by changeable weather. It is respected in the assessment of a solar facility installation. The efficiency of solar facilities is evaluated according to energy and economic balances. It is analyzed for solar facilities heating both household water and buildings. The main problems relating ...

AUTOMATED SYSTEM OF OPERATIONAL CONTROL HEATING AND AIR CONDITIONING OF BUILDINGS

Directory of Open Access Journals (Sweden)

PETRENKO A. O.

2016-08-01

accuracy manage experimentally investigate the electrical field in the liquid conducting medium as an analog of the thermal field [7, 8]. Isolation of previously solved problems. Known methods for modeling are approximate and have drawbacks that reduce the accuracy and limited scope. Therefore, one way to obtain effective thermal solutions is a simulation of thermal processes with further analysis of the results. It was suggested that the thermal field in the room to simulate electric field in the plating bath, and the analog heat flux between surfaces of any room space assumed current density between the surfaces of the model. The smaller the distance between the selected measurement points, the more accurate will be recreated actual picture patterns in the electric field and hence the thermal field in the room [7, 8]. But this method does not enable to take into account all the possible variations that affect the formation of indoor climate. Working with models that use an electric field to the heat radiation transfer simulations showed a significant labor input in the input model of the initial information and the removal of the simulation results. Objectives. Describe the behavior of the system (the influence of the microclimate of the environment and the geometric dimensions of the room, and thermal performance building envelopes, and the location of the premises (Orientation, and many other factors in the indoor climate of buildings, to build theories and hypotheses that could explain the behavior, which It will be observed to use the theory for predicting the future behavior of the system, that is, those factors that can be caused by a change in the system or change the way of its functioning. Conclusions. The proposed approach to addressing the issues raised will reveal the point of interaction between the different elements and factors that affect the indoor climate of buildings for different purposes. In the future, use the simulation method to study changes in

Use Of Snow And Ice Melting Heating Cables On Roofs Of Existing Buildings

Directory of Open Access Journals (Sweden)

Metin ONAL

2017-12-01

Full Text Available Roofs are construction elements which form the upper part of a building and protect it from the all kinds of fall wind and sun lights. They are made as inclined or terrace shaped according to the climatic characteristics of the area they are located and their intended use. Inclined type roofs are preferred for aesthetic and or functionality. It is in interest of mechanical engineering that falling snow on long and effective regions of winter conditions accumulate on the roof surfaces with low inclination due to adhesion force between snowflakes and the roof covering. The mass of snow that turns into ice due to cold weather and wind creates stalactites in the eaves due to gravity. This snow mass leavesbreaks off from inclined surfaces due to the effect of the sun or any vibration and can damage to people or other objects around the building. Falling snow and ice masses from rooftops in urban areas where winter months are intense are also a matter for engineering applications of landscape architecture. In order to prevent snow and icing on the roofs of the buildings located especially in busy human and vehicle traffic routes the use of heating cables is a practical method. The icing can be prevented by means of the heating cables selected according to the installed power to be calculated based on the type of roof and the current country. The purpose of this study is to introduce heating systems to be mounted on the roofs with a lesser workmanship in a short period instead of difficulties and costs that would occur by increasing the roof inclination in present buildings as well as explaining their working principles.

Analysis of Fuel Cell Driven Ground Source Heat Pump Systems in Community Buildings

Directory of Open Access Journals (Sweden)

Jong-Keun Shin

2013-05-01

Full Text Available In the present study, a fuel cell driven ground source heat pump (GSHP system is applied in a community building and heat pump system performance is analyzed by computational methods. Conduction heat transfer between the brine pipe and ground is analyzed by TEACH code in order to predict the performance of the heat pump system. The predicted coefficient of performance (COP of the heat pump system and the energy cost were compared with the variation of the location of the objective building, the water saturation rate of the soil, and the driven powers of the heat pump system. Compared to the late-night electricity driven system, a significant reduction of energy cost can be accomplished by employing the fuel cell driven heat pump system. This is due to the low cost of electricity production of the fuel cell system and to the application of the recovered waste heat generated during the electricity production process to the heating of the community building.

Simulation Tests in Whole Building Heat and Moisture Transfer

DEFF Research Database (Denmark)

Rode, Carsten; Peuhkuri, Ruut Hannele; Woloszyn, Monika

2006-01-01

An important part of the International Energy Agency project, ECBCS, Annex 41 is about modelling the integral heat, air and moisture transfer processes that take place in “whole buildings”. Such modelling deals with all most relevant elements of buildings: The indoor air, the building envelope...

Solar Systems for Heating and Cooling of Buildings

OpenAIRE

Henning, Hans-Martin; Döll, Jochen

2012-01-01

Recently, the concept of net zero energy buildings has become a major topic in the R&D work on future buildings. In order to achieve a zero energy balance on annual level energy saving and energy efficiency measures have to be fully exploited. However, a demand for active heating and/or cooling will remain in most buildings and under most climatic conditions. Solar energy is the main on-site renewable energy source which can be used to achieve a high fraction of renewable energies to cover th...

General purpose heat source task group. Final report

International Nuclear Information System (INIS)

1979-01-01

The results of thermal analyses and impact tests on a modified design of a 238 Pu-fueled general purpose heat source (GPHS) for spacecraft power supplies are presented. This work was performed to establish the safety of a heat source with pyrolytic graphite insulator shells located either inside or outside the graphite impact shell. This safety is dependent on the degree of aerodynamic heating of the heat source during reentry and on the ability of the heat source capsule to withstand impact after reentry. Analysis of wind tunnel and impact test data result in a recommended GPHS design which should meet all temperature and safety requirements. Further wind tunnel tests, drop tests, and impact tests are recommended to verify the safety of this design

Technology line and case analysis of heat metering and energy efficiency retrofit of existing residential buildings in Northern heating areas of China

International Nuclear Information System (INIS)

Zhao Jing; Zhu Neng; Wu Yong

2009-01-01

The building area in northern heating areas accounting for 70% of the total land area in China is 6,500,000,000 m 2 . The average heating energy consumption in northern China is 100-200% times more than developed countries in the same latitude. This paper introduced firstly the heat metering and energy efficiency retrofit background of existing residential buildings in northern heating areas of China organized by mohurd and MOF, and then put forward the total principle and contents of retrofit. Through analyzing some retrofit cases in Germany, Poland and China, some technological experiences were summarized and finally a technology line suitable for heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of China which involved retrofit for heat metering and temperature regulation of heating systems, heat balance of heat source and network, and building envelope was described to provide a systematic, scientific, technological guide for the retrofit projects of 0.15 billion m 2 in 'the Eleventh Five-Year Plan' period.

Optimisation of a Swedish district heating system with reduced heat demand due to energy efficiency measures in residential buildings

International Nuclear Information System (INIS)

Åberg, M.; Henning, D.

2011-01-01

The development towards more energy efficient buildings, as well as the expansion of district heating (DH) networks, is generally considered to reduce environmental impact. But the combined effect of these two progressions is more controversial. A reduced heat demand (HD) due to higher energy efficiency in buildings might hamper co-production of electricity and DH. In Sweden, co-produced electricity is normally considered to displace electricity from less efficient European condensing power plants. In this study, a potential HD reduction due to energy efficiency measures in the existing building stock in the Swedish city Linköping is calculated. The impact of HD reduction on heat and electricity production in the Linköping DH system is investigated by using the energy system optimisation model MODEST. Energy efficiency measures in buildings reduce seasonal HD variations. Model results show that HD reductions primarily decrease heat-only production. The electricity-to-heat output ratio for the system is increased for HD reductions up to 30%. Local and global CO 2 emissions are reduced. If co-produced electricity replaces electricity from coal-fired condensing power plants, a 20% HD reduction is optimal for decreasing global CO 2 emissions in the analysed DH system. - Highlights: ► A MODEST optimisation model of the Linköping district heating system is used. ► The impact of heat demand reduction on heat and electricity production is examined. ► Model results show that heat demand reductions decrease heat-only production. ► Local and global CO 2 emissions are reduced. ► The system electricity-to-heat output increases for reduced heat demand up to 30%.

Changes in heat load profile of typical Danish multi-storey buildings when energy-renovated and supplied with low-temperature district heating

DEFF Research Database (Denmark)

Harrestrup, Maria; Svendsen, Svend

2013-01-01

end-use savings are implemented in buildings concurrent with the application of low-temperature district heating (LTDH), the heat profiles of the buildings will change. Reducing peak loads is important, since this is the dimensioning foundation for future district heating systems. To avoid oversized...

Improved model for solar heating of buildings

OpenAIRE

Lie, Bernt

2015-01-01

A considerable future increase in the global energy use is expected, and the effects of energy conversion on the climate are already observed. Future energy conversion should thus be based on resources that have negligible climate effects; solar energy is perhaps the most important of such resources. The presented work builds on a previous complete model for solar heating of a house; here the aim to introduce ventilation heat recovery and improve on the hot water storage model. Ventilation he...

Demand side management for commercial buildings using an in line heat pump water heating methodology

International Nuclear Information System (INIS)

Rankin, Riaan; Rousseau, Pieter G.; Eldik, Martin van

2004-01-01

Most of the sanitary hot water used in South African buildings is heated by means of direct electrical resistance heaters. This is one of the major contributors to the undesirably high morning and afternoon peaks imposed on the national electricity supply grid. For this reason, water heating continues to be of concern to the electricity supplier, ESCOM. Previous studies, conducted by the Potchefstroom University for Christian Higher Education in South Africa, indicated that extensive application of the so called inline heat pump water heating methodology in commercial buildings could result in significant demand side management savings to ESKOM. Furthermore, impressive paybacks can be obtained by building owners who choose to implement the design methodology on existing or new systems. Currently, a few examples exist where the design methodology has been successfully implemented. These installations are monitored with a fully web centric monitoring system that allows 24 h access to data from each installation. Based on these preliminary results, a total peak demand reduction of 108 MW can be achieved, which represents 18% of the peak load reduction target set by ESKOM until the year 2015. This represents an avoided cost of approximately MR324 (ZAR) [Int J Energy Res 25(4) (1999) 2000]. Results based on actual data from the monitored installations shows a significant peak demand reduction for each installation. In one installation, a hotel with an occupancy of 220 people, the peak demand contribution of the hot water installation was reduced by 86%, realizing a 36% reduction in peak demand for the whole building. The savings incurred by the building owner also included significant energy consumption savings due to the superior energy efficiency of the heat pump water heater. The combined savings result in a conservatively calculated straight payback period of 12.5 months, with an internal rate of return of 98%. The actual cost of water heating is studied by

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…

An Innovative Use of Renewable Ground Heat for Insulation in Low Exergy Building Systems

Directory of Open Access Journals (Sweden)

Hansjürg Leibundgut

2012-08-01

Full Text Available Ground heat is a renewable resource that is readily available for buildings in cool climates, but its relatively low temperature requires the use of a heat pump to extract it for heating. We developed a system that uses low temperature ground heat directly in a building wall to reduce transmission heat losses. The Active Low Exergy Geothermal Insulation Systems (ALEGIS minimizes exergy demand and maximizes the use of renewable geothermal heat from the ground. A fluid is pumped into a small pipe network in an external layer of a wall construction that is linked to a ground heat source. This decouples the building from the outside temperature, therefore eliminating large peak demands and reducing the primary energy demand. Our steady-state analysis shows that at a design temperature of −10 °C the 6 cm thick active insulation system has equivalent performance to 11 cm of passive insulation. Our comparison of heating performance of a building with our active insulation system versus a building with static insulation of the same thickness shows a 15% reduction in annual electricity demand, and thus exergy input. We present an overview of the operation and analysis of our low exergy concept and its modeled performance.

ImBuild: Impact of building energy efficiency programs

Energy Technology Data Exchange (ETDEWEB)

Scott, M.J.; Hostick, D.J.; Belzer, D.B.

1998-04-01

As part of measuring the impact of government programs on improving the energy efficiency of the Nation`s building stock, the Department of Energy Office of Building Technology, State and Community Programs (BTS) is interested in assessing the economic impacts of its portfolio of programs, specifically the potential impact on national employment and income. The special-purpose version of the IMPLAN model used in this study is called ImBuild. In comparison with simple economic multiplier approaches, such as Department of Commerce RIMS 2 system, ImBuild allows for more complete and automated analysis of the economic impacts of energy efficiency investments in buildings. ImBuild is also easier to use than existing macroeconomic simulation models. The authors conducted an analysis of three sample BTS energy programs: the residential generator-absorber heat exchange gas heat pump (GAX heat pump), the low power sulfur lamp (LPSL) in residential and commercial applications, and the Building America program. The GAX heat pump would address the market for the high-efficiency residential combined heating and cooling systems. The LPSL would replace some highly efficient fluorescent commercial lighting. Building America seeks to improve the energy efficiency of new factory-built, modular, manufactured, and small-volume, site-built homes through use of systems engineering concepts and early incorporation of new products and processes, and by increasing the demand for more energy-efficient homes. The authors analyze a scenario for market penetration of each of these technologies devised for BTS programs reported in the BTS GPRA Metrics Estimates, FY99 Budget Request, December 19, 1997. 46 figs., 4 tabs.

Monitoring of Building Heating and Cooling Systems Based on Geothermal Heat Pump in Galicia (Spain

Directory of Open Access Journals (Sweden)

Franco D.

2012-10-01

Full Text Available In November 2009 was signed an agreement between Galicia’s Government and EnergyLab to develop a project related with the geothermal heatpumps (hereafter, GSHP technology. That project consisted in replacing the existing thermal equipment generators (diesel boilers and air-water heat pumps by GSHP systems in representative public buildings: two nursery schools, a university library, a health centre and a residential building. This new systems will reach the demands of existing heating, cooling and domestic hot water (hereafter, DHW. These buildings can serve as examples of energy and economic savings that can offer this technology. We will show detailed analysis of the GSHP facilities monitored, since the starting-up of them. Which includes: COP’s, EER’s, energy consumption, operating costs, operation hours of the system, economic and emissions comparative, geothermal exchange evolution graphs, environmental conditions evolution graphs (temperature and demands, etc. The results presented show an example of the important benefits of the GSHP technology and the significant savings that can offer its implementation for heating, cooling and DHW production.

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.

Model for Determining Geographical Distribution of Heat Saving Potentials in Danish Building Stock

Directory of Open Access Journals (Sweden)

Stefan Petrovic

2014-02-01

Full Text Available Since the global oil crisis in the 1970s, Denmark has followed a path towards energy independency by continuously improving its energy efficiency and energy conservation. Energy efficiency was mainly tackled by introducing a high number of combined heat and power plants in the system, while energy conservation was predominantly approached by implementing heat saving measures. Today, with the goal of 100% renewable energy within the power and heat sector by the year 2035, reductions in energy demand for space heating and the preparation of domestic hot water remain at the top of the agenda in Denmark. A highly detailed model for determining heat demand, possible heat savings and associated costs in the Danish building stock is presented. Both scheduled and energy-saving renovations until year 2030 have been analyzed. The highly detailed GIS-based heat atlas for Denmark is used as a container for storing data about physical properties for 2.5 million buildings in Denmark. Consequently, the results of the analysis can be represented on a single building level. Under the assumption that buildings with the most profitable heat savings are renovated first, the consequences of heat savings for the economy and energy system have been quantified and geographically referenced. The possibilities for further improvements of the model and the application to other geographical regions have been discussed.

Parametric Study on the Dynamic Heat Storage Capacity of Building Elements

DEFF Research Database (Denmark)

Artmann, Nikolai; Manz, H.; Heiselberg, Per

2007-01-01

as their interrelation. The potential of increasing thermal mass by using phase change materials (PCM) was estimated assuming increased thermal capacity. The results show a significant impact of the heat transfer coefficient on heat storage capacity, especially for thick, thermally heavy elements. The storage capacity...... of onedimensional heat conduction in a slab with convective boundary condition was applied to quantify the dynamic heat storage capacity of a particular building element. The impact of different parameters, such as slab thickness, material properties and the heat transfer coefficient was investigated, as well......In modern, extensively glazed office buildings, due to high solar and internal loads and increased comfort expectations, air conditioning systems are often used even in moderate and cold climates. Particularly in this case, passive cooling by night-time ventilation seems to offer considerable...

Possibility of heat recovery from gray water in residential building

Directory of Open Access Journals (Sweden)

Mazur Aleksandra

2017-12-01

Full Text Available Recovery of waste heat from gray water can be an interesting alternative to other energy saving systems in a building, including alternative energy sources. Mainly, due to a number of advantages including independence from weather conditions, small investment outlay, lack of user support, or a slight interference with the installation system. The purpose of this article is to present the financial effectiveness of installations which provide hot, usable water to a detached house, using a Drain Water Heat Recovery (DWHR system depending on the number of system users and the various combinations of bathing time in the shower, which has an influence on the daily warm water demand in each of the considered options. The economic analysis of the adopted installation variants is based on the Life Cycle Cost (LCC method, which is characterized by the fact that it also includes the operating costs in addition to the capital expenditure during the entire analysis period. For each case, the necessary devices were selected and the cost of their installation was estimated.

Possibility of heat recovery from gray water in residential building

Science.gov (United States)

Mazur, Aleksandra; Słyś, Daniel

2017-12-01

Recovery of waste heat from gray water can be an interesting alternative to other energy saving systems in a building, including alternative energy sources. Mainly, due to a number of advantages including independence from weather conditions, small investment outlay, lack of user support, or a slight interference with the installation system. The purpose of this article is to present the financial effectiveness of installations which provide hot, usable water to a detached house, using a Drain Water Heat Recovery (DWHR) system depending on the number of system users and the various combinations of bathing time in the shower, which has an influence on the daily warm water demand in each of the considered options. The economic analysis of the adopted installation variants is based on the Life Cycle Cost (LCC) method, which is characterized by the fact that it also includes the operating costs in addition to the capital expenditure during the entire analysis period. For each case, the necessary devices were selected and the cost of their installation was estimated.

Data for occupancy internal heat gain calculation in main building categories

Directory of Open Access Journals (Sweden)

Kaiser Ahmed

2017-12-01

Full Text Available Heat losses from occupant body by means of convection, radiation, vapor, and sweat are essential data for indoor climate and energy simulations. Heat losses depend on the metabolic activity and body surface area. Higher variations of body surface area of occupants are observed in day care centers, kinder gardens and schools compared to other building categories (Tables 2 and 3 and these variations need to be accounted, otherwise in these building categories heat gains, CO2 and humidity generation are overestimated. Indoor temperature, humidity level, air velocity, and clothing insulation have significant influences on dry and total heat losses from occupant body leading to typical values for summer and winter. The data presented in this article are related to the research article entitled Occupancy schedules for energy simulation in new prEN16798-1 and ISO/FDIS 17772-1 standards (Ahmed et al., 2017 [1]. Keywords: Body surface area, Metabolic rate, Dry heat loss, Total heat loss, Internal heat gain

New developments in illumination, heating and cooling technologies for energy-efficient buildings

International Nuclear Information System (INIS)

Han, H.J.; Jeon, Y.I.; Lim, S.H.; Kim, W.W.; Chen, K.

2010-01-01

This paper gives a concise review of new designs and developments of illumination, heating and air-conditioning systems and technologies for energy-efficient buildings. Important breakthroughs in these areas include high-efficiency and/or reduced cost solar system components, LED lamps, smart windows, computer-controlled illumination systems, compact combined heat-power generation systems, and so on. To take advantage of these new technologies, hybrid or cascade energy systems have been proposed and/or investigated. A survey of innovative architectural and building envelope designs that have the potential to considerably reduce the illumination and heating and cooling costs for office buildings and residential houses is also included in the review. In addition, new designs and ideas that can be easily implemented to improve the energy efficiency and/or reduce greenhouse gas emissions and environmental impacts of new or existing buildings are proposed and discussed.

Operational Planning of Low-Energy District Heating Systems Connected to Existing Buildings

DEFF Research Database (Denmark)

Tol, Hakan; Svendsen, Svend

2012-01-01

. The response of the radiator heating systems at different levels of supply temperature was used to form the operational planning of the low-energy DH system, which determined the design parameters of the low-energy DH network in terms of overall mass flow requirement and the return temperature from...... the buildings. Since the existing buildings were considered to be renovated to low-energy class, the operational planning was simultaneously modelled for both present high-demand and future low-demand situations of the same case area.......This article focuses on low-energy District Heating (DH) systems operating in low-temperatures such as 55°C in terms of supply and 25°C in terms of return in connection with existing buildings. Since the heat loss from the network has a significant impact in case of supplying heat to low...

Study of a two-pipe chilled beam system for both cooling and heating of office buildings

Energy Technology Data Exchange (ETDEWEB)

Norouzi, R. [Univ. of Boraes, Boraes (Sweden); Hultmark, G. [Lindab Comfort A/S, Farum (Denmark); Afshari, A. (ed.); Bergsoee, N.C. [Aalborg Univ.. Statens Byggeforskningsinstitut (SBi), Copenhagen (Denmark)

2013-05-15

The main aim of this master thesis was to investigate possibilities and limitations of a new system in active chilled beam application for office buildings. Lindab Comfort A/S pioneered the presented system. The new system use two-pipe system, instead of the conventional active chilled beam four-pipe system for heating and cooling purposes. The Two-Pipe System which is studied in this project use high temperature cooling and low temperature heating with water temperatures of 20 deg. C to 23 deg. C, available for free most of the year. The system can thus take advantage of renewable energy. It was anticipated that a Two-Pipe System application enables transfer of energy from warm spaces to cold spaces while return flows, from cooling and heating beams, are mixed. BSim software was chosen as a simulation tool to model a fictional office building and calculate heating and cooling loads of the building. Moreover, the effect of using outdoor air as a cooling energy source (free cooling) is investigated through five possible scenarios in both the four pipe system and the Two-Pipe System. The calculations served two purposes. Firstly, the effect of energy transfer in the Two-Pipe System were calculated and compared with the four pipe system. Secondly, free cooling effect was calculated in the Two-Pipe System and compared with the four pipe system. The simulation results showed that the energy transfer, as an inherent characteristic in the Two-Pipe System, is able to reduce up to 3 % of annual energy use compared to the four pipe system. Furthermore, different free cooling applications in the Two-Pipe System and the four pipe system respectively showed that the Two-Pipe System requires 7-15 % less total energy than the four pipe system in one year. In addition, the Two-Pipe System can save 18-57 % of annual cooling energy when compared to the four pipe system. (Author)

Low-energy district heating in energy-efficient building areas

International Nuclear Information System (INIS)

Dalla Rosa, A.; Christensen, J.E.

2011-01-01

This paper presents an innovative low-energy district heating (DH) concept based on low-temperature operation. The decreased heating demand from low-energy buildings affects the cost-effectiveness of traditionally-designed DH systems, so we carried out a case study of the annual energy performance of a low-energy network for low-energy houses in Denmark. We took into account the effect of human behaviour on energy demand, the effect of the number of buildings connected to the network, a socio-economic comparison with ground source heat pumps, and opportunities for the optimization of the network design, and operational temperature and pressure. In the north-European climate, we found that human behaviour can lead to 50% higher heating demand and 60% higher heating power than those anticipated in the reference values in the standard calculations for energy demand patterns in energy-efficient buildings. This considerable impact of human behaviour should clearly be included in energy simulations. We also showed that low-energy DH systems are robust systems that ensure security of supply for each customer in a cost-effective and environmentally friendly way in areas with linear heat density down to 0.20 MWh/(m year), and that the levelized cost of energy in low-energy DH supply is competitive with a scenario based on ground source heat pumps. The investment costs represent up to three quarters of the overall expenditure, over a time horizon of 30 years; so, the implementation of an energy system that fully relies on renewable energy needs substantial capital investment, but in the long term this is sustainable from the environmental and socio-economic points of view. Having demonstrated the value of the low-energy DH concept, we evaluated various possible designs with the aim of finding the optimal solution with regard to economic and energy efficiency issues. Here we showed the advantage of low supply and return temperatures, their effect on energy efficiency and that

A method of determining the thermal power demand of buildings connected to the district heating system with usage of heat accumulation

Directory of Open Access Journals (Sweden)

Turski Michał

2017-01-01

Full Text Available The paper presents a new method of determining the thermal power demand of buildings connected to the district heating system, which included the actual heat demand and the possibility of balancing the thermal power using the thermal storage capacity of district heating network and internal heat capacity of buildings. Moreover, the analysis of the effect of incidence of external air temperature and duration of episodes with the lowest outdoor temperatures on the thermal power demand of district heating system was conducted.

Simulation of temperature in office with building integrated heating and cooling system

DEFF Research Database (Denmark)

Weitzmann, Peter

2002-01-01

In this paper a numerical investigation of the thermal indoor environment has been performed for an office with building integrated hydronic heating and cooling system. Today office buildings are designed in such a way, and have such high internal heat loads and solar gains, that some kind...... of cooling is normally necessary for most of the year. Even in as cool climates as in the Nordic countries. The way the cooling is often achieved is through air conditioning. This can in many cases lead to sick building syndrome (SBS) symptoms, and furthermore it results in high energy consumption periods...... the temperature of the concrete to a level slightly below the desired room temperature, the concrete will work as an absorber for the excess heat in the office. This can significantly reduce the need for air conditioning, which will give both improved indoor climate and lower energy costs in the building...

Energy conservation. Purposeful regulation and control systems for gas infrared radiation heating

Energy Technology Data Exchange (ETDEWEB)

Reitsch, L [GoGaS Goch G.m.b.H. und Co., Dortmund (Germany, F.R.)

1978-01-01

Gas infrared radiators have been in use for a long time for heating large halls of trade and industrial buildings as well as sport centers. The success of this heating system is based mainly on considerably reduced energy consumption as against convective heating systems. However, the biggest energy savings can be achieved when heating systems of this kind are equipped with regulation and control systems which are adapted to the way the rooms are used. Solutions to problems are described and information is given for planning.

Structural observability analysis and EKF based parameter estimation of building heating models

Directory of Open Access Journals (Sweden)

D.W.U. Perera

2016-07-01

Full Text Available Research for enhanced energy-efficient buildings has been given much recognition in the recent years owing to their high energy consumptions. Increasing energy needs can be precisely controlled by practicing advanced controllers for building Heating, Ventilation, and Air-Conditioning (HVAC systems. Advanced controllers require a mathematical building heating model to operate, and these models need to be accurate and computationally efficient. One main concern associated with such models is the accurate estimation of the unknown model parameters. This paper presents the feasibility of implementing a simplified building heating model and the computation of physical parameters using an off-line approach. Structural observability analysis is conducted using graph-theoretic techniques to analyze the observability of the developed system model. Then Extended Kalman Filter (EKF algorithm is utilized for parameter estimates using the real measurements of a single-zone building. The simulation-based results confirm that even with a simple model, the EKF follows the state variables accurately. The predicted parameters vary depending on the inputs and disturbances.

Technology data characterizing water heating in commercial buildings: Application to end-use forecasting

Energy Technology Data Exchange (ETDEWEB)

Sezgen, O.; Koomey, J.G.

1995-12-01

Commercial-sector conservation analyses have traditionally focused on lighting and space conditioning because of their relatively-large shares of electricity and fuel consumption in commercial buildings. In this report we focus on water heating, which is one of the neglected end uses in the commercial sector. The share of the water-heating end use in commercial-sector electricity consumption is 3%, which corresponds to 0.3 quadrillion Btu (quads) of primary energy consumption. Water heating accounts for 15% of commercial-sector fuel use, which corresponds to 1.6 quads of primary energy consumption. Although smaller in absolute size than the savings associated with lighting and space conditioning, the potential cost-effective energy savings from water heaters are large enough in percentage terms to warrant closer attention. In addition, water heating is much more important in particular building types than in the commercial sector as a whole. Fuel consumption for water heating is highest in lodging establishments, hospitals, and restaurants (0.27, 0.22, and 0.19 quads, respectively); water heating`s share of fuel consumption for these building types is 35%, 18% and 32%, respectively. At the Lawrence Berkeley National Laboratory, we have developed and refined a base-year data set characterizing water heating technologies in commercial buildings as well as a modeling framework. We present the data and modeling framework in this report. The present commercial floorstock is characterized in terms of water heating requirements and technology saturations. Cost-efficiency data for water heating technologies are also developed. These data are intended to support models used for forecasting energy use of water heating in the commercial sector.

Potential heat savings during ongoing renovation of buildings until 2050

DEFF Research Database (Denmark)

Wittchen, Kim Bjarne; Kragh, Jesper; Aggerholm, Søren

information about insulation level, building component areas, i.e. roofs, external walls, floors and windows/doors, per unit area (gross heated floor area). The report is made for the Danish Energy Agency and targeted the Danish building industry, the agency itself and political decision makers in preparation...

Possibilities of heat energy recovery from greywater systems

Science.gov (United States)

Niewitecka, Kaja

2018-02-01

Waste water contains a large amount of heat energy which is irretrievably lost, so it is worth thinking about the possibilities of its recovery. It is estimated that in a residential building with full sanitary fittings, about 70% of the total tap water supplied is discharged as greywater and could be reused. The subject of the work is the opportunity to reuse waste water as an alternative source of heat for buildings. For this purpose, the design of heat exchangers used in the process of greywater heat recovery in indoor sewage systems, public buildings as well as in industrial plants has been reviewed. The possibility of recovering heat from waste water transported in outdoor sewage systems was also taken into consideration. An exemplary waste water heat recovery system was proposed, and the amount of heat that could be obtained using a greywater heat recovery system in a residential building was presented. The work shows that greywater heat recovery systems allow for significant savings in preheating hot tap water, and the rate of cost reimbursement depends on the purpose of the building and the type of installation. At the same time, the work shows that one should adjust the construction solutions of heat exchangers and indoor installations in buildings to the quality of the medium flowing, which is greywater.

Procedure for identifying models for the heat dynamics of buildings

DEFF Research Database (Denmark)

Bacher, Peder; Madsen, Henrik

This report describes a new method for obtaining detailed information about the heat dynamics of a building using frequent reading of the heat consumption. Such a procedure is considered to be of uttermost importance as a key procedure for using readings from smart meters, which is expected...

Hydronic Heating Retrofits for Low-Rise Multifamily Buildings: Boiler Control Replacement and Monitoring

Energy Technology Data Exchange (ETDEWEB)

Dentz, J.; Henderson, H.; Varshney, K.

2014-09-01

The ARIES Collaborative, a U.S. Department of Energy Building America research team, partnered with NeighborWorks America affiliate Homeowners' Rehab Inc. (HRI) of Cambridge, Massachusetts, to study improvements to the central hydronic heating system in one of the nonprofit's housing developments. The heating controls in the three-building, 42-unit Columbia Cambridge Alliance for Spanish Tenants housing development were upgraded. Fuel use in the development was excessive compared to similar properties. A poorly insulated thermal envelope contributed to high energy bills, but adding wall insulation was not cost-effective or practical. The more cost-effective option was improving heating system efficiency. Efficient operation of the heating system faced several obstacles, including inflexible boiler controls and failed thermostatic radiator valves. Boiler controls were replaced with systems that offer temperature setbacks and one that controls heat based on apartment temperature in addition to outdoor temperature. Utility bill analysis shows that post-retrofit weather-normalized heating energy use was reduced by 10%-31% (average of 19%). Indoor temperature cutoff reduced boiler runtime (and therefore heating fuel consumption) by 28% in the one building in which it was implemented. Nearly all savings were obtained during night which had a lower indoor temperature cut off (68 degrees F) than day (73 degrees F). This implies that the outdoor reset curve was appropriately adjusted for this building for daytime operation. Nighttime setback of heating system supply water temperature had no discernable impact on boiler runtime or gas bills.

Building Space Heating with a Solar-Assisted Heat Pump Using Roof-Integrated Solar Collectors

Directory of Open Access Journals (Sweden)

Zhiyong Yang

2011-03-01

Full Text Available A solar assisted heat pump (SAHP system was designed by using a roof-integrated solar collector as the evaporator, and then it was demonstrated to provide space heating for a villa in Tianjin, China. A building energy simulation tool was used to predict the space heating load and a three dimensional theoretical model was established to analyze the heat collection performance of the solar roof collector. A floor radiant heating unit was used to decrease the energy demand. The measurement results during the winter test period show that the system can provide a comfortable living space in winter, when the room temperature averaged 18.9 °C. The average COP of the heat pump system is 2.97 and with a maximum around 4.16.

Hydraulic Control Method for Heating Systems of High-Rise Buildings

Science.gov (United States)

Makarov, D.; Chernenkov, V.; Likhachev, I.

2017-11-01

The following article reflects the ideas of possibility to increase energy efficiency of heating systems in high-rise buildings. The article also includes the principle ways of high-rise building heating systems operation as well as traditional engineering decisions aimed at the elimination of the increased pressure effect in heaters. The main disadvantages of such decisions are also presented for the reader. Moreover, the article offers the way of operation for the above-mentioned systems together with the equipment that implements this operation. An economic impact from such energy-saving technology application has been also evaluated.

Analyzing Design Heating Loads in Superinsulated Buildings

Energy Technology Data Exchange (ETDEWEB)

Arena, Lois [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

2015-06-01

Super-insulated homes offer many benefits including improved comfort, reduced exterior noise penetration, lower energy bills, and the ability to withstand power and fuel outages under much more comfortable conditions than a typical home. While these homes aren't necessarily constructed with excessive mass in the form of concrete floors and walls, the amount of insulation and the increase in the thickness of the building envelope can lead to a mass effect, resulting in the structures ability to store much more heat than a code built home. This results in a very low thermal inertia making the building much less sensitive to drastic temperature swings thereby decreasing the peak heating load demand. During the winter of 2013/2014, CARB monitored the energy use of three homes in climate zone 6 in an attempt to evaluate the accuracy of two different mechanical system sizing methods for low load homes. Based on the results, it is recommended that internal and solar gains be included and some credit for thermal inertia be used in sizing calculations for super insulated homes.

Influence of staircase ventilation state on the airflow and heat transfer of the heated room on the middle floor of high rise building

International Nuclear Information System (INIS)

Shi, W.X.; Ji, J.; Sun, J.H.; Lo, S.M.; Li, L.J.; Yuan, X.Y.

2014-01-01

Highlights: • Experiments are conducted in a scaled building model. • The flow and heat transfer in the heated room are investigated. • The staircase ventilation state influence on the heated room. • The results are useful to understand the safety and energy efficiency of building. - Abstract: Safety and energy efficiency of high rise buildings have attracted public attention in recent decades. In this paper, a set of experiments was conducted in a scaled building model with 12 floors to study the influence of the staircase ventilation state on the flow and heat transfer of the heated room on the middle floor. The airflow, room temperature and fuel burning rate were investigated. It is found that when the window above the heated room is opened, the vents state below the heated room has a significant effect on the airflow and heat transfer in the heated room. When the vents below the heated room are closed, the single-directional air flows into the heated room owing to the stronger stack effect. And the flame tilt angle is larger and the upper hot smoke temperature in the heated room is low. However, when the windows above the heated room are closed, the vents state below the heated room has little influence on the airflow and heat transfer in the heated room. And, there is two-directional air flowing through the door of the heated room The burning rate of heat source is also affected by the staircase ventilation state, and the variation trend varies with the opened window position and pool size

Development concept concerning the utilization of district heating for cooling of buildings; Udviklingskoncept vedroerende anvendelse af fjernvarme til koeling

Energy Technology Data Exchange (ETDEWEB)

Andersson, L.; Minds, G.; Hansen, K.E.; Hammer, F.

1998-03-01

The main purpose of the project was to develop a concept for cooling of buildings by means of district heating based on Danish conditions. Heat operated cooling plants placed at the individual consumers or in local cooling stations, from where cold water is distributed in small networks to a limited number of consumers, are the main elements of the concept. Basically it should be possible to use the technology in connection with the district heating systems spread all over the country, systems which are characterised by rather low temperatures - typically between 70 deg. and 90 deg. C in the supply pipes and about 40-50 deg. C in the return pipes. In transmission networks the level is often 10-20 deg. C higher. The cooling is mainly to be used for air-conditioning of shopping centres, office buildings, computer plants, hospitals, nursing homes etc. The project is based on the conditions in Hoeje Taastrup, which is a relatively new and open city area with a rather big concentration of buildings which already need cooling. At the moment this demand is covered by individual electrically operated compressors. Models of heat based cooling plants are set up and compared to the present compressor based systems with respect to technology, energy, economy and environmental conditions. The results are generalised, thus they will be relevant to other Danish towns supplied by district heating. However, the possibilities of cooling based on natural gas from small scale combined heat and power have not been discussed at all. (EG)

Integration of a magnetocaloric heat pump in a low-energy residential building

DEFF Research Database (Denmark)

Johra, Hicham

2018-01-01

The EnovHeat project aims at developing an innovative heat pump system based on the magnetocaloric effect and active magnetic regenerator technology to provide for the heating needs of a single family house in Denmark. Unlike vapor-compression devices, magnetocaloric heat pumps use the reversible...... heat pump can deliver 2600 W of heating power with an appreciable average seasonal system COP of 3.93. On variable part-load operation with a simple fluid flow controller, it can heat up an entire house with an average seasonal system COP of 1.84....... magnetocaloric effect of a solid refrigerant to build a cooling/heating cycle. It has the potential for high coefficient of performance, more silent operation and efficient part-load control. After presenting the operation principles of the magnetocaloric device and the different models used in the current...... numerical study, this article demonstrates for the first time the possibility to utilize this novel heat pump in a building. This device can be integrated in a single hydronic loop including a ground source heat exchanger and a radiant under-floor heating system. At maximum capacity, this magnetocaloric...

Numerical simulation of heat transfer through the building facades of buildings located in the city of Bechar

Directory of Open Access Journals (Sweden)

A Missoum

2016-12-01

Full Text Available This study deals with the transient heat transfer in a multi-layered building wall through the facades of the buildings located in the city of Bechar (south-west Algeria. The physical model is presented to find the variation of the transient temperature in these structures and the heat flux through these elements, which depends on the air temperature of the inner surface and the instantaneous climatic conditions of the air outside. Comsol Multiphysics based on the finite element method is designed to perform numerical simulations. The measured hourly ambient air temperatures and the solar radiation flux on the horizontal surface for the city of Bechar Algeria are using during the hottest period (July 2015, and also using the properties Thermodynamics of each component of the structure. The validation of the analytical model with this simulation is verified in this document. The calculations carried out for different multilayer building walls which are commonly used in the south of Algeria to determine the thermal behavior of these structures and the influence of radiation heat flux on these elements.

Building occupancy diversity and HVAC (heating, ventilation, and air conditioning) system energy efficiency

International Nuclear Information System (INIS)

Yang, Zheng; Ghahramani, Ali; Becerik-Gerber, Burcin

2016-01-01

Approximately forty percent of total building energy consumption is attributed to HVAC (heating, ventilation, and air conditioning) systems that aim to maintain healthy and comfortable indoor environments. An HVAC system is a network with several subsystems, and there exist heat transfer and balance among the zones of a building, as well as heat gains and losses through a building's envelope. Diverse occupancy (diversity in terms of when and how occupants occupy a building) in spaces could result in increase of loads that are not actual demands for an HVAC system, leading into inefficiencies. This paper introduces a framework to quantitatively evaluate the energy implications of occupancy diversity at the building level, where building information modeling is integrated to provide building geometries, HVAC system layouts, and spatial information as inputs for computing potential energy implications if occupancy diversity were to be eliminated. An agglomerate hierarchical clustering-based iterative evaluation algorithm is designed for iteratively eliminating occupancy diversity. Whole building energy simulations for a real-world building, as well as virtual reference buildings demonstrate that the proposed framework could effectively quantify the HVAC system energy efficiency affected by occupancy diversity and the framework is generalizable to different building geometries, layouts, and occupancy diversities. - Highlights: • Analyze relationships between occupancy diversity and HVAC energy efficiency. • Integrate BIM for quantifying energy implications of occupancy diversity. • Demonstrate the effectiveness and generalizability of iterative evaluation algorithm. • Improve agglomerative hierarchical clustering process using heap data structure.

Study of thermosiphon and radiant panel passive heating systems for metal buildings

Energy Technology Data Exchange (ETDEWEB)

Biehl, F.A.; Schnurr, N.M.; Wray, W.O.

1983-01-01

A study of passive-heating systems appropriate for use on metal buildings is being conducted at Los Alamos National Laboratory for the Naval Civil Engineering Laboratory, Port Hueneme, California. The systems selected for study were chosen on the basis of their appropriateness for retrofit applications, although they are also suitable for new construction: simple radiant panels that communicate directly with the building interior and a backflow thermosiphon that provides heat indirectly.

Fort Carson Building 1860 Biomass Heating Analysis Report

Energy Technology Data Exchange (ETDEWEB)

Hunsberger, Randolph [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tomberlin, Gregg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gaul, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-09-01

As part of the Army Net-Zero Energy Installation program, the Fort Carson Army Base requested that NREL evaluate the feasibility of adding a biomass boiler to the district heating system served by Building 1860. We have also developed an Excel-spreadsheet-based decision support tool--specific to the historic loads served by Building 1860--with which users can perform what-if analysis on gas costs, biomass costs, and other parameters. For economic reasons, we do not recommend adding a biomass system at this time.

Building with integral solar-heat storage--Starkville, Mississippi

Science.gov (United States)

1981-01-01

Column supporting roof also houses rock-storage bin of solar-energy system supplying more than half building space heating load. Conventional heaters supply hot water. Since bin is deeper and narrower than normal, individual pebble size was increased to keep airflow resistance at minimum.

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.

A model predictive framework of Ground Source Heat Pump coupled with Aquifer Thermal Energy Storage System in heating and cooling equipment of a building

NARCIS (Netherlands)

Rostampour Samarin, V.; Bloemendal, J.M.; Keviczky, T.

2017-01-01

This paper presents a complete model of a building heating and cooling equipment and a ground source heat pump (GSHP) coupled with an aquifer thermal energy storage (ATES) system. This model contains detailed
mathematical representations of building thermal dynamics, ATES system dynamics, heat

Data for occupancy internal heat gain calculation in main building categories

DEFF Research Database (Denmark)

Ahmed, Kaiser; Kurnitski, Jarek; Olesen, Bjarne W.

2017-01-01

, kinder gardens and schools compared to other building categories (Tables 2 and 3) and these variations need to be accounted, otherwise in these building categories heat gains, CO2 and humidity generation are overestimated. Indoor temperature, humidity level, air velocity, and clothing insulation have...

Modeling of heat and mass transfer in lateritic building envelopes

International Nuclear Information System (INIS)

Meukam, Pierre

2004-10-01

The aim of the present work is to investigate the behavior of building envelopes made of local lateritic soil bricks subjected to different climatic conditions. The analysis is developed for the prediction of the temperature, relative humidity and water content behavior within the walls. The building envelopes studied in this work consist of lateritic soil bricks with incorporation of natural pozzolan or sawdust in order to obtain small thermal conductivity and low-density materials, and limit the heat transfer between the atmospheric climate and the inside environment. In order to describe coupled heat and moisture transfer in wet porous materials, the coupled equations were solved by the introduction of diffusion coefficients. A numerical model HMtrans, developed for prediction of beat and moisture transfer in multi-layered building components, was used to simulate the temperature, water content and relative humidity profiles within the building envelopes. The results allow the prediction of the duration of the exposed building walls to the local weather conditions. They show that for any of three climatic conditions considered, relative humidity and water content do not exceed 87% and 5% respectively. There is therefore minimum possibility of water condensation in the materials studied. The durability of building envelopes made of lateritic soil bricks with incorporation of natural pozzolan or sawdust is not strongly affected by the climatic conditions in tropical and equatorial regions. (author)

Modelling energy savings in the Danish building sector combined with internalisation of health related externalities in a heat and power system optimisation model

DEFF Research Database (Denmark)

Zvingilaite, Erika

2013-01-01

. Furthermore, the results suggest that changes in the energy generation sector are the prime driver behind the reduction of environmental externalities of energy. Heat savings in buildings play only a small role under model assumptions. © 2012Elsevier Ltd. All rights reserved.......A substantial untapped energy saving potential rests in the building sector and is expected to play an important role in achieving reduction of environmental impacts of energy. In order to utilise this potential, effective policy measures need to be adopted to remove the existing barriers...... and create incentives. For that purpose, the cost effective energy saving options together with an optimal level of savings and expected environmental benefits have to be identified. The paper reports on a study that analyses these questions by including heat-saving measures in buildings into an energy...

Assets of geothermal energy for buildings: heating, cooling and domestic hot water

International Nuclear Information System (INIS)

2016-01-01

This publication first proposes a brief overview on the status, context and perspectives of geothermal energy in France by evoking the great number of heat pumps installed during the last decades and the choice made by public and private clients for this source of heating and cooling. While indicating how geothermal energy intervenes during a building project, this publication outlines that this energy is discrete and renewable, and that its technology is proven. Some examples are then evoked: use of geothermal energy for a public building in Saint-Malo, for estate projects near Paris, for a shopping centre in Roissy, and for office buildings

Dynamic Heat Production Modeling for Life Cycle Assessment of Insulation in Danish Residential Buildings

DEFF Research Database (Denmark)

Sohn, Joshua L.; Kalbar, Pradip; Birkved, Morten

2017-01-01

insulation in a Danish single-family detached home. This single family house, is based on averages of current Danish construction practices with building heat losses estimated using Be10. To simulate a changing district heating grid mix, heat supply fuel sources are modeled according to Danish energy mix...... for space heating without insulation over the lifespan of a building. When the energy sources for insulation production are similar to the energy mix that supplies heat, this logic is valid to very high level of insulation. However, in Denmark, as well as many other countries this assumption is becoming...... increasingly incorrect. Given the generally long service life of buildings, the significance of future energy mixes, which are expected/intended to have a smaller environmental impact, can be great. In this paper, a reference house is used to assess the life cycle environmental impacts of mineral wool...

Innovation in Management of Primary School Construction: Multi-Purpose Primary School Buildings in Bangladesh. Educational Building Report 18.

Science.gov (United States)

Constantinos, Fecadu

This report deals with school building construction utilizing technology carried out by the Lutheran World Service/Rangpur Dinajpur Rehabilitation Service in Bangladesh. The purpose was to develop an alternative design for primary school constructions. The design, construction, and multipurpose use of the school buildings are described. Appended…

Simultaneous heat and moisture transfer in soils combined with building simulation

Energy Technology Data Exchange (ETDEWEB)

Santos, G. H. dos; Mendes, N. [Pontifical Catholic University of Parana, PUCPR/CCET, Thermal Systems Laboratory (LST), Curitiba (Brazil)

2006-07-01

In order to precisely predict ground heat transfer, room air temperature and humidity, a combined model has been developed and conceived to calculate both the coupled heat and moisture transfer in soil and floor and the psychrometrics condition of indoor air. The present methodology for the soil is based on the theory of Philip and De Vries, using variable thermophysical properties for different materials. The governing equations were discretized using the finite-volume method and a three-dimensional model for describing the physical phenomena of heat and mass transfer in unsaturated moist porous soils and floor. Additionally, a lumped transient approach for a building room and a finite-volume multi-layer model for the building envelope have been developed to integrate with the soil model. Results are presented in terms of temperature, humidity and heat flux at the interface between room air and the floor, showing the importance of the approach presented and the model robustness for long-term simulations with a high time step. (author)

Experimental Analysis of a Heat Cost Allocation Method for Apartment Buildings

Directory of Open Access Journals (Sweden)

Fabio Saba

2017-03-01

Full Text Available The correct estimate of individual thermal energy consumptions, and consequently, a fair heat cost allocation among the residents of apartment buildings with centralized heating systems, represents an important driving force towards energy saving, energy efficiency and the reduction of pollutant emissions. Nowadays, in those contexts where direct heat meters cannot be used because of the layout of the hot water distribution system, electronic Heat Cost Allocators (HCAs have the highest market share for the assessment of individual thermal energy consumptions. The uncertainty associated with the parameterization of heat cost allocation devices and the installation effects arising in real applications can negatively affect the accuracy of these devices, as far as the estimation of the individual fractions of thermal energy consumption is concerned. This work deals with the experimental analysis of a novel heat cost allocation method for apartment buildings and its comparison with conventional HCAs. The method allows the indirect estimation of the thermal energy exchanged by water radiators without the need for surface temperature measurements, reducing some of the drawbacks associated with the on-site installation. The experimental analysis was carried out in a full-scale central heating system test facility available at the Italian National Metrology Institute (INRIM and characterized by SI-traceable direct heat meters installed on each water radiator.

Building Fit-for-Purpose Land Administration Systems

DEFF Research Database (Denmark)

Enemark, Stig; Bell, Keith; Lemmen, Christiaan

2014-01-01

Arguably sound land governance is the key to achieve sustainable development and to support the global agenda set by adoption of the Millennium Development Goals (MDGs). The operational component of land governance is the country specific land administration systems dealing with the four key...... functions of land tenure, land value, land, and land development. Land administration systems - whether highly advanced or very basic – require a land parcel framework to operate. Building such a land parcel framework – showing the way land is divided into parcels and plots for specific use and possession...... no. 60 on “Fit-for-Purpose Land Administration”. It is argued that the land parcel framework should be developed using a flexible and fit-for-purpose approach rather than being guided by costly field survey procedures or over-engineered technology solutions. When considering the resources...

Energy system investment model incorporating heat pumps with thermal storage in buildings and buffer tanks

International Nuclear Information System (INIS)

Hedegaard, Karsten; Balyk, Olexandr

2013-01-01

Individual compression heat pumps constitute a potentially valuable resource in supporting wind power integration due to their economic competitiveness and possibilities for flexible operation. When analysing the system benefits of flexible heat pump operation, effects on investments should be taken into account. In this study, we present a model that facilitates analysing individual heat pumps and complementing heat storages in integration with the energy system, while optimising both investments and operation. The model incorporates thermal building dynamics and covers various heat storage options: passive heat storage in the building structure via radiator heating, active heat storage in concrete floors via floor heating, and use of thermal storage tanks for space heating and hot water. It is shown that the model is well qualified for analysing possibilities and system benefits of operating heat pumps flexibly. This includes prioritising heat pump operation for hours with low marginal electricity production costs, and peak load shaving resulting in a reduced need for peak and reserve capacity investments. - Highlights: • Model optimising heat pumps and heat storages in integration with the energy system. • Optimisation of both energy system investments and operation. • Heat storage in building structure and thermal storage tanks included. • Model well qualified for analysing system benefits of flexible heat pump operation. • Covers peak load shaving and operation prioritised for low electricity prices

Experimental investigations of heat transfer in thermo active building systems in combination with suspended ceilings

DEFF Research Database (Denmark)

Alvarez, Maria Alonso; Hviid, Christian Anker; Weitzmann, Peter

2014-01-01

buildings to cover acoustic requirements hinders the use of TABS. To measure the reduction of the heat capacity, several experiments are performed in a room equipped with TABS in the upper deck and mixing ventilation. The heat transfer is measured for different suspended ceiling covering percentages...... that the ventilation rate has a high influence on the convective heat capacity. When the ventilation rate is increased from 1.7 h-1 to 2.9 h-1, the heat transfer coefficient increases up to 16% for the same occupancy and suspended ceiling layout.......Thermo Active Building Systems (TABS), described as radiant heating or cooling systems with pipes embedded in the building structure, represent a sustainable alternative to replace conventional systems by using source temperatures close to room temperatures. The use of suspended ceiling in office...

Geospatial Analysis of the Building Heat Demand and Distribution Losses in a District Heating Network

Directory of Open Access Journals (Sweden)

Tobias Törnros

2016-11-01

Full Text Available The district heating (DH demand of various systems has been simulated in several studies. Most studies focus on the temporal aspects rather than the spatial component. In this study, the DH demand for a medium-sized DH network in a city in southern Germany is simulated and analyzed in a spatially explicit approach. Initially, buildings are geo-located and attributes obtained from various sources including building type, ground area, and number of stories are merged. Thereafter, the annual primary energy demand for heating and domestic hot water is calculated for individual buildings. Subsequently, the energy demand is aggregated on the segment level of an existing DH network and the water flow is routed through the system. The simulation results show that the distribution losses are overall the highest at the end segments (given in percentage terms. However, centrally located pipes with a low throughflow are also simulated to have high losses. The spatial analyses are not only useful when addressing the current demand. Based on a scenario taking into account the refurbishment of buildings and a decentralization of energy production, the future demand was also addressed. Due to lower demand, the distribution losses given in percentage increase under such conditions.

Design of energy-efficient buildings using interaction between Building Simulation Programme and Energy Supply Simulations for District Heating

DEFF Research Database (Denmark)

Christensen, Jørgen Erik; Dalla Rosa, Alessandro; Nagla, Inese

potential of the energy saving in the society it is very important to address the decisive involvement of the end-users. The human behaviour is the factor that affects the most the energy use in low-energy buildings and should be included in energy simulations. The results can then be linked to programs...... the implementation of C02 neutral communities. A link between a dynamic energy simulation program for buildings and a simulation program for district heating networks is demonstrated. The results of the investigation give an example of how to analyze a community and make recommendations for applying the low...... in a cost-effective way in areas with linear heat densities down to 0.20 MWh/(m.year). Even in cases where the user behaviour is not optimal, the system is able to deliver heat to each customer. The low-energy district heating concept could be strategic for reaching ambitious energy and climate targets...

Power performance of the general-purpose heat source radioisotope thermoelectric generator

International Nuclear Information System (INIS)

Bennett, G.L.; Lombardo, J.J.; Rock, B.J.

1986-01-01

The General-Purpose Heat Source Radioisotope Thermoelectric Generator (GRHS-RTG) has been developed under the sponsorship of the Department of Energy (DOE) to provide electrical power for the National Aeronautics and Space Administration (NASA) Galileo mission to Jupiter and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun. A total of five nuclear-heated generators and one electrically heated generator have been built and tested, proving out the design concept and meeting the specification requirements. The GPHS-RTG design is built upon the successful-technology used in the RTGs flown on the two NASA Voyager spacecraft and two US Air Force communications satellites. THe GPHS-RTG converts about 4400 W(t) from the nuclear heat source into at least 285 W(e) at beginning of mission (BOM). The GPHS-RTG consists of two major components: the General-Purpose Heat Source (GPHS) and the Converter. A conceptual drawing of the GPHs-RTG is presented and its design and performance are described

Spatial–Temporal Analysis of the Heat and Electricity Demand of the Swiss Building Stock

Directory of Open Access Journals (Sweden)

Stefan Schneider

2017-08-01

Full Text Available In 2015, space heating and domestic hot water production accounted for around 40% of the Swiss final energy consumption. Reaching the goals of the 2050 energy strategy will require significantly reducing this share despite the growing building stock. Renewables are numerous but subject to spatial–temporal constraints. Territorial planning of energy distribution systems enabling the integration of renewables requires having a spatial–temporal characterization of the energy demand. This paper presents two bottom-up statistical extrapolation models for the estimation of the geo-dependent heat and electricity demand of the Swiss building stock. The heat demand is estimated by means of a statistical bottom-up model applied at the building level. At the municipality level, the electricity load curve is estimated by combining socio-economic indicators with average consumption per activity and/or electric device. This approach also allows to break down the estimated electricity demand according to activity type (e.g., households, various industry, and service activities and appliance type (e.g., lighting, motor force, fridges. The total estimated aggregated demand is 94 TWh for heat and 58 TWh for electricity, which represent a deviation of 2.9 and 0.5%, respectively compared to the national energy consumption statistics. In addition, comparisons between estimated and measured electric load curves are done to validate the proposed approach. Finally, these models are used to build a geo-referred database of heat and electricity demand for the entire Swiss territory. As an application of the heat demand model, a realistic saving potential is estimated for the existing building stock; this potential could be achieved through by a deep retrofit program. One advantage of the statistical bottom-up model approach is that it allows to simulate a building stock that replicates the diversity of building demand. This point is important in order to

Experimental Study and Modeling of Ground-Source Heat Pumps with Combi-Storage in Buildings

Directory of Open Access Journals (Sweden)

Wessam El-Baz

2018-05-01

Full Text Available There is a continuous growth of heat pump installations in residential buildings in Germany. The heat pumps are not only used for space heating and domestic hot water consumption but also to offer flexibility to the grid. The high coefficient of performance and the low cost of heat storages made the heat pumps one of the optimal candidates for the power to heat applications. Thus, several questions are raised about the optimal integration and control of heat pump system with buffer storages to maximize its operation efficiency and minimize the operation costs. In this paper, an experimental investigation is performed to study the performance of a ground source heat pump (GSHP with a combi-storage under several configurations and control factors. The experiments were performed on an innovative modular testbed that is capable of emulating a ground source to provide the heat pump with different temperature levels at different times of the day. Moreover, it can emulate the different building loads such as the space heating load and the domestic hot water consumption in real-time. The data gathered from the testbed and different experimental studies were used to develop a simulation model based on Modelica that can accurately simulate the dynamics of a GSHP in a building. The model was validated based on different metrics. Energetically, the difference between the developed model and the measured values was only 3% and 4% for the heat generation and electricity consumption, respectively.

SOME FEATURES OF THE POWER SUPPLY OF RESIDENTIAL BUILDINGS DURING THE HEATING SEASON

Directory of Open Access Journals (Sweden)

S. N. Osipov

2017-01-01

Full Text Available A large proportion of consumption of different types of energy by the residential sector, especially in the heating period, makes the energy efficiency of buildings without considering the loss of fuel with a significant reduction in hourly load on the generators, especially at night, already insufficient for real energy savings. Therefore in Belarus, in order to attract the consumer, electricity tariff for heating at night hours (from 11 p.m. to 6.00 a.m. is three times cheaper than at any other time. Significant increase of the electricity consumption of at night could be achieved by using heat accumulators for heating and hot water supply to the residential sector. Particularly effective are water accumulators of heat and accumulators of underfloor heating that enable to use a coolant with a temperature of 40 оC and to increase the useful supply of heat. The use of heat accumulators for daily heating, ventilation and hot water supply of buildings significantly reduces the cost of creating the infrastructure of the territory under construction by eliminating the necessity of running the distribution network of heat or gas supply. The use of the heat accumulators is necessary due to the increase of the time-weighted average outdoor temperature. The mentioned increase in the City of Minsk in the heating season is of about 0.1 °C per year in average, and as for the last 20 years, the increase has led to a reduction of the required heat load on the premises by about 10 %. Research and project work on choosing the most effective options for the arrangement and use the heat accumulators in buildings of the various functions ought to be fulfilled in order to make the application of heat accumulators successful. In this respect civil and power engineers as well as operators should work together so to determine the chronological, technical and economic conditions of charging and use of heat accumulators.

Experimental building with new types of building envelope structures. Part 1: Structures/systems. Building system: Brick walls; Forsoegshus med nye typer klimaskaermskonstruktioner. Del 1: Konstruktioner/systemer - Byggesystem: Fuldmuret

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The house described in this report is one of several experimental houses forming part of the project 'Experimental buildings with new types of building envelope structures'. One purpose of the project is to demonstrate that it is possible to build typical single-family houses with an energy consumption that meets expected increased building regulations. Furthermore, it is important that the houses can be made securely as regards construction technology and within reasonable financial limits. Thus, the purpose is also to contribute to strengthen the development of improved building envelope structures. Another purpose is to carry out detailed measurements of energy consumption in order to validate thermal performance of future building envelope structures. The report describes the constructive design and energy systems of the house plus heat loss calculations and expected energy consumption. (BA)

Modeling of Heat Transfer in Rooms in the Modelica "Buildings" Library

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zuo, Wangda [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nouidui, Thierry Stephane [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2011-11-01

This paper describes the implementation of the room heat transfer model in the free open-source Modelica \\Buildings" library. The model can be used as a single room or to compose a multizone building model. We discuss how the model is decomposed into submodels for the individual heat transfer phenomena. We also discuss the main physical assumptions. The room model can be parameterized to use different modeling assumptions, leading to linear or non-linear differential algebraic systems of equations. We present numerical experiments that show how these assumptions affect computing time and accuracy for selected cases of the ANSI/ASHRAE Standard 140- 2007 envelop validation tests.

Annual performance of building-integrated photovoltaic/water-heating system for warm climate application

International Nuclear Information System (INIS)

Chow, T.T.; Chan, A.L.S.; Fong, K.F.; Lin, Z.; He, W.; Ji, J.

2009-01-01

A building-integrated photovoltaic/water-heating (BiPVW) system is able to generate higher energy output per unit collector area than the conventional solar systems. Through computer simulation with energy models developed for this integrative solar system in Hong Kong, the results showed that the photovoltaic/water-heating (PVW) system has economic advantages over the conventional photovoltaic (PV) installation. The system thermal performance under natural water circulation was found better than the pump-circulation mode. For a specific BiPVW system at a vertical wall of a fully air-conditioned building and with collectors equipped with flat-box-type thermal absorber and polycrystalline silicon cells, the year-round thermal and cell conversion efficiencies were found respectively 37.5% and 9.39% under typical Hong Kong weather conditions. The overall heat transmission through the PVW wall is reduced to 38% of the normal building facade. When serving as a water pre-heating system, the economical payback period was estimated around 14 years. This greatly enhances the PV market opportunities. (author)

Innovative Hybrid CHP systems for high temperature heating plant in existing buildings

NARCIS (Netherlands)

de Santoli, Livio; Lo Basso, Gianluigi; Nastasi, B.; d’Ambrosio Alfano, Francesca R.; Mazzarella and Piercarlo, Livio

2017-01-01

This paper deals with the potential role of new hybrid CHP systems application providing both electricity and heat which are compatible with the building architectural and landscape limitations. In detail, three different plant layout options for high temperature heat production along with the

Analysis of heat source selection for residential buildings in rural areas

OpenAIRE

Szul Tomasz

2018-01-01

The research aiming to check whether the output of currently installed boilers matches the use requirements together with estimation of their energy efficiency was carried out on a group of 84 single-family residential buildings located in rural areas. Heating and hot water energy needs were calculated for each building in order to determine the use requirements. This enabled verification whether the currently installed boilers match the actual use requirements in the buildings. Based on the ...

Modelica Library for Building Heating, Ventilation and Air-Conditioning Systems

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael

2009-06-17

This paper presents a freely available Modelica library for building heating, ventilation and air conditioning systems. The library is based on the Modelica.Fluid library. It has been developed to support research and development of integrated building energy and control systems. The primary applications are controls design, energy analysis and model-based operation. The library contains dynamic and steady-state component models that are applicable for analyzing fast transients when designing control algorithms and for conducting annual simulations when assessing energy performance. For most models, dimensional analysis is used to compute the performance for operating points that differ from nominal conditions. This allows parameterizing models in the absence of detailed geometrical information which is often impractical to obtain during the conceptual design phase of building systems. In the first part of this paper, the library architecture and the main classes are described. In the second part, an example is presented in which we implemented a model of a hydronic heating system with thermostatic radiator valves and thermal energy storage.

Operation of heat pumps for smart grid integrated buildings with thermal energy storage

NARCIS (Netherlands)

Finck, C.J.; Li, R.; Zeiler, W.

2017-01-01

A small scale office building consisting of radiant heating, a heat pump, and a water thermal energy storage tank is implemented in an optimal control framework. The optimal control aims to minimize operational electricity costs of the heat pump based on real-time power spot market prices. Optimal

Modeling of District Heating Networks for the Purpose of Operational Optimization with Thermal Energy Storage

Science.gov (United States)

Leśko, Michał; Bujalski, Wojciech

2017-12-01

The aim of this document is to present the topic of modeling district heating systems in order to enable optimization of their operation, with special focus on thermal energy storage in the pipelines. Two mathematical models for simulation of transient behavior of district heating networks have been described, and their results have been compared in a case study. The operational optimization in a DH system, especially if this system is supplied from a combined heat and power plant, is a difficult and complicated task. Finding a global financial optimum requires considering long periods of time and including thermal energy storage possibilities into consideration. One of the most interesting options for thermal energy storage is utilization of thermal inertia of the network itself. This approach requires no additional investment, while providing significant possibilities for heat load shifting. It is not feasible to use full topological models of the networks, comprising thousands of substations and network sections, for the purpose of operational optimization with thermal energy storage, because such models require long calculation times. In order to optimize planned thermal energy storage actions, it is necessary to model the transient behavior of the network in a very simple way - allowing for fast and reliable calculations. Two approaches to building such models have been presented. Both have been tested by comparing the results of simulation of the behavior of the same network. The characteristic features, advantages and disadvantages of both kinds of models have been identified. The results can prove useful for district heating system operators in the near future.

Comfort air temperature influence on heating and cooling loads of a residential building

Science.gov (United States)

Stanciu, C.; Șoriga, I.; Gheorghian, A. T.; Stanciu, D.

2016-08-01

The paper presents the thermal behavior and energy loads of a two-level residential building designed for a family of four, two adults and two students, for different inside comfort levels reflected by the interior air temperature. Results are intended to emphasize the different thermal behavior of building elements and their contribution to the building's external load. The most important contributors to the building thermal loss are determined. Daily heating and cooling loads are computed for 12 months simulation in Bucharest (44.25°N latitude) in clear sky conditions. The most important aspects regarding sizing of thermal energy systems are emphasized, such as the reference months for maximum cooling and heating loads and these loads’ values. Annual maximum loads are encountered in February and August, respectively, so these months should be taken as reference for sizing thermal building systems, in Bucharest, under clear sky conditions.

An evaluation of solar energy for heating a highway maintenance headquarters building.

Science.gov (United States)

1985-01-01

A highway maintenance area headquarters building having overall dimensions of 64 ft - 8 in by 42 ft - 0 in was equipped with an active solar heating system to assist in heating space and domestic hot water. The solar system was instrumented and its o...

Sizing Combined Heat and Power Units and Domestic Building Energy Cost Optimisation

Directory of Open Access Journals (Sweden)

Dongmin Yu

2017-06-01

Full Text Available Many combined heat and power (CHP units have been installed in domestic buildings to increase energy efficiency and reduce energy costs. However, inappropriate sizing of a CHP may actually increase energy costs and reduce energy efficiency. Moreover, the high manufacturing cost of batteries makes batteries less affordable. Therefore, this paper will attempt to size the capacity of CHP and optimise daily energy costs for a domestic building with only CHP installed. In this paper, electricity and heat loads are firstly used as sizing criteria in finding the best capacities of different types of CHP with the help of the maximum rectangle (MR method. Subsequently, the genetic algorithm (GA will be used to optimise the daily energy costs of the different cases. Then, heat and electricity loads are jointly considered for sizing different types of CHP and for optimising the daily energy costs through the GA method. The optimisation results show that the GA sizing method gives a higher average daily energy cost saving, which is 13% reduction compared to a building without installing CHP. However, to achieve this, there will be about 3% energy efficiency reduction and 7% input power to rated power ratio reduction compared to using the MR method and heat demand in sizing CHP.

Solar thermal energy / exhaust air heat pump / wood pellet furnace for a sustainable heat supply of low energy buildings in older buildings; Solarthermie / Abluft-Waermepumpe / Pelletofen. Kombisysteme zur nachhaltigen Waermeversorgung von Niedrigenergiehaeusern im Gebaeudebestand

Energy Technology Data Exchange (ETDEWEB)

Diefenbach, Nikolaus; Born, Rolf [Institut Wohnen und Umwelt GmbH, Darmstadt (Germany); Staerz, Norbert [Ingenieurbuero inPlan, Pfungstadt (Germany)

2009-11-13

The research project under consideration reports on combination systems for a sustainable heat supply for low-energy buildings in older building. For this, a central and decentralized system configuration consisting of solar thermal energy, exhaust air heat pump and wood pellet furnace are presented. Solutions for an interaction of these three heat suppliers in one plant are designated regarding the control strategy. The fundamentals of the computerized simulations for the central and decentralized system are presented. A cost estimate with both variants of the combination system as well as a comparison with conventional energy-saving heat supply systems follow.

Dynamic simulation of space heating systems with radiators controlled by TRVs in buildings

Energy Technology Data Exchange (ETDEWEB)

Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, School of Architecture, Tsinghua University, Beijing 100084 (China)

2008-07-01

The objective of this paper is to develop a model for simulating the thermal and hydraulic behavior of space heating systems with radiators controlled by thermostat valves (TRVs) in multi-family buildings. This is done by treating the building and the heating system as a complete entity. Sub-models for rooms, radiators, TRVs, and the hydraulic network are derived. Then the suggested sub-models are combined to form an integrated model by considering interactions between them. The proposed model takes into account the heat transfer between neighboring rooms, the transport delay in the radiator, the self-adjusting function of the TRV, and the consumer's regulation behavior, as well as the hydraulic interactions between consumers. To test the model, two space heating systems in Beijing and Tianjin were investigated, and the model was validated under three operation modes. There was good agreement between the measured and simulated values for room temperature, return water temperature, and flow rate. A modeling analysis case was given based on an existing building and heating system. It was found that when the set value of the TRVs were kept on 2-3, about 12.4% reduction of heat consumption could be gained, compared with the situation in which the TRVs were kept fully open. The water flow rate was an important index that truly reflected the heat load change. It was also noted that if the flow rate or supply water temperature changed much during the transport delay time in the radiator, ignoring the transport delay would introduce an obvious deviation of the simulation results. Additionally, when an apartment stopped using the heating system during a heating season, the heat consumption of its neighboring apartments would be increased about 6-14%. (author)

Weldability of general purpose heat source new-process iridium

International Nuclear Information System (INIS)

Kanne, W.R.

1987-01-01

Weldability tests on General Purpose Heat Source (GPHS) iridium capsules showed that a new iridium fabrication process reduced susceptibility to underbead cracking. Seventeen capsules were welded (a total of 255 welds) in four categories and the number of cracks in each weld was measured

Impact of coupled heat and moisture transfer effects on buildings energy consuption

Directory of Open Access Journals (Sweden)

Ferroukhi Mohammed Yacine

2017-01-01

Full Text Available Coupled heat, air, and moisture transfers through building envelope have an important effect on prediction of building energy requirements. Several works were conducted in order to integrate hygrothermal transfers in dynamic buildings simulations codes. However, the incorporation of multidirectional hygrothermal transfer analysis in the envelope into building simulation tools is rarely considered. In this work, coupled heat, air, and moisture (HAM transfer model in multilayer walls was established. Thereafter, the HAM model is coupled dynamically to a building behavior code (BES.The coupling concerns a co-simulation between COMSOL Multiphysics and TRNSYS software. Afterward, the HAM-BES co-simulation accuracy was verified. Then, HAM-BES co-simulation platform was applied to a case study with various types of climates (temperate, hot and humid, cold and humid. Three simulations cases were carried out. The first simulation case consists of the TRNSYS model without HAM transfer model. The second simulation case, 1-D HAM model for the envelope was integrated in TRNSYS code. For the third one, 1-D HAM model for the wall and 2-D HAM model for thermal bridges were coupled to the thermal building model of TRNSYS. Analysis of the results confirms the significant impact of 2-D envelope hygrothermal transfers on the indoor thermal and moisture behavior of building as well as on the energy building assessment. These conclusions are shown for different studied climates.

Impact of domestic and tertiary buildings heating by natural gas in the Italian context

International Nuclear Information System (INIS)

Aste, Niccolò; Del Pero, Claudio

2012-01-01

Natural Gas (NG) is commonly used for satisfying population needs for heating, domestic hot water production and cooking, particularly in countries where the price of electricity is high. Typically, NG is extensively distributed on urbanized territory and can be exploited by using different technologies. As a consequence, primary energy is usually consumed directly in buildings, allowing high efficiency conversion but also producing pollutants in urban areas. In this paper a comprehensive analysis on NG use in the Italian domestic and tertiary building sector has been carried out, in order to evaluate energy and environmental impact of this fuel on different climatic and geographical contexts, also considering the temporal fluctuation of consumption. The aim of the work is to trace a reliable and up-to-date scenario of NG employment for building heating in Italy, which is one of the EU countries where this source is more widely used. The study was carried out under the research program “Analysis and evaluation of the current status of the reduction measures of environmental impacts due to heating energy consumption in Italy”, funded by the Italian Ministry of Environment. The data presented are an essential basis for the development of building energy efficiency and consumption rationalization policies. - Highlights: ► Detailed assessment of natural gas consumption and emission for residential and tertiary buildings heating in Italy. ► Estimation of the average specific primary energy consumption for households heating in different climatic contexts. ► Nationwide, it is the first study on the whole country with this level of detail.

Numerical analysis of a magnetocaloric heat pump implementation into a residential building

DEFF Research Database (Denmark)

Johra, Hicham

of the magneto-caloric heat pump in a single hydronic loop coupling directly the heat source and the heat sink without additional heat exchangers. Moreover, several parameters can be controlled in order to perform efficient part load power generation. The objective of this work is to understand how to integrate...... a magneto-caloric heat pump into a residential building and establish a control strategy for such device. A numerical model of a single family house with water based under-floor heating and horizontal ground source heat exchanger is created. It is used to demonstrate the feasibility and the advantages...... of the integrated magneto-caloric heat pump system is compared with conventional heat pumps one....

Electric heating of religious buildings; Chauffage des lieux de culte par l`electricite

Energy Technology Data Exchange (ETDEWEB)

Jicquel, J M; Collober, M; Veyrat, O [Electricite de France, 92 - Clamart (France). Direction des Etudes et Recherches

1997-06-01

This paper reports on in-situ measurements performed in churches which allow to retain interesting solutions for electric heating. Churches are characterized by an important thermal inertia, a huge volume, an intermittency of use (some few hours a week) and by thermal, physical and chemical constraints for the good preservation of works of art and general esthetics of the building, in particular in the case of listed historical monuments. The installation of heating systems in such monuments requires authorizations from the historical monuments, the sacred art and the safety commissions. This paper summarizes the regulations and recommendations concerning: the thermal insulation, the heating regulation and programming, the ventilation, the fire safety, the electrical installation and the lighting. Then, the available electric powered heating systems are reviewed and described in details (principle, dimension, regulation, domain of use, installation): radiant short-infrared emitters, heating moquettes and heating pews. The choice criteria for a given heating system are analyzed according to the different constraints of the building (size, architecture, regulations, comfort, consumption costs) and finally the advantages of electric power heating are listed (no combustion products, low temperature stratification, aesthetics, silence and service life). (J.S.)

Feasibility of ground coupled heat pumps in office buildings: A China study

International Nuclear Information System (INIS)

Zhou, Zhihua; Zhang, Zhiming; Chen, Guanyi; Zuo, Jian; Xu, Pan; Meng, Chong; Yu, Zhun

2016-01-01

Highlights: • Feasibility of GCHPs in office buildings was assessed in various climatic regions. • Performance of GCHPs was compared with traditional heating and cooling techniques. • Ratio of the heating to cooling load has significant impacts on operation of GCHPs. - Abstract: Ground coupled heat pumps (GCHPs) have been widely applied in China due to its environmental friendliness and energy efficiency. However, it may not be appropriate in all geographical areas because a variety of factors (e.g. original soil temperature, peak cooling and heating load, and running time) vary significantly. Typical office buildings were selected from five cities that are located in different climatic regions. The QUick Energy Simulation Tool (e-QUEST) was utilized to simulate the cooling and heating load. Similarly, the Transient System Simulation Program (TRNSYS) was employed to simulate the 20-year variation of the average soil temperature and the Coefficient of Performance (COP) of GCHP units. Consequently, the feasibility of the GCHPs in different regions was analyzed. The results show that GCHP system is feasible in severe cold B regions such as Shenyang and cold regions such as Beijing as both cold and heat sources because of its energy efficiency. From the economy and operation performance’s perspective, GCHP system is not feasible in severe cold A regions such as Harbin; hot-summer and cold-winter regions such as Nanjing; and hot-summer and warm-winter region such as Guangzhou. This is due to the poor energy efficiency of the system, mainly attributed to a large gap between cumulative energy consumption for cooling and for heating. Comprehensive analysis of experiment results showed that the GCHP system of case building in cold region can operate stably in long term with a high efficiency when the ratio of annual cumulative cooling energy consumption to annual cumulative heating energy consumption ranges from 0.2:1 to 5:1. In severe cold B regions, GCHP system

New external convective heat transfer coefficient correlations for isolated low-rise buildings

Energy Technology Data Exchange (ETDEWEB)

Emmel, M. G.; Mendes, N. [Pontifical Catholic University of Parana, PUCPR/CCET, Thermal Systems Laboratory, LST, Curitiba (Brazil); Abadie, M. O. [Pontifical Catholic University of Parana, PUCPR/CCET, Thermal Systems Laboratory, LST, Curitiba (Brazil); Laboratoire d' Etude des Phenomenes de Transfert Appliques au batiment (LEPTAB), University of La Rochelle, La Rochelle (France)

2007-07-01

Building energy analyses are very sensitive to external convective heat transfer coefficients so that some researchers have conducted sensitivity calculations and proved that depending on the choice of those coefficients, energy demands estimation values can vary from 20% to 40%. In this context, computational fluid dynamics calculations have been performed to predict convective heat transfer coefficients at the external surfaces of a simple shape low-rise building. Effects of wind velocity and orientation have been analyzed considering four surface-to-air temperature differences. Results show that the convective heat transfer coefficient value strongly depends on the wind velocity, that the wind direction has a notable effect for vertical walls and for roofs and that the surface-to-air temperature difference has a negligible effect for wind velocity higher than 2 m/s. External convective heat transfer coefficient correlations are provided as a function of the wind free stream velocity and wind-to-surface angle. (author)

Energy statistics for one- and two-dwelling buildings in 2007; Energistatistik foer smaahus 2007

Energy Technology Data Exchange (ETDEWEB)

2009-01-15

The survey of energy statistics in 2007 on one- and two-dwelling buildings, including agricultural one- and two-dwelling buildings, is based on a sample of 6,849 buildings. The survey was carried out as a mail survey in June 2007. The non-response rate was 37 percent. The presentation provides data on energy use, number of one- and two-dwelling buildings, and heated floor areas for the total population and for various subdivisions. The use of oil for hot water and heating of one- and two-dwelling buildings has decreased by 23 percent compared to 2006, and by 71 percent the last 5 years. The number of air heat pumps increased by 41 per cent compared to 2006 and the total number of heat pumps increased from over 500 000 to over 650 000. More than 45 percent of the one- and two-dwelling buildings are heated by electricity exclusively, including buildings heated by air heat pump. About 20 percent are heated by a combination of bio fuel and electricity and about 3 percent are heated by oil exclusively. 17,200 kWh electricity per household in one- and two-dwelling buildings heated by direct electricity exclusively and 20,300 kWh in one- and two-dwelling buildings heated by water-borne electricity exclusively or 132 kWh per square metre of heated surface area (incl. electricity for household purposes). 2.8 cubic metres of oil per household in one- and two-dwelling buildings heated by oil exclusively or 19.9 litres of oil per square metre of heated surface area. 13.5 TWh electricity for households in one- and two-dwelling buildings, including the electricity used in combinations with other types of heating, but excluding electricity for household purposes which is estimated to 10,4 TWh. 258,000 cubic metres of oil (about 2.6 TWh) for households in one- and two-dwelling buildings. This includes mixed heating. 6.6 millions cubic metres of firewood in one- and two-dwelling buildings, 975,000 cubic metres of wood chips and 461,000 tons of pellets. This amount corresponds to 11

Influence of the convective surface transfer coefficients on the Heat, Air, and Moisture (HAM) building performance

DEFF Research Database (Denmark)

Steskens, Paul Wilhelmus Maria Hermanus; Janssen, Hans; Rode, Carsten

2009-01-01

Current models to predict heat, air and moisture (HAM) conditions in buildings assume constant boundary conditions for the temperature and relative humidity of the neighbouring air and for the surface heat and moisture transfer coefficients. These assumptions may introduce errors in the predicted...... influence on the predicted hygrothermal conditions at the surface of a building component and on the heat and vapour exchange with the indoor environment....

Investigation of the Indoor Environment in a Passive House Apartment Building Heated by Ventilation Air

DEFF Research Database (Denmark)

Lysholt Hansen, MathiasYoung Bok; Koulani, Chrysanthi Sofia; Peuhkuri, Ruut Hannele

2014-01-01

comfort and the performance of the air heating system and solar shading. Thermal comfort category B according to ISO 7730 was obtained in the building during field measurements, indicating that the air heating system was able to maintain comfort conditions in winter, when the outdoor temperature had been...... building project finished medio 2012. The design challenge was met with a concept of air heating that is individually controlled in every room. It also applies external solar shading. This study used indoor climate measurements and dynamic simulations in one of these apartment buildings to evaluate thermal...... unusual low for a longer period. The dynamic simulations also indicated that air heating during winter can provide a comfortable thermal environment. Dynamic simulations also demonstrated that during summer, apartments with automatic external solar screens had no serious overheating, whereas in apartments...

Calculation of the yearly energy performance of heating systems based on the European Building Energy Directive and related CEN Standards

DEFF Research Database (Denmark)

Olesen, Bjarne W.; de Carli, Michele

2011-01-01

According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting syst......–20% of the building energy demand. The additional loss depends on the type of heat emitter, type of control, pump and boiler. Keywords: Heating systems; CEN standards; Energy performance; Calculation methods......According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting...... systems. This energy declaration must refer to the primary energy or CO2 emissions. The European Organization for Standardization (CEN) has prepared a series of standards for energy performance calculations for buildings and systems. This paper presents related standards for heating systems. The relevant...

General-purpose heat source development. Phase I: design requirements

International Nuclear Information System (INIS)

Snow, E.C.; Zocher, R.W.

1978-09-01

Studies have been performed to determine the necessary design requirements for a 238 PuO 2 General-Purpose Heat Source (GPHS). Systems and missions applications, as well as accident conditions, were considered. The results of these studies, along with the recommended GPHS design requirements, are given in this report

Heating and cooling energy demand and related emissions of the German residential building stock under climate change

International Nuclear Information System (INIS)

Olonscheck, Mady; Holsten, Anne; Kropp, Juergen P.

2011-01-01

The housing sector is a major consumer of energy. Studies on the future energy demand under climate change which also take into account future changes of the building stock, renovation measures and heating systems are still lacking. We provide the first analysis of the combined effect of these four influencing factors on the future energy demand for room conditioning of residential buildings and resulting greenhouse gas (GHG) emissions in Germany until 2060. We show that the heating energy demand will decrease substantially in the future. This shift will mainly depend on the number of renovated buildings and climate change scenarios and only slightly on demographic changes. The future cooling energy demand will remain low in the future unless the amount of air conditioners strongly increases. As a strong change in the German energy mix is not expected, the future GHG emissions caused by heating will mainly depend on the energy demand for future heating. - Highlights: → The future heating energy demand of German residential buildings strongly decreases. → Extent of these changes mainly depends on the number of renovated buildings. → Demographic changes will only play a minor role. → Cooling energy demand will remain low in future but with large insecurities. → Germany's 2050 emission targets for the building stock are ambitious.

Ground source heat pumps designed for earth-sheltered, low-energy atrium building

NARCIS (Netherlands)

Pawlovski, A.; Heim, D.; Hensen, J.L.M.

2003-01-01

One of the main strategies in design of earth-sheltered buildings is to reduce heat losses in the winter and heat gains in the summer by using the relatively stable thermal conditions of the soil. Additionally, construction work carried out at the site allows a reduction of the installation costs

Kyiv institutional buildings sector energy efficiency program: Technical assessment

Energy Technology Data Exchange (ETDEWEB)

Secrest, T.J.; Freeman, S.L. [Pacific Northwest National Lab., Richland, WA (United States); Popelka, A. [Tysak Engineering, Acton, MA (United States); Shestopal, P.A.; Gagurin, E.V. [Agency for Rational Energy Use and Ecology, Kyiv (Ukraine)

1997-08-01

The purpose of this assessment is to characterize the economic energy efficiency potential and investment requirements for space heating and hot water provided by district heat in the stock of state and municipal institutional buildings in the city of Kyiv. The assessment involves three activities. The first is a survey of state and municipal institutions to characterize the stock of institutional buildings. The second is to develop an estimate of the cost-effective efficiency potential. The third is to estimate the investment requirements to acquire the efficiency resource. Institutional buildings are defined as nonresidential buildings owned and occupied by state and municipal organizations. General categories of institutional buildings are education, healthcare, and cultural. The characterization activity provides information about the number of buildings, building floorspace, and consumption of space heating and hot water energy provided by the district system.

Check and evaluation system on heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of china based on multi-index comprehensive evaluation method

International Nuclear Information System (INIS)

Zhao Jing; Wu Yong; Zhu Neng

2009-01-01

Heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of China is organized and implemented in a large scale by local government in 15 provinces of North China with the unified guidance and control of central government. Firstly, this paper introduced the target of energy-saving reformation of existing residential buildings in North China and the importance of check and evaluation on this target, then pointed out the necessity of building up an evaluation system for energy-saving retrofit. According to the analytical hierarchy process (AHP), three-grade evaluation system was built up for heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of China. Also, based on multi-index comprehensive evaluation method combined with life cycle assessment (LCA) theory, post-evaluation thought and successful degree evaluation method, a mathematical model was established. Finally, a set of scientific method for evaluating heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of China systematically, scientifically, comprehensively and objectively was created.

Pseudo dynamic transitional modeling of building heating energy demand using artificial neural network

NARCIS (Netherlands)

Paudel, S.; Elmtiri, M.; Kling, W.L.; Corre, le O.; Lacarriere, B.

2014-01-01

This paper presents the building heating demand prediction model with occupancy profile and operational heating power level characteristics in short time horizon (a couple of days) using artificial neural network. In addition, novel pseudo dynamic transitional model is introduced, which consider

Combined Heat and Power Dispatch Considering Heat Storage of Both Buildings and Pipelines in District Heating System for Wind Power Integration

Directory of Open Access Journals (Sweden)

Ping Li

2017-06-01

Full Text Available The strong coupling between electric power and heat supply highly restricts the electric power generation range of combined heat and power (CHP units during heating seasons. This makes the system operational flexibility very low, which leads to heavy wind power curtailment, especially in the region with a high percentage of CHP units and abundant wind power energy such as northeastern China. The heat storage capacity of pipelines and buildings of the district heating system (DHS, which already exist in the urban infrastructures, can be exploited to realize the power and heat decoupling without any additional investment. We formulate a combined heat and power dispatch model considering both the pipelines’ dynamic thermal performance (PDTP and the buildings’ thermal inertia (BTI, abbreviated as the CPB-CHPD model, emphasizing the coordinating operation between the electric power and district heating systems to break the strong coupling without impacting end users’ heat supply quality. Simulation results demonstrate that the proposed CPB-CHPD model has much better synergic benefits than the model considering only PDTP or BTI on wind power integration and total operation cost savings.

Energy statistics for one- and two-dwelling buildings in 2008; Energistatistik foer smaahus 2008

Energy Technology Data Exchange (ETDEWEB)

2009-09-15

The survey of energy statistics in 2008 on one- and two-dwelling buildings, including agricultural one- and two-dwelling buildings, is based on a sample of 6 852 buildings. The survey was carried out as a mail survey in June 2008. The non-response rate was 39 percent. The presentation provides data on energy use, number of one- and two-dwelling buildings, and heated floor areas for the total population and for various subdivisions. During the last two years the number one- and two-dwelling buildings heated solely by district heating has greatly increased. The total use of district heating has increased by 32 percent. The use of oil for hot water and heating of one- and two dwelling buildings has decreased by 21 percent compared to 2007, and by 75 percent during the last five-year period. Nearly 40 percent of one- and two-dwelling buildings are heated completely or partially with a heat pump. However, the sharp increase in the number of heat pumps during the last five-year period has nearly come to a standstill in the last two years. About 42 percent of all one- and two-dwelling buildings in Sweden are heated by electricity as the only source of heat, including houses that are heated by heat pumps. Combined heating with electricity and biomass fuel is the second most common heating method, followed by heating with solely biomass fuel. 17 100 kWh electricity per household in one- and two-dwelling buildings heated by direct electricity exclusively and 18 800 kWh in one- and two dwelling buildings heated by water-borne electricity exclusively or 130 kWh per square metre of heated surface area (incl. electricity for household purposes). 2.5 cubic metres of oil per household in one- and two-dwelling buildings heated by oil exclusively or 18.7 litres of oil per square metre of heated surface area. 12.7 TWh electricity for households in one- and two-dwelling buildings, including the electricity used in combinations with other types of heating, but excluding electricity for

Refrigeration Playbook. Heat Reclaim; Optimizing Heat Rejection and Refrigeration Heat Reclaim for Supermarket Energy Conservation

Energy Technology Data Exchange (ETDEWEB)

Reis, Chuck [CTA Architects Engineers, Boise, ID (United States); Nelson, Eric [CTA Architects Engineers, Boise, ID (United States); Armer, James [CTA Architects Engineers, Boise, ID (United States); Johnson, Tim [CTA Architects Engineers, Boise, ID (United States); Hirsch, Adam [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Doebber, Ian [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2015-03-01

The purpose of this playbook and accompanying spreadsheets is to generalize the detailed CBP analysis and to put tools in the hands of experienced refrigeration designers to evaluate multiple applications of refrigeration waste heat reclaim across the United States. Supermarkets with large portfolios of similar buildings can use these tools to assess the impact of large-scale implementation of heat reclaim systems. In addition, the playbook provides best practices for implementing heat reclaim systems to achieve the best long-term performance possible. It includes guidance on operations and maintenance as well as measurement and verification.

Bio energy heating plant heats municipal buildings in Nord-Odal; Bioenergisentral varmer kommunale bygg i Nord-Odal

Energy Technology Data Exchange (ETDEWEB)

2008-07-01

When Nord-Odal planned to build a new nursing home, they wanted to find a more environmental friendly heating system than based on oil and electricity. Several energy consultants evaluated the task. But when all consultants concluded there would be no cost benefit in this task, local experts looked into it - and because they got a long term agreement, it was possible to finance a local bio energy heat plant. (AG)

Performance of Radiant Heating Systems of Low-Energy Buildings

Science.gov (United States)

Sarbu, Ioan; Mirza, Matei; Crasmareanu, Emanuel

2017-10-01

After the introduction of plastic piping, the application of water-based radiant heating with pipes embedded in room surfaces (i.e., floors, walls, and ceilings), has significantly increased worldwide. Additionally, interest and growth in radiant heating and cooling systems have increased in recent years because they have been demonstrated to be energy efficient in comparison to all-air distribution systems. This paper briefly describes the heat distribution systems in buildings, focusing on the radiant panels (floor, wall, ceiling, and floor-ceiling). Main objective of this study is the performance investigation of different types of low-temperature heating systems with different methods. Additionally, a comparative analysis of the energy, environmental, and economic performances of floor, wall, ceiling, and floor-ceiling heating using numerical simulation with Transient Systems Simulation (TRNSYS) software is performed. This study showed that the floor-ceiling heating system has the best performance in terms of the lowest energy consumption, operation cost, CO2 emission, and the nominal boiler power. The comparison of the room operative air temperatures and the set-point operative air temperature indicates also that all radiant panel systems provide satisfactory results without significant deviations.

HEAT LOSS FROM HOT WATER SUPPLY LINE IN A RESIDENTIAL BUILDING

OpenAIRE

近藤, 修平; 鉾井, 修一

2011-01-01

In order to the evaluate heat loss from hot water supply lines in a residential building, hot water demand in a house in Chiba prefecture was measured and analyzed. The following results were obtained. 1. The heat loss of the hot water supply line was about 132kJ for the shower and 110kJ for the bathtub in winter. Since the temperature difference between the inlet and outlet of the hot water supply line is small, the measured heat loss from the hot water supply line sometimes becomes negative...

Energy reduction in buildings in temperate and tropic regions utilizing a heat loss measuring device

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt

2012-01-01

There exist two ordinary ways to obtain global energy efficiency. One way is to make improvements on the energy production and supply side, and the other way is, in general, to reduce the consume of energy in the society. This paper has focus on the latter and especially the consume of energy...... for heating up, and cooling down our houses. There is a huge energy saving potential on this area reducing both the World climate problems and economy challenges as well. Heating of buildings in Denmark counts for approximately 40% of the entire national energy consume. Of this reason a reduction of heat...... losses from building envelopes are of great impor­tance in order to reach the Bologna CO2-emission reduction goals. Energy renovation of buildings is a topic of huge focus around the world these years. Not only expenses for heating in the tempered and arctic regions are of importance, but also expenses...

ON REASONABLE ESTIMATE OF ENERGY PERFORMANCE OF THE RESIDENTIAL BUILDINGS SUSTENANCE WITH CENTRALIZED HEAT-SUPPLY SYSTEM

Directory of Open Access Journals (Sweden)

S. N. Osipov

2016-01-01

Full Text Available As consisted with Directive No 3 of President of the Republic of Belarus of June, 14th 2007 ‘Economy and Husbandry – the Major Factors of Economic Security of the Republic of Belarus’, saving fuel-and-energy resources over the republic in 2010–2015 should amount to 7,1–8,9 MIO tons of fuel equivalent including 1,00–1,25 MIO tons of fuel equivalent at the expense of heat-supply optimization and 0,25–0,40 MIO tons of fuel equivalent at the expense of increasing enclosing structures heat resistance of the buildings, facilities and housing stock. It means, where it is expected to obtain around 18 % of general thermal resources economy in the process of heat-supply optimization, then by means of enhancing the cladding structure heat resistance of the buildings and constructions of various applications – only about 3–5 % and even a bit less so of the housing stock. Till 1994, in residential sector of the Republic of Belarus, the annual heat consumption of the heating and ventilation averaged more than 130 kW×h/(m2×year (~56 %, of the hot-water supply – around 100 kW×h/(m2×year (~44 %. In residential houses, built from 1994 to 2009, heat consumption of the heating and ventilation is already 90 kW×h/(m2×year, of the hot-water supply – around 70 kW×h/(m2×year. In buildings of modern mainstream construction, they expend 60 kW×h/(m2×year (~46 % on heating and ventilation and 70 kW×h/(m2×year (~54 % on hot-water supply. In some modern residential buildings with the exhausted warm air secondary energy resource utilization, the heating and ventilation takes around 30–40 kW×h/(m2×year of heat. Raising energy performance of the residential buildings by means of reducing heat expenses on the heating and ventilation is the last segment in the system of energy resources saving. The first segments in the energy performance process are producing heat and transporting it over the main lines and outside distribution networks. In

Using Solar Hot Water to Address Piping Heat Losses in Multifamily Buildings

Energy Technology Data Exchange (ETDEWEB)

Springer, David [Alliance for Residential Building Innovation, Davis, CA (United States); Seitzler, Matt [Alliance for Residential Building Innovation, Davis, CA (United States); Backman, Christine [Alliance for Residential Building Innovation, Davis, CA (United States); Weitzel, Elizabeth [Alliance for Residential Building Innovation, Davis, CA (United States)

2015-10-01

Solar thermal water heating is most cost effective when applied to multifamily buildings and some states offer incentives or other inducements to install them. However, typical solar water heating designs do not allow the solar generated heat to be applied to recirculation losses, only to reduce the amount of gas or electric energy needed for hot water that is delivered to the fixtures. For good reasons, hot water that is recirculated through the building is returned to the water heater, not to the solar storage tank. The project described in this report investigated the effectiveness of using automatic valves to divert water that is normally returned through the recirculation piping to the gas or electric water heater instead to the solar storage tank. The valves can be controlled so that the flow is only diverted when the returning water is cooler than the water in the solar storage tank.

Analysis of the building system of four mills and their suitability for heat treatment pest disinfestation

Directory of Open Access Journals (Sweden)

Loredana Strano

2013-09-01

Full Text Available The last century researchers at Kansas State University demonstrated the validity of the heat treatment as a method of pest control in more than 20 mills. However factors such as the high capital investment required to heat large buildings, inadequate control of high temperatures and the risk of damage to parts of the plants or the construction materials have prevented the large-scale adoption of this technique as a viable alternative to fumigants. Today the combination of the industrialization of the food industry, the technological and structural modernization of plants and developments in heat disinfection technologies have resulted in interesting results being obtained for the use of this system in primary and secondary production processing plants, both experimentally and in practice. However, the scientific literature highlights some of the factors that limit the efficiency of the treatment. This is related to aspects of the buildings and the plants and the environment of the buildings. The structure of the buildings appear to have an enormous impact on energy consumption, because this depends on the amount of heating time and the methods that have to be used when establishing a heat treatment regime. These factors are important if the fumigation temperatures are to be reached in the shortest possible time and can affect the choice of the technique used with current fumigants, especially when this is combined with the amount and cost of the energy consumed. The aim of this work is to analyse four Sicilians mills that intend to use the heat system for fumigation and pest control in order to identify those aspects of the buildings, plant and their environment which are “critical elements” and may discourage the use of this technology. Particular attention was paid to the type of construction materials and their thermal conductivity (roof, floors and walls, the number and volume of the buildings and the distance between them, the

Feasibility study on novel hybrid ground coupled heat pump system with nocturnal cooling radiator for cooling load dominated buildings

International Nuclear Information System (INIS)

Man, Yi; Yang, Hongxing; Spitler, Jeffrey D.; Fang, Zhaohong

2011-01-01

Highlights: → Propose a novel HGCHP system with NCR works as supplemental heat rejecter. → Establish the analytical model and computer program of NCR and novel HGCHP system to simulate their operation performance. → Design the novel HGCHP system for a sample building located in Hong Kong. → It is found to be feasible to use NCR serves as supplemental heat rejecter of the novel HGCHP system. → The novel HGCHP system provides a new valuable choice for air conditioning in cooling load dominated buildings. -- Abstract: When the ground coupled heat pump (GCHP) system is utilized for air conditioning in cooling load dominated buildings, the heat rejected into ground will accumulate around the ground heat exchangers (GHE) and results in system performance degradation. A novel hybrid ground coupled heat pump (HGCHP) system with nocturnal cooling radiator (NCR) works as supplemental heat rejecter is proposed in this paper to resolve this problem. The practical analytical model of NCR and novel HGCHP system are established. The computer program based on established model is developed to simulate the system operation performance. The novel HGCHP system is designed and simulated for a sample building located in Hong Kong, and a simple life cycle cost comparisons are carried out between this system and conventional GCHP system. The results indicate that it is feasible to use NCR serves as supplemental heat rejecter of the novel HGCHP system for cooling load dominated buildings even those located in humid subtropical climate areas. This novel HGCHP system provides a new valuable choice for air conditioning in cooling load dominated buildings, and it is especially suitable for buildings with limited surface land areas.

Use of the water supply system of special purpose in buildings

Directory of Open Access Journals (Sweden)

Orlov Evgeniy Vladimirovich

Full Text Available A water supply system of a special purpose is a necessary element in hot and cold shops of the industrial enterprises, office buildings and the medical centers, and also other rooms. The water supply systems of a special purpose, which give subsalty, sparkling water and water sated with oxygen, allow people to prevent, for example, strong dehydration of an organism, which is possible at big losses of water, especially in case of the people working in hot shops. Various elements of special drinking water supply system are given in the article, their main functions are described. Different types of the water folding devices pumping water to consumers, one of which is drinking fountain, are considered. Possible systems of water filtration, which can be established for quality improvement, are transferred. Among them the great role is played by membrane technologies and the return osmosis, which is widely applied now. Today there is a possibility of construction, both the centralized water supply system of a special purpose, and local. Besides, the least is a more preferable option taking into account capital expenditure for construction and operation, and also it can lead to solid resource-saving as a result of the electric energy saving going for water heating in heaters. Automatic machines of drinking water for a local water supply system of a special purpose have indisputable advantages. They are capable to carry out several functions at the same time, and also to distribute water to consumers. It allows placing all the necessary equipment, which will be well in harmony with the environment in their small and compact case, and will fit into any difficult interior of the room. Also they are very easily connected to the systems of an internal water supply system by means of a propylene tube that allows to change their sposition in space and to transfer to any place of the room with fast installation of equipment. Also the ecological effect was

Potential Energy Flexibility for a Hot-Water Based Heating System in Smart Buildings Via Economic Model Predictive Control

DEFF Research Database (Denmark)

Ahmed, Awadelrahman M. A.; Zong, Yi; Mihet-Popa, Lucian

2017-01-01

This paper studies the potential of shifting the heating energy consumption in a residential building to low price periods based on varying electricity price signals suing Economic Model Predictive Control strategy. The investigated heating system consists of a heat pump incorporated with a hot...... water tank as active thermal energy storage, where two optimization problems are integrated together to optimize both the heat pump electricity consumption and the building heating consumption. A sensitivity analysis for the system flexibility is examined. The results revealed that the proposed...

STUDY OF SHELL FOR ENERGY EFFICIENT OF SUSTAINABLE LOW-RISE BUILDING

Directory of Open Access Journals (Sweden)

DANISHEVSKYI V. V.

2016-03-01

Full Text Available The article presents the results of study the shell for energy-efficient environmental low-rise residential building, corresponding to the criteria of sustainable development in construction. Purpose. The purpose of the presented research is providing a study of parameters for shell of energy-efficient environmental low-rise buildings. Methodology. Research is carried out on the basis of an improved method for calculating the thermal characteristics of the external walling, as well as physical heat transfer simulation. Conclusion.The ratio between the thickness of external walling and the proportion of heat loss through them was determined, and also the heat loss through thermal "bridges" was studied. Originality. The limits for the optimum thickness of the external walling of ecological materials was analyzed, and it was offered solution for minimization of heat loss through the nodes of shell. Practical value.Recommendations are worked out on constructing of thermal shell at planning of energy-efficient low-rise residential buildings.

Air-to-air heat recovery devices for small buildings : interim report

Science.gov (United States)

1981-01-01

With the escalation of fuel costs, many people are turning to tighter, better insulated buildings as a means of achieving energy conservation. This is especially true in northern climates, where heating seasons are long and severe. Installing efficie...

A flexible and low cost experimental stand for air source heat pump for Smart Buildings

DEFF Research Database (Denmark)

Crăciun, Vasile S.; Bojesen, Carsten; Blarke, Morten

2012-01-01

Energy systems are faced with the challenges of reducing dependency on fossil fuels, while handling increasing penetration levels of intermittent renewables such as wind and solar power. At the same time, the efficient consumption of energy is vital for avoiding the impacts from increasing fuel...... prices. A significant part of this challenge may be dealt with in the way space heating, space cooling, and domestic hot water production which is provided to residential and commercial buildings. Air source heat pumps (ASHP) are widely used conversion technologies for providing building thermal energy...... services; cooling, heating, and water heating. ASHP does not have a constant temperature for the primary source like: soil, ground water, or surface water heat pumps. In result, laboratory experiments and tests are faced by the problem of having to handle a wide range of conditions under which...

Estimation of heat rejection based on the air conditioner use time and its mitigation from buildings in Taipei City

Energy Technology Data Exchange (ETDEWEB)

Hsieh, Chun-Ming; Aramaki, Toshiya; Hanaki, Keisuke [The University of Tokyo, Bunkyo-ku, Tokyo (Japan). Department of Urban Engineering

2007-09-15

The main work in the research focuses on the analysis and mitigation of the anthropogenic heat discharged from buildings, which is one of the main reasons leading to the heat island effect. The residential and commercial buildings, divided into 10 categories, with HVAC systems were analyzed by the building energy program, EnergyPlus. With the help of GIS, the heat rejection of all the residential and commercial buildings in DaAn Ward of Taipei City were evaluated, in which the spatial data and diurnal variation of the heat rejection were described by 3-h time periods. Furthermore, the effect of mitigation strategies was discussed. The first strategy was to change the wall/roof material of building envelope. The second and third strategies, from the viewpoint of energy saving, were to change the temperature setting of air conditioners and to turn off the lighting and equipment when not in use. The fourth strategy was to use a better efficiency of the cooling systems. Finally, the evaluation of installing the water-cooled cooling system, which discharges heat in the form of sensible and latent heat, was also included. (author)

Assessment of Real Heat Transfer Coefficients through Shell and Tube and Plate Heat Exchangers

Directory of Open Access Journals (Sweden)

Dan CONSTANTINESCU

2011-07-01

Full Text Available The purpose of this paper is to present a procedure used in the assessment of the real heat transfer characteristic of shell and tube and plate heat exchangers. The theoretical fundamentals of the procedure are introduced as well as the measured data collection and processing. The theoretical analysis is focused on the adoption of criterial equations which, subjected to certain verification criteria presented in the paper, provide the most credible value of the convection heat transfer coefficients inside the circular and flat tubes. In the end two case studies are presented, one concerning a shell and tube heat exchanger operational at INCERC Thermal Substation and the other concerning a plate heat exchanger tested on the Laboratory Stand of the Department of Building Services and Efficient Use of Energy in Buildings of INCERC Bucharest.

Efficient modernisation of a panel building - (We reduced a panel house's heat consumption to one fourth)

Energy Technology Data Exchange (ETDEWEB)

Zsebik, Albin; Czinege, Zoltan

2010-09-15

In an EU pilot project called 'SOLANOVA', a 42-apartment building, was renovated and converted to a low energy consumption building in Dunaujvaros, Hungary in year 2005. The energy consumption of the building in the last four heating seasons was less than a quarter of the baseline consumption before the renovation. This presentation introduces the building and its energy consumption before the renovation; shows the aim, preparation and main steps of the renovation; and takes a look at the building and its heat consumption after the renovation.

Temperature Sensor Feasibility Study of Wireless Sensor Network Applications for Heating Efficiency Maintenance in High-Rise Apartment Buildings

Directory of Open Access Journals (Sweden)

Freliha B.

2015-06-01

Full Text Available Cities are responsible for 60%-80% of the world’s energy use and for approximately the same percentage of greenhouse gas emissions. The existing multi-apartment buildings of multifamily housing sector are often energy inefficient, and the heating system does not ensure optimization of heat distribution of individual apartments. Heat distribution, heating system balancing, heat loss detection and calculation, individual heat energy accounting are difficult tasks to accomplish. This article deals with the temperature monitoring system designed to retrieve temperature differences necessary for overall building heat monitoring and individual apartment monitoring. The sensor testing case study process and its measurements are analysed.

Optimization and Performance Study of Select Heating Ventilation and Air Conditioning Technologies for Commercial Buildings

Science.gov (United States)

Kamal, Rajeev

Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times. Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings: 1. Use of gas heat pumps in place of electric heat pumps, and 2. Shifting demand for air conditioning from peak to off-peak by thermal energy storage in chilled water and ice. The first part of this study evaluates the field performance of gas engine-driven heat pumps (GEHP) tested in a commercial building in Florida. Four GEHP units of 8 Tons of Refrigeration (TR) capacity each providing air-conditioning to seven thermal zones in a commercial building, were instrumented for measuring their performance. The operation of these GEHPs was recorded for ten months, analyzed and compared with prior results reported in the literature. The instantaneous COPunit of these systems varied from 0.1 to 1.4 during typical summer week operation. The COP was low because the gas engines for the heat pumps were being used for loads that were much lower than design capacity which resulted in much lower efficiencies than expected. The performance of equivalent electric heat pump was simulated from a building energy model developed to mimic the measured building loads. An economic comparison of GEHPs and conventional electrical heat pumps was done based on the measured and simulated results. The average performance of the GEHP units was estimated to lie between those of EER-9.2 and EER-11.8 systems. The performance of GEHP systems suffers due to lower efficiency at

Utilization of waste heat from nuclear power plants in agriculture

International Nuclear Information System (INIS)

Horacek, P.

1981-01-01

The development of nuclear power will result in the relative and absolute increase in the amount of waste heat which can be used in agriculture for heating greenhouses, open spaces, for fish breeding in heated water, for growing edible mushrooms, growing algae, for frost protection of orchards, air conditioning of buildings for breeding livestock and poultry, and for other purposes. In addition of the positive effect of waste heat, the danger increases of disease, weeds and pests. Pilot plant installations should be build in Czechoslovakia for testing the development of waste heat utilization. (Ha)

Solar Heating and Cooling of Buildings: Activities of the Private Sector of the Building Community and Its Perceived Needs Relative to Increased Activity.

Science.gov (United States)

National Academy of Sciences - National Research Council, Washington, DC. Committee on Solar Energy in the Heating and Cooling of Buildings.

This report is essentially a collection of information gathered from a broad cross-section of the building community that provides a description of the state of affairs existing mid-1974 through mid-1975 in the private sector of the building community with regard to solar heating and cooling of buildings. The report additionally contains…

Heating and cooling energy demand in underground buildings : potential for saving in various climates and functions

NARCIS (Netherlands)

van Dronkelaar, C.; Costola, D.; Mangkuto, R.A.; Hensen, J.L.M.

2014-01-01

Underground buildings are pointed out as alternatives to conventional aboveground buildings for reducing total energy requirements, while alleviating land use and location problems. This paper investigates the potential in reducing the heating and cooling energy demand of underground buildings

Solar Energy for Space Heating & Hot Water.

Science.gov (United States)

Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

This pamphlet reviews the direct transfer of solar energy into heat, particularly for the purpose of providing space and hot water heating needs. Owners of buildings and homes are provided with a basic understanding of solar heating and hot water systems: what they are, how they perform, the energy savings possible, and the cost factors involved.…

Solar heating and hot water system installed at Municipal Building complex, Abbeville, South Carolina

Science.gov (United States)

1979-01-01

Information on the solar energy system installed at the new municipal building for the City of Abbeville, SC is presented, including a description of solar energy system and buildings, lessons learned, and recommendations. The solar space heating system is a direct air heating system. The flat roof collector panel was sized to provide 75% of the heating requirement based on an average day in January. The collectors used are job-built with two layers of filon corrugated fiberglass FRP panels cross lapped make up the cover. The storage consists of a pit filled with washed 3/4 in - 1 1/2 in diameter crushed granite stone. The air handler includes the air handling mechanism, motorized dampers, air circulating blower, sensors, control relays and mode control unit. Solar heating of water is provided only those times when the hot air in the collector is exhausted to the outside.

Alternative energy sources for the heating and cooling of a building

CSIR Research Space (South Africa)

Strydom, JFS

1979-11-27

Full Text Available The objective of two of the studies was to choose the most economical source of heating energy, taking cognizance of the building owner’s particular circumstances; in both cases a suitable alternative to light petroleum oil, which had been used...

Building Modelling Methodologies for Virtual District Heating and Cooling Networks

Energy Technology Data Exchange (ETDEWEB)

Saurav, Kumar; Choudhury, Anamitra R.; Chandan, Vikas; Lingman, Peter; Linder, Nicklas

2017-10-26

District heating and cooling systems (DHC) are a proven energy solution that has been deployed for many years in a growing number of urban areas worldwide. They comprise a variety of technologies that seek to develop synergies between the production and supply of heat, cooling, domestic hot water and electricity. Although the benefits of DHC systems are significant and have been widely acclaimed, yet the full potential of modern DHC systems remains largely untapped. There are several opportunities for development of energy efficient DHC systems, which will enable the effective exploitation of alternative renewable resources, waste heat recovery, etc., in order to increase the overall efficiency and facilitate the transition towards the next generation of DHC systems. This motivated the need for modelling these complex systems. Large-scale modelling of DHC-networks is challenging, as it has several components interacting with each other. In this paper we present two building methodologies to model the consumer buildings. These models will be further integrated with network model and the control system layer to create a virtual test bed for the entire DHC system. The model is validated using data collected from a real life DHC system located at Lulea, a city on the coast of northern Sweden. The test bed will be then used for simulating various test cases such as peak energy reduction, overall demand reduction etc.

Energy in the residential building. Electricity, heat, e-mobility. 2. rev. and enl. ed.

International Nuclear Information System (INIS)

Schwarzburger, Heiko

2017-01-01

Photovoltaics, heat pumps and fuel cells offer enormous potential for sustainable energy supply in residential buildings. Solar thermal energy and wood-fired boilers also play an important role in refurbishment. Due to the wide range of possible combinations, the wishes of building owners and homeowners for an ecologically and economically individually adapted energy concept can be fulfilled accurately. This book provides you with a holistic approach to the residential building and its supply of electricity, heat and water. All processes that play a role in the house's energy consumption are examined in their entirety for their potentials and potential savings. The author analyses and describes in detail the resources of buildings and their surroundings - and how they can be used for a truly independent supply. The focus is on reducing energy consumption and costs, the generation and supply of energy from renewable sources and energy storage - considered in new construction and modernisation. The supply of water is also dealt with if it touches on energy issues. The author draws attention to standards and regulations and gives practical advice for planning and installation. The focus is on the so-called sector coupling: electricity from the sun, wind and hydrogen is used to supply electrical consumers in the home, charging technology for electric vehicles, hot water and heating. The time of the boilers and combustion engines has elapsed. Clean electricity and digital controls - power and intelligence - determine the regenerative building technology. [de

Energy savings in the Danish building stock until 2050

DEFF Research Database (Denmark)

Wittchen, Kim Bjarne; Kragh, Jesper

2014-01-01

are energy upgraded according to the requirements stipulated in the Danish Building Regulations 2010. Furthermore, scenario analyses was made for the potential impact on the energy consumption of introducing different levels of tightening of the energy requirements for existing buildings in the Danish...... Building Regulations. Compliance with the requirements in the Danish Building Regulations will potentially result in energy savings for space heating and domestic hot water around 30 % until 2050. Further tightening of the component insulation level requirements will only result in marginally higher......A study has been conducted analysing the energy savings for space heating and domestic hot water in the Danish building stock due to renovation of building components at the end of their service life. The purpose of the study was to estimate the energy savings until 2050 as building components...

Development of a new controller for simultaneous heating and cooling of office buildings

DEFF Research Database (Denmark)

Maccarini, Alessandro; Afshari, Alireza; Hultmark, Göran

2016-01-01

by signals of actual room air temperatures and return water temperature. Depending on the minimum and maximum air temperatures in the rooms, the supply water temperature was set by adjusting the return water temperature with two offsets, one for heating demand and one for cooling demand. The behaviour......This paper aims to develop a new controller to regulate the supply water temperature of a room-temperature loop integrated in a novel HVAC for office buildings. The main feature of the room-temperature loop is its ability to provide simultaneous heating and cooling by circulating water...... with a temperature of about 22 °C. Therefore, the same supply water temperature is delivered to all the thermal zones in the building, no matter whether a single zone needs heating or cooling. In previous studies, the supply water temperature varied between 20 °C and 23 °C, according to outdoor air temperature...

Combustion of soybean oil and diesel mixtures for heating purposes

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, Adriana Correa; Sanz, Jose Francisco [European University Miguel de Cervantes, Valladolid (Spain)], E-mail: acorrea@uemc.es; Hernandez, Salvador; Navas, Luis Manuel; Rodriguez, Elena; Ruiz, Gonzalo [University of Valladolid (Spain). Dept. of Agricultural and Forest Engineering; San Jose, Julio [University of Valladolid (Spain). Dept. of Energetic Engineering; Gomez, Jaime [University of Valladolid (Spain). Dept. of Communications and Signal Theory and Telematics Engineering

2008-07-01

Using blends of vegetable oils with petroleum derivates for heating purposes has several advantages over other energy application for vegetable oils. This paper presents the results of an investigation by use of soybean oil and diesel mixture as fuel for producing heat in conventional diesel installation. The paper is set out as follows: properties characterization of soybean oil as fuel and of diesel oil, as well as the mixture of both; selection of the mixture according to their physical chemical properties and how they adapt to conventional combustion installation; experimentation with the selected mixture, allowing the main combustion parameters to be measured; processing the collected data, values of combustion, efficiency and reduction of emissions. Conclusions show that the use of soybean oil and diesel mixture for producing heat energy in conventional equipment is feasible and beneficial for reduction emissions. (author)

Co-simulation of building energy simulation and computational fluid dynamics for whole-building heat, air and moisture engineering

NARCIS (Netherlands)

Mirsadeghi, M.

2011-01-01

Building performance simulation (BPS) is widely applied to analyse heat, air and moisture (HAM) related issues in the indoor environment such as energy consumption, thermal comfort, condensation and mould growth. The uncertainty associated with such simulations can be high, and incorrect simulation

Integration of Building energy and energy supply simulations for low-energy district heating supply to energy-efficient buildings

DEFF Research Database (Denmark)

Dalla Rosa, Alessandro

2012-01-01

The future will demand implementation of C02 neutral communities, the consequences being a far more complex design of the whole energy system, since the future energy infrastructures will be dynamic and climate responsive systems. Software able to work with such level of complexity is at present...... a missing link in the development. In this paper is demonstrated how a link between a dynamic Building Simulation Programme (BSP) and a simulation program for District Heating (DH) networks can give important information during the design phase. By using a BSP it is possible to analyze the influence...... of the human behaviour regarding the building and link the results to the simulation program for DH networks. The results show that human behaviour can lead to 50% higher heating demand and 60% higher peak loads than expected according to reference values in standardized calculation of energy demand...

The economics of supplying the supplementary heat in a closed loop water source heat pump system

International Nuclear Information System (INIS)

Johnson, R.P.; Bartkus, V.E.; Singh, J.B.

1993-01-01

The paper describes the details of a research and demonstration project that will be completed in August 1992 at a healthcare facility in northeastern Pennsylvania. The purpose of the project is to compare the economics of several methods of supplying the supplementary heating in a facility served by a closed loop water source heat pump system. The systems being tested include a storage hot water tank with electric resistance heaters and three air source heat pumps that have the ability to supply the same heat during on-peak hours as well as off-peak hours. The paper compares the projected operating costs of the following: (1) Gas boiler supplying the supplementary heat. (2) Stored hot water supplying the supplementary heat which is generated and stored during off-peak hours using resistance heat on PP ampersand L's offpeak rate. (3) Stored hot water supplying the supplementary heat generated during off-peak hours using the air source heat pumps on PP ampersand L's off-peak rate. (4) Hot water generated by the air source heat pumps supplying the supplementary loop heating on PP ampersand L's general service and time-of-day electric rates. It is generally known in the HVAC industry that a closed loop water source heat pump system can provide one of the most efficient means of space conditioning to a building with high internal gains by transferring the excess heat available in one part of the building to another part of the building where it may be needed for heating. The following flow diagram depicts the relationship of the air source heat pumps with the storage tanks and the building closed water loop

Solar heating and hot water system installed at office building, One Solar Place, Dallas, Texas

Science.gov (United States)

1980-01-01

A solar heating on cooling system is described which is designed to provide 87 percent of the space heating needs, 100 percent of the potable hot water needs and is sized for future absorption cooling. The collection subsystem consists of 28 solargenics, series 76, flat plate collectors with a total area of 1,596 square feet. The solar loop circulates an ethylene glyco water solution through the collectors into a hot water system exchanger. The water storage subsystem consists of a heat exchanger, two 2,300 gallon concrete hot water storage tanks with built in heat exchangers and a back-up electric boiler. The domestic hot water subsystem sends hot water to the 10,200 square feet floor area office building hot water water fixtures. The building cold water system provides make up to the solar loop, the heating loop, and the hot water concrete storage tanks. The design, construction, cost analysis, operation and maintenance of the solar system are described.

Sizing Combined Heat and Power Units and Domestic Building Energy Cost Optimisation

OpenAIRE

Dongmin Yu; Yuanzhu Meng; Gangui Yan; Gang Mu; Dezhi Li; Simon Le Blond

2017-01-01

Many combined heat and power (CHP) units have been installed in domestic buildings to increase energy efficiency and reduce energy costs. However, inappropriate sizing of a CHP may actually increase energy costs and reduce energy efficiency. Moreover, the high manufacturing cost of batteries makes batteries less affordable. Therefore, this paper will attempt to size the capacity of CHP and optimise daily energy costs for a domestic building with only CHP installed. In this paper, electricity ...

Heat pumps in urban space heating systems: Energy and environmental aspects

International Nuclear Information System (INIS)

Carlini, M.; Impero Abenavoli, R.; Rome Univ. La Sapienza

1991-01-01

A statistical survey is conducted of air pollution in the city of Rome (Italy) due to conventional building space heating systems burning fossil fuels. The survey identifies the annual consumption of the different fuels and the relative amounts of the various pollutants released into the atmosphere by the heating plants, e.g., sulfur and nitrogen oxides, carbon monoxide, etc. Comparisons are then made between the ratios of urban heating plant air pollutants produced per tonne of fuel employed and those for ENEL (Italian National Electricity Board) coal, oil and natural gas fired power plants, in order to demonstrate the better environmental performances of the utility operated energy plants. The building space heating system energy consumption and pollution data are then used in a cost benefit analysis favouring the retrofitting of conventional heating systems with heat pump systems to obtain substantial reductions in energy consumption, heating bills and urban air pollution. The use of readily available, competitively priced and low polluting (in comparison with fuel oil and coal) methane as the energy source for space heating purposes is recommended. The paper also notes the versatility of the heat pump systems in that they could also be used for summer air conditioning

The role of the design and operation of individual heating systems for the energy retrofits of residential buildings

International Nuclear Information System (INIS)

Terés-Zubiaga, J.; Campos-Celador, A.; González-Pino, I.; Diarce, G.

2016-01-01

Highlights: • Thermal renovation of buildings is analysed by dynamic simulation. • Different envelope and individual heating options are considered. • Temperature set point plays the most important role in the energy consumption. • Condensing boilers increase 10% the energy savings compared to regular ones. • The rebound effect can cause significant differences on energy consumption. - Abstract: The feasibility of individual natural gas fired boiler-based heating systems in the retrofitting of buildings constructed in the 50–60 s in Bilbao (northern Spain) is evaluated in this paper. A holistic approach through dynamic simulations using TRNSYS is employed for the purpose. An existing dwelling previously monitored and used to validate the model applied is selected as a case study. 54 different scenarios are evaluated, which arise from the combination of 3 different envelope options, 2 types of heat production units, 3 heat production temperatures and 3 comfort temperature set-points. The cases are evaluated in terms of energy results, economic aspects, and the influence of user behaviour. Regarding the latter, the influence of the potential rebound effect is also evaluated. The results show energy savings nearby 10% when condensing boilers are compared with high efficiency boilers. In relation to hot water production temperature, energy savings between 5 and 10% are found when the temperature is lowered from 60 to 50 °C. The greatest impact on energy consumption is related to the occupants’ behaviour: reductions up to 89% are achieved if the indoor temperature set-point is lowered 2 °C. This is reinforced with the results related to the rebound effect, which show significant differences on energy consumption values. These evidences demonstrate that the user behaviour is an essential feature to be considered in studies regarding buildings energy performance. As a consequence, the holistic approach herein employed emerges as a key tool to be applied in

Change in heat load profile for typical Danish multi-storey buildings when energy-renovated and supplied with low-temperature district heating

DEFF Research Database (Denmark)

Harrestrup, Maria; Svendsen, Svend

2013-01-01

) supply. When end-use-savings are implemented in buildings concurrent with the application of low-temperature district heating (DH) (supply=55°C, return=25°C) the heat demand profiles for the individual buildings will change. The reduction in peak load is important since it is the dimensioning foundation...... for the future DH-systems and in order to avoid oversized RE-based capacity, a long-term perspective needs to be taken. The results show that it is possible to design the DH-plants based on an average value of the 5 days with highest daily average loads without compromising with indoor thermal comfort. Applying...

Solar heating and hot water system installed at office building, One Solar Place, Dallas, Texas. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

This document is the Final Report of the Solar Energy System Installed at the First Solar Heated Office Building, One Solar Place, Dallas, Texas. The Solar System was designed to provide 87 percent of the space heating needs, 100 percent of the potable hot water needs and is sized for future absorption cooling. The collection subsystem consists of 28 Solargenics, series 76, flat plate collectors with a total area of 1596 square feet. The solar loop circulates an ethylene glycol-water solution through the collectors into a hot water system heat exchanger. The hot water storage subsystem consists of a heat exchanger, two 2300 gallon concrete hot water storage tanks with built in heat exchangers and a back-up electric boiler. The domestic hot water subsystem sends hot water to the 10,200 square feet floor area office building hot water fixtures. The building cold water system provides make-up to the solar loop, the heating loop, and the hot water concrete storage tanks. The design, construction, cost analysis, operation and maintenance of the solar system are described. The system became operational July 11, 1979.

Building Fit-For-Purpose Land Administration Systems

DEFF Research Database (Denmark)

Lemmen, Christiaan; Enemark, Stig; McLaren, Robin

2016-01-01

New solutions in land administration are required that can deliver security of tenure for all, are affordable and can be quickly developed and incrementally improved over time. The Fit-For-Purpose (FFP) approach to land administration has emerged to meet these simple, but challenging requirements...... administration following the FFP principles for building the spatial framework. The Social Tenure Domain Model (STDM) is recommended.  ‘Review (Conversion)’ means assessing the evidence of rights and any possible out-standing claims and when conditions are met, the security of the rights will be increased...... of formality, legality and technical accuracy. Such flexibility also relates to the recordation that should be organised at various levels rather than through one central register. The land administration system can then be upgraded and incrementally improved over time in response to social and legal needs...

Leverkusen revenue office building with geothermal and district heating; Finanzamt Leverkusen setzt auf Geothermie und Fernwaerme

Energy Technology Data Exchange (ETDEWEB)

Keveloh, Holger [Depenbrock Systembau GmbH und Co. KG, Bielefeld (Germany); Paterak, Anette; Wiemer, Bianca; Foerschler, Eberhard [Assmann Beraten+Planen GmbH, Dortmund (Germany)

2011-07-01

Efficient air conditioning of office buildings is possible with concrete core activation via a geothermal heat pump. The new building of the revenue office at Leverkusen will use this technology. (orig.)

Economic analysis of wind-powered farmhouse and farm building heating systems. Final report

Energy Technology Data Exchange (ETDEWEB)

Stafford, R.W.; Greeb, F.J.; Smith, M.F.; Des Chenes, C.; Weaver, N.L.

1981-01-01

The study evaluated the break-even values of wind energy for selected farmhouses and farm buildings focusing on the effects of thermal storage on the use of WECS production and value. Farmhouse structural models include three types derived from a national survey - an older, a more modern, and a passive solar structure. The eight farm building applications that were analyzed include: poultry-layers, poultry-brooding/layers, poultry-broilers, poultry-turkeys, swine-farrowing, swine-growing/finishing, dairy, and lambing. These farm buildings represent the spectrum of animal types, heating energy use, and major contributions to national agricultural economic values. All energy analyses were based on hour-by-hour computations which allowed for growth of animals, sensible and latent heat production, and ventilation requirements. Hourly or three-hourly weather data obtained from the National Climatic Center was used for the nine chosen analysis sites, located throughout the United States and corresponding to regional agricultural production centers.

Effect of length of measurement period on accuracy of predicted annual heating energy consumption of buildings

International Nuclear Information System (INIS)

Cho, Sung-Hwan; Kim, Won-Tae; Tae, Choon-Soeb; Zaheeruddin, M.

2004-01-01

This study examined the temperature dependent regression models of energy consumption as a function of the length of the measurement period. The methodology applied was to construct linear regression models of daily energy consumption from 1 day to 3 months data sets and compare the annual heating energy consumption predicted by these models with actual annual heating energy consumption. A commercial building in Daejon was selected, and the energy consumption was measured over a heating season. The results from the investigation show that the predicted energy consumption based on 1 day of measurements to build the regression model could lead to errors of 100% or more. The prediction error decreased to 30% when 1 week of data was used to build the regression model. Likewise, the regression model based on 3 months of measured data predicted the annual energy consumption within 6% of the measured energy consumption. These analyses show that the length of the measurement period has a significant impact on the accuracy of the predicted annual energy consumption of buildings

Feasibility of a single-purpose reactor plant for district heating in Finland

International Nuclear Information System (INIS)

Tarjanne, R.; Vuori, S.; Eerikaeinen, L.; Saukkoriipi, L.

A feasibility study of a single-purpose reactor for district heating is presented. The reactor chosen is of an ordinary pressurized water reactor type with a thermal output of 100 to 200 MW. Primary circuit steam generators employed in ordinary PWR's are replaced by water-water heat exchangers. For safety reasons an intermediate circuit separates the primary from the network water. The conditions of the district heating systems in Finland were taken into account, which led to the choice of an average temperature of 160 0 C for the reactor coolant and a pressure of 13.5 bar. This, coupled with minimal control requirements helped design a considerably simple reactor plant. On condition, the reactor satisfies the basic heat demand in a district heating system, the effective annual full-power operation time of the heating reactor is from 5000 h to 7000 h. Economic comparisons indicated that the heating reactor may be competitive if the operation period is of this order. As the reactor has to be sited near the heat consumption area for reasons of economy, the safety aspects are of major importance and may in themselves preclude the realization of the heating idea. (author)

Siting analysis and risk assessment for small single-purpose heating reactors

International Nuclear Information System (INIS)

Tarjanne, R.

1979-04-01

Two alternative sites both 10km away from the centre of Helsinki are considered for reactor unit sizes of 400mw and 800mw. The risks associated with a small single-purpose heating reactor is evaluated for normal operation and accident conditions. The evaluation for accident condition is performed for three characteristics accidents. Three pathways are considered in the calculation of the radiation exposure: direct external gamma dose from the release plume, direct gamma radiation from deposited activity on the ground and dose due to inhalation. The risks are compared with the risks from alternative conventional fossil fuelled district heat production methods. The results show that the heating reactor alternative causes an unsignificant risk, which is far less than the risk caused by the fossil-fuelled alternatives

The Proposed Heating and Cooling System in the CH2 Building and Its Impact on Occupant Productivity

Directory of Open Access Journals (Sweden)

Lu Aye

2012-11-01

Full Text Available Melbourne's climatic conditions demand that its buildings require both heating and cooling systems. In a multi-storey office building , however, cooling requirements will dominate. How the internal space is cooled and ventilation air is delivered will significantly impact on occupant comfort. This paper discusses the heating and cooling systems proposed for the CH2building. The paper critiques the proposed systems against previous experience, both internationally and in Australia. While the heating system employs proven technologies, less established techniques are proposed for the cooling system. Air movement in the shower towers, for example, is to be naturally induced and this has not always been successful elsewhere. Phase change material for storage of "coolth" does not appear to have been demonstrated previously in a commercial building, so the effectiveness of the proposed system is uncertain. A conventional absorption chiller backs up the untried elements of the cooling system, so that ultimately occupant comfort should not be compromised .

A Model for Optimization and Analysis of Energy Flexible Boiler Plants for Building Heating Purposes

Energy Technology Data Exchange (ETDEWEB)

Nielsen, J R

1996-05-01

This doctoral thesis presents a model for optimization and analysis of boiler plants. The model optimizes a boiler plant with respect to the annual total costs or with respect to energy consumption. The optimum solution is identified for a given number of energy carriers and defined characteristics of the heat production units. The number of heat production units and the capacity of units related to each energy carrier or the capacity of units related to the same energy carrier can be found. For a problem comprising large variation during a defined analysis period the model gives the operating costs and energy consumption to be used in an extended optimization. The model can be used to analyse the consequences with respect to costs and energy consumption due to capacity margins and shifts in the boundary conditions. The model is based on a search approach comprising an operational simulator. The simulator is based on a marginal cost method and dynamic programming. The simulation is performed on an hourly basis. A general boiler characteristic representation is maintained by linear energy or cost functions. The heat pump characteristics are represented by tabulated performance and efficiency as function of state and nominal aggregate capacities. The simulation procedure requires a heat load profile on an hourly basis. The problem of the presence of capacity margins in boiler plants is studied for selected cases. The single-boiler, oil-fired plant is very sensitive to the magnitude of the losses present during burner off-time. For a plant comprising two oil-fired burners, the impact of a capacity margin can be dampened by the selected capacity configuration. The present incentive, in Norway, to install an electric element boiler in an oil-fired boiler plant is analysed. 77 refs., 74 figs., 12 tabs.

Evaluating the use heat pipe for dedicated ventilation of office buildings in Hong Kong

Energy Technology Data Exchange (ETDEWEB)

Zhang Lian [Department of Building Services Engineering, Hong Kong Polytechnic University, Hung Hom (Hong Kong); Lee, W.L., E-mail: bewll@polyu.edu.h [Department of Building Services Engineering, Hong Kong Polytechnic University, Hung Hom (Hong Kong)

2011-04-15

Research highlights: {yields} Heat pipe dedicated for outdoor air treatment (HPDV system) was investigated. {yields} Investigations were based on cooling demand of 10 existing office buildings in HK. {yields} HPDV system could save energy use for 70% of the air-conditioned hours. {yields} HPDV system could save 1.2% to 7.9% of annual energy use for air-conditioning. {yields} Heat pipe of 57% effectiveness is the best in achieving energy saving objectives. -- Abstract: Recent research studies advocates decoupling dehumidification from cooling to improve indoor air quality and reduce energy consumption. The feasible use of heat pipe at the air handler dedicated for outdoor air treatment (HPDV system) in accomplishing this objective is investigated in this study. To evaluate the performance and the energy saving potential of the proposed HPDV system, the design parameters of 75 Grade A office buildings in Hong Kong were collected. Ten representative buildings were subsequently identified for further study to achieve a confidence level of 95%. The annual cooling load profiles of the 10 representative buildings were simulated by the use of HTB2. Based on the realistic cooling load profiles and the heat pipes of effectiveness 0.35-0.6, the proposed HPDV system in achieving the intended objectives were evaluated. It was found that the savings for the 10 representative buildings were comparable. The reduction in cooling and reheating energy was between 23 and 44 kWh/m{sup 2}, which corresponds to 1.2% and 7.9% saving in annual energy use for air-conditioning. The results indicate that HP of different effectiveness can be applied to save energy for over 70% of the air-conditioned hours; of which only 0.03-6.3% of the time the decoupling objective cannot be achieved (abbreviated as NHRS). Based on the results of the study, a simplified model relating NHRS with heat pipe effectiveness has been established. The model can help designers more quickly determine how NHRS can be

Building physics. Heat transport - humidity - sound. 4. new rev. ed. Bauphysik. Waermetransport - Feuchtigkeit - Schall

Energy Technology Data Exchange (ETDEWEB)

Berber, J. (Fachhochschule Coburg (Germany))

1994-01-01

Numerous factors must be considered when planning buildings. While the buildings must be protected from fire, from the penetration of moisture, and from vibrations, the occupants must be protected from extreme temperature variations, insalubrious room air conditions, and undesirable noises. Certain matter constants, layer thicknesses, component sizes, room and building dimensions must be known for establishment of the required heat, moisture and sound protection rules. This manual discusses the relevant physical aspects based on fundamental knowledge. Application-oriented examples and problem definitions facilitate access to the practice of building construction. (BWI)

Communal heating statistics for seven selected sites. Heating energy consumption, heating cost, and carbon dioxide emissions of domestic buildings with central heating systems. Final report; Kommunale Heizspiegel fuer sieben ausgewaehlte Standorte. Heizenergieverbrauch, Heizkosten und CO{sub 2}-Emissionen von zentralbeheizten Wohngebaeuden. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Bade, M. [comp.

1999-10-01

Heating staticstics help to define potential energy savings, informing building owners, landlords and tenants on specific energy consumption and specific heating cost of centrally heated multiple dwellings and enabling them a comparison with other buildings of a community. Data are evaluated separately for natural gas, heating oil and district heat. Statistics are presented for the cities of Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden and Esslingen. The heating statistics were established in cooperation with heat metering and billing services and building societies in order to obtain a wide data base. [German] Heizpiegel koennen ein wirksames Instrument zur Ausschoepfung des vorhandenen Energiesparpotentials im Gebaeudebestand sein. Sie informieren Gebaeudeeigentuemer, Vermieter und Mieter ueber den spezifischen Heizenergieverbrauch und die spezifischen Heizkosten von zentralbeheizten Mehrfamiliengebaeuden und ermoeglichen gleichzeitig einen Vergleich mit dem uebrigen Gebaeudebestand einer Kommune bzw. Stadt. Die zur Erstellung von Heizspiegeln erforderliche Datenauswertung erfolgt getrennt nach den Energietraegern Erdgas, Heizoel und Fernwaerme. Im Rahmen des Projektes wurden fuer die Staedte Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden und Esslingen Heizspiegel erstellt. Bei der Erstellung der Heizspiegel konnte durch die Mitarbeit mehrerer Heizkosten-Verteilerfirmen und Wohnungsgesellschaften auf eine relativ breite Datenbasis zurueckgegriffen werden. (orig.)

Experimental validation of the buildings energy performance (PEC assessment methods with reference to occupied spaces heating

Directory of Open Access Journals (Sweden)

Cristian PETCU

2010-01-01

Full Text Available This paper is part of the series of pre-standardization research aimed to analyze the existing methods of calculating the Buildings Energy Performance (PEC in view of their correction of completing. The entire research activity aims to experimentally validate the PEC Calculation Algorithm as well as the comparative application, on the support of several case studies focused on representative buildings of the stock of buildings in Romania, of the PEC calculation methodology for buildings equipped with occupied spaces heating systems. The targets of the report are the experimental testing of the calculation models so far known (NP 048-2000, Mc 001-2006, SR EN 13790:2009, on the support provided by the CE INCERC Bucharest experimental building, together with the complex calculation algorithms specific to the dynamic modeling, for the evaluation of the occupied spaces heat demand in the cold season, specific to the traditional buildings and to modern buildings equipped with solar radiation passive systems, of the ventilated solar space type. The schedule of the measurements performed in the 2008-2009 cold season is presented as well as the primary processing of the measured data and the experimental validation of the heat demand monthly calculation methods, on the support of CE INCERC Bucharest. The calculation error per heating season (153 days of measurements between the measured heat demand and the calculated one was of 0.61%, an exceptional value confirming the phenomenological nature of the INCERC method, NP 048-2006. The mathematical model specific to the hourly thermal balance is recurrent – decisional with alternating paces. The experimental validation of the theoretical model is based on the measurements performed on the CE INCERC Bucharest building, within a time lag of 57 days (06.01-04.03.2009. The measurements performed on the CE INCERC Bucharest building confirm the accuracy of the hourly calculation model by comparison to the values

Comparison of electricity and heat production in combined and single-purpose systems against the background of energy saving by means of thermal insulation. Pt. 1. System comparison and general results; Vergleich der Strom- und Heizenergieerzeugung in gekoppelten und ungekoppelten Anlagen vor dem Hintergrund der Einsparmoeglichkeiten durch Waermedaemmung. T. 1. Systemvergleich und allgemeine Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Damberger, S.; Guenther, M.; Kluender, M.; Moeller, K.P.; Wenk, N.

1994-06-01

The study comprises investigations for the purpose of increasing the generation of electricity and heat in dual-purpose power plants and for promoting thermal insulation of buildings: Methods for comparatiave calculations; economic aspects; separate generation of electric power and heat; cogeneration of electric power and heat; economic efficiency of thermal insulation measures in domestic buildings; comparison of results. (HW) [Deutsch] Die Studie umfasst Untersuchungen zur Erhoehung des Anteils der gekoppelten Erzeugung von Strom und Waerme und zur vermehrten Waermedaemmung von Gebaeuden: - Methoden fuer Vergleichsrechnungen - Ekonomie - getrennte Erzeugung von Strom und Waerme - gekoppelte Erzeugung von Strom und Waerme - Wirtschaftlichkeit von Massnahmen einer Waermedaemmung von Wohngebaeuden - Vergleich der Ergebnisse. (HW)

Experiences with field tests: Ground coupled heat pumps in small residential buildings; Feldtesterfahrungen. Erdgekoppelte Waermepumpen in kleineren Wohngebaeuden

Energy Technology Data Exchange (ETDEWEB)

Wapler, Jeannette; Guenther, Danny; Miara, Marek [Fraunhofer-Institut fuer Solare Energiesysteme ISE/Thermal Systems and Buildings, Freiburg (Germany)

2012-07-01

In the context of two research projects, the Fraunhofer Institute for Solar Energy Systems (Freiburg, Federal Republic of Germany) has surveyed a large number of heat pumps in actual application. In particular, heat pumps in small residential buildings (single-family houses) were examined for new and existing buildings. In addition to the achieved performance factors the temperature profile of the heat sink and heat source was recorded. This temperature profile was evaluated separately for systems with geothermal collectors and systems with geothermal probes. The theoretical assumptions could be confirmed. Influences during the installation, commissioning and operation are identified.

Statistical models describing the energy signature of buildings

DEFF Research Database (Denmark)

Bacher, Peder; Madsen, Henrik; Thavlov, Anders

2010-01-01

Approximately one third of the primary energy production in Denmark is used for heating in buildings. Therefore efforts to accurately describe and improve energy performance of the building mass are very important. For this purpose statistical models describing the energy signature of a building, i...... or varying energy prices. The paper will give an overview of statistical methods and applied models based on experiments carried out in FlexHouse, which is an experimental building in SYSLAB, Risø DTU. The models are of different complexity and can provide estimates of physical quantities such as UA......-values, time constants of the building, and other parameters related to the heat dynamics. A method for selecting the most appropriate model for a given building is outlined and finally a perspective of the applications is given. Aknowledgements to the Danish Energy Saving Trust and the Interreg IV ``Vind i...

Roles of Urban Tree Canopy and Buildings in Urban Heat Island Effects: Parameterization and Preliminary Results

Science.gov (United States)

Loughner, Christopher P.; Allen, Dale J.; Zhang, Da-Lin; Pickering, Kenneth E.; Dickerson, Russell R.; Landry, Laura

2012-01-01

Urban heat island (UHI) effects can strengthen heat waves and air pollution episodes. In this study, the dampening impact of urban trees on the UHI during an extreme heat wave in the Washington, D.C., and Baltimore, Maryland, metropolitan area is examined by incorporating trees, soil, and grass into the coupled Weather Research and Forecasting model and an urban canopy model (WRF-UCM). By parameterizing the effects of these natural surfaces alongside roadways and buildings, the modified WRF-UCM is used to investigate how urban trees, soil, and grass dampen the UHI. The modified model was run with 50% tree cover over urban roads and a 10% decrease in the width of urban streets to make space for soil and grass alongside the roads and buildings. Results show that, averaged over all urban areas, the added vegetation decreases surface air temperature in urban street canyons by 4.1 K and road-surface and building-wall temperatures by 15.4 and 8.9 K, respectively, as a result of tree shading and evapotranspiration. These temperature changes propagate downwind and alter the temperature gradient associated with the Chesapeake Bay breeze and, therefore, alter the strength of the bay breeze. The impact of building height on the UHI shows that decreasing commercial building heights by 8 m and residential building heights by 2.5 m results in up to 0.4-K higher daytime surface and near-surface air temperatures because of less building shading and up to 1.2-K lower nighttime temperatures because of less longwave radiative trapping in urban street canyons.

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.

Tests for removal of decay heat by natural convection

International Nuclear Information System (INIS)

Kashiwagi, E.; Wataru, M.; Gomi, Y.; Hattori, Y.; Ozaki, S.

1993-01-01

Interim storage technology for spent fuel by dry storage casks have been investigated. The casks are vertically placed in a storage building. The decay heat is removed from the outer cask surface by natural convection of air entering from the building wall to the roof. The air flow pattern in the storage building was governed by the natural driving pressure difference and circulating flow. The purpose of this study is to understand the mechanism of the removal of decay heat from casks by natural convection. The simulated flow conditions in the building were assumed as a natural and forced combined convection and were investigated by the turbulent quantities near wall. (author)

Model building strategy for logistic regression: purposeful selection.

Science.gov (United States)

Zhang, Zhongheng

2016-03-01

Logistic regression is one of the most commonly used models to account for confounders in medical literature. The article introduces how to perform purposeful selection model building strategy with R. I stress on the use of likelihood ratio test to see whether deleting a variable will have significant impact on model fit. A deleted variable should also be checked for whether it is an important adjustment of remaining covariates. Interaction should be checked to disentangle complex relationship between covariates and their synergistic effect on response variable. Model should be checked for the goodness-of-fit (GOF). In other words, how the fitted model reflects the real data. Hosmer-Lemeshow GOF test is the most widely used for logistic regression model.

Study on the Development of an Optimal Heat Supply Control Algorithm for Group Energy Apartment Buildings According to the Variation of Outdoor Air Temperature

Directory of Open Access Journals (Sweden)

Dong-Kurl Kwak

2012-05-01

Full Text Available In the present study, we have developed an optimal heat supply algorithm which minimizes the heat loss through the distribution pipe line in a group energy apartment. Heating load variation of a group energy apartment building according to the outdoor air temperature was predicted by a correlation obtained from calorimetry measurements of all households in the apartment building. Supply water temperature and mass flow rate were simultaneously controlled to minimize the heat loss rate through the distribution pipe line. A group heating apartment building located in Hwaseong city, Korea, which has 1473 households, was selected as the object building to test the present heat supply algorithm. Compared to the original heat supply system, the present system adopting the proposed control algorithm reduced the heat loss rate by 10.4%.

Systems for apartment buildings heat pumps. Final report; System foer fastighetsvaermepumpar. Slutrapport

Energy Technology Data Exchange (ETDEWEB)

Aakervall, Daniel (WSP Environmental, Stockholm (Sweden)); Rogstam, Joergen; Grotherus, Maarten (Sveriges Energi- och Kylcentrum, Katrineholm (Sweden))

2009-05-15

A fast growing segment of the heat pump business is the apartment building applications. Historically the experience base related to such installations is limited. However, this application is more complex than the much more widely spread domestic applications. The core idea of the project was to generate and collect information to avoid mistakes and to encourage the heat pump technology. By interviewing the 'market' and compiling the information good recommendations has been achieved. It is of great importance to convey the best available recommendations to the installers on the market to avoid pit holes and highlight the opportunities for installers and end consumers. A website has been design and built, www.sfvp.se, which contains useful tools for installers and potential system customers. A number of calculation tools to estimate heat requirement, cost of different heating systems, primary energy need, LCC, etc. are all available. The core of the site is the database containing heat pump installations with related data of importance. The data available is such key data as performance figures, cost of installation, etc. Today 104 system installations are collected in the database and these are marked in a colour coding to indicate the quality of the input data. Installations verified with measurement are given higher significance. It has been an unexpected challenge to find documented systems, so one of the conclusions of the project is that there is a great need for further measurement on the field. More information should be directed to the customers to request such equipment when systems are installed. The database enables statistical analysis of the key figures and it can be seen that the average seasonal COP is 3.2 and there are small differences between exhaust air and ground source heat pumps. It should be emphasised that the number of installations do not give statistical confidence for all kinds of analysis yet. Field measurements in apartment

An experimental set-up to test heat-moisture exchangers

NARCIS (Netherlands)

Unal, N.; Pompe, J. C.; Holland, W. P.; Gültuna, I.; Huygen, P. E.; Jabaaij, K.; Ince, C.; Saygin, B.; Bruining, H. A.

1995-01-01

The purpose of this study was to build an experimental set-up to assess continuously the humidification, heating and resistance properties of heat-moisture exchangers (HMEs) under clinical conditions. The experimental set-up consists of a patient model, measurement systems and a ventilator. Surgical

Integrated application of combined cooling, heating and power poly-generation PV radiant panel system of zero energy buildings

Science.gov (United States)

Yin, Baoquan

2018-02-01

A new type of combined cooling, heating and power of photovoltaic radiant panel (PV/R) module was proposed, and applied in the zero energy buildings in this paper. The energy system of this building is composed of PV/R module, low temperature difference terminal, energy storage, multi-source heat pump, energy balance control system. Radiant panel is attached on the backside of the PV module for cooling the PV, which is called PV/R module. During the daytime, the PV module was cooled down with the radiant panel, as the temperature coefficient influence, the power efficiency was increased by 8% to 14%, the radiant panel solar heat collecting efficiency was about 45%. Through the nocturnal radiant cooling, the PV/R cooling capacity could be 50 W/m2. For the multifunction energy device, the system shows the versatility during the heating, cooling and power used of building utilization all year round.

Research of the Effectiveness of Using Air and Ground Low-grade Heat for Buildings Heating in Different Regions of Russia

Directory of Open Access Journals (Sweden)

Vasilyev G.P.

2016-01-01

Full Text Available The article presents the results of research on zoning of the Russian Federation based on efficiency of utilization of the low-grade heat of ground and air as well as combinations thereof for heating buildings. When modeling thermal behavior of geothermal HHS in the climatic conditions of various regions of the Russian Federation we considered the effect of long-term recovery of geothermal heat on the thermal behavior of the ground, as well as the effect of the ground pore water phase transitions on the operational efficiency of geothermal heat pump heating systems. The zoning took into account temperature drop of the ground mass caused by many years of heat recovery from the ground. Ground temperatures expected for the 5th year of geothermal HHS operation were used as design ground mass temperatures.

Model for Determining Geographical Distribution of Heat Saving Potentials in Danish Building Stock

DEFF Research Database (Denmark)

Petrovic, Stefan; Karlsson, Kenneth Bernard

2014-01-01

Since the global oil crisis in the 1970s, Denmark has followed a path towards energy independency by continuously improving its energy efficiency and energy conservation. Energy efficiency was mainly tackled by introducing a high number of combined heat and power plants in the system, while energy...... conservation was predominantly approached by implementing heat saving measures. Today, with the goal of 100% renewable energy within the power and heat sector by the year 2035, reductions in energy demand for space heating and the preparation of domestic hot water remain at the top of the agenda in Denmark....... A highly detailed model for determining heat demand, possible heat savings and associated costs in the Danish building stock is presented. Both scheduled and energy-saving renovations until year 2030 have been analyzed. The highly detailed GIS-based heat atlas for Denmark is used as a container for storing...

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.

The effect of micro air movement on the heat and moisture characteristics of building constructions

NARCIS (Netherlands)

Schijndel, van A.W.M.

2010-01-01

The research focuses on the effect of air movement through building constructions. Although the typical air movement inside building constructions is quite small (velocity is of order ~10-5 m/s), this research shows the impact on the heat and moisture characteristics. The paper presents a case study

The effect of micro air movement on the heat and moisture characteristics of building constructions

NARCIS (Netherlands)

Schijndel, van A.W.M.

2008-01-01

The research focuses on the effect of air movement through building constructions. Although the typical air movement inside building constructions is quite small (velocity is of order ~10-5 m/s), this research shows the impact on the heat and moisture characteristics. The paper presents a case study

Air Source Heat Pump a Key Role in the Development of Smart Buildings in Future Energy Systems

DEFF Research Database (Denmark)

Craciun, Vasile S.; Trifa, Viorel; Bojesen, Carsten

2012-01-01

An important challenge for energy systems today is reducing dependency on fossil fuels, while handling increasing penetration levels of intermittent renewables such as wind and solar power. The efficient consumption of energy is a vital mater for a sustainable energy system. A significant part...... of energy is used for space heating, space cooling, and domestic hot water production which are provided to residential and commercial buildings. Air source heat pumps (ASHP) are widely used conversion technologies all over the world for providing building thermal energy services as: cooling, heating......, and water heating. ASHP does not have a constant temperature for the primary source like: soil, ground water, or surface water heat pumps but still have a majority in usage. As result, laboratory experiments and tests are faced by the problem of having to handle a wide range of conditions under which...

ENERGY-EFFICIENT REGIMES FOR HEATING-SUPPLY OF THE RESIDENTIAL BUILDINGS

Directory of Open Access Journals (Sweden)

S. N. Osipov

2015-01-01

Full Text Available Rise in comfort and inhabitation safety is one of the main requirements of the general maintenance, reconstruction of the old and construction of the new residential houses. One of the essential factors of it is substitution in the household hot-water preparing sources: from the individual domestic gas  water-heaters to  the common  entire-building hot-water supply at the expense of the centralized heat supply. Extremely erratic hot-water daily consumption by tenants leads to the necessity of sharp increase in central heat-supply level during a few hours of the day, which requires a significant increase of the source heat-power. On that score, the authors propose to direct a significant part (up to 50 % of the centralized heating and ventilation heat power-consumption to the hot water preparation during the period of short-term hot water consumption peak.Substitution  of  the  individual  domestic  gas  water-heaters  with  the  common  entirebuilding hot-water supply releases a huge amount of natural gas which can be utilized not only for production of the necessary heat power but as well for electric power producing. This substitution is especially advantageous if heat-power is delivered to the residential area from a НРС where significant part of heat especially in a relatively warm season of the year is thrown out into the air. The content of the article is based on several patents received earlier.

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)

Free cooling potential of a PCM-based heat exchanger coupled with a novel HVAC system for simultaneous heating and cooling of buildings

DEFF Research Database (Denmark)

Maccarini, Alessandro; Hultmark, Göran; Bergsøe, Niels Christian

2018-01-01

. In particular, a model of a PCM-based heat exchanger was developed in this work by using the programming language Modelica. This device was designed to store cold energy during night-time and release it during daytime through the water circuit. Results for a typical office building model showed...... that the integration of free cooling devices can significantly reduce the primary energy use of the novel HVAC system. In particular, the thermal plant configuration including the PCM-based heat exchanger made it possible to almost completely avoid the use of mechanical cooling, leading to annual primary energy......This article presents a simulation-based study that estimates the primary energy use of a novel HVAC system for different configurations of a thermal plant. The main characteristic of the system is its ability to provide simultaneous heating and cooling to buildings by using a single hydronic...

Future Green Buildings

DEFF Research Database (Denmark)

Mathiesen, Brian Vad; Drysdale, David; Lund, Henrik

an energy system integration perspective, heat savings, electricity savings, and user behavioural aspects as well as energy storage and household level flexibility. Many reports on green or sustainable buildings focus only on savings levels and disregard the cost of renewable energy production. Some reports......Efficient buildings are essential for an affordable Danish energy supply in 2050. The purpose of this report is to describe the contribution and role of the building sector in a 100% renewable energy future, as well as the transitions that are necessary in the building sector to support this change....... The report builds on a literature review encompassing more than 50 reports and research papers over the last 10 years and more than a two decades knowledge about the interactions between different components of the energy sector. The review has been focused on aspects such as cost-effective solutions from...

Empirical Validation of Heat Transfer Performance Simulation of Graphite/PCM Concrete Materials for Thermally Activated Building System

Directory of Open Access Journals (Sweden)

Jin-Hee Song

2017-01-01

Full Text Available To increase the heat capacity in lightweight construction materials, a phase change material (PCM can be introduced to building elements. A thermally activated building system (TABS with graphite/PCM concrete hollow core slab is suggested as an energy-efficient technology to shift and reduce the peak thermal load in buildings. An evaluation of heat storage and dissipation characteristics of TABS in graphite/PCM concrete has been conducted using dynamic simulations, but empirical validation is necessary to acceptably predict the thermal behavior of graphite/PCM concrete. This study aimed to validate the thermal behavior of graphite/PCM concrete through a three-dimensional transient heat transfer simulation. The simulation results were compared to experimental results from previous studies of concrete and graphite/PCM concrete. The overall thermal behavior for both materials was found to be similar to experiment results. Limitations in the simulation modeling, which included determination of the indoor heat transfer coefficient, assumption of constant thermal conductivity with temperature, and assumption of specimen homogeneity, led to slight differences between the measured and simulated results.

Assessment of Thermal Comfort in a Building Heated with a Tiled Fireplace with the Function of Heat Accumulation

Science.gov (United States)

Telejko, Marek; Zender-Świercz, Ewa

2017-10-01

Thermal comfort determines the state of satisfaction of a person or group of people with thermal conditions of the environment in which the person or group of persons is staying. This state of satisfaction depends on the balance between the amount of heat generated by the body’s metabolism, and the dissipation of heat from the body to the surrounding environment. Due to differences in body build, metabolism, clothing etc. individuals may feel the parameters of the environment in which they are staying differently. Therefore, it is impossible to ensure the thermal comfort of all users of the room. However, properly designed building systems (heating, ventilation, air conditioning) allow for creating optimal thermal conditions that will evaluated positively by the vast majority of users. Due to the fact that currently we spend even 100% of the day indoors, the subject becomes extremely important. The article presents the evaluation of thermal comfort in rooms heated with a tiled fireplace with the function of accumulation of heat using the PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied) indices. It also presents the results of studies, on the quality of the micro-climate in such spaces. The system of heating premises described in the article is not a standard solution, but is now more and more commonly used as a supplement to the heating system, or even as a primary heating system in small objects, e.g. single-family houses, seasonal homes, etc. The studies comprised the measurements and analysis of typical internal micro-climate parameters: temperature, relative humidity and CO2 concentration. The results obtained did not raise any major reservations. In order to fully assess the conditions of use, the evaluation of thermal comfort of the analyzed rooms was made. Therefore, additionally the temperature of radiation of the surrounding areas, and the insulation of the users’ clothing was determined. Based on the data obtained, the PPD and PMV

Primary energy savings using heat storage for biomass heating systems

Directory of Open Access Journals (Sweden)

Mitrović Dejan M.

2012-01-01

Full Text Available District heating is an efficient way to provide heat to residential, tertiary and industrial users. The heat storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the heat storage unit makes it possible to heat even when the boiler is not working, thus increasing the heating efficiency. In order to save primary energy (fuel, the boiler operates on nominal load every time it is in operation (for the purpose of this research. The aim of this paper is to analyze the water temperature variation in the heat storage, depending on the heat load and the heat storage volume. Heat load is calculated for three reference days, with average daily temperatures from -5 to 5°C. The primary energy savings are also calculated for those days in the case of using heat storage in district heating.[Projekat Ministarstva nauke Republike Srbije, br. TR 33051: The concept of sustainable energy supply of settlements with energy efficient buildings

General-purpose heat source development. Phase II: conceptual designs

International Nuclear Information System (INIS)

Snow, E.C.; Zocher, R.W.; Grinberg, I.M.; Hulbert, L.E.

1978-11-01

Basic geometric module shapes and fuel arrays were studied to determine how well they could be expected to meet the General Purpose Heat Source (GPHS) design requirements. Seven conceptual designs were selected, detailed drawings produced, and these seven concepts analyzed. Three of these design concepts were selected as GPHS Trial Designs to be reanalyzed in more detail and tested. The geometric studies leading to the selection of the seven conceptual designs, the analyses of these designs, and the selection of the three trial designs are discussed

Urban weather data and building models for the inclusion of the urban heat island effect in building performance simulation.

Science.gov (United States)

Palme, M; Inostroza, L; Villacreses, G; Lobato, A; Carrasco, C

2017-10-01

This data article presents files supporting calculation for urban heat island (UHI) inclusion in building performance simulation (BPS). Methodology is used in the research article "From urban climate to energy consumption. Enhancing building performance simulation by including the urban heat island effect" (Palme et al., 2017) [1]. In this research, a Geographical Information System (GIS) study is done in order to statistically represent the most important urban scenarios of four South-American cities (Guayaquil, Lima, Antofagasta and Valparaíso). Then, a Principal Component Analysis (PCA) is done to obtain reference Urban Tissues Categories (UTC) to be used in urban weather simulation. The urban weather files are generated by using the Urban Weather Generator (UWG) software (version 4.1 beta). Finally, BPS is run out with the Transient System Simulation (TRNSYS) software (version 17). In this data paper, four sets of data are presented: 1) PCA data (excel) to explain how to group different urban samples in representative UTC; 2) UWG data (text) to reproduce the Urban Weather Generation for the UTC used in the four cities (4 UTC in Lima, Guayaquil, Antofagasta and 5 UTC in Valparaíso); 3) weather data (text) with the resulting rural and urban weather; 4) BPS models (text) data containing the TRNSYS models (four building models).

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

Heat transfer characteristics of building walls using phase change material

Science.gov (United States)

Irsyad, M.; Pasek, A. D.; Indartono, Y. S.; Pratomo, A. W.

2017-03-01

Minimizing energy consumption in air conditioning system can be done with reducing the cooling load in a room. Heat from solar radiation which passes through the wall increases the cooling load. Utilization of phase change material on walls is expected to decrease the heat rate by storing energy when the phase change process takes place. The stored energy is released when the ambient temperature is low. Temperature differences at noon and evening can be utilized as discharging and charging cycles. This study examines the characteristics of heat transfer in walls using phase change material (PCM) in the form of encapsulation and using the sleeve as well. Heat transfer of bricks containing encapsulated PCM, tested the storage and released the heat on the walls of the building models were evaluated in this study. Experiments of heat transfer on brick consist of time that is needed for heat transfer and thermal conductivity test as well. Experiments were conducted on a wall coated by PCM which was exposed on a day and night cycle to analyze the heat storage and heat release. PCM used in these experiments was coconut oil. The measured parameter is the temperature at some points in the brick, walls and ambient temperature as well. The results showed that the use of encapsulation on an empty brick can increase the time for thermal heat transfer. Thermal conductivity values of a brick containing encapsulated PCM was lower than hollow bricks, where each value was 1.3 W/m.K and 1.6 W/m.K. While the process of heat absorption takes place from 7:00 am to 06:00 pm, and the release of heat runs from 10:00 pm to 7:00 am. The use of this PCM layer can reduce the surface temperature of the walls of an average of 2°C and slows the heat into the room.

Users of electric heating rewarded

Energy Technology Data Exchange (ETDEWEB)

Haapakoski, M. [ed.

1998-07-01

When the building industry plunged into the deep recession of the early 1990s this did not paralyse research and development work on electric heating. In fact, IVO and power companies launched the `Electrically Heated Homes in the New Millennium` project in 1992. Its purpose was to verify the efficiency, energy economy and residential comfort of model systems using state-of-the-art electric heating technology. The research project launched six years ago is now nearing completion. Its findings indicate that electricity brings ever more unparalleled benefits when it is used for heating. These benefits involve residential comfort, ease of use and economy

Method for reducing excess heat supply experienced in typical Chinese district heating systems by achieving hydraulic balance and improving indoor air temperature control at the building level

DEFF Research Database (Denmark)

Zhang, Lipeng; Gudmundsson, Oddgeir; Thorsen, Jan Eric

2016-01-01

A common problem with Chinese district heating systems is that they supply more heat than the actual heat demand. The reason for this excess heat supply is the general failure to use control devices to adjust the indoor temperature and flow in the building heating systems in accordance with the a......A common problem with Chinese district heating systems is that they supply more heat than the actual heat demand. The reason for this excess heat supply is the general failure to use control devices to adjust the indoor temperature and flow in the building heating systems in accordance...... with the actual heat demand. This results in 15-30% of the total supplied heat being lost. This paper proposes an integrated approach that aims to reduce the excess heat loss by introducing pre-set thermostatic radiator valves combined with automatic balancing valves. Those devices establish hydraulic balance...... that once the hydraulic balance is achieved and indoor temperatures are controlled with this integrated approach, 17% heat savings and 42.8% pump electricity savings can be achieved. The energy savings will also have a positive environmental effect with seasonal reductions of 11 kg CO2, 0.1 kg SO2, and 0...

Integration of a magnetocaloric heat pump in a low-energy residential building

DEFF Research Database (Denmark)

Johra, Hicham; Filonenko, Konstantin; Heiselberg, Per

2018-01-01

magnetocaloric effect of a solid refrigerant to build a cooling/heating cycle. It has the potential for high coefficient of performance, more silent operation and efficient part-load control. After presenting the operation principles of the magnetocaloric device and the different models used in the current...

Cooling energy efficiency and classroom air environment of a school building operated by the heat recovery air conditioning unit

International Nuclear Information System (INIS)

Wang, Yang; Zhao, Fu-Yun; Kuckelkorn, Jens; Liu, Di; Liu, Li-Qun; Pan, Xiao-Chuan

2014-01-01

The recently-built school buildings have adopted novel heat recovery ventilator and air conditioning system. Heat recovery efficiency of the heat recovery facility and energy conservation ratio of the air conditioning unit were analytically modeled, taking the ventilation networks into account. Following that, school classroom displacement ventilation and its thermal stratification and indoor air quality indicated by the CO 2 concentration have been numerically modeled concerning the effects of delivering ventilation flow rate and supplying air temperature. Numerical results indicate that the promotion of mechanical ventilation rate can simultaneously boost the dilution of indoor air pollutants and the non-uniformity of indoor thermal and pollutant distributions. Subsequent energy performance analysis demonstrates that classroom energy demands for ventilation and cooling could be reduced with the promotion of heat recovery efficiency of the ventilation facility, and the energy conservation ratio of the air conditioning unit decreases with the increasing temperatures of supplying air. Fitting correlations of heat recovery ventilation and cooling energy conservation have been presented. - Highlights: • Low energy school buildings and classroom environment. • Heat recovery facility operating with an air conditioning unit. • Displacement ventilation influenced by the heat recovery efficiency. • Energy conservation of cooling and ventilation through heat recovery. • Enhancement of classroom environment with reduction of school building energy

A neural network controller for hydronic heating systems of solar buildings.

Science.gov (United States)

Argiriou, Athanassios A; Bellas-Velidis, Ioannis; Kummert, Michaël; André, Philippe

2004-04-01

An artificial neural network (ANN)-based controller for hydronic heating plants of buildings is presented. The controller has forecasting capabilities: it includes a meteorological module, forecasting the ambient temperature and solar irradiance, an indoor temperature predictor module, a supply temperature predictor module and an optimizing module for the water supply temperature. All ANN modules are based on the Feed Forward Back Propagation (FFBP) model. The operation of the controller has been tested experimentally, on a real-scale office building during real operating conditions. The operation results were compared to those of a conventional controller. The performance was also assessed via numerical simulation. The detailed thermal simulation tool for solar systems and buildings TRNSYS was used. Both experimental and numerical results showed that the expected percentage of energy savings with respect to a conventional controller is of about 15% under North European weather conditions.

Simultaneous Heat and Mass Transfer Model for Convective Drying of Building Material

Science.gov (United States)

Upadhyay, Ashwani; Chandramohan, V. P.

2018-04-01

A mathematical model of simultaneous heat and moisture transfer is developed for convective drying of building material. A rectangular brick is considered for sample object. Finite-difference method with semi-implicit scheme is used for solving the transient governing heat and mass transfer equation. Convective boundary condition is used, as the product is exposed in hot air. The heat and mass transfer equations are coupled through diffusion coefficient which is assumed as the function of temperature of the product. Set of algebraic equations are generated through space and time discretization. The discretized algebraic equations are solved by Gauss-Siedel method via iteration. Grid and time independent studies are performed for finding the optimum number of nodal points and time steps respectively. A MATLAB computer code is developed to solve the heat and mass transfer equations simultaneously. Transient heat and mass transfer simulations are performed to find the temperature and moisture distribution inside the brick.

Energy system investment model incorporating heat pumps with thermal storage in buildings and buffer tanks

DEFF Research Database (Denmark)

Hedegaard, Karsten; Balyk, Olexandr

2013-01-01

Individual compression heat pumps constitute a potentially valuable resource in supporting wind power integration due to their economic competitiveness and possibilities for flexible operation. When analysing the system benefits of flexible heat pump operation, effects on investments should...... be taken into account. In this study, we present a model that facilitates analysing individual heat pumps and complementing heat storages in integration with the energy system, while optimising both investments and operation. The model incorporates thermal building dynamics and covers various heat storage...... of operating heat pumps flexibly. This includes prioritising heat pump operation for hours with low marginal electricity production costs, and peak load shaving resulting in a reduced need for peak and reserve capacity investments....

Heat of fusion storage systems for combined solar systems in low energy buildings

DEFF Research Database (Denmark)

Schultz, Jørgen Munthe; Furbo, Simon

2004-01-01

Solar heating systems for combined domestic hot water and space heating has a large potential especially in low energy houses where it is possible to take full advantage of low temperature heating systems. If a building integrated heating system is used – e.g. floor heating - the supply temperature...... from solid to liquid form (Fig. 1). Keeping the temperature as low as possible is an efficient way to reduce the heat loss from the storage. Furthermore, the PCM storage might be smaller than the equivalent water storage as more energy can be stored per volume. If the PCM further has the possibility...... systems through further improvement of water based storages and in parallel to investigate the potential of using storage designs with phase change materials, PCM. The advantage of phase change materials is that large amounts of energy can be stored without temperature increase when the material is going...

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings

DEFF Research Database (Denmark)

Harrestrup, Maria; Svendsen, S.

2014-01-01

is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized......The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce...... the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper...

Building heating technology in Smart Home using PI System management tools

Directory of Open Access Journals (Sweden)

Jan Vanus

2016-03-01

Full Text Available For comfortable remote monitoring of some operational and technical functions inside own Smart Home building, it is possible to use a lot of useful programmes and tools. However, not each programme or tool is suited to this purpose, or it does not offer required functionality. The aim of this paper is to describe using an appropriate software tool of PI System for a real-time monitoring of acquired data from real technology parts located at a training centre of the Moravian-Silesian Wood Cluster. Then a superior system including applications of PI Coresight and PI ProcessBook is used for analysis and processing of these acquired data (e.g. by using the Dynamic Time Warping method for specific technological quantities. Each application has own advantages and disadvantages, which are evaluated in conjunction with possibilities of manipulating the data. In an experimental part, there are also applied a technological communication standard of BACnet to controlling heating, cooling and forced ventilation, and a software tool of DESIGO Insight for visualising the data in forms of tables, multi-layer graphs, and screens for a certain technology.

Experimental characterization, modeling and simulation of a wood pellet micro-combined heat and power unit used as a heat source for a residential building

Energy Technology Data Exchange (ETDEWEB)

Thiers, Stephane; Aoun, Bernard; Peuportier, Bruno [MINES ParisTech, CEP - Centre Energetique et Procedes, 60 Boulevard St Michel, 75272 Paris Cedex 06 (France)

2010-06-15

Cogeneration provides heat and power in a more efficient way than separate production. Micro-cogeneration (micro-CHP) is an emerging solution for the improvement of energy and environmental assessments of residential buildings. A wood pellet Stirling engine micro-CHP unit has been studied in order to characterize its annual performance when integrated to a building. First, through a test bench experiment, both transient and steady state behaviors of the micro-CHP unit have been characterized and modeled. Then a more complete model representing a hot water and heating system including the micro-CHP unit and a stratified storage tank has been carried out. This model has been coupled to a building model. A sensitivity analysis by simulation shows that the dimensioning of different elements of the system strongly influences its global energy performance. (author)

Method for achieving hydraulic balance in typical Chinese building heating systems by managing differential pressure and flow

DEFF Research Database (Denmark)

Zhang, Lipeng; Xia, Jianjun; Thorsen, Jan Eric

2017-01-01

to a lack of pressure and flow control. This study investigated using pre-set radiator valves combined with differential pressure (DP) controllers to achieve hydraulic balance in building distribution systems, and consequently save energy and reduce the emissions. We considered a multi-storey building......Hydraulic unbalance is a common problem in Chinese district heating (DH) systems. Hydraulic unbalance has resulted in poor flow distribution among heating branches and overheating of apartments. Studies show that nearly 30% of the total heat supply is being wasted in Chinese DH systems due...... modelled in the IDA-ICE software, along with a self-developed mathematical hydraulic model to simulate its heat performance and hydraulic performance with various control scenarios. In contrast to the situation with no pressure or flow control, this solution achieves the required flow distribution...

Investigation the effect of outdoor air infiltration on the heat-shielding characteristics the outer walls of high-rise buildings

Science.gov (United States)

Vytchikov, Yu. S.; Kostuganov, A. B.; Saparev, M. E.; Belyakov, I. G.

2018-03-01

The presented article considers the influence of infiltrated outdoor air on the heat-shielding characteristics of the exterior walls of modern residential and public buildings. A review of the sources devoted to this problem confirmed its relevance at the present time, especially for high-rise buildings. The authors of the article analyzed the effect of longitudinal and transverse air infiltration on the heat-shielding characteristics of the outer wall of a 25-story building that was built in Samara. The results showed a significant reduction of the reduced resistance to the heat transfer of the outer wall when air is infiltrated through it. There are the results of full-scale examination of external walls to confirm the calculated data. Based on the results of the study carried out by the authors of the article, general recommendations on the internal finishing of the outer walls of high-rise buildings are given.

Methods of heat transformation for solar facilities in buildings; Verfahren der Waermetransformation fuer die solare Gebaeudetechnik

Energy Technology Data Exchange (ETDEWEB)

Henning, H.M. [Fraunhofer-Inst. fuer Solare Energiesysteme, Freiburg (Germany). Gruppe Aktive Thermische Systeme; Treffinger, P. [Deutsche Zentrum fuer Luft- und Raumfahrt (DLR), Lampoldshausen (Germany). Inst. fuer Technische Thermodynamik

1998-02-01

Processes in which a heat pump cycle is driven by thermal energy may be defined as heat transformation processes. The technical realization of this type of processes in general is based on sorption techniques. Depending on the temperature level of the utilized heat these technologies may be used for either cooling or heating of buildings. The paper presents state-of-the-art technologies and new developments. It comprises solar cooling of buildings, utilization of environmental energy sources (earth, air) by thermal driven heat pumps and seasonal storage of solar thermal energy by means of sorption processes. (orig.) [Deutsch] Unter Waermetransformationsverfahren werden im allgemeinen Verfahren verstanden, in denen ein Waermepumpenprozess mit thermischer Energie angetrieben wird. Die technische Realisierung dieser Verfahren erfolgt ueberwiegend mit Hilfe von Sorptionsvorgaengen. Abhaengig vom Temperaturniveau des Nutzwaermestroms koennen solche Verfahren im Gebaeudebereich fuer die Kuehlung oder Heizung eingesetzt werden. Im Beitrag werden der Stand der Technik sowie neue Entwicklungen vorgestellt. Im einzelnen umfasst der Beitrag die solare Kuehlung von Gebaeuden, die Nutzung von Umweltenergie (Erdreich, Luft) mittels thermisch angetriebener Waermepumpen sowie die saisonale Speicherung von Solarenergie ueber Sorptionsprozesse. (orig.)

Dual-purpose LWR supplying heat for desalination

International Nuclear Information System (INIS)

Waplington, G.; Fitcher, H.

1977-01-01

A number of desalination processes are at present in various stages of development but distillation is the only serious choice for a large-scale project. The distillation process temperature requirement is low compared with the temperature of steam normally delivered to the turbine in a power generation plant. This gives the possibility for combining the functions of electricity generation with water distillation. The brine heater of the multi-stage flash distillation plant can be supplied with steam after partial expansion through a turbine. Such an arrangement allows the use of a standard nuclear steam supply system and makes fuller use of the energy output than would either single purpose role. The LWR represents a safe, reliable and economic system, and is easily able to provide heat of a quality adequate for the desalination process. (M.S.)

Achievements and suggestions of heat metering and energy efficiency retrofit for existing residential buildings in northern heating regions of China

International Nuclear Information System (INIS)

Yan Ding; Zhe Tian; Yong Wu; Neng Zhu

2011-01-01

In order to promote energy efficiency and emission reduction, the importance of improving building energy efficiency received sufficient attention from Chinese Government. The heat metering and energy efficiency retrofit for existing residential buildings of 0.15 billion m 2 in northern heating regions of China was initiated in 2007 and completed successfully at the end of 2010. This article introduced the background and outline of the retrofit project during the period of 11th five-year plan. Numerous achievements that received by retrofit such as environmental protection effect, improvement of indoor environment, improvement of heating system, investment guidance effect, promotion of relevant industries and increasing chances of employment were concluded. Valuable experience that acquired from the retrofit project during the period of 11th five-year plan was also summarized in this article. By analyzing the main problems emerged in the past, pertinent suggestions were put forward to promote a larger scale and more efficient retrofit project in the period of 12th five-year plan. - Highlights: →Successful implementation of a retrofit project in China is introduced. → Significance of the project contributing to emission reduction is analyzed. →Achievements are summarized and future suggestions are put forward.

Effect of heat build-up on carbon emissions in chimato compost piles

African Journals Online (AJOL)

A. Mlangeni

atmospheric carbon compounds such as dioxide (CO2) and methane (CH4) into soil organic carbon compounds. (Biala, 2011; Gill et al., 2012; Biddlestone and Gray,. 1987). Maturity and stability of compost is partly dependent on type of feedstock that influence compost pile moisture content, aeration and heat build up. Well.

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.

The influence of soil moisture in the unsaturated zone on the heat loss from buildings via the ground

NARCIS (Netherlands)

Janssen, H.; Carmeliet, J.; Hens, H.

2002-01-01

In calculations of building heat loss via the ground, the coupling with soil moisture transfer is generally ignored, an important hypothesis which will be falsified in this paper. Results from coupled simulations - coupled soil heat and moisture transfer equations and complete surface heat and

Simulation of hybrid ground-coupled heat pump with domestic hot water heating systems using HVACSIM+

Energy Technology Data Exchange (ETDEWEB)

Cui, Ping; Yang, Hongxing [Department of Building Services Engineering, The Hong Kong Polytechnic University, Hong Kong (China); Spitler, Jeffrey D. [School of Mechanical Engineering, Oklahoma State University (United States); Fang, Zhaohong [Ground Source Heat Pump Research Center, Shandong University of Architecture and Engineering, Jinan (China)

2008-07-01

A hybrid ground-coupled heat pump (HGCHP) with domestic hot water (DHW) supply system has been proposed in this paper for space cooling/heating and DHW supply for residential buildings in hot-climate areas. A simulation model for this hybrid system is established within the HVACSIM+ environment. A sample system, applied for a small residential apartment located in Hong Kong, is hourly simulated in a typical meteorological year. The conventional GCHP system and an electric heater for DHW supply are also modeled and simulated on an hourly basis within the HVACSIM+ for comparison purpose. The results obtained from this case study show that the HGCHP system can effectively alleviate the imbalanced loads of the ground heat exchanger (GHE) and can offer almost 95% DHW demand. The energy saving for DHW heating is about 70% compared with an electric heater. This proposed scheme, i.e. the HGCHP with DHW supply, is suitable to residential buildings in hot-climate areas, such as in Hong Kong. (author)

Experimental and modelling analysis of an office building HVAC system based in a ground-coupled heat pump and radiant floor

International Nuclear Information System (INIS)

Villarino, José Ignacio; Villarino, Alberto; Fernández, Francisco Ángel

2017-01-01

Highlights: • A case study of a geothermal heat pump in an office building. • A numerical model in EnergyPlus is validated by experimental results. • An energy, economic and environmental analysis is presented. • A comparison with other technologies demonstrates the potential of the system. - Abstract: This paper shows the evaluation of the performance of a ground-coupled heat pump system monitored building providing heating, ventilating and air conditioning to an office building located in Madrid, in Spain. The system consists of one borehole exchanger, heat pump unit, radiant floor system, mechanical ventilation and data control system. A simulation model was performed with EnergyPlus software and validated. The analyzed period corresponds to the most unfavorable weather conditions in heating and cooling mode. The coefficient of performance obtained in heating and cooling mode was 3.86/5.29, considering all the energy consumption elements of the building and the thermal demand corresponding to an office operation. The CO_2 emissions obtained with a value of 34.68 kg corresponding to the period analyzed represents a low CO_2 emission system. The monitored temperatures reached set point values of 22 °C/25 °C, considered as acceptable comfort temperatures. The values obtained in the validated simulation model presented a deviation of 2% respected experimental results in heating and cooling mode. A comparative of COP_s_y_s and CO_2 emissions with other technologies is performed in order to analyze GCHP compared to other available technologies. The GCHP system is presented as a technology that can fully supply the HVAC conditions for a building and environmentally friendly.

Refurbishment of industrial buildings

International Nuclear Information System (INIS)

Gustafsson, Stig-Inge

2006-01-01

When a building is subject for refurbishment, there is a golden opportunity to change its behavior as an energy system. This paper shows the importance of careful investigations of the processes, the climate shield and the heating systems already present in the building before measures are implemented in reality. A case study is presented dealing with a carpentry factory. The building is poorly insulated according to standards today, and initially it was assumed that a better thermal shield would be of vital importance in order to reach optimal conditions. Instead, it is shown that the main problem is the ordinary heating system. This uses steam from a wood chips boiler and the wood chips come from the manufacturing processes. These wood chips are, therefore, a very cheap fuel. The boiler had, during decades of use, slowly degraded into a poor state. Hence, aero-tempers using expensive electricity have been installed to remedy the situation. These use not only expensive kWh but also very expensive kW due to the electricity tariff. It is shown that electricity for heating purposes must be abandoned and further, that this could be achieved at a surprisingly small cost. By stopping a large waste of steam, it was possible to find resources, in the form of unspent money, for further mending the existing heating system. Not only economy but also environmental hazards in the form of CO 2 emissions urges us to abandon electricity and instead use heat from cheap biomass fired boilers. Such equipment saves environment at the same time it saves money

UCC's Western Gateway Building: a Case Study for the Integration of Low Temperature Heating and High Temperature Cooling Systems

Directory of Open Access Journals (Sweden)

Michael F. Keohane

2012-04-01

Full Text Available This paper deals with the installation of a 1 MW groundwater heat pump for cool ing and heating, a server room heat recovery system and a novel VAV underfloor mechanical ventilation system, in a large third level university building in Cork, Ireland. After describing the building and the mechanical systems the paper presents energy usage and analysis of results for the first year in operation. Such an installation is of interest to engineers and facil ity managers in order to determine how all the systems complement each other, as well as the resultant energy saving potential compared to conventional systems. Large scale groundwater heat pumps with simultaneous heating and cooling capabilities can provide significant operational cost savings, as described in the paper.

Analysing the vulnerability of buildings to climate change: Summer heat and flooding

Directory of Open Access Journals (Sweden)

Johannes Nikolowski

2013-04-01

Full Text Available The REGKLAM project (Development and Testing of an Integrated Regional Climate Change Adaption Programme for the Model Region Dresden forms part of the KLIMZUG programme (Managing Climate Change in the Regions for the Future funded by the German Federal Ministry of Education and Research. It is concerned with the adaptation of important sectors of the Dresden region to climate change. One aim is to investigate and where necessary reduce the vulnerability of buildings and settlement structures to changing climatic conditions. This paper looks at flood damage as an example for the potential of climate change impacts on buildings. In ex-post analyses and projections, the article presents the results of regional climatological studies. Interfaces between meteorology and civil engineering are discussed. On the basis of a typology of building stock in the region, the vulnerability of given building types to given impacts was analysed in the form of impact models. The examples of environmental causes chosen were summer heat and flooding. The paper concludes with a discussion of how buildings can be adapted to cope with the impacts described.

Analysing the vulnerability of buildings to climate change. Summer heat and flooding

Energy Technology Data Exchange (ETDEWEB)

Nikolowski, Johannes; Zimm, Jakob; Naumann, Thomas [Leibniz Institute of Ecological Urban and Regional Development, Dresden (Germany); Goldberg, Valeri [Technische Univ. Dresden (Germany). Chair of Meteorology

2013-04-15

The REGKLAM project (Development and Testing of an Integrated Regional Climate Change Adaption Programme for the Model Region Dresden) forms part of the KLIMZUG programme (Managing Climate Change in the Regions for the Future) funded by the German Federal Ministry of Education and Research. It is concerned with the adaptation of important sectors of the Dresden region to climate change. One aim is to investigate and where necessary reduce the vulnerability of buildings and settlement structures to changing climatic conditions. This paper looks at flood damage as an example for the potential of climate change impacts on buildings. In ex-post analyses and projections, the article presents the results of regional climatological studies. Interfaces between meteorology and civil engineering are discussed. On the basis of a typology of building stock in the region, the vulnerability of given building types to given impacts was analysed in the form of impact models. The examples of environmental causes chosen were summer heat and flooding. The paper concludes with a discussion of how buildings can be adapted to cope with the impacts described. (orig.)

Exergetic analysis of the heat pump installed in the Limmat school building in Zurich; Exergieanalyse der Waermepumpe im Schulhaus Limmat - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Friedl, M.

2009-10-15

In large buildings, heat pumps todays are only used in a small number of cases. In those rare cases, they are operated with synthetic working fluids and are mainly used for low temperature heating. Since January 2006, a heat pump with Propane as working fluid has been operating in a school building in Zuerich (Schulhaus Limmat), which provides space heating and hot water for the old building erected in 1909. As a heat source, a main channel of sewage is used, an ideal heat source, which is only rarely used nowadays. Hence, the installation has a pioneering role in many aspects and has been analysed in detail during the current project. During this project, the Propane heat pump in the Schulhaus Limmat as well as the hydraulic system have been analysed in respect to its exergetic losses. The heat pump has a seasonal performance factor of 2.7. The investigation has shown that the heat pump does not operate in an optimal way and that the hydraulic has room for improvement with respect to exergetic losses. In implementing the measures suggested in this report, the seasonal performance factor can be increased to about 4.4. (author)

Simulation of the thermal performance of a hybrid solar-assisted ground-source heat pump system in a school building

Science.gov (United States)

Androulakis, N. D.; Armen, K. G.; Bozis, D. A.; Papakostas, K. T.

2018-04-01

A hybrid solar-assisted ground-source heat pump (SAGSHP) system was designed, in the frame of an energy upgrade study, to serve as a heating system in a school building in Greece. The main scope of this study was to examine techniques to reduce the capacity of the heating equipment and to keep the primary energy consumption low. Simulations of the thermal performance of both the building and of five different heating system configurations were performed by using the TRNSYS software. The results are presented in this work and show that the hybrid SAGSHP system displays the lower primary energy consumption among the systems examined. A conventional ground-source heat pump system has the same primary energy consumption, while the heat pump's capacity is double and the ground heat exchanger 2.5 times longer. This work also highlights the contribution of simulation tools to the design of complex heating systems with renewable energy sources.

The utilization of the storage of thermal energy in buildings. Underground heat storages - thermic simulation and profitability; Termisen energian varastoinnin hyvaeksikaeyttoemahdollisuudet rakennusten laemmityksessae ja jaeaehdytyksessae. Maanalaiset varastot - laempoetekninen simulointi ja taloudellinen kannattavuus

Energy Technology Data Exchange (ETDEWEB)

Suokas, M.; Heinonen, J.; Karola, A.; Laine, T.; Siren, K.

1998-12-31

Interest in different sources of free energy has significantly increased due to the possibility to decrease the consumption of fossil fuels and nuclear power. This can be reached, for example, with waste heat recovery and by utilising natural heat and cool energy sources. The main problem is that the supply and use of energy do not encounter and this causes a need for thermal energy storage. The earlier heat storage systems have utilised compressor heat pumps because the temperature levels of heat storages are not high enough for the ordinary heating and cooling systems. The disadvantage is the complexity of these systems which leads to increasing building costs. Therefore, this study deals with systems of low temperature levels used mainly for cooling purposes. The aim was to find out their usability, savings and profitability. The function and energy consumption of systems were simulated with models of buildings, soil heat storage and climate. The soil model simulates heat dynamic behaviour of the masses of soil. With the climate model it was possible to simulate transient heat losses of the storage and building. It was also possible to simulate various climatic conditions by changing input data of the climate model. In the simulated systems the emphasis is on the production of cooling energy by utilising the low temperature of the ground. The systems consist of heat storage and building. The cooling energy will be charged in winter to the storage when the heat energy charged in summer will be transferred to the supply air of ventilating unit. After the energy simulations the investment and usage costs of this kind of systems were compared with costs of ordinary compressor cooling systems. The buildings studied were an imaginary LVIS 2000 office building and the Messukeskus in Helsinki which is a large hall built for exhibitions. The types of soil were wet clay and granite. The LVIS 2000 office building needs a rock heat storage with capacity of 8 000-30 000 m

Building America Case Study: Multifamily Central Heat Pump Water Heaters, Davis, California

Energy Technology Data Exchange (ETDEWEB)

M. Hoeschele, E. Weitzel

2017-03-01

Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16-month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

Building America Case Study: Multifamily Central Heat Pump Water Heaters, Davis, California

Energy Technology Data Exchange (ETDEWEB)

2017-03-08

Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16-month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

Performance analysis of phase-change material storage unit for both heating and cooling of buildings

Science.gov (United States)

Waqas, Adeel; Ali, Majid; Ud Din, Zia

2017-04-01

Utilisation of solar energy and the night ambient (cool) temperatures are the passive ways of heating and cooling of buildings. Intermittent and time-dependent nature of these sources makes thermal energy storage vital for efficient and continuous operation of these heating and cooling techniques. Latent heat thermal energy storage by phase-change materials (PCMs) is preferred over other storage techniques due to its high-energy storage density and isothermal storage process. The current study was aimed to evaluate the performance of the air-based PCM storage unit utilising solar energy and cool ambient night temperatures for comfort heating and cooling of a building in dry-cold and dry-hot climates. The performance of the studied PCM storage unit was maximised when the melting point of the PCM was ∼29°C in summer and 21°C during winter season. The appropriate melting point was ∼27.5°C for all-the-year-round performance. At lower melting points than 27.5°C, declination in the cooling capacity of the storage unit was more profound as compared to the improvement in the heating capacity. Also, it was concluded that the melting point of the PCM that provided maximum cooling during summer season could be used for winter heating also but not vice versa.

Cooling performance of a vertical ground-coupled heat pump system installed in a school building

Energy Technology Data Exchange (ETDEWEB)

Hwang, Yujin; Lee, Jae-Keun; Jeong, Young-Man; Koo, Kyung-Min [Department of Mechanical Engineering, Pusan National University, San 30, Jangjeon-Dong, Kumjung-Ku, Busan 609-735 (Korea); Lee, Dong-Hyuk; Kim, In-Kyu; Jin, Sim-Won [LG Electronics, 391-2 Gaeumjeong-dong, Changwon City, Gyeongnam (Korea); Kim, Soo H. [Department of Nanosystems and Nanoprocess Engineering, Pusan National University, San 30, Jangjeon-Dong, Kumjung-Ku, Busan 609-735 (Korea)

2009-03-15

This paper presents the cooling performance of a water-to-refrigerant type ground heat source heat pump system (GSHP) installed in a school building in Korea. The evaluation of the cooling performance has been conducted under the actual operation of GSHP system in the summer of year 2007. Ten heat pump units with the capacity of 10 HP each were installed in the building. Also, a closed vertical typed-ground heat exchanger with 24 boreholes of 175 m in depth was constructed for the GSHP system. To analyze the cooling performance of the GSHP system, we monitored various operating conditions, including the outdoor temperature, the ground temperature, and the water temperature of inlet and outlet of the ground heat exchanger. Simultaneously, the cooling capacity and the input power were evaluated to determine the cooling performance of the GSHP system. The average cooling coefficient of performance (COP) and overall COP of the GSHP system were found to be {proportional_to}8.3 and {proportional_to}5.9 at 65% partial load condition, respectively. While the air source heat pump (ASHP) system, which has the same capacity with the GSHP system, was found to have the average COP of {proportional_to}3.9 and overall COP of {proportional_to}3.4, implying that the GSHP system is more efficient than the ASHP system due to its lower temperature of condenser. (author)

Urban weather data and building models for the inclusion of the urban heat island effect in building performance simulation

Directory of Open Access Journals (Sweden)

M. Palme

2017-10-01

Full Text Available This data article presents files supporting calculation for urban heat island (UHI inclusion in building performance simulation (BPS. Methodology is used in the research article “From urban climate to energy consumption. Enhancing building performance simulation by including the urban heat island effect” (Palme et al., 2017 [1]. In this research, a Geographical Information System (GIS study is done in order to statistically represent the most important urban scenarios of four South-American cities (Guayaquil, Lima, Antofagasta and Valparaíso. Then, a Principal Component Analysis (PCA is done to obtain reference Urban Tissues Categories (UTC to be used in urban weather simulation. The urban weather files are generated by using the Urban Weather Generator (UWG software (version 4.1 beta. Finally, BPS is run out with the Transient System Simulation (TRNSYS software (version 17. In this data paper, four sets of data are presented: 1 PCA data (excel to explain how to group different urban samples in representative UTC; 2 UWG data (text to reproduce the Urban Weather Generation for the UTC used in the four cities (4 UTC in Lima, Guayaquil, Antofagasta and 5 UTC in Valparaíso; 3 weather data (text with the resulting rural and urban weather; 4 BPS models (text data containing the TRNSYS models (four building models.

The effects of climate change on heating energy consumption of office buildings in different climate zones in China

Science.gov (United States)

Meng, Fanchao; Li, Mingcai; Cao, Jingfu; Li, Ji; Xiong, Mingming; Feng, Xiaomei; Ren, Guoyu

2017-06-01

Climate plays an important role in heating energy consumption owing to the direct relationship between space heating and changes in meteorological conditions. To quantify the impact, the Transient System Simulation Program software was used to simulate the heating loads of office buildings in Harbin, Tianjin, and Shanghai, representing three major climate zones (i.e., severe cold, cold, and hot summer and cold winter climate zones) in China during 1961-2010. Stepwise multiple linear regression was performed to determine the key climatic parameters influencing heating energy consumption. The results showed that dry bulb temperature (DBT) is the dominant climatic parameter affecting building heating loads in all three climate zones across China during the heating period at daily, monthly, and yearly scales (R 2 ≥ 0.86). With the continuous warming climate in winter over the past 50 years, heating loads decreased by 14.2, 7.2, and 7.1 W/m2 in Harbin, Tianjin, and Shanghai, respectively, indicating that the decreasing rate is more apparent in severe cold climate zone. When the DBT increases by 1 °C, the heating loads decrease by 253.1 W/m2 in Harbin, 177.2 W/m2 in Tianjin, and 126.4 W/m2 in Shanghai. These results suggest that the heating energy consumption can be well predicted by the regression models at different temporal scales in different climate conditions owing to the high determination coefficients. In addition, a greater decrease in heating energy consumption in northern severe cold and cold climate zones may efficiently promote the energy saving in these areas with high energy consumption for heating. Particularly, the likely future increase in temperatures should be considered in improving building energy efficiency.

Analysis of heat source selection for residential buildings in rural areas

Directory of Open Access Journals (Sweden)

Szul Tomasz

2018-01-01

Full Text Available The research aiming to check whether the output of currently installed boilers matches the use requirements together with estimation of their energy efficiency was carried out on a group of 84 single-family residential buildings located in rural areas. Heating and hot water energy needs were calculated for each building in order to determine the use requirements. This enabled verification whether the currently installed boilers match the actual use requirements in the buildings. Based on the calculations it was determined that the designed average boiler output in the group of buildings subject to analysis is 15.7 kW, whereas the mean rated output capacity of boilers installed therein is 25.4 kW. On average, the output capacity of the installed boilers exceeds the use requirements for the buildings by 60%. To calculate the energy efficiency of boilers, the mean annual boiler output capacity use coefficient was determined. For boilers selected on the basis of standard calculations, the mean coefficient is 0.47. For boilers currently in use it is 0.31, less than the above figure. The above calculations show that if boilers were correctly selected in compliance to the building needs, then the average estimated seasonal efficiency of 65% would be feasible. However, in the current state the achievable efficiency is approx. 55%.

Demand side management for smart district heating

DEFF Research Database (Denmark)

Big, Oovidiu; Li, Hongwei; Svendsen, Svend

2016-01-01

between 25% and 35%. By making the light renovation, the heating system needs a minimum supply water temperature of 58ºC in order to cover the thermal comfort. Through extensive renovation, the supply water temperature could be reduced to 50ºC which makes it possible to transform the District Heating...... Temperature into Low Temperature. The building time constant for the extensive renovation is 86 hours which is double than a light building renovation and 53 hours higher than a non-renovated building. In the end of the paper is developed a formula which has the purpose to validate the results of virtual...... simulations. The relative percentage difference between the theoretical calculation and the virtual simulation results are between 2.5% and 17.5%....

Central unresolved issues in thermal energy storage for building heating and cooling

Energy Technology Data Exchange (ETDEWEB)

Swet, C.J.; Baylin, F.

1980-07-01

This document explores the frontier of the rapidly expanding field of thermal energy storage, investigates unresolved issues, outlines research aimed at finding solutions, and suggests avenues meriting future research. Issues related to applications include value-based ranking of storage concepts, temperature constraints, consistency of assumptions, nomenclature and taxonomy, and screening criteria for materials. Issues related to technologies include assessing seasonal storage concepts, diurnal coolness storage, selection of hot-side storage concepts for cooling-only systems, phase-change storage in building materials, freeze protection for solar water heating systems, and justification of phase-change storage for active solar space heating.

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings: A case study of the Copenhagen district heating area in Denmark

International Nuclear Information System (INIS)

Harrestrup, M.; Svendsen, S.

2014-01-01

The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized heating plants that are too expensive to build in comparison with the potential energy savings in buildings. Long-term strategies for the existing building stock must ensure that costs are minimized and that investments in energy savings and new heating capacity are optimized and carried out at the right time. - Highlights: • We investigate how much heating consumption needs to be reduced in a district heating area. • We examine fossil-fuel-free supply vs. energy conservations in the building stock. • It is slightly cost-beneficial to invest in energy renovation from today for a societal point of view. • It is economically beneficial for district heating companies to invest in energy renovations from today. • The cost per delivered heat unit is lower when energy renovations are carried out from today

Low-energy district heating in energy-efficient building areas

DEFF Research Database (Denmark)

Dalla Rosa, Alessandro; Christensen, Jørgen Erik

2011-01-01

of a low-energy network for low-energy houses in Denmark. We took into account the effect of human behaviour on energy demand, the effect of the number of buildings connected to the network, a socio-economic comparison with ground source heat pumps, and opportunities for the optimization of the network...... to 0.20 MWh/(m year), and that the levelized cost of energy in low-energy DH supply is competitive with a scenario based on ground source heat pumps. The investment costs represent up to three quarters of the overall expenditure, over a time horizon of 30 years; so, the implementation of an energy...... system that fully relies on renewable energy needs substantial capital investment, but in the long term this is sustainable from the environmental and socio-economic points of view. Having demonstrated the value of the low-energy DH concept, we evaluated various possible designs with the aim of finding...

Modernization of heating systems. System solutions by renewabel heat in residnetial buildings. Consultant package; Heizungsmodernisierung. Systemloesungen mit erneuerbarer Waerme in Wohngebaeuden. Beratungspaket

Energy Technology Data Exchange (ETDEWEB)

Hartmann, F.

2008-07-01

Energy conservation measures in the area of buildings can considerably contribute to the planned reduction of CO{sub 2} emissions particularly if they are not only carried out in the field of new buildings but also in existing buildings. In this booklet technical possibilities and bases of constructional thermal insulation in modern construction engineering are described in detail. In this connection the following subjects are gone into: Low-energy houses, bases of heat and humidity technology, correct heating and ventilating, thermal insulation of heating systems and water heaters, renewable energy sources, legal obligations like energy passport, support possibilities, energy diagnosis and counselling. (GL) [German] Das Beratungspaket Heizungsmodernisierung wird Sie bei der Beratung und Kundeninformation rund um die Modernisierung von Heizungsanlagen unterstuetzen. Ansprechende Grafiken erleichtern die Orientierung in den technischen Details und geben Einblick in die Komplexitaet der Heizungsmodernisierung mit Hilfe regenerativer Energietechnik. Die Komponenten eines modernen, zeitgemaessen Heizsystems werden ebenso behandelt wie Investitionskosten, Betriebskosten und staatliche Foerderung. Von allgemeinen Informationen zur Waermeerzeugung fuer Heizung und Warmwasser bis hin zu wirtschaftlichen Alternativen durch Sonnenwaerme, Waermepumpen oder Heiztechnik mit Holz finden Sie alles, was der Kunde ueber moderne Heizsysteme fuer den Bestand wissen moechte. Auf der beiligenden CD-ROM finden Sie anschauliche Praesentationsgrafiken sowie Checklisten, die Sie zur Vorbereitung und im Kundengespraech nutzen oder Ihrem Kunden als Informationsmaterial ueberreichen koennen. (orig./GL)

Optimal Energy Management of Combined Cooling, Heat and Power in Different Demand Type Buildings Considering Seasonal Demand Variations

Directory of Open Access Journals (Sweden)

Akhtar Hussain

2017-06-01

Full Text Available In this paper, an optimal energy management strategy for a cooperative multi-microgrid system with combined cooling, heat and power (CCHP is proposed and has been verified for a test case of building microgrids (BMGs. Three different demand types of buildings are considered and the BMGs are assumed to be equipped with their own combined heat and power (CHP generators. In addition, the BMGs are also connected to an external energy network (EEN, which contains a large CHP, an adsorption chiller (ADC, a thermal storage tank, and an electric heat pump (EHP. By trading the excess electricity and heat energy with the utility grid and EEN, each BMG can fulfill its energy demands. Seasonal energy demand variations have been evaluated by selecting a representative day for the two extreme seasons (summer and winter of the year, among the real profiles of year-round data on electricity, heating, and cooling usage of all the three selected buildings. Especially, the thermal energy management aspect is emphasized where, bi-lateral heat trading between the energy supplier and the consumers, so-called energy prosumer concept, has been realized. An optimization model based on mixed integer linear programming has been developed for minimizing the daily operation cost of the EEN while fulfilling the energy demands of the BMGs. Simulation results have demonstrated the effectiveness of the proposed strategy.

Monitoring results and analysis of thermal comfort conditions in experimental buildings for different heating systems and ventilation regimes during heating and cooling seasons

Science.gov (United States)

Gendelis, S.; Jakovičs, A.; Ratnieks, J.; Bandeniece, L.

2017-10-01

This paper focuses on the long-term monitoring of thermal comfort and discomfort parameters in five small test buildings equipped with different heating and cooling systems. Calculations of predicted percentage of dissatisfied people (PPD) index and discomfort factors are provided for the room in winter season running three different heating systems - electric heater, air-air heat pump and air-water heat pump, as well as for the summer cooling with split type air conditioning systems. It is shown that the type of heating/cooling system and its working regime has an important impact on thermal comfort conditions in observed room. Recommendations for the optimal operating regimes and choice of the heating system from the thermal comfort point of view are summarized.

The influence of soil moisture transfer on building heat loss via the ground

NARCIS (Netherlands)

Janssen, H.M.; Carmeliet, J.; Hens, H.

2004-01-01

In this paper, the influence of soil moisture transfer on building heat loss via the ground is investigated by comparing fully coupled simulations with linear thermal simulations. The observed influences of coupling are (1) the larger amplitude of surface temperature, (2) the variation of thermal

Performance of a Solar Heating System with Photovoltaic Thermal Hybrid Collectors and Heat Pump

DEFF Research Database (Denmark)

Dannemand, Mark; Furbo, Simon; Perers, Bengt

2017-01-01

. When the solar collectors are unable to supply the heat demand an auxiliary heat source is used. Heat pumps can generate this heat. Liquid/water heat pumps have better performance than air/water heat pumps in cold climates but requires installation of a tubing system for the cold side of the heat pump....... The tubes are typically placed in the ground, requires a significant land area and increase the installation cost. A new system design of a solar heating system with two storage tanks and a liquid/water heat pump is presented. The system consists of PVT collectors that generate both heat and electricity......The energy consumption in buildings accounts for a large part of the World’s CO2 emissions. Much energy is used for appliances, domestic hot water preparation and space heating. In solar heating systems, heat is captured by solar collectors when the sun is shining and used for heating purposes...

Modelling the heat dynamics of a monitored Test Reference Environment for Building Integrated Photovoltaic systems using stochastic differential equations

DEFF Research Database (Denmark)

Lodi, C.; Bacher, Peder; Cipriano, J.

2012-01-01

reduce the ventilation thermal losses of the building by pre-heating the fresh air. Furthermore, by decreasing PV module temperature, the ventilation air heat extraction can simultaneously increase electrical and thermal energy production of the building. A correct prediction of the PV module temperature...... and heat transfer coefficients is fundamental in order to improve the thermo-electrical production.The considered grey-box models are composed of a set of continuous time stochastic differential equations, holding the physical description of the system, combined with a set of discrete time measurement......This paper deals with grey-box modelling of the energy transfer of a double skin Building Integrated Photovoltaic (BIPV) system. Grey-box models are based on a combination of prior physical knowledge and statistics, which enable identification of the unknown parameters in the system and accurate...

Study of the Dependence Effectiveness of Low-potential Heat of the Ground and Atmospheric Air for Heating Buildings from Climatic parameters

Directory of Open Access Journals (Sweden)

Vasilyev Gregory P.

2016-01-01

Full Text Available The article represents the results of researches for division into districts of the territory of Russia and Europe by efficiency of using for the heat supply of buildings of low-potential thermal energy of ground and free air and their combination. While modeling of the heat regime of geothermal HPS in climatic conditions of different regions of the territory of Russia, the influence has been taken into account of the long-term extraction of geothermal heat energy on the ground heat regime as well as the influence of phase transitions of pore moisture in ground on the efficiency of operation of geothermal heat-pump heat-supply systems. While realization of the division into districts, the sinking of temperatures of ground massive was been taken into account which has been called by long-term extraction of the heat energy from the ground, and as calculation parameters of the heat energy from the ground, and as calculation parameters of ground massive temperatures, the ground temperatures were used which are waited for the 5-th year of operation of geothermal HPS.

Impact of Building Design Parameters on Thermal Energy Flexibility in a Low-Energy Building

OpenAIRE

Sarran, Lucile; Foteinaki, Kyriaki; Gianniou, Panagiota; Rode, Carsten

2017-01-01

This work focuses on demand-side management potential for the heating grid in residential buildings. The possibility to increase the flexibility provided to the heat network through specific building design is investigated. The role of different parts of the building structure on thermal flexibility is assessed through a parameter variation on a building model. Different building designs are subjected to heat cut-offs, and flexibility is evaluated with respect to comfort preservation and heat...

Effect of facade components on energy efficiency in office buildings

International Nuclear Information System (INIS)

Ihara, Takeshi; Gustavsen, Arild; Jelle, Bjørn Petter

2015-01-01

Highlights: • Investigation of facade properties for energy efficiency of Tokyo office buildings. • Higher reflectance for opaque parts may slightly reduce energy demand. • Lower window U-value and solar heat gain coefficient are potential solutions. • Decreased heating due to insulation did not always compensate increased cooling. • Fundamental data for adjustment of facade properties of buildings are provided. - Abstract: Properties of facade materials should be considered to determine which of them strongly affect building energy performance, regardless of the building shapes, scales, ideal locations, and building types, and thus may be able to promote energy efficiency in buildings. In this study, the effects of four fundamental facade properties related to the energy efficiency of office buildings in Tokyo, Japan, were investigated with the purpose of reducing the heating and cooling energy demands. Some fundamental design factors such as volume and shape were also considered. It was found that the reduction in both the solar heat gain coefficient and window U-value and increase in the solar reflectance of the opaque parts are promising measures for reducing the energy demand. Conversely, the reduction in the U-value of the opaque parts decreased the heating energy demand, and this was accompanied by an increase in the cooling energy demand in some cases because the total energy demands were predominantly for cooling. The above-mentioned promising measures for reducing building energy demands are thus recommended for use, and an appropriate U-value should be applied to the opaque parts based on careful considerations. This study provides some fundamental ideas to adjust the facade properties of buildings.

Complex analysis of energy efficiency in operated high-rise residential building: Case study

Science.gov (United States)

Korniyenko, Sergey

2018-03-01

Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects). Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

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

Renewable-based low-temperature district heating for existing buildings in various stages of refurbishment

DEFF Research Database (Denmark)

Brand, Marek; Svendsen, Svend

2013-01-01

Denmark is aiming for a fossil-free heating sector for buildings by 2035. Judging by the national heating plan, this will be achieved mainly by a further spread of DH (district heating) based on the renewable heat sources. To make the most cost-effective use of these sources, the DH supply...... and, for 98% of the year, to below 60 °C. However for the temperatures below 60 °C a low-temperature DH substation is required for DHW (domestic hot water) heating. This research shows that renewable sources of heat can be integrated into the DH system without problems and contribute to the fossil...... temperature should be as low as possible. We used IDA–ICE software to simulate a typical Danish single-family house from the 1970s connected to DH at three different stages of envelope and space heating system refurbishment. We wanted to investigate how low the DH supply temperature can be without reducing...

Effect of heat build-up on carbon emissions in chimato compost piles ...

African Journals Online (AJOL)

A study was conducted to determine impacts of heat build-up of chimato compost piles TD0, TD20, TD40, TD50, TD60, TD80 and TD100, made by blending maize stalks with 0, 20, 40, 50, 60, 80 and 100% Tithonia diversifolia, respectively, on carbon losses and emissions during composting. Compost piles temperatures ...

Microgrids: An emerging paradigm for meeting building electricityand heat requirements efficiently and with appropriate energyquality

Energy Technology Data Exchange (ETDEWEB)

Marnay, Chris; Firestone, Ryan

2007-04-10

The first major paradigm shift in electricity generation,delivery, and control is emerging in the developed world, notably Europe,North America, and Japan. This shift will move electricity supply awayfrom the highly centralised universal service quality model with which weare familiar today towards a more dispersed system with heterogeneousqualities of service. One element of dispersed control is the clusteringof sources and sinks into semi-autonomous mu grids (microgrids).Research, development, demonstration, and deployment (RD3) of mu gridsare advancing rapidly on at least three continents, and significantdemonstrations are currently in progress. This paradigm shift will resultin more electricity generation close to end-uses, often involvingcombined heat and power application for building heating and cooling,increased local integration of renewables, and the possible provision ofheterogeneous qualities of electrical service to match the requirementsof various end-uses. In Europe, mu grid RD3 is entering its third majorround under the 7th European Commission Framework Programme; in the U.S.,one specific mu grid concept is undergoing rigorous laboratory testing,and in Japan, where the most activity exists, four major publiclysponsored and two privately sponsored demonstrations are in progress.This evolution poses new challenges to the way buildings are designed,built, and operated. Traditional building energy supply systems willbecome much more complex in at least three ways: 1. one cannot simplyassume gas arrives at the gas meter, electricity at its meter, and thetwo systems are virtually independent of one another; rather, energyconversion, heat recovery and use, and renewable energy harvesting mayall be taking place simultaneously within the building energy system; 2.the structure of energy flows in the building must accommodate multipleenergy processes in a manner that permits high overall efficiency; and 3.multiple qualities of electricity may be supplied to

Two-Pipe Chilled Beam System for Both Cooling and Heating of Office Buildings

DEFF Research Database (Denmark)

Afshari, Alireza; Gordnorouzi, Rouzbeh; Hultmark, Göran

2013-01-01

Simulations were performed to compare a conventional 4-pipe chilled beam system and a 2-pipe chilled beam system. The objective was to establish requirements, possibilities and limitations for a well-functioning 2-pipe chilled beam system for both cooling and heating of office buildings. The buil...

Variable Conductance Heat Pipe Cooling of Stirling Convertor and General Purpose Heat Source

Science.gov (United States)

Tarau, Calin; Schwendeman, Carl; Anderson, William G.; Cornell, Peggy A.; Schifer, Nicholas A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

Evaluation of Active Cooling Systems for Non-Residential Buildings

Directory of Open Access Journals (Sweden)

M.A. Othuman Mydin

2014-05-01

Full Text Available Cooling systems are an essential element in many facets of modern society including cars, computers and buildings. Cooling systems are usually divided into two types: passive and active. Passive cooling transfers heat without using any additional energy while active cooling is a type of heat transfer that uses powered devices such as fans or pumps. This paper will focus on one particular type of passive cooling: air-conditioning systems. An air-conditioning system is defined as controlled air movement, temperature, humidity and cleanliness of a building area. Air conditioning consists of cooling and heating. Therefore, the air-conditioning system should be able to add and remove heat from the area. An air-conditioning system is defined as a control or treatment of air in a confined space. The process that occurs is the air-conditioning system absorbs heat and dust while, at the same time, cleaning the air breathed into a closed space. The purpose of air-conditioning is to maintain a comfortable atmosphere for human life and to meet user requirements. In this paper, air-conditioning systems for non-residential buildings will be presented and discussed.

Building an eco-effective district heating management system in a city

Directory of Open Access Journals (Sweden)

Gitelman Leonid

2016-01-01

Full Text Available The goal of making the urban environment safer amid increasing human impact adds to the importance of district heating management. The article outlines the results of a study into the problem of improving the urban environment by implementing two innovative solutions. Technological innovations imply the introduction of modern sustainable tools of reducing emissions in district heating networks, one of them being the combination of district heating and combined heat and power plants (a case study of Turin. Organizational innovations are built upon the management of demand for thermal energy that makes it possible to reduce investment in new construction and to optimize the architecture of heat load schedules for the purpose of alleviating energy and environmental pressure on the city. The authors propose formats and areas of demand side management for thermal energy and methods of offering economic incentives to program participants.

Conservative modelling of the moisture and heat transfer in building components under atmospheric excitation

DEFF Research Database (Denmark)

Janssen, Hans; Blocken, Bert; Carmeliet, Jan

2007-01-01

While the transfer equations for moisture and heat in building components are currently undergoing standardisation, atmospheric boundary conditions, conservative modelling and numerical efficiency are not addressed. In a first part, this paper adds a comprehensive description of those boundary...

What land covers are effective in mitigating a heat island in urban building rooftop?

Science.gov (United States)

Lee, S.; Ryu, Y.

2014-12-01

Since the 20th century, due to the rapid urbanization many urban environment problems have got blossomed and above all heat island has been recognized as an important issue. There are several causes of urban heat island, but land cover change occupies the largest portion of them. Owing to urban expansion, vegetation is changed into asphalt pavements and concrete buildings, which reduces latent heat flux. To mitigate the problems, people enlarge vegetation covers such as planting street trees, making rooftop gardens and constructing parks or install white roofs that feature high albedo on a building. While the white roofs reflect about 70% of solar radiation and absorb less radiation, vegetation has low albedo but cools the air through transpiration and fixes carbon dioxide through photosynthesis. There are some studies concerning which one is more effective to mitigate heat island between the green roof and white roof. This study compares the green roof and white roof and additionally considers carbon fixation that has not been treated in other studies. Furthermore, this study ascertains an efficiency of solar-cell panel that is used for building roof recently. The panel produces electric power but has low albedo which could warm the air. The experiment is conducted at the rooftop in Seoul, Korea and compares green roof (grass), white roof (painted cover), black roof (solar panel) and normal painted roof. Surface temperature and albedo are observed for the four roof types and incoming shortwave, outgoing longwave and carbon flux are measured in green roof solely. In the case of solar panels, the electricity generation is calculated from the incoming radiation. We compute global warming potentials for the four roof types and test which roof type is most effective in reducing global warming potential.

Quantitative Analysis of the Principal-Agent Problem in Commercial Buildings in the U.S.: Focus on Central Space Heating and Cooling

Energy Technology Data Exchange (ETDEWEB)

Blum, Helcio; Sathaye, Jayant

2010-05-14

We investigate the existence of the principal-agent (PA) problem in non-government, non-mall commercial buildings in the U.S. in 2003. The analysis concentrates on space heating and cooling energy consumed by centrally installed equipment in order to verify whether a market failure caused by the PA problem might have prevented the installation of energy-efficient devices in non-owner-occupied buildings (efficiency problem) and/or the efficient operation of space-conditioning equipment in these buildings (usage problem). Commercial Buildings Energy Consumption Survey (CBECS) 2003 data for single-owner, single-tenant and multi-tenant occupied buildings were used for conducting this evaluation. These are the building subsets with the appropriate conditions for assessing both the efficiency and the usage problems. Together, these three building types represent 51.9percent of the total floor space of all buildings with space heating and 59.4percent of the total end-use energy consumption of such buildings; similarly, for space cooling, they represent 52.7percent of floor space and 51.6percent of energy consumption. Our statistical analysis shows that there is a usage PA problem. In space heating it applies only to buildings with a small floor area (<_50,000 sq. ft.). We estimate that in 2003 it accounts for additional site energy consumption of 12.3 (+ 10.5 ) TBtu (primary energy consumption of 14.6 [+- 12.4] TBtu), corresponding to 24.0percent (+- 20.5percent) of space heating and 10.2percent (+- 8.7percent) of total site energy consumed in those buildings. In space cooling, however, the analysis shows that the PA market failure affects the complete set of studied buildings. We estimate that it accounts for a higher site energy consumption of 8.3 (+-4.0) TBtu (primary energy consumption of 25.5 [+- 12.2]TBtu), which corresponds to 26.5percent (+- 12.7percent) of space cooling and 2.7percent (+- 1.3percent) of total site energy consumed in those buildings.

Characterization of commercial building appliances. Final report

Energy Technology Data Exchange (ETDEWEB)

Patel, R.F.; Teagan, P.W.; Dieckmann, J.T.

1993-08-01

This study focuses on ``other`` end-uses category. The purpose of this study was to determine the relative importance of energy end-use functions other than HVAC and lighting for commercial buildings, and to identify general avenues and approaches for energy use reduction. Specific energy consuming technologies addressed include non-HVAC and lighting technologies in commercial buildings with significant energy use to warrant detailed analyses. The end-uses include office equipment, refrigeration, water heating, cooking, vending machines, water coolers, laundry equipment and electronics other than office equipment. The building types include offices, retail, restaurants, schools, hospitals, hotels/motels, grocery stores, and warehouses.

Conflicting strategies towards sustainable heating at an urban junction of heat infrastructure and building standards

International Nuclear Information System (INIS)

Späth, Philipp; Rohracher, Harald

2015-01-01

Approaches to ‘sustainability transitions’ stress the possibility of aligning actors around a shared vision of the future, e.g. at the scale of a city. Empirical accounts reveal how difficult such coordination often is due to contradictory views involved. How can we better understand related processes of searching and negotiation? What does this mean for the organization of decision making processes regarding long-term infrastructural change? We analyze a conflict which erupted in Freiburg, Germany when two strategies of reducing environmental impacts of space heating were to be applied in the Vauban ‘model district’: A) Efficient co-generation of heat and power (CHP) combined with district heating systems (DHS), and B) Reducing heat demand by low-energy designs and ambitious energy standards (‘passive house standard’). In order to understand the politics of infrastructure development, we unravel 1) enabling factors and driving forces of the conflict, 2) normative content of opposing viewpoints, 3) resources tapped into for settling the disagreement, and 4) the institutional setup of such decision making about energy policy priorities in the municipality. We reflect on implications of such a perspective on how policies and how governance arrangements should ideally be shaped and take a brief outlook on further research needed. - Highlights: • Foregrounds likeliness of conflicts over strategies within sustainability transitions. • District heating systems can be incommensurate with low energy building standards. • Studies one such conflict in an urban context (Freiburg, Germany) in depth. • Processes of urban planning can reveal frictions within and between infrastructures. • Can such junctions as opportunities for re-negotiation of strategies be anticipated?

MODERN BUILDING STRUCTURES USED FOR MILITARY PURPOSES

Directory of Open Access Journals (Sweden)

Mariana Domnica STANCIU

2014-04-01

Full Text Available This paper investigates the technical aspects of the spherical spatial structures, focusing on the tensegrity building systems used for military purpose. The spherical spatial structures have been studied and used since antiquity. Pythagoras, Plato and Euclid were conducted extensive research on the concept of such type of structures. Regular pentagon has properties related to the value of the golden section, intuitively used by great architects and engineers since ancient times. In the Middle Ages, Leonardo Da Vinci created spatial objects using proportions based on the golden number, and later R. B. Fuller made the famous geodesic domes. The structures proposed by the authors are based on concepts related to the "golden section", on studies made on the regular pentagon, on the spatial volumes able to be inscribed in spheres and on the tensegrity systems. The proposed structures present some advantages related to the ease of mounting, to the volume covered, to the resistance to the environmental factors (snow, wind, earthquake, and so on. The paper presents the conclusions of the investigations on the components of the spatial structures and on the outcomes of their use.

Design evolution and verification of the general-purpose heat source

International Nuclear Information System (INIS)

Schock, A.

The General-Purpose Heat Source (GPHS) is a radioisotope heat source for use in space power systems. It employs a modular design, to make it adaptable to a wide range of energy conversion systems and power levels. Each 250 W module is completely autonomous, with its own passive safety provisions to prevent fuel release under all abort modes, including atmospheric reentry and earth impact. Prior development tests had demonstrated good impact survival as long as the iridium fuel capsules retained their ductility. This requires high impact temperatures, typically above 900 0 C and reasonably fine grain size, which in turn requires avoidance of excessive operating temperatures and reentry temperatures. These three requirements - on operating, reentry, and impact temperatures - are in mutual conflict, since thermal design changes to improve any one of these temperatures tend to worsen one or both of the others. This conflict creates a difficult design problem, which for a time threatened the success of the program. The present paper describes how this problem was overcome by successive design revisions, supplemented by thermal analyses and confirmatory vibration and impact tests; and how this may be achieved while raising the specific power of the GPHS to 83 W/lb, a 50% improvement over previously flown radioisotope heat sources

Energy performance requirements for new buildings in 11 countries from Central Europe. Exemplary comparison of three buildings

Energy Technology Data Exchange (ETDEWEB)

Loga, Tobias; Knissel, Jens; Diefenbach, Nikolaus

2008-12-05

The objective of the present comparison study is to show which energy efficiency require-ments have to be complied in different European countries when a new building is going to be constructed. For this purpose three Model Buildings were defined: a single-family house, a multi-family house and a school building. For each involved country (or region) the energy quality of the thermal envelope was determined which is necessary in order to just comply with the building code. Due to requirements on the overall energy performance the requested envelope quality usually depends also on the type of heat supply system or energy carrier. Therefore the systems were varied in a parameter study. The main result for each of the three Model Buildings is a comparison table which shows the heat transfer coefficient by transmission (a sort of mean U-value) for the different countries differenti-ated by supply system types. In a final step the primary energy demand according to the German regulation (EnEV 2007) was calculated for every envelope/system combination of the different countries. This allows a comparison of buildings with different supply systems. The study was performed by experts from 11 European member states: Germany, Austria, Czech Republic, Poland, Sweden, Denmark, UK, The Netherlands, Belgium, Luxembourg and France. (orig.)

On the Evaluation of Solar Greenhouse Efficiency in Building Simulation during the Heating Period

Directory of Open Access Journals (Sweden)

Francesco Asdrubali

2012-06-01

Full Text Available Among solar passive systems integrated in buildings, sunspaces or solar greenhouses represent a very interesting solution. A sunspace is a closed, southbound volume, constituted by transparent surfaces, adjacent to a building, which reduces winter energy demand thanks to the use of solar gains. The effect of a typical solar greenhouse on the energy balance of a building was evaluated during the heating period with two stationary procedures (Method 5000 and EN ISO 13790 and with a dynamic tool (TRNSYS. After the analysis of the greenhouse alone, the behavior of an entire house was simulated; a flat equipped with a sunspace, recently built thanks to public contributions provided by the Umbria Region in Italy to widespread bio-climatic architecture, was used as case-study. Simulations were carried out for the examined flat, both with a steady-state tool and with a dynamic one; the contribution of the sunspace was estimated thanks to the various methods previously mentioned. Finally, the simulated data were satisfactorily compared with the real energy consumptions (natural gas for heating of the flat; the sunspace allows a reduction of winter energy demand of the flat of about 20%.

Effects of building aspect ratio, diurnal heating scenario, and wind speed on reactive pollutant dispersion in urban street canyons.

Science.gov (United States)

Tong, Nelson Y O; Leung, Dennis Y C

2012-01-01

A photochemistry coupled computational fluid dynamics (CFD) based numerical model has been developed to model the reactive pollutant dispersion within urban street canyons, particularly integrating the interrelationship among diurnal heating scenario (solar radiation affections in nighttime, daytime, and sun-rise/set), wind speed, building aspect ratio (building-height-to-street-width), and dispersion of reactive gases, specifically nitric oxide (NO), nitrogen dioxide (NO2) and ozone (O3) such that a higher standard of air quality in metropolitan cities can be achieved. Validation has been done with both experimental and numerical results on flow and temperature fields in a street canyon with bottom heating, which justifies the accuracy of the current model. The model was applied to idealized street canyons of different aspect ratios from 0.5 to 8 with two different ambient wind speeds under different diurnal heating scenarios to estimate the influences of different aforementioned parameters on the chemical evolution of NO, NO2 and O3. Detailed analyses of vertical profiles of pollutant concentrations showed that different diurnal heating scenarios could substantially affect the reactive gases exchange between the street canyon and air aloft, followed by respective dispersion and reaction. Higher building aspect ratio and stronger ambient wind speed were revealed to be, in general, responsible for enhanced entrainment of O3 concentrations into the street canyons along windward walls under all diurnal heating scenarios. Comparatively, particular attention can be paid on the windward wall heating and nighttime uniform surface heating scenarios.

NRC new sustainable building

International Nuclear Information System (INIS)

Semczyszyn, D.

2004-01-01

'Full text:' The National Research Council Institute For Fuel Cell Innovation is relocating to a purpose-built 71,343 sq. Ft. (6598 sq. M) Research, Testing, Evaluation, and Industry Incubation Facility in the spring of 2006. The new facility will contain Hydrogen-ready laboratories, the existing relocated Hydrogen Safe Environmental Test Chamber, a hydrogen vehicle maintenance bay, a hydrogen vehicle refuelling station, and the following demonstration projects and features: 1. A Ground Source Heat Pump: This long-proven natural-source heating and cooling technology to provide climate control for the new IFCI's atrium and galleria. It is being designed by Keen Engineering of North Vancouver, BC. 2. 5 KW Solid Oxide Fuel Cell System: Fuelled by natural gas and in the future, from biomass, the fuel cell will also produce approximately 15 kW of waste heat, which will be captured and used to supply heat for the building. The Solid Oxide Fuel Cell will be supplied by Fuel Cell Technologies in Kingston, ON. 3. LEED Building certification: Attaining LEED 'green building' certification is considered an important complement to the plans for the new NRC-IFCI, because it will provide respected third-party verification of government's commitment to efficient building design and construction. Project architects Bunting Coady of Vancouver, BC believe the IFCI has strong potential to earn gold LEED certification. 4. Photovoltaic hydrogen source for back-up power fuel cell system: A photovoltaic array will capture energy from sunlight to power an electrolyzer that will produce and store hydrogen for a PEM fuel cell emergency backup power system. The electrolyzer will be provided by Hydrogenics of Mississauga, ON. Photovoltaics are being designed and installed by the British Columbia Institute of Technology. (author)

Investigation on Solar Heating System with Building-Integrated Heat Storage

DEFF Research Database (Denmark)

Heller, Alfred

1996-01-01

Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating and due to storage. The storage affects the heat demand passively due to higher temperatures. Hence heat loss is reduced and passive heating is optioned. In theory, by running the system flow backwards, active heating can...... solar collector area of the system, was achieved. Active heating from the sand storage was not observed. The pay-back time for the system can be estimated to be similar to solar heated domestic hot water systems in general. A number of minor improvements on the system could be pointed out....

Complex analysis of energy efficiency in operated high-rise residential building: Case study

Directory of Open Access Journals (Sweden)

Korniyenko Sergey

2018-01-01

Full Text Available Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects. Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

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.

The exploitation of biomass for building space heating in Greece: Energy, environmental and economic considerations

International Nuclear Information System (INIS)

Michopoulos, A.; Skoulou, V.; Voulgari, V.; Tsikaloudaki, A.; Kyriakis, N.A.

2014-01-01

Highlights: • The oil substitution with biomass residues for heating buildings is examined. • Primary energy consumption from biomass results increased by 3–4% as compared to diesel oil. • CO 2 and SO 2 emissions are significantly higher with biomass than with diesel oil. • The examined substitution is economically attractive for the final consumers. - Abstract: The exploitation of forest and agricultural biomass residues for energy production may offer significant advantages to the energy policy of the relevant country, but it strongly depends on a number of financial, technological and political factors. The work in hand focuses on the investigation of the energy, environmental and financial benefits, resulting from the exploitation of forest and agricultural biomass residues, fully substituting the conventional fuel (diesel oil) for building space heating in Greece. For this investigation, the energy needs of a representative building are determined using the EnergyPlus software, assuming that the building is located across the various climate zones of Greece. Based on the resulting thermal energy needs, the primary energy consumption and the corresponding emissions are determined, while an elementary fiscal analysis is also performed. The results show that significant financial benefits for the end-user are associated with the substitution examined, even though increased emissions and primary energy consumption have been derived

Utilization of the PCM latent heat for energy savings in buildings

Science.gov (United States)

Fořt, Jan; Trník, Anton; Pavlík, Zbyšek

2017-07-01

Increase of the energy consumption for buildings operation creates a great challenge for sustainable development issues. Thermal energy storage systems present promising way to achieve this goal. The latent heat storage systems with high density of thermal storage via utilization of phase change materials (PCMs) enable to improve thermal comfort of buildings and reduce daily temperature fluctuations of interior climate. The presented study is focused on the evaluation of the effect of PCM admixture on thermal performance of a cement-lime plaster. On the basis of the experimentally accessed properties of newly developed plasters, computational modeling is carried out in order to rate the acquired thermal improvement. The calculated results show that incorporation of 24 mass% of paraffinic wax based PCM decreased the energy demand of approx. 14.6%.

The ORC method. Effective modelling of thermal performance of multilayer building components

Energy Technology Data Exchange (ETDEWEB)

Akander, Jan

2000-02-01

The ORC Method (Optimised RC-networks) provides a means of modelling one- or multidimensional heat transfer in building components, in this context within building simulation environments. The methodology is shown, primarily applied to heat transfer in multilayer building components. For multilayer building components, the analytical thermal performance is known, given layer thickness and material properties. The aim of the ORC Method is to optimise the values of the thermal resistances and heat capacities of an RC-model such as to give model performance a good agreement with the analytical performance, for a wide range of frequencies. The optimisation procedure is made in the frequency domain, where the over-all deviation between model and analytical frequency response, in terms of admittance and dynamic transmittance, is minimised. It is shown that ORC's are effective in terms of accuracy and computational time in comparison to finite difference models when used in building simulations, in this case with IDA/ICE. An ORC configuration of five mass nodes has been found to model building components in Nordic countries well, within the application of thermal comfort and energy requirement simulations. Simple RC-networks, such as the surface heat capacity and the simple R-C-configuration are not appropriate for detailed building simulation. However, these can be used as basis for defining the effective heat capacity of a building component. An approximate method is suggested on how to determine the effective heat capacity without the use of complex numbers. This entity can be calculated on basis of layer thickness and material properties with the help of two time constants. The approximate method can give inaccuracies corresponding to 20%. In-situ measurements have been carried out in an experimental building with the purpose of establishing the effective heat capacity of external building components that are subjected to normal thermal conditions. The auxiliary

An office building of Paris city air-conditioned by an aquifer-source heat pump; Un immeuble parisien climatise par une thermofrigopompe sur nappe phreatique

Energy Technology Data Exchange (ETDEWEB)

Anon.

2003-09-01

A 7000 m{sup 2} office building of Paris (France) is equipped with an aquifer-source heat pump for the space heating and cooling. This choice allows to save 28400 euros of heating/cooling expenses each year with respect to other solutions. The equipment ensures also the production of hot and chilled water and the calories recovered from the refrigeration system are used to supply the space heating needs of the building. This paper describes the equipments (heat pump, heat exchangers, ventilation-convection systems), the centralized control system and the cost-benefit aspects. (J.S.)

Solar building

OpenAIRE

Zhang, Luxin

2014-01-01

In my thesis I describe the utilization of solar energy and solar energy with building integration. In introduction it is also mentioned how the solar building works, trying to make more people understand and accept the solar building. The thesis introduces different types of solar heat collectors. I compared the difference two operation modes of solar water heating system and created examples of solar water system selection. I also introduced other solar building applications. It is conv...

Building America Case Study: Impact of Slab-Foundation Heat Transfer on Space-Conditioning Energy Use in Florida, Cocoa, Florida

Energy Technology Data Exchange (ETDEWEB)

2016-12-01

Heat transfer to slab foundations has remained an area of building science with poor understanding over the last three decades of energy efficiency research. This is somewhat surprising since the area of floors in single family homes is generally equal to wall, or windows or attics which have been extensively evaluated. Research that has been done has focused in the impact of slab on grade foundations and insulation schemes on heat losses associated with heating in predominantly heating dominated climates. Slab on grade construction is very popular in cooling-dominated southern states where it accounts for 77 percent of new home floors according to U.S. Census data in 2014. There is a widespread conception that tile flooring, as opposed to carpet, makes for a cooler home interior in warm climates. Empirical research is needed as building energy simulations such as DOE-2 and EnergyPlus rely on simplified models to evaluate these influences. BA-PIRC performed experiments over an entire year from 2014-2015 in FSEC's Flexible Residential Test Facilities (FRTF) intended to assess for the first time 1) slab on grade influence in a cooling dominated climate, and 2) how the difference in a carpeted vs. uncarpeted building might influence heating and cooling. Two identical side by side residential buildings were evaluated, the East with pad and carpet and the west with a bare slab floor. A highly detailed grid of temperature measurements were taken on the slab surface at various locations as well as at depths of 1, 2.5, 5, 10 and 20 feet.

Energy analysis of an improved concept of integrated PV panels in an office building in central Greece

Energy Technology Data Exchange (ETDEWEB)

Zogou, Olympia; Stapountzis, Herricos [University of Thessaly, Mechanical Engineering Department, Volos (Greece)

2011-03-15

During the last decade, steel constructions with glazed facades became popular for commercial buildings in Greece. Moreover, expensive metal, natural stone, marble, ceramic, granite as well as special glass is employed for aesthetic and energy efficiency reasons. This creates opportunities for the introduction of Photovoltaic (PV) modules in double facades. PV modules on south-facing building walls are better placed at a distance from the wall to allow heat rejection and avoid overheating and efficiency loss. Exploiting the rejected heat of the PV modules is also a challenge. In this paper, we examine an improved concept of incorporating PV modules to the south facades of an office building, exploiting both the electricity produced and the heat rejected by the module, to increase building energy efficiency. The PV modules are integrated to the building wall by means of a double facade, which employs intervening ducts for ventilation purposes. The ducts are heating outdoor air, which is employed to cover the ventilation needs of the building, as well as a part of the heating loads. Simulations for typical winter and summer weather and solar insolation conditions are carried out to investigate the building's energy performance improvements. (author)

Energy analysis of an improved concept of integrated PV panels in an office building in central Greece

International Nuclear Information System (INIS)

Zogou, Olympia; Stapountzis, Herricos

2011-01-01

During the last decade, steel constructions with glazed facades became popular for commercial buildings in Greece. Moreover, expensive metal, natural stone, marble, ceramic, granite as well as special glass is employed for aesthetic and energy efficiency reasons. This creates opportunities for the introduction of Photovoltaic (PV) modules in double facades. PV modules on south-facing building walls are better placed at a distance from the wall to allow heat rejection and avoid overheating and efficiency loss. Exploiting the rejected heat of the PV modules is also a challenge. In this paper, we examine an improved concept of incorporating PV modules to the south facades of an office building, exploiting both the electricity produced and the heat rejected by the module, to increase building energy efficiency. The PV modules are integrated to the building wall by means of a double facade, which employs intervening ducts for ventilation purposes. The ducts are heating outdoor air, which is employed to cover the ventilation needs of the building, as well as a part of the heating loads. Simulations for typical winter and summer weather and solar insolation conditions are carried out to investigate the building's energy performance improvements.

Electricity use characteristics of purpose-built office buildings in subtropical climates

International Nuclear Information System (INIS)

Lam, Joseph C.; Chan, Ricky Y.C.; Tsang, C.L.; Li, Danny H.W.

2004-01-01

The electricity use characteristics of 20 air conditioned office buildings in the public sector in subtropical Hong Kong were investigated. Monthly electricity consumption data were gathered and analysed. The annual electricity use per unit gross floor area ranged from 163 to 389 kW h/m 2 , with a mean of 270 kW h/m 2 . Detailed energy audits and site surveys were conducted to obtain a breakdown of the energy use. The percentage consumption for the four major electricity end users, namely heating, ventilation and air conditioning, lighting, electrical equipment and lifts and escalators were 47.5%, 27.4%, 21.8% and 3.3%, respectively. Regression techniques were used to correlate the monthly electricity use with the design and climatic variables. This paper presents the work and discusses the energy use implications

Microgrids: An emerging paradigm for meeting building electricity and heat requirements efficiently and with appropriate energy quality

Energy Technology Data Exchange (ETDEWEB)

Marnay, Chris; Firestone, Ryan [Berkeley Lab MS 90R4000 (United States)

2007-07-01

The first major paradigm shift in electricity generation, delivery, and control is emerging in the developed world, notably Europe, North America, and Japan. This shift will move electricity supply away from the highly centralised universal service quality model with which we are familiar today towards a more dispersed system with heterogeneous qualities of service. One element of dispersed control is the clustering of sources and sinks into semi-autonomous {mu}grids (microgrids). Research, development, demonstration, and deployment (RD3) of {mu}grids are advancing rapidly on at least three continents, and significant demonstrations are currently in progress. This paradigm shift will result in more electricity generation close to end-uses, often involving combined heat and power application for building heating and cooling, increased local integration of renewables, and the possible provision of heterogeneous qualities of electrical service to match the requirements of various end-uses. In Europe, microgrid RD3 is entering its third major round under the 7th European Commission Framework Programme; in the U.S., one specific microgrid concept is undergoing rigorous laboratory testing, and in Japan, where the most activity exists, four major publicly sponsored and two privately sponsored demonstrations are in progress. This evolution poses new challenges to the way buildings are designed, built, and operated. Traditional building energy supply systems will become much more complex in at least three ways: 1. one cannot simply assume gas arrives at the gas meter, electricity at its meter, and the two systems are virtually independent of one another; rather, energy conversion, heat recovery and use, and renewable energy harvesting may all be taking place simultaneously within the building energy system; 2. the structure of energy flows in the building must accommodate multiple energy processes in a manner that permits high overall efficiency; and 3. multiple qualities

Method for reducing excess heat supply experienced in typical Chinese district heating systems by achieving hydraulic balance and improving indoor air temperature control at the building level

International Nuclear Information System (INIS)

Zhang, Lipeng; Gudmundsson, Oddgeir; Thorsen, Jan Eric; Li, Hongwei; Li, Xiaopeng; Svendsen, Svend

2016-01-01

A common problem with Chinese district heating systems is that they supply more heat than the actual heat demand. The reason for this excess heat supply is the general failure to use control devices to adjust the indoor temperature and flow in the building heating systems in accordance with the actual heat demand. This results in 15–30% of the total supplied heat being lost. This paper proposes an integrated approach that aims to reduce the excess heat loss by introducing pre-set thermostatic radiator valves combined with automatic balancing valves. Those devices establish hydraulic balance, and stabilize indoor temperatures. The feasibility and the energy consumption reduction of this approach were verified by means of simulation and a field test. By moving the system from centrally planned heat delivery to demand-driven heat delivery, excess heat loss can be significantly reduced. Results show that once the hydraulic balance is achieved and indoor temperatures are controlled with this integrated approach, 17% heat savings and 42.8% pump electricity savings can be achieved. The energy savings will also have a positive environmental effect with seasonal reductions of 11 kg CO_2, 0.1 kg SO_2, and 0.03 kg NO_x per heating square meter for a typical case in Harbin. - Highlights: • Two real cases reflect the temperature and flow control situation of heating systems in China. • Pre-set radiator valves with automatic balancing valves create dynamic hydraulic balance. • IDA-ICE simulation shows 17% heat saving and 48% pump electricity saving. • This approach can improve the comfort level of multi-storey/high-rise residential buildings. • This approach can reduce excess heat supply and bring out positive environmental impacts.

To Investigate the Influence of Building Envelope and Natural Ventilation on Thermal Heat Balance in Office Buildings in Warm and Humid Climate

Science.gov (United States)

Kini, Pradeep G.; Garg, Naresh Kumar; Kamath, Kiran

2017-07-01

India’s commercial building sector is witnessing robust growth. India continues to be a key growth market among global corporates and this is reflective in the steady growth in demand for prime office space. A recent trend that has been noted is the increase in demand for office spaces not just in major cities but also in smaller tier II and Tier III cities. Growth in the commercial building sector projects a rising trend of energy intensive mechanical systems in office buildings in India. The air conditioning market in India is growing at 25% annually. This is due to the ever increasing demand to maintain thermal comfort in tropical regions. Air conditioning is one of the most energy intensive technologies which are used in buildings. As a result India is witnessing significant spike in energy demand and further widening the demand supply gap. Challenge in India is to identify passive measures in building envelope design in office buildings to reduce the cooling loads and conserve energy. This paper investigates the overall heat gain through building envelope components and natural ventilation in warm and humid climate region through experimental and simulation methods towards improved thermal environmental performance.

A Solar Heating and Cooling System in a Nearly Zero-Energy Building: A Case Study in China

Directory of Open Access Journals (Sweden)

Zhifeng Sun

2017-01-01

Full Text Available The building sector accounts for more than 40% of the global energy consumption. This consumption may be lowered by reducing building energy requirements and using renewable energy in building energy supply systems. Therefore, a nearly zero-energy building, incorporating a solar heating and cooling system, was designed and built in Beijing, China. The system included a 35.17 kW cooling (10-RT absorption chiller, an evacuated tube solar collector with an aperture area of 320.6 m2, two hot-water storage tanks (with capacities of 10 m3 and 30 m3, respectively, two cold-water storage tanks (both with a capacity of 10 m3, and a 281 kW cooling tower. Heat pump systems were used as a backup. At a value of 25.2%, the obtained solar fraction associated with the cooling load was close to the design target of 30%. In addition, the daily solar collector efficiency and the chiller coefficient of performance (COP varied from 0.327 to 0.507 and 0.49 to 0.70, respectively.

Natural Ventilation: A Mitigation Strategy to Reduce Overheating In Buildings under Urban Heat Island Effect in South American Cities

Science.gov (United States)

Palme, Massimo; Carrasco, Claudio; Ángel Gálvez, Miguel; Inostroza, Luis

2017-10-01

Urban heat island effect often produces an increase of overheating sensation inside of buildings. To evacuate this heat, the current use of air conditioning increases the energy consumption of buildings. As a good alternative, natural ventilation is one of the best strategies to obtain indoor comfort conditions, even in summer season, if buildings and urban designs are appropriated. In this work, the overheating risk of a small house is evaluated in four South American cities: Guayaquil, Lima, Antofagasta and Valparaíso, with and without considering the UHI effect. Then, natural ventilation is assessed in order to understand the capability of this passive strategy to assure comfort inside the house. Results show that an important portion of the indoor heat can be evacuated, however the temperature rising (especially during the night) due to UHI can generate a saturation effect if appropriate technical solutions, like the increase in the air speed that can be obtained with good urban design, are not considered.

Geothermal heat pump performance

Energy Technology Data Exchange (ETDEWEB)

Boyd, Tonya L.; Lienau, Paul J.

1995-01-01

Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to customers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market penetration, incentive programs, and benefits.

Geothermal Heat Pump Performance

Energy Technology Data Exchange (ETDEWEB)

Boyd, Tonya L.; Lienau, Paul J.

1995-01-01

Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to customers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market penetration, incentive programs, and benefits.

Feasibility study on the St. Petersburg City heat and electric cogeneration plant No.2, etc. scrap and build project

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

For the purpose of reducing greenhouse effect gas emissions in line with the Joint Implementation, a survey was made of the scrap and build project for the superannuated Central Heat Power Station in St. Petersburg City. The survey team visited the relevant sites twice during 1999. The team drafted an improvement plan afterwards and presented it to the Russian counterpart, LENENEGRO. Based on the discussions with LENENEGRO, it was determined that the proposed combined cycle cogeneration plant would contain three 67MW-class gas turbines, three heat recovery steam generators and one back pressure turbine to achieve the generation capacity of approximately 200MW and heat supply capacity of 200G cal/hr. The total investment required for this project is about 140 million dollars. The term of the construction work is estimated at 36 months. It is estimated that the implementation of the project will reduce 1,481,979 tons of CO2 per year, or a total of 40,013,434 tons in 27 years after the commencement of operation. In addition, the terminal power generation efficiency will be improved from the current 18.68% to 41%, which leads to an annual fuel saving of 546,301 tons of crude oil or its equivalent. (NEDO)

The Polyvalent Heat Supply System for Experimental Building of the Passive Type (area of 300 m2 Based on Renewable and Alternative Energy Sources

Directory of Open Access Journals (Sweden)

Basok, B.I.

2014-11-01

Full Text Available Results of the development and implementation of heat supply system for experimental building of the passive type are presented, optimal operating conditions are investigated, guidelines for the creation of heat supply systems for passive type buildings are provided.

Novel Methods to Explore Building Energy Sensitivity to Climate and Heat Waves Using PNNL's BEND Model

Science.gov (United States)

Burleyson, C. D.; Voisin, N.; Taylor, T.; Xie, Y.; Kraucunas, I.

2017-12-01

The DOE's Pacific Northwest National Laboratory (PNNL) has been developing the Building ENergy Demand (BEND) model to simulate energy usage in residential and commercial buildings responding to changes in weather, climate, population, and building technologies. At its core, BEND is a mechanism to aggregate EnergyPlus simulations of a large number of individual buildings with a diversity of characteristics over large spatial scales. We have completed a series of experiments to explore methods to calibrate the BEND model, measure its ability to capture interannual variability in energy demand due to weather using simulations of two distinct weather years, and understand the sensitivity to the number and location of weather stations used to force the model. The use of weather from "representative cities" reduces computational costs, but often fails to capture spatial heterogeneity that may be important for simulations aimed at understanding how building stocks respond to a changing climate (Fig. 1). We quantify the potential reduction in temperature and load biases from using an increasing number of weather stations across the western U.S., ranging from 8 to roughly 150. Using 8 stations results in an average absolute summertime temperature bias of 4.0°C. The mean absolute bias drops to 1.5°C using all available stations. Temperature biases of this magnitude translate to absolute summertime mean simulated load biases as high as 13.8%. Additionally, using only 8 representative weather stations can lead to a 20-40% bias of peak building loads under heat wave or cold snap conditions, a significant error for capacity expansion planners who may rely on these types of simulations. This analysis suggests that using 4 stations per climate zone may be sufficient for most purposes. Our novel approach, which requires no new EnergyPlus simulations, could be useful to other researchers designing or calibrating aggregate building model simulations - particularly those looking at

Heating great residential units with combustion-motor heat pumps

Energy Technology Data Exchange (ETDEWEB)

Vossen, W

1982-10-01

Economic usage of combustion-motor heat pumps requires: reliable technology and delivery of the heat pump; design and operation. The heat pump must be integrated perfectly into the heating system. This contributions is based on a three-year operational experience with over 150 heat pumps used mainly in residential and administrative buildings (plus commercial buildings, swimming pools, sport centres etc.). These are heat pumps operating on the compression principle with natural gas, liquid gas, or fuel oil.

Thermal mass impact on energy performance of a low, medium and heavy mass building in Belgrade

Directory of Open Access Journals (Sweden)

Anđelković Bojan V.

2012-01-01

Full Text Available Heavy mass materials used in building structures and architecture can significantly affect building energy performance and occupant comfort. The purpose of this study was to investigate if thermal mass can improve the internal environment of a building, resulting in lower energy requirements from the mechanical systems. The study was focused on passive building energy performance and compared annual space heating and cooling energy requirements for an office building in Belgrade with several different applications of thermal mass. A three-dimensional building model was generated to represent a typical office building. Building shape, orientation, glazing to wall ratio, envelope insulation thickness, and indoor design conditions were held constant while location and thickness of building mass (concrete was varied between cases in a series of energy simulations. The results were compared and discussed in terms of the building space heating and cooling energy and demand affected by thermal mass. The simulation results indicated that with addition of thermal mass to the building envelope and structure: 100% of all simulated cases experienced reduced annual space heating energy requirements, 67% of all simulated cases experienced reduced annual space cooling energy requirements, 83% of all simulated cases experienced reduced peak space heating demand and 50% of all simulated cases experienced reduced peak space cooling demand. The study demonstrated that there exists a potential for reducing space heating and cooling energy requirements with heavy mass construction in the analyzed climate region (Belgrade, Serbia.

General-purpose heat source safety verification test series: SVT-11 through SVT-13

International Nuclear Information System (INIS)

George, T.G.; Pavone, D.

1986-05-01

The General-Purpose Heat Source (GPHS) is a modular component of the radioisotope thermoelectric generator that will provide power for the Galileo and Ulysses (formerly ISPM) space missions. The GPHS provides power by transmitting the heat of 238 Pu α-decay to an array of thermoelectric elements. Because the possibility of an orbital abort always exists, the heat source was designed and constructed to minimize plutonia release in any accident environment. The Safety Verification Test (SVT) series was formulated to evaluate the effectiveness of GPHS plutonia containment after atmospheric reentry and Earth impact. The first two reports (covering SVT-1 through SVT-10) described the results of flat, side-on, and angular module impacts against steel targets at 54 m/s. This report describes flat-on module impacts against concrete and granite targets, at velocities equivalent to or higher than previous SVTs

An analysis on how proposed requirements for near zero energy buildings manages PV electricity in combination with two different types of heat pumps and its policy implications – A Swedish example

International Nuclear Information System (INIS)

Thygesen, Richard; Karlsson, Björn

2017-01-01

This paper presents an analysis on how exhaust air- and ground source- heat pumps in combination with PV-systems affects the specific energy demand of buildings with the proposed Swedish near zero energy building definition and its policy implications. It also presents a method on how to estimate the contribution from the photovoltaic-system on the reduction of the specific energy demand of the building. A challenge with the proposed near zero energy building definition is that it is not clearly defined how it manages photovoltaic electricity as a mean to reduce the specific energy demand of buildings. The results suggest that the building with the ground source heat pump and heat recovery ventilation has the lowest specific energy demand. The proposed definition will give an advantage to system combinations comprised of heat pumps and PV-systems and this will lead to the possibility to build less insulated buildings with higher heat losses than for a building with a non-electrical heating system. A higher share of heat pumps can lead to lower electricity production in Sweden because of lost heating loads in district heating systems and a higher electricity demand. - Highlights: • We analyzed how the proposed Swedish NZE building definition manages PV electricity. • The building with a GSHP has the lowest specific energy demand. • Two different assumptions on the usage of PV electricity was used. • The difference between the two assumptions is 6 kWh/m"2 for both the GSHP and EAHP.

Low-energy office buildings using existing technology. Simulations with low internal heat gains

Energy Technology Data Exchange (ETDEWEB)

Flodberg, Kajsa; Blomsterberg, Aake; Dubois, Marie-Claude [Lund Univ. (Sweden). Div. of Energy and Building Design

2012-11-01

Although low-energy and nearly zero-energy residential houses have been built in Sweden in the past decade, there are very few examples of low-energy office buildings. This paper investigates the design features affecting energy use in office buildings and suggests the optimal low-energy design from a Swedish perspective. Dynamic simulations have been carried out with IDA ICE 4 on a typical narrow office building with perimeter cell rooms. The results from the parametric study reveal that the most important design features for energy saving are demand-controlled ventilation as well as limited glazing on the facade. Further energy-saving features are efficient lighting and office equipment which strongly reduce user-related electricity and cooling energy. Together, the simulation results suggest that about 48% energy can be saved compared to a new office building built according to the Swedish building code. Thus, it is possible, using a combination of simple and well-known building technologies and configurations, to have very low energy use in new office buildings. If renewable energy sources, such as solar energy and wind power, are added, there is a potential for the annual energy production to exceed the annual energy consumption and a net zero-energy building can be reached. One aspect of the results concerns user-related electricity, which becomes a major energy post in very low-energy offices and which is rarely regulated in building codes today. This results not only in high electricity use, but also in large internal heat gains and unnecessary high cooling loads given the high latitude and cold climate. (orig.)

Current status of and problems in ice heat storage systems contributing to improving load rate. Air conditioning system utilizing ice heat storage and building frame storage (Takenaka Corporation); Fukaritsu kaizen ni kokensuru kori chikunetsu system no genjo to kadai. Kori chikunetsu to kutai chikunetsu wo riyoshita kucho system

Energy Technology Data Exchange (ETDEWEB)

Inoue, Y.; Yoshitake, Y. [Takenaka Corp., Osaka (Japan)

1998-02-01

Development was made on a new air conditioning system, `building frame heat storage air conditioning system`, which combines an ice heat storage system with a building frame heat storage. With the building frame heat storage system, a damper is installed on an indoor device to blow cold air from the air conditioner onto slabs on the upper floor during nighttime power generating period. Heat is stored in beams, pillars and walls, and the shell absorbs and dissipates heat during daytime. Since general office buildings consume primary energy at 22.8% for heat source and 26.9% for transportation, which is greater, a natural coolant circulation type air conditioning system was developed as an air conditioning system for the secondary side. This made the building frame heat regeneration possible for the first time. With regard to heat storage quantity and heat dissipation quantity, the quantity of heat which can be stored during nighttime (10 hours) and dissipated during air conditioning using period in daytime (10 hours) is 80% of the stored heat quantity. This system was installed in a building in Kobe City. As a result of the measurement, it was found that indoor heat load reduction rate as a result of using the building frame heat storage was 24% or more in summer and 80% or more in winter. 7 figs., 2 tabs.

Low-Cost Gas Heat Pump for Building Space Heating

Energy Technology Data Exchange (ETDEWEB)

Garrabrant, Michael [Stone Mountain Technologies, Inc., Johnson City, TN (United States); Keinath, Christopher [Stone Mountain Technologies, Inc., Johnson City, TN (United States)

2016-10-11

Gas-fired residential space heating in the U.S is predominantly supplied by furnaces and boilers. These technologies have been approaching their thermodynamic limit over the past 30 years and improvements for high efficiency units have approached a point of diminishing return. Electric heat pumps are growing in popularity but their heating performance at low ambient temperatures is poor. The development of a low-cost gas absorption heat pump would offer a significant improvement to current furnaces and boilers, and in heating dominated climate zones when compared to electric heat pumps. Gas absorption heat pumps (GAHP) exceed the traditional limit of thermal efficiency encountered by typical furnaces and boilers, and maintain high levels of performance at low ambient temperatures. The project team designed and demonstrated two low-cost packaged prototype GAHP space heating systems during the course of this investigation. Led by Stone Mountain Technologies Inc. (SMTI), with support from A.O. Smith, and the Gas Technology Institute (GTI), the cross-functional team completed research and development tasks including cycle modeling, 8× scaling of a compact solution pump, combustion system development, breadboard evaluation, fabrication of two packaged prototype units, third party testing of the first prototype, and the evaluation of cost and energy savings compared to high and minimum efficiency gas options. Over the course of the project and with the fabrication of two Alpha prototypes it was shown that this technology met or exceeded most of the stated project targets. At ambient temperatures of 47, 35, 17 and -13°F the prototypes achieved gas based coefficients of performance of 1.50, 1.44, 1.37, and 1.17, respectively. Both units operated with parasitic loads well below the 750 watt target with the second Alpha prototype operating 75-100 watts below the first Alpha prototype. Modulation of the units at 4:1 was achieved with the project goal of 2:1 modulation

Sustainable Buildings in Interaction

DEFF Research Database (Denmark)

Elle, Morten

2007-01-01

The first attempts to build sustainable buildings in Denmark were typically located on the countryside. The basic idea was to create buildings that were independent of the technical infrastructure. District heating has, however, been the dominating solution to heating in buildings in Denmark......, and the focus on sustainable building have gradually turned from special houses on the countryside to normally looking houses in the urban fabric, integrated in the technical infrastructure. Some new built urban areas in Denmark will, however, not have to be supplied with district heating – these developments...... are going to consist of passive houses. The first sustainable buildings were built by their users, and the user – building interaction still play a decisive role for the performance of the present sustainable buildings. The users have to understand how the building functions. Urban design is essential...

Linear concentrating collector as an air heater in the heating system of building in Polish climatic conditions

Directory of Open Access Journals (Sweden)

Nemś Magdalena

2016-01-01

Full Text Available The article presents the analysis of the performance of a concentrating collector in the heating system of a residential building. Air was used as the working fluid. The heating requirements of the building were determined for each day of the year. The amount of direct irradiation reaching the absorber’s surface on all the days of the year was determined with the use of hourly meteorological data for Wroclaw, shared by the Ministry of Infrastructure and Growth. It was assumed that the collector is equipped with a tracking system working in one axis. Calculations and comparisons were made for the amount of solar irradiation for three values of the receiver’s inclination angle: β1=60°, β2=90° and β3=30°. Statistical method was used in order to determine the optimum inclination of the mirror and the amount of flowing air. This method involves creating a plan of experiment with three levels of changeability for two input factors. In the last stage, the amount of heat obtained from the installation during all the days of the year was analysed. The gains were juxtaposed on the diagram with the building’s heat demand. The analysis has shown that the heat requirements can be met only partially.

Solar Process Heat Basics | NREL

Science.gov (United States)

Process Heat Basics Solar Process Heat Basics Commercial and industrial buildings may use the same solar technologies-photovoltaics, passive heating, daylighting, and water heating-that are used for residential buildings. These nonresidential buildings can also use solar energy technologies that would be

'Eco-house 99' - Full-scale demonstration of solar walls with building integrated heat storages

Energy Technology Data Exchange (ETDEWEB)

Hummelshoej, R.M.; Rahbek, J.E. [COWI Consulting Engineers and Planners AS (Denmark)

2000-07-01

A critical issue for solar systems in northern latitudes is the economic profitability. It is often said that the techniques for solar utilisation are expensive and unprofitable. This is, however, not always the case. A new project with 59 low energy terrace houses was carried out in Kolding, Denmark. The houses are designed as ecological buildings with emphasis on total economy based on low operation and maintenance costs, energy conservation and passive/hybrid solar utilisation. Besides direct solar gain through windows, each house has a solar wall of 6-8.5 m{sup 2} on the south facade. The solar walls are used both for heating of ventilation air and for space heating. The solar walls deliver heat to the dwellings during the heating season. To optimise the energy utilisation from the solar walls, the energy is stored internally in building integrated heat storages. Two different new types of prefabricated heat storages are built into the houses. One is an internal concrete wall with embedded ventilation pipes, and the other is a hollow concrete element with integrated stone bed. The heat storages are mainly designed to store solar energy from the day to the evening and the night. Because the solar walls and the heat storages have been a part of the design process from the start, the additional expenses are as low as 30-140 Euro/m{sup 2} solar wall compared with the alternative facade. This is far less than what it costs to add a solar wall on an existing building. Measurements over one year show that the yield of the solar walls is in the range of 115-125 kWh/m{sup 2}/year as expected. With the actual financing, the annual payment of the additional expenses for the solar systems is between 1-6 Euro/m{sup 2} solar wall, while the annual savings are about 5 Euro/year/m{sup 2} (with an energy price of 0.042 Euro/kWh). Dependent on which alternative facade construction the solar wall system is compared with, the profit of the system is in the range of 1 to +4 Euro

Dynamic Heat Storage and Cooling Capacity of a Concrete Deck with PCM and Thermally Activated Building System

DEFF Research Database (Denmark)

Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

2012-01-01

This paper presents a heat storage and cooling concept that utilizes a phase change material (PCM) and a thermally activated building system (TABS) implemented in a hollow core concrete deck. Numerical calculations of the dynamic heat storage capacity of the hollow core concrete deck element...... in the article highlight the potential of using TABS and PCM in a prefabricated concrete deck element....

Dynamics of the cross flow heat exchanger for heating purposes

Energy Technology Data Exchange (ETDEWEB)

Mueller, K [Karlsruhe Univ. (TH) (Germany, F.R.). Inst. fuer Mess- und Regelungstechnik mit Maschinenlaboratorium

1980-09-01

A series of publications is available on the dynamic behaviour of heat exchangers (or heat transmitters, respectively), the subject of which is to deal with direct methods or with refined starting models for this general theme. The bridging between both these manners of advance remained as a problem. The author tried in his own investigation to solve the problem, and indeed by the selection of the correct starting model. He succeeded in this way, in that he removed conceptually a finned pipe from an arbitrary place of a heat exchanger and, furthermore, cut out from this particular pipe an arbitrary section. This section now does not stand alone for itself because the processes, which occur upstream of this section at the air-side and the water-side, are the input quantities of the section, which changes them due to its static and dynamic behaviour and emits them again as output quantities. The author, therefore, treats at first the dynamic behaviour of the section, which is represented in a signal flow diagram and which is used to derive approximate solutions from it. Furthermore, the author discusses the evident derivation of the total behaviour of heat exchangers.

Improving Thermal Performance of a Residential Building, Related to Its Orientations - A Case Study

Science.gov (United States)

Akshaya, S.; Harish, S.; Arthy, R.; Muthu, D.; Venkatasubramanian, C.

2017-07-01

Urban planners and stakeholders require knowledge about the effectiveness of city-scale climate adaptation measures in order to develop climate resilient cities and to push forward the political process for the implementation of climate adaptation strategies. This study examines the impact of modifications in orientation of buildings with respect to heat load. Heat load calculation is a mathematical process to determine the best capacity, application and style of HVAC system. The purpose is to ensure energy efficiency while also maximizing comfort inside the building. This study of load calculation is essential for a building because it helps to pick the best orientation and focuses to find an orientation that will reduce energy due to direct solar radiation. One of the factors affecting this assessment is the latitude of the location. The heat gain is effective through walls and fenestration. Improper management through ineffective orientation of the building’s natural heat gain leads to excessive consumption of energy in the form of CL. The total heat gain for the above factors is calculated with the equations and assumptions as per ASHRAE code. After the calculation of heat load for different orientations, the best suited orientation of the building is found. By altering the building to suitable orientation, the dependence on electrical equipment can be minimized and thereby helps in energy conservation.

Building-integrated renewable energy policy analysis in China

Institute of Scientific and Technical Information of China (English)

姚春妮; 郝斌

2009-01-01

With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.

Study and Optimization of Design Parameters in Water Loop Heat Pump Systems for Office Buildings in the Iberian Peninsula

Directory of Open Access Journals (Sweden)

Francisco Javier Fernández

2017-11-01

Full Text Available Water loop heat pump (WLHP air conditioning systems use heat pumps connected to a common water circuit to fulfill the energy demands of different thermal zones in a building. In this study, the energy consumption was analyzed for the air conditioning of an office building in the typical climate of four important cities of the Iberian Peninsula. The energy consumption of one water loop heat pump system was compared with a conventional water system. Two design parameters, the range in the control temperatures and the water loop thermal storage size, were tested. Energy redistribution is an important advantage of the WLHP system, but significant savings came from high efficiency parameters in the heat pumps and minor air flow rates in the cooling tower. The low thermal level in the water loop makes this technology appropriate to combine with renewable sources. Using natural gas as the thermal energy source, a mean decrease in CO2 emissions of 8.1% was reached. Simulations showed that the installation of big thermal storage tanks generated small energy savings. Besides, the total annual consumption in buildings with high internal loads can be reduced by keeping the water loop as cool as possible.

Analysis and proposal of implementation effects of heat metering and energy efficiency retrofit of existing residential buildings in northern heating areas of China in “the 11th Five-Year Plan” period

International Nuclear Information System (INIS)