WorldWideScience

Sample records for radiant energy operations

  1. Nonimaging radiant energy device

    Winston, Roland; Ning, Xiaohui

    1993-01-01

    A nonimaging radiant energy device may include a hyperbolically shaped reflective element with a radiant energy inlet and a radiant energy outlet. A convex lens is provided at the radiant energy inlet and a concave lens is provided at the radiant energy outlet. Due to the provision of the lenses and the shape of the walls of the reflective element, the radiant energy incident at the radiant energy inlet within a predetermined angle of acceptance is emitted from the radiant energy outlet exclusively within an acute exit angle. In another embodiment, the radiant energy device may include two interconnected hyperbolically shaped reflective elements with a respective convex lens being provided at each aperture of the device.

  2. Performance of Radiant Heating Systems of Low-Energy Buildings

    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.

  3. Direct conversion of infrared radiant energy for space power applications

    Finke, R. C.

    1982-01-01

    A proposed technology to convert the earth radiant energy (infrared albedo) for spacecraft power is presented. The resultant system would eliminate energy storage requirements and simplify the spacecraft design. The design and performance of a infrared rectenna is discussed.

  4. Radiant Barriers Save Energy in Buildings

    2014-01-01

    Langley Research Center needed to coat the Echo 1 satellite with a fine mist of vaporized metal, and collaborated with industry to create "radiant barrier technology." In 2010, Ryan Garrett learned about a new version of the technology resistant to oxidation and founded RadiaSource in Ogden, Utah, to provide the NASA-derived technology for applications in homes, warehouses, gymnasiums, and agricultural settings.

  5. Design of energy efficient building with radiant slab cooling

    Tian, Zhen

    2007-12-01

    Air-conditioning comprises a substantial fraction of commercial building energy use because of compressor-driven refrigeration and fan-driven air circulation. Core regions of large buildings require year-round cooling due to heat gains from people, lights and equipment. Negative environmental impacts include CO2 emissions from electric generation and leakage of ozone-depleting refrigerants. Some argue that radiant cooling simultaneously improves building efficiency and occupant thermal comfort, and that current thermal comfort models fail to reflect occupant experience with radiant thermal control systems. There is little field evidence to test these claims. The University of Calgary's Information and Communications Technology (ICT) Building, is a pioneering radiant slab cooling installation in North America. Thermal comfort and energy performance were evaluated. Measurements included: (1) heating and cooling energy use, (2) electrical energy use for lighting and equipment, and (3) indoor temperatures. Accuracy of a whole building energy simulation model was evaluated with these data. Simulation was then used to compare the radiant slab design with a conventional (variable air volume) system. The radiant system energy performance was found to be poorer mainly due to: (1) simultaneous cooling by the slab and heating by other systems, (2) omission of low-exergy (e.g., groundwater) cooling possible with the high cooling water temperatures possible with radiant slabs and (3) excessive solar gain and conductive heat loss due to the wall and fenestration design. Occupant thermal comfort was evaluated through questionnaires and concurrent measurement of workstation comfort parameters. Analysis of 116 sets of data from 82 occupants showed that occupant assessment was consistent with estimates based on current thermal comfort models. The main thermal comfort improvements were reductions in (1) local discomfort from draft and (2) vertical air temperature stratification. The

  6. Energy efficiency and indoor thermal perception. A comparative study between radiant panel and portable convective heaters

    Ali, Ahmed Hamza H.; Morsy, Mahmoud Gaber [Department of Mechanical Engineering, Faculty of Engineering, Assiut University, Assiut, 71516 (Egypt)

    2010-11-15

    This study investigates experimentally the thermal perception of indoor environment for evaluating the ability of radiant panel heaters to produce thermal comfort for space occupants as well as the energy consumption in comparison with conventional portable natural convective heaters. The thermal perception results show that, compared with conventional convection heater, a radiantly heated office room maintains a lower ambient air temperature while providing equal levels of thermal perception on the thermal dummy head as the convective heater and saves up to 39.1% of the energy consumption per day. However, for human subjects' vote experiments, the results show that for an environmentally controlled test room at outdoor environment temperatures of 0C and 5C, using two radiant panel heaters with a total capacity of 580 W leads to a better comfort sensation than the conventional portable natural convective heater with a 670 W capacity, with an energy saving of about 13.4%. In addition, for an outdoor environment temperature of 10C, using one radiant panel heater with a capacity of 290 W leads to a better comfort sensation than the conventional convection heater with a 670 W capacity, with an energy saving of about 56.7%. From the analytical results, it is found that distributing the radiant panel heater inside the office room, one on the wall facing the window and the other on the wall close to the window, provides the best operative temperature distribution within the room.

  7. ''Super-radiant'' states in intermediate energy nuclear physics

    Auerbach, N.

    1994-01-01

    A ''super-radiant'' state emerges when, under certain conditions, one or a few ''internal'' states acquire a large collective decay width due to the coupling to one or a few ''external'' decay channels. The rest of the internal states are ''stripped'' of their decay width and become long lived quasistationary states. The essentials of such mechanism and its possible role in intermediate energy nuclear physics are discussed in this work

  8. Radiant energy collection and conversion apparatus and method

    Hunt, A.J.

    The apparatus for collecting radiant energy and converting to alternate energy forms includes a housing having an interior space and a radiation transparent window allowing solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past the window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  9. Radiant energy during infrared neural stimulation at the target structure

    Richter, Claus-Peter; Rajguru, Suhrud; Stafford, Ryan; Stock, Stuart R.

    2013-03-01

    Infrared neural stimulation (INS) describes a method, by which an infrared laser is used to stimulate neurons. The major benefit of INS over stimulating neurons with electrical current is its spatial selectivity. To translate the technique into a clinical application it is important to know the energy required to stimulate the neural structure. With this study we provide measurements of the radiant exposure, at the target structure that is required to stimulate the auditory neurons. Flat polished fibers were inserted into scala tympani so that the spiral ganglion was in front of the optical fiber. Angle polished fibers were inserted along scala tympani, and rotating the beveled surface of the fiber allowed the radiation beam to be directed perpendicular to the spiral ganglion. The radiant exposure for stimulation at the modiolus for flat and angle polished fibers averaged 6.78+/-2.15 mJ/cm2. With the angle polished fibers, a 90º change in the orientation of the optical beam from an orientation that resulted in an INS-evoked maximum response, resulted in a 50% drop in the response amplitude. When the orientation of the beam was changed by 180º, such that it was directed opposite to the orientation with the maxima, minimum response amplitude was observed.

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

    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.

  11. Influence of increment thickness on radiant energy and microhardness of bulk-fill resin composites.

    Karacolak, Gamze; Turkun, L Sebnem; Boyacioglu, Hayal; Ferracane, Jack L

    2018-03-30

    Determining the energy transferred at the bottom of eleven bulk-fill resin composites, comparing top and bottom microhardness's and evaluating the correlation between microhardness and radiant energy were aimed. Samples were placed over the bottom sensor of a visible light transmission spectrophotometer and polymerized for 20 s. The bottom and top Knoop microhardness were measured. Paired t-test and correlation analysis were used for statistics (p≤0.05). In all groups, the bottom radiant energy decreased significantly with increasing thickness. For groups of Aura 2 mm, X-tra Fil 2 and 4 mm, SDR 2 and 4 mm, X-tra Base 2 mm no significant difference was found between top and bottom microhardness. For the bottom levels of Aura, X-tra Fil, Filtek Bulk-Fill Posterior, SDR, X-tra Base groups no significant difference was found between the microhardness's of 2 and 4 mm thicknesses. For X-tra Fil, Tetric Evo Ceram Bulk-Fill, Filtek Bulk-Fill Flowable and Z100 groups radiant energy affected positively the microhardness.

  12. Effects of Floor Covering Resistance of a Radiant Floor on System Energy and Exergy Performances

    Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

    2016-01-01

    Floor covering resistance (material and thickness) can be influenced by subjective choices (architectural design, interior design, texture, etc.) with significant effects on the performance of a radiant heating and cooling system. To study the effects of floor covering resistance on system...... performance, a water-based radiant floor heating and cooling system (dry, wooden construction) was considered to be coupled to an air-to-water heat pump, and the effects of varying floor covering resistances (0.05 m2K/W, 0.09 m2K/W and 0.15 m2K/W) on system performance were analyzed in terms of energy...... and exergy. In order to achieve the same heating and cooling outputs, higher average water temperatures are required in the heating mode (and lower temperatures in the cooling mode) with increasing floor covering resistance. These temperature requirements decrease the heat pump’s performance (lower...

  13. Radiant Research. Institute for Energy Technology 1948-98

    Njoelstad, Olav

    1999-01-01

    Institutt for Atomenergi (IFA), or Institute for Atomic Energy, at Kjeller, Norway, was founded in 1948. The history of the institute as given in this book was published in 1999 on the occasion of the institute's 50th anniversary. The scope of the institute was to do research and development as a foundation for peaceful application of nuclear energy and radioactive substances in Norway. The book tells the story of how Norway in 1951 became the first country after the four superpowers and Canada to have its own research reactor. After the completion of the reactor, the institute experienced a long and successful period and became the biggest scientific and technological research institute in Norway. Three more reactors were built, one in Halden and two at Kjeller. Plans were developed to build nuclear powered ships and nuclear power stations. It became clear, however, in the 1970s, that there was no longer political support for nuclear power in Norway, and it was necessary for the institute to change its research profile. In 1980, the institute changed its name to Institutt for energiteknikk (IFE), or Institute for energy technology, to signal the broadened scope. The book describes this painful but successful readjustment and shows how IFE in the 1980s and 1990s succeeded in using its special competence from the nuclear field to establish special competence in new research fields with great commercial potential

  14. Energy flow and thermal comfort in buildings: Comparison of radiant and air-based heating & cooling systems

    Le Dréau, Jérôme

    is based on both radiation and convection. This thesis focuses on characterizing the heat transfer from the terminal towards the space and on the parameters influencing the effectiveness of terminals. Therefore the comfort conditions and energy consumption of four types of terminals (active chilled beam...... losses, and an air-based terminal might be more energy-efficient than a radiant terminal (in terms of delivered energy). Regarding comfort, a similar global level has been observed for the radiant and air-based terminals in both numerical and experimental investigations. But the different terminals did...... not achieve the same uniformity in space. The active chilled beam theoretically achieves the most uniform comfort conditions (when disregarding the risk of draught), followed by the radiant ceiling. The least uniform conditions were obtained with the cooled floor due to large differences between the sitting...

  15. Energy flow and thermal comfort in buildings: Comparison of radiant and air-based heating & cooling systems

    Le Dréau, Jérôme

    Heating and cooling terminals can be classified in two main categories: convective terminals (e.g air conditioning, active chilled beam, fan coil) and radiant terminals. The two terminals have different modes of heat transfer: the first one is mainly based on convection, whereas the second one...... is based on both radiation and convection. This thesis focuses on characterizing the heat transfer from the terminal towards the space and on the parameters influencing the effectiveness of terminals. Therefore the comfort conditions and energy consumption of four types of terminals (active chilled beam...... losses, and an air-based terminal might be more energy-efficient than a radiant terminal (in terms of delivered energy). Regarding comfort, a similar global level has been observed for the radiant and air-based terminals in both numerical and experimental investigations. But the different terminals did...

  16. Solar–terrestrial radiant-energy regimes and temperature anomalies of natural and artificial turfs

    Jim, C.Y.

    2016-01-01

    Highlights: • Solar and terrestrial radian energy regimes affect temperature response of sports turfs. • Adjacent natural and artificial turfs were monitored with replications on sunny days. • Artificial turf has meager albedo, low specific heat and moisture to augment warming. • Artificial turf surface and substrate reach 70 °C but cool down effectively at night. • Artificial turf may induce heat stress on athletes in hot summer afternoon. - Abstract: Artificial turf can develop unusually high surface temperature on hot sunny days. Solar and terrestrial radiant energy regimes as key determinants of thermal performance deserve detailed investigation. This study evaluated six components of the radiant-energy environment of a natural turf (NT) and a contiguous artificial turf (AT) sports fields in Hong Kong: direct solar, reflected solar, net solar, sky thermal, ground thermal, and net thermal. Temperature was monitored at five positions: air at 150 cm, 50 cm and 15 cm height, turf surface, and substrate. The experiment included four replications, namely two summer sunny days, and two duplicated instrument sets at each turf site. The two sites reacted very differently to the same intense daily sum of solar radiation input of 23.70 MW m −2 with 9 h of bright sunshine (>120 W m −2 ), and daily sum of sky thermal radiation input of 38.59 MW m −2 . The maximum direct solar radiation reached 976.1 W m −2 at 1245 h. NT albedo of 0.23 vis-à-vis AT of merely 0.073, and higher moisture content and specific heat of NT materials, presented critical differences. The hydrophobic and generally dry plastic (polyethylene) pile-fibers and black rubber-granule infill materials have low specific heat. Intense incoming shortwave and longwave radiation absorbed readily by AT materials raised turf surface temperature to 70.2 °C and substrate 69.3 °C, in comparison with <40 °C at NT. A cascading warming effect was triggered, beginning with low albedo, high net solar

  17. Clouds and the Earth's Radiant Energy System (CERES) Data Products for Climate Research

    Kato, Seiji; Loeb, Norman G.; Rutan, David A.; Rose, Fred G.

    2015-01-01

    NASA's Clouds and the Earth's Radiant Energy System (CERES) project integrates CERES, Moderate Resolution Imaging Spectroradiometer (MODIS), and geostationary satellite observations to provide top-of-atmosphere (TOA) irradiances derived from broadband radiance observations by CERES instruments. It also uses snow cover and sea ice extent retrieved from microwave instruments as well as thermodynamic variables from reanalysis. In addition, these variables are used for surface and atmospheric irradiance computations. The CERES project provides TOA, surface, and atmospheric irradiances in various spatial and temporal resolutions. These data sets are for climate research and evaluation of climate models. Long-term observations are required to understand how the Earth system responds to radiative forcing. A simple model is used to estimate the time to detect trends in TOA reflected shortwave and emitted longwave irradiances.

  18. Numerical study of influence of different dispersed components of crystal cloud on transmission of radiant energy

    Shefer, Olga

    2017-11-01

    The calculated results of the transmission of visible and infrared radiation by an atmosphere layer involving ensembles of large preferentially oriented crystals and spherical particles are presented. To calculate extinction characteristics, the physical optics method and the Mie theory are applied. Among all atmospheric particles, both the small particles that are commensurable with the wavelength of the incident radiation and the large plates and the columns are distinguished by the most pronounced dependence of the transmission on spectra of radiant energy. The work illustrates features of influence of parameters of the particle size distribution, particle aspect ratios, orientation and particle refractive index, also polarization state of the incident radiation on the transmission. The predominant effect of the plates on the wavelength dependence of the transmission is shown. A separated and cooperative contributes of the large plates and the small volume shape particles to the common transmission by medium are considered.

  19. The Influence of a Radiant Panel System with Integrated Phase Change Material on Energy Use and Thermal Indoor Environment

    Nielsen, Lin Flemming; Bourdakis, Eleftherios; Kazanci, Ongun Berk

    2018-01-01

    This study examined the effect on energy use and thermal comfort when combining microencapsulated phase change material (PCM) with radiant ceiling panels in a two-person office. The performance of the system was studied during the cooling season in the climates of Copenhagen, Denmark, and Rome...

  20. Extinction of radiant energy by large atmospheric crystals with different shapes

    Shefer, Olga

    2016-01-01

    The calculated results of extinction characteristics of visible and infrared radiation for large semi-transparent crystals are obtained by hybrid technique, which is a combination of the geometric optics method and the physical optics method. Energy and polarization characteristics of the radiation extinction in terms of the elements of the extinction matrix for individual large crystals and ensemble of crystals are discussed. Influences of particle shapes, aspect ratios, parameters of size distribution, complex refractive index, orientation of crystals, wavelength, and the polarization state of an incident radiation on the extinction are illustrated. It is shown that the most expressive and stable features of energy and polarization characteristics of the extinction are observed in the midinfrared region, despite the fact that the ice particles significantly absorb the radiant energy of this spectrum. It is demonstrated that the polarized extinction characteristics can reach several tens of percent at IR wavelengths. For the large crystals, the conditions of occurrence of the spectral behavior of the extinction coefficient in the visible, near-IR, and mid-IR wavelength ranges are determined. - Highlights: • Method of physical optics is used at coherent sum of diffracted and refracted fields. • The extinction characteristics in terms of elements of extinction matrix are obtained. • Influence of shapes and sizes of large particles on the extinction is evaluated. • Conditions of occurrence of extinction features are determined.

  1. PERFORMANCE EVALUATION OF CEILING RADIANT COOLING SYSTEM IN COMPOSITE CLIMATE

    Sharma, Anuj [Malaviya National Institute of Technology (MNIT), Jaipur, India; Mathur, Jyotirmay [Malaviya National Institute of Technology (MNIT), Jaipur, India; Bhandari, Mahabir S [ORNL

    2015-01-01

    Radiant cooling systems are proving to be an energy efficient solution due to higher thermal capacity of cooling fluid especially for the buildings that require individual zone controls and where the latent loads are moderate. The Conventional air conditioners work at very low temperature i.e.5-8 c (refrigerant evaporator inlet) while the radiant cooling systems, also referred as high temperature cooling system, work at high temperatures i.e. 14-18 c. The radiant cooling systems can maintain lower MRT (Mean Radiant Temperature) as ceiling panels maintain uniform temperature gradient inside room and provide higher human comfort. The radiant cooling systems are relatively new systems and their operation and energy savings potential are not quantified for a large number of buildings and operational parameters. Moreover, there are only limited numbers of whole building simulation studies have been carried out for these systems to have a full confidence in the capability of modelling tools to simulate these systems and predict the impact of various operating parameters. Theoretically, savings achieve due to higher temperature set point of chilled water, which reduces chiller-running time. However, conventional air conditioner runs continuously to maintain requisite temperature. In this paper, experimental study for performance evaluation of radiant cooling system carried out on system installed at Malaviya National Institute of Technology Jaipur. This paper quantifies the energy savings opportunities and effective temperature by radiant cooling system at different chilled water flow rates and temperature range. The data collected/ analysed through experimental study will used for calibration and validation of system model of building prepared in building performance simulation software. This validated model used for exploring optimized combinations of key parameters for composite climate. These optimized combinations will used in formulation of radiant cooling system

  2. Clouds and Earth Radiant Energy System (CERES), a Review: Past, Present and Future

    Smith, G. L.; Priestley, K. J.; Loeb, N. G.; Wielicki, B. A.; Charlock, T. P.; Minnis, P.; Doelling, D. R.; Rutan, D. A.

    2011-01-01

    The Clouds and Earth Radiant Energy System (CERES) project s objectives are to measure the reflected solar radiance (shortwave) and Earth-emitted (longwave) radiances and from these measurements to compute the shortwave and longwave radiation fluxes at the top of the atmosphere (TOA) and the surface and radiation divergence within the atmosphere. The fluxes at TOA are to be retrieved to an accuracy of 2%. Improved bidirectional reflectance distribution functions (BRDFs) have been developed to compute the fluxes at TOA from the measured radiances with errors reduced from ERBE by a factor of two or more. Instruments aboard the Terra and Aqua spacecraft provide sampling at four local times. In order to further reduce temporal sampling errors, data are used from the geostationary meteorological satellites to account for changes of scenes between observations by the CERES radiometers. A validation protocol including in-flight calibrations and comparisons of measurements has reduced the instrument errors to less than 1%. The data are processed through three editions. The first edition provides a timely flow of data to investigators and the third edition provides data products as accurate as possible with resources available. A suite of cloud properties retrieved from the MODerate-resolution Imaging Spectroradiometer (MODIS) by the CERES team is used to identify the cloud properties for each pixel in order to select the BRDF for each pixel so as to compute radiation fluxes from radiances. Also, the cloud information is used to compute radiation at the surface and through the atmosphere and to facilitate study of the relationship between clouds and the radiation budget. The data products from CERES include, in addition to the reflected solar radiation and Earth emitted radiation fluxes at TOA, the upward and downward shortwave and longwave radiation fluxes at the surface and at various levels in the atmosphere. Also at the surface the photosynthetically active radiation

  3. Climate Model Evaluation using New Datasets from the Clouds and the Earth's Radiant Energy System (CERES)

    Loeb, Norman G.; Wielicki, Bruce A.; Doelling, David R.

    2008-01-01

    There are some in the science community who believe that the response of the climate system to anthropogenic radiative forcing is unpredictable and we should therefore call off the quest . The key limitation in climate predictability is associated with cloud feedback. Narrowing the uncertainty in cloud feedback (and therefore climate sensitivity) requires optimal use of the best available observations to evaluate and improve climate model processes and constrain climate model simulations over longer time scales. The Clouds and the Earth s Radiant Energy System (CERES) is a satellite-based program that provides global cloud, aerosol and radiative flux observations for improving our understanding of cloud-aerosol-radiation feedbacks in the Earth s climate system. CERES is the successor to the Earth Radiation Budget Experiment (ERBE), which has widely been used to evaluate climate models both at short time scales (e.g., process studies) and at decadal time scales. A CERES instrument flew on the TRMM satellite and captured the dramatic 1998 El Nino, and four other CERES instruments are currently flying aboard the Terra and Aqua platforms. Plans are underway to fly the remaining copy of CERES on the upcoming NPP spacecraft (mid-2010 launch date). Every aspect of CERES represents a significant improvement over ERBE. While both CERES and ERBE measure broadband radiation, CERES calibration is a factor of 2 better than ERBE. In order to improve the characterization of clouds and aerosols within a CERES footprint, we use coincident higher-resolution imager observations (VIRS, MODIS or VIIRS) to provide a consistent cloud-aerosol-radiation dataset at climate accuracy. Improved radiative fluxes are obtained by using new CERES-derived Angular Distribution Models (ADMs) for converting measured radiances to fluxes. CERES radiative fluxes are a factor of 2 more accurate than ERBE overall, but the improvement by cloud type and at high latitudes can be as high as a factor of 5

  4. Radiant Energy Measurements from a Scaled Jet Engine Axisymmetric Exhaust Nozzle for a Baseline Code Validation Case

    Baumeister, Joseph F.

    1994-01-01

    A non-flowing, electrically heated test rig was developed to verify computer codes that calculate radiant energy propagation from nozzle geometries that represent aircraft propulsion nozzle systems. Since there are a variety of analysis tools used to evaluate thermal radiation propagation from partially enclosed nozzle surfaces, an experimental benchmark test case was developed for code comparison. This paper briefly describes the nozzle test rig and the developed analytical nozzle geometry used to compare the experimental and predicted thermal radiation results. A major objective of this effort was to make available the experimental results and the analytical model in a format to facilitate conversion to existing computer code formats. For code validation purposes this nozzle geometry represents one validation case for one set of analysis conditions. Since each computer code has advantages and disadvantages based on scope, requirements, and desired accuracy, the usefulness of this single nozzle baseline validation case can be limited for some code comparisons.

  5. Thermal environment in simulated offices with convective and radiant cooling systems under cooling (summer) mode of operation

    Mustakallio, Panu; Bolashikov, Zhecho Dimitrov; Kostov, Kalin

    2016-01-01

    The thermal environment in a double office room and in a six-person meeting room obtained with chilled beam (CB), chilled beam with radiant panel (CBR), chilled ceiling with ceiling installed mixing ventilation (CCMV) and four desk partition-mounted local radiant cooling panels with mixing...... calculated. Manikin-based equivalent temperature (MBET) was determined by using two thermal manikins to identify the impact of the local thermal conditions generated by the studied systems on occupants' thermal perception. The results revealed that the differences in the thermal conditions achieved...

  6. Numerical Modeling of Conjugate Thermogravitational Convection in a Closed System with a Radiant Energy Source in Conditions of Convective-Radiative Heat Exchange at the External Boundary

    Nee Alexander

    2016-01-01

    Full Text Available Mathematical modeling of conjugate natural convection in a closed rectangular cavity with a radiant energy source in conditions of convective-radiative heat exchange at the external boundary was conducted. The radiant energy distribution was set by the Lambert’s law. Conduction and convection processes analysis showed that the air masses flow pattern is modified slightly over the time. The temperature increases in the gas cavity, despite the heat removal from the one of the external boundary. According to the results of the integral heat transfer analysis were established that the average Nusselt number (Nuav increasing occurs up to τ = 200 (dimensionless time. Further Nuav has changed insignificantly due to the temperature field equalization near the interfaces “gas – wall”.

  7. Modeling the transmitted and stored energy in multilayer protective clothing under low-level radiant exposure

    Su, Yun; He, Jiazhen; Li, Jun

    2016-01-01

    Highlights: • A numerical model from heating source to skin tissues through multilayer fabric system is developed. • The numerical model is comprehensively validated with experimental data. • The model is used to investigate the relationship between the transmitted and stored energy and the influencing factors. - Abstract: A finite difference model was introduced to simulate the transmitted and stored energy in firefighters' protective clothing exposed to low-level thermal radiation. The model domain consists of a three-layer fire-resistant fabric system (outer shell, moisture barrier, and thermal liner), the human skin, and the air gap between clothing and the skin. The model accounted for the relationship between the transmitted heat during the exposure and the discharged heat during the cooling-down period. The numerical model predictions were compared with experimental data. Additionally, the parameters that affect the transmitted and stored energy of protective clothing were investigated. The results demonstrate that for the typical multilayer firefighter protective clothing, the transmitted heat during exposure and the discharged heat after exposure totally determine the skin burn under low-level heat exposure, especially for third-degree skin burns. The findings obtained in this study can be used to engineer fabric systems that provide better protection for the stored thermal burn.

  8. Radiant energy dissipation during final storage of high-level radioactive waste in rock salt

    Ramthun, H.

    1981-08-01

    A final disposal concept is assumed where the high-active waste from 1400 t of uranium, remaining after conditioning, is solidified in borosilicate glass and distributed in 1.760 waste casks. These containers 1.2 m in height and 0.3 m in diameter are to be buried 10 years after the fuel is removed from the reactor in the 300 m deep boreholes of a salt dome. For this design the mean absorbed dose rates are calculated in the glass die (3.9 Gy/s), the steel mantle (0.26 Gy/s) and in the salt rock (0.12 Gy/s at a distance of 1 cm and 0.034 Gy/s at a distance of 9 cm from the container surface) valid at the beginning of disposal. The risk involved with these amounts of stored lattice energy is shortly discussed. (orig.) [de

  9. A determination of the absolute radiant energy of a Robertson-Berger meter sunburn unit

    DeLuisi, John J.; Harris, Joyce M.

    Data from a Robertson-Berger (RB) sunburn meter were compared with concurrent measurements obtained with an ultraviolet double monochromator (DM), and the absolute energy of one sunburn unit measured by the RB-meter was determined. It was found that at a solar zenith angle of 30° one sunburn unit (SU) is equivalent to 35 ± 4 mJ cm -2, and at a solar zenith angle of 69°, one SU is equivalent to 20 ± 2 mJ cm -2 (relative to a wavelength of 297 nm), where the rate of change is non-linear. The deviation is due to the different response functions of the RB-meter and the DM system used to simulate the response of human skin to the incident u.v. solar spectrum. The average growth rate of the deviation with increasing solar zenith angle was found to be 1.2% per degree between solar zenith angles 30 and 50° and 2.3% per degree between solar zenith angles 50 and 70°. The deviations of response with solar zenith angle were found to be consistent with reported RB-meter characteristics.

  10. Mathematical modelling, variational formulation and numerical simulation of the energy transfer process in a gray plate in the presence of a thermal radiant source

    Gama, R.M.S. da.

    1992-05-01

    The energy transfer process in a gray, opaque and rigid plate, heated by an external thermal radiant source, is considered. The source is regarded as a spherical black body, with radius a (a → 0) and uniform heat generation, placed above the plate. A mathematical model is constructed, assuming that the heat transfer from/to the plate takes place by thermal radiation. The obtained mathematical model is nonlinear. Is presented a suitable variational principle which is employed for simulating some particular cases. (author)

  11. Exergy metrication of radiant panel heating and cooling with heat pumps

    Kilkis, Birol

    2012-01-01

    Highlights: ► Rational Exergy Management Model analytically relates heat pumps and radiant panels. ► Heat pumps driven by wind energy perform better with radiantpanels. ► Better CO 2 mitigation is possible with wind turbine, heat pump, radiant panel combination. ► Energy savings and thermo-mechanical performance are directly linked to CO 2 emissions. - Abstract: Radiant panels are known to be energy efficient sensible heating and cooling systems and a suitable fit for low-exergy buildings. This paper points out the little known fact that this may not necessarily be true unless their low-exergy demand is matched with low-exergy waste and alternative energy resources. In order to further investigate and metricate this condition and shed more light on this issue for different types of energy resources and energy conversion systems coupled to radiant panels, a new engineering metric was developed. Using this metric, which is based on the Rational Exergy Management Model, true potential and benefits of radiant panels coupled to ground-source heat pumps were analyzed. Results provide a new perspective in identifying the actual benefits of heat pump technology in curbing CO 2 emissions and also refer to IEA Annex 49 findings for low-exergy buildings. Case studies regarding different scenarios are compared with a base case, which comprises a radiant panel system connected to a natural gas-fired condensing boiler in heating and a grid power-driven chiller in cooling. Results show that there is a substantial CO 2 emission reduction potential if radiant panels are optimally operated with ground-source heat pumps driven by renewable energy sources, or optimally matched with combined heat and power systems, preferably running on alternative fuels.

  12. Experimental evaluation of an active solar thermoelectric radiant wall system

    Liu, ZhongBing; Zhang, Ling; Gong, GuangCai; Han, TianHe

    2015-01-01

    Highlights: • A novel active solar thermoelectric radiant wall are proposed and tested. • The novel wall can control thermal flux of building envelope by using solar energy. • The novel wall can eliminate building envelop thermal loads and provide cooling capacity for space cooling. • Typical application issues including connection strategies, coupling with PV system etc. are discussed. - Abstract: Active solar thermoelectric radiant wall (ASTRW) system is a new solar wall technology which integrates thermoelectric radiant cooling and photovoltaic (PV) technologies. In ASTRW system, a PV system transfers solar energy directly into electrical energy to power thermoelectric cooling modes. Both the thermoelectric cooling modes and PV system are integrated into one enclosure surface as radiant panel for space cooling and heating. Hence, ASTRW system presents fundamental shift from minimizing building envelope energy losses by optimizing the insulation thickness to a new regime where active solar envelop is designed to eliminate thermal loads and increase the building’s solar gains while providing occupant comfort in all seasons. This article presents an experimental study of an ASTRW system with a dimension of 1580 × 810 mm. Experimental results showed that the inner surface temperature of the ASTRW is 3–8 °C lower than the indoor temperature of the test room, which indicated that the ASTRW system has the ability to control thermal flux of building envelope by using solar energy and reduce the air conditioning system requirements. Based on the optimal operating current of TE modules and the analysis based upon PV modeling theories, the number and type of the electrical connections for the TE modules in ASTRW system are discussed in order to get an excellent performance in the operation of the ASTRW system

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

    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

  14. Energy operations policy

    1993-01-01

    It is reported that energy policy was designed following the European Bank for Reconstruction and Development review of the most pressing energy issues confronting Central and Eastern Europe and the republics of the former Soviet Union. The main features of the policy described in the document set the general framework for the Bank's energy operations. Energy strategies for particular countries are designed as an integral part of the Bank's individual country strategies. Tabs

  15. Radiant cooling of an enclosure

    Chebihi, Abdeslam; Byun, Ki-Hong; Wen Jin; Smith, Theodore F.

    2006-01-01

    The purpose of this study is to analyze the potential for radiant cooling using the atmospheric sky window and to evaluate the desired characteristics of a radiant cooling material (RCM) applied to the ceiling window of a three-dimensional enclosure. The thermal characteristics of the system are governed by the geometry, ambient temperature, sky radiative temperature, amount of solar energy and its direction, heat transfer modes, wall radiative properties, and radiative properties of the RCMs. A semi-gray band analysis is utilized for the solar and infrared bands. The radiosity/irradiation method is used in each band to evaluate the radiant exchanges in the enclosure. The radiative properties for the RCM are varied in a parametric study to identify the desired properties of RCMs. For performance simulation of real RCMs, the radiative properties are calculated from spectral data. The desired solar property is a high reflectance for both opaque and semi-transparent RCMs. For a semi-transparent RCM, a low value of the solar transmittance is preferred. The desired infrared property is a high emittance for an opaque RCM. For a semi-transparent RCM, a high infrared transmittance is desired, and the emittance should be greater than zero

  16. Radiant heating of petroleum reservoirs; Aquecimento radiante de reservatorios petroliferos

    Sidrim, Fernando A.C.

    1990-12-31

    This work presents a proposal of a simplified model for the enhanced oil recovery process through radiant heating of oil reservoirs. The resulting continuity, energy and motion equations were solved analytically for the prediction of the increase in well flow rates. The heat loss to adjacent formations and the necessary for the establishment of the temperature profile,which are transient terms of energy equation, have been neglected. Also, no temperature gradient in the axial direction has been modelled as a cylindrical wave propagating in a loss medium. It is concluded that: the inclusion of a radial conduction term in the energy equation led to higher flow rates than the ones predicted by the literature existing solution; if the absorption coefficient is too large, it is profitable to dry the reservoir around the well bore; the transient terms in the energy equation are significant for extended periods of well production. 47 refs., 18 figs., 4 tabs.

  17. Operative temperature drifts and occupant satisfaction with thermal environment in three office buildings using radiant heating/ cooling system

    Kolarik, Jakub; Toftum, Jørn; Olesen, Bjarne W.

    2015-01-01

    , Madrid, Spain (16000 m2), TiFS, Padua, Italy (2200 m2). Continuous measurements of operative temperature were conducted at four workplaces in each building for one year. Occupants’ satisfaction was assessed by internet based questionnaire. Results showed that mostly exceeded limits were those for 4-hour...

  18. Radiant Floor Cooling Systems

    Olesen, Bjarne W.

    2008-01-01

    In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

  19. Energy Efficient Mobile Operating Systems

    Muhammad Waseem

    2013-01-01

    Energy is an important resource in mobile computers now days. It is important to manage energy in efficient manner so that energy consumption will be reduced. Developers of operating system decided to increase the battery life time of mobile phones at operating system level. So, design of energy efficient mobile operating system is the best way to reduce the energy consumption in mobile devices. In this paper, currently used energy efficient mobile operating system is discussed and compared. ...

  20. The effects of mixing air distribution and heat load arrangement on the performance of ceiling radiant panels under cooling mode of operation

    Mustakallio, Panu; Kosonen, Risto; Melikov, Arsen Krikor

    2016-01-01

    arrangement and air distribution generated in a room by linear slot diffuser, radial multi-nozzle diffuser and radial swirl induction unit on the cooling power of radiant panels was compared. The impact on the thermal environment was also studied. Measurements were carried out without and with supply air...

  1. Clouds and the Earth's Radiant Energy System (CERES) algorithm theoretical basis document. volume 2; Geolocation, calibration, and ERBE-like analyses (subsystems 1-3)

    Wielicki, B. A. (Principal Investigator); Barkstrom, B. R. (Principal Investigator); Charlock, T. P.; Baum, B. A.; Green, R. N.; Minnis, P.; Smith, G. L.; Coakley, J. A.; Randall, D. R.; Lee, R. B., III

    1995-01-01

    The theoretical bases for the Release 1 algorithms that will be used to process satellite data for investigation of the Clouds and Earth's Radiant Energy System (CERES) are described. The architecture for software implementation of the methodologies is outlined. Volume 2 details the techniques used to geolocate and calibrate the CERES scanning radiometer measurements of shortwave and longwave radiance to invert the radiances to top-of-the-atmosphere (TOA) and surface fluxes following the Earth Radiation Budget Experiment (ERBE) approach, and to average the fluxes over various time and spatial scales to produce an ERBE-like product. Spacecraft ephemeris and sensor telemetry are used with calibration coefficients to produce a chronologically ordered data product called bidirectional scan (BDS) radiances. A spatially organized instrument Earth scan product is developed for the cloud-processing subsystem. The ERBE-like inversion subsystem converts BDS radiances to unfiltered instantaneous TOA and surface fluxes. The TOA fluxes are determined by using established ERBE techniques. Hourly TOA fluxes are computed from the instantaneous values by using ERBE methods. Hourly surface fluxes are estimated from TOA fluxes by using simple parameterizations based on recent research. The averaging process produces daily, monthly-hourly, and monthly means of TOA and surface fluxes at various scales. This product provides a continuation of the ERBE record.

  2. Dynamic heat transfer modeling and parametric study of thermoelectric radiant cooling and heating panel system

    Luo, Yongqiang; Zhang, Ling; Liu, Zhongbing; Wang, Yingzi; Wu, Jing; Wang, Xiliang

    2016-01-01

    Highlights: • Dynamic model of thermoelectric radiant panel system is established. • The internal parameters of thermoelectric module are dynamically calculated in simulation. • Both artificial neural networks model and system model are verified through experiment data. • Optimized system structure is obtained through parametric study. - Abstract: Radiant panel system can optimize indoor thermal comfort with lower energy consumption. The thermoelectric radiant panel (TERP) system is a new and effective prototype of radiant system using thermoelectric module (TEM) instead of conventional water pipes, as heat source. The TERP can realize more stable and easier system control as well as lower initial and operative cost. In this study, an improved system dynamic model was established by combining analytical system model and artificial neural networks (ANN) as well as the dynamic calculation functions of internal parameters of TEM. The double integral was used for the calculation of surface average temperature of TERP. The ANN model and system model were in good agreement with experiment data in both cooling and heating mode. In order to optimize the system design structure, parametric study was conducted in terms of the thickness of aluminum panel and insulation, as well as the arrangement of TEMs on the surface of radiant panel. It was found through simulation results that the optimum thickness of aluminum panel and insulation are respectively around 1–2 mm and 40–50 mm. In addition, TEMs should be uniformly installed on the surface of radiant panel and each TEM should stand at the central position of a square-shaped typical region with length around 0.387–0.548 m.

  3. Influence of radiant energy exchange on the determination of convective heat transfer rates to Orbiter leeside surfaces during entry

    Throckmorton, D. A.

    1982-01-01

    Temperatures measured at the aerodynamic surface of the Orbiter's thermal protection system (TPS), and calorimeter measurements, are used to determine heating rates to the TPS surface during atmospheric entry. On the Orbiter leeside, where convective heating rates are low, it is possible that a significant portion of the total energy input may result from solar radiation, and for the wing, cross radiation from the hot (relatively) Orbiter fuselage. In order to account for the potential impact of these sources, values of solar- and cross-radiation heat transfer are computed, based upon vehicle trajectory and attitude information and measured surface temperatures. Leeside heat-transfer data from the STS-2 mission are presented, and the significance of solar radiation and fuselage-to-wing cross-radiation contributions to total energy input to Orbiter leeside surfaces is assessed.

  4. Radiant absorption characteristics of corrugated curved tubes

    Đorđević Milan Lj.

    2017-01-01

    Full Text Available The utilization of modern paraboloidal concentrators for conversion of solar radiation into heat energy requires the development and implementation of compact and efficient heat absorbers. Accurate estimation of geometry influence on absorption characteristics of receiver tubes is an important step in this process. This paper deals with absorption characteristics of heat absorber made of spirally coiled tubes with transverse circular corrugations. Detailed 3-D surface-to-surface Hemicube method was applied to compare radiation performances of corrugated and smooth curved tubes. The numerical results were obtained by varying the tube curvature ratio and incident radiant heat flux intensity. The details of absorption efficiency of corrugated tubes and the effect of curvature on absorption properties for both corrugated and smooth tubes were presented. The results may have significance to further analysis of highly efficient heat absorbers exposed to concentrated radiant heating. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 42006

  5. Radiant exchange in partially specular architectural environments

    Beamer, C. Walter; Muehleisen, Ralph T.

    2003-10-01

    The radiant exchange method, also known as radiosity, was originally developed for thermal radiative heat transfer applications. Later it was used to model architectural lighting systems, and more recently it has been extended to model acoustic systems. While there are subtle differences in these applications, the basic method is based on solving a system of energy balance equations, and it is best applied to spaces with mainly diffuse reflecting surfaces. The obvious drawback to this method is that it is based around the assumption that all surfaces in the system are diffuse reflectors. Because almost all architectural systems have at least some partially specular reflecting surfaces in the system it is important to extend the radiant exchange method to deal with this type of surface reflection. [Work supported by NSF.

  6. Thermal model of attic systems with radiant barriers

    Wilkes, K.E.

    1991-07-01

    This report summarizes the first phase of a project to model the thermal performance of radiant barriers. The objective of this phase of the project was to develop a refined model for the thermal performance of residential house attics, with and without radiant barriers, and to verify the model by comparing its predictions against selected existing experimental thermal performance data. Models for the thermal performance of attics with and without radiant barriers have been developed and implemented on an IBM PC/AT computer. The validity of the models has been tested by comparing their predictions with ceiling heat fluxes measured in a number of laboratory and field experiments on attics with and without radiant barriers. Cumulative heat flows predicted by the models were usually within about 5 to 10 percent of measured values. In future phases of the project, the models for attic/radiant barrier performance will be coupled with a whole-house model and further comparisons with experimental data will be made. Following this, the models will be utilized to provide an initial assessment of the energy savings potential of radiant barriers in various configurations and under various climatic conditions. 38 refs., 14 figs., 22 tabs.

  7. State Energy Program Operations Manual

    Office of Building Technology, State and Community Programs

    1999-03-17

    The State Energy Program Operations Manual is a reference tool for the states and the program officials at the U.S. Department of Energy's Office of Building Technology, State and Community Programs and Regional Support Offices as well as State Energy Offices. The Manual contains information needed to apply for and administer the State Energy Program, including program history, application rules and requirements, and program administration and monitoring requirements.

  8. Energy efficiency of electrical infrared heating elements

    Brown, K.J.; Farrelly, R.; O’Shaughnessy, S.M.; Robinson, A.J.

    2016-01-01

    Highlights: • Characterization of the radiant energy efficiency of infrared heating elements. • Performed for a commercially available ceramic heater element for two cases. • Total radiant power and net radiant efficiency is computed. • Radiant efficiencies are strongly dependant on the input power to the element. • In-plane efficiencies depend on the distance from the heater. - Abstract: A measurement system has been designed to characterize the radiant energy efficiency of infrared heating elements. The system also allows for measurement of the radiant heat flux distribution emitted from radiant heater assemblies. To facilitate these, a 6-axis robotic arm is fitted with a Schmidt–Boelter radiant heat flux gauge. A LabVIEW interface operates the robot and positions the sensor in the desired location and subsequently acquires the desired radiant heat flux measurement. To illustrate the functionality of the measurement system and methodology, radiant heat flux distributions and efficiency calculations are performed for a commercially available ceramic heater element for two cases. In the first, a spherical surface is traced around the entire heater assembly and the total radiant power and net radiant efficiency is computed. In the second, 50 cm × 50 cm vertical planes are traced parallel to the front face of the heater assembly at distances between 10 cm and 50 cm and the in-plane power and efficiencies are computed. The results indicate that the radiant efficiencies are strongly dependant on the input power to the element and, for the in-plane efficiencies, depend on the distance from the heater.

  9. Simplified Building Thermal Model Used for Optimal Control of Radiant Cooling System

    Lei He

    2016-01-01

    Full Text Available MPC has the ability to optimize the system operation parameters for energy conservation. Recently, it has been used in HVAC systems for saving energy, but there are very few applications in radiant cooling systems. To implement MPC in buildings with radiant terminals, the predictions of cooling load and thermal environment are indispensable. In this paper, a simplified thermal model is proposed for predicting cooling load and thermal environment in buildings with radiant floor. In this thermal model, the black-box model is introduced to derive the incident solar radiation, while the genetic algorithm is utilized to identify the parameters of the thermal model. In order to further validate this simplified thermal model, simulated results from TRNSYS are compared with those from this model and the deviation is evaluated based on coefficient of variation of root mean square (CV. The results show that the simplified model can predict the operative temperature with a CV lower than 1% and predict cooling loads with a CV lower than 10%. For the purpose of supervisory control in HVAC systems, this simplified RC thermal model has an acceptable accuracy and can be used for further MPC in buildings with radiation terminals.

  10. A full-scale experimental set-up for assessing the energy performance of radiant wall and active chilled beam for cooling buildings

    Le Dreau, Jerome; Heiselberg, Per; Jensen, Rasmus Lund

    2015-01-01

    in decreasing the cooling need of the radiant wall compared to the active chilled beam. It has also been observed that the type and repartition of heat load have an influence on the cooling demand. Regarding the comfort level, both terminals met the general requirements, except at high solar heat gains......: overheating has been observed due to the absence of solar shading and the limited cooling capacity of the terminals. No local discomfort has been observed although some segments of the thermal manikin were slightly colder....

  11. Performance evaluation of radiant cooling system application on a university building in Indonesia

    Satrio, Pujo; Sholahudin, S.; Nasruddin

    2017-03-01

    The paper describes a study developed to estimate the energy savings potential of a radiant cooling system installed in an institutional building in Indonesia. The simulations were carried out using IESVE to evaluate thermal performance and energy consumption The building model was calibrated using the measured data for the installed radiant system. Then this calibrated model was used to simulate the energy consumption and temperature distribution to determine the proportional energy savings and occupant comfort under different systems. The result was radiant cooling which integrated with a Dedicated Outside Air System (DOAS) could make 41,84% energy savings compared to the installed cooling system. The Computational Fluid Dynamics (CFD) simulation showed that a radiant system integrated with DOAS provides superior human comfort than a radiant system integrated with Variable Air Volume (VAV). Percentage People Dissatisfied was kept below 10% using the proposed system.

  12. Radiant recuperator modelling and design

    Knežević Suzana D.

    2017-01-01

    Full Text Available Recuperators are frequently used in glass production and metallurgical processes to preheat combustion air by heat exchange with high temperature flue gases. Mass and energy balances of a 15 m high, concurrent radiant recuperator used in a glass fiber production process are given. The balances are used: for validation of a cell modeling method that predicts the performance of different recuperator designs, and for finding a simple solution to improve the existing recuperator. Three possible solutions are analyzed: to use the existing recuperator as a countercurrent one, to add an extra cylinder over the existing construction, and to make a system that consists of a central pipe and two concentric annular ducts. In the latter, two air streams flow in opposite directions, whereas air in the inner annular passage flows concurrently or countercurrently to flue gases. Compared with the concurrent recuperator, the countercurrent has only one drawback: the interface temperature is higher at the bottom. The advantages are: lower interface temperature at the top where the material is under maximal load, higher efficiency, and smaller pressure drop. Both concurrent and countercurrent double pipe-in-pipe systems are only slightly more efficient than pure concurrent and countercurrent recuperators, respectively. Their advantages are smaller interface temperatures whereas the disadvantages are their costs and pressure drops. To implement these solutions, the average velocities should be: for flue gas around 5 m/s, for air in the first passage less than 2 m/s, and for air in the second passage more than 25 m/s. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. EE 33027

  13. Radiant Heating and Cooling Systems. Part one

    Kim, Kwan Woo; Olesen, Bjarne W.

    2015-01-01

    The use of radiant heating systems has several thousand years of history.1,2 The early stage of radiant system application was for heating purposes, where hot air from flue gas (cooking, fires) was circulated under floors or in walls. After the introduction of plastic piping water-based radiant...

  14. Energy efficient heating and ventilation of large halls

    Hojer, Ondrej; Kabele, Karel; Kotrbaty, Miroslav; Sommer, Klaus; Petras, Dusan

    2011-01-01

    This guidebook is focused on modern methods for design, control and operation of energy efficient heating systems in large spaces and industrial halls. The book deals with thermal comfort, light and dark gas radiant heaters, panel radiant heating, floor heating and industrial air heating systems. Various heating systems are illustrated with case studies. Design principles, methods and modeling tools are presented for various systems.

  15. A RADIANT AIR-CONDITIONING SYSTEM USING SOLAR-DRIVEN

    S. A. ABDALLA

    2006-12-01

    Full Text Available Every air-conditioning system needs some fresh air to provide adequate ventilation air required to remove moisture, gases like ammonia and hydrogen sulphide, disease organisms, and heat from occupied spaces. However, natural ventilation is difficult to control because urban areas outside air is often polluted and cannot be supplied to inner spaces before being filtered. Besides the high electrical demand of refrigerant compression units used by most air-conditioning systems, and fans used to transport the cool air through the thermal distribution system draw a significant amount of electrical energy in comparison with electrical energy used by the building thermal conditioning systems. Part of this electricity heats the cooled air; thereby add to the internal thermal cooling peak load. In addition, refrigerant compression has both direct and indirect negative effects on the environment on both local and global scales. In seeking for innovative air-conditioning systems that maintain and improve indoor air quality under potentially more demanding performance criteria without increasing environmental impact, this paper presents radiant air-conditioning system which uses a solar-driven liquid desiccant evaporative cooler. The paper describes the proposed solar-driven liquid desiccant evaporative cooling system and the method used for investigating its performance in providing cold water for a radiant air-conditioning system in Khartoum (Central Sudan. The results of the investigation show that the system can operate in humid as well as dry climates and that employing such a system reduces air-conditioning peak electrical demands as compared to vapour compression systems.

  16. Advanced, Integrated Control for Building Operations to Achieve 40% Energy Saving

    Lu, Yan; Song, Zhen; Loftness, Vivian; Ji, Kun; Zheng, Sam; Lasternas, Bertrand; Marion, Flore; Yuebin, Yu

    2012-10-15

    We developed and demonstrated a software based integrated advanced building control platform called Smart Energy Box (SEB), which can coordinate building subsystem controls, integrate variety of energy optimization algorithms and provide proactive and collaborative energy management and control for building operations using weather and occupancy information. The integrated control system is a low cost solution and also features: Scalable component based architecture allows to build a solution for different building control system configurations with needed components; Open Architecture with a central data repository for data exchange among runtime components; Extendible to accommodate variety of communication protocols. Optimal building control for central loads, distributed loads and onsite energy resource; uses web server as a loosely coupled way to engage both building operators and building occupants in collaboration for energy conservation. Based on the open platform of SEB, we have investigated and evaluated a variety of operation and energy saving control strategies on Carnegie Mellon University Intelligent Work place which is equipped with alternative cooling/heating/ventilation/lighting methods, including radiant mullions, radiant cooling/heating ceiling panels, cool waves, dedicated ventilation unit, motorized window and blinds, and external louvers. Based on the validation results of these control strategies, they were integrated in SEB in a collaborative and dynamic way. This advanced control system was programmed and computer tested with a model of the Intelligent Workplace's northern section (IWn). The advanced control program was then installed in the IWn control system; the performance was measured and compared with that of the state of the art control system to verify the overall energy savings great than 40%. In addition advanced human machine interfaces (HMI's) were developed to communicate both with building

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

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

    2014-01-01

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

  18. Radiant zone heated particulate filter

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  19. Subjective evaluation of different ventilation concepts combined with radiant heating and cooling

    Krajcik, Michal; Tomasi, Roberta; Simone, Angela

    2012-01-01

    Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation and radiant heating/cooling systems. Two test setups simulated a room in a low energy building with a single occupant during winter. The room was equipped either by a ventilation system...... supplying warm air space heating or by a combination of radiant floor heating and mixing ventilation system. Next two test setups simulated an office room with two occupants during summer, ventilated and cooled by a single displacement ventilation system or by a radiant floor cooling combined...

  20. Advanced radiant combustion system. Final report, September 1989--September 1996

    Sullivan, J.D.; Carswell, M.G.; Long, F.S.

    1996-09-01

    Results of the Advanced Radiant Combustion System (ARCS) project are presented in this report. This work was performed by Alzeta Corporation as prime contractor under a contract to the U.S. Department of Energy Office of Industrial Technologies as part of a larger DOE program entitled Research Program for Advanced Combustion Systems. The goals of the Alzeta ARCS project were to (a) Improve the high temperature performance characteristics of porous surface ceramic fiber burners, (b) Develop an Advanced Radiant Combustion System (ARCS) that combines combustion controls with an advanced radiant burner, and (c) Demonstrate the advanced burner and controls in an industrial application. Prior to the start of this project, Alzeta had developed and commercialized a porous surface radiant burner, the Pyrocore{trademark} burner. The product had been commercially available for approximately 5 years and had achieved commercial success in a number of applications ranging from small burners for commercial cooking equipment to large burners for low temperature industrial fluid heating applications. The burner was not recommended for use in applications with process temperatures above 1000{degrees}F, which prevented the burner from being used in intermediate to high temperature processes in the chemical and petroleum refining industries. The interest in increasing the maximum use temperature of the burner was motivated in part by a desire to expand the number of applications that could use the Pyrocore product, but also because many of the fluid sensitive heating applications of interest would benefit from the distributed flux characteristic of porous surface burners. Background information on porous surface radiant burners, and a discussion of advantages that would be provided by an improved product, are presented in Section 2.

  1. An experimental study of thermal comfort at different combinations of air and mean radiant temperature

    Simone, Angela; Olesen, Bjarne W.

    2009-01-01

    It is often discussed if a person prefers a low air temperature (ta) and a high mean radiant temperature (tr), vice-versa or it does not matter as long as the operative temperature is acceptable. One of the hypotheses is that it does not matter for thermal comfort but for perceived air quality......, a lower air temperature is preferred. This paper presents an experimental study with 30 human subjects exposed to three different combinations of air- and mean radiant temperature with an operative temperature around 23 °C. The subjects gave subjective evaluations of thermal comfort and perceived air...... quality during the experiments. The PMV-index gave a good estimation of thermal sensation vote (TSV) when the air and mean radiant temperature were the same. In the environment with different air- and mean radiant temperatures, a thermal comfort evaluation shows an error up to 1 scale unit on the 7-point...

  2. Radiant Heat Transfer in Reusable Surface Insulation

    Hughes, T. A.; Linford, R. M. F.; Chmitt, R. J.; Christensen, H. E.

    1973-01-01

    During radiant testing of mullite panels, temperatures in the insulation and support structure exceeded those predicted on the basis of guarded hot plate thermal conductivity tests. Similar results were obtained during arc tunnel tests of mullite specimens. The differences between effective conductivity and guarded hot plate values suggested that radiant transfer through the mullite was occurring. To study the radiant transport, measurements were made of the infrared transmission through various insulating materials and fibers of interest to the shuttle program, using black body sources over the range of 780 to 2000 K. Experimental data were analyzed and scattering coefficients were derived for a variety of materials, fiber diameters, and source temperature.

  3. Performance analysis on solar-water compound source heat pump for radiant floor heating system

    曲世林; 马飞; 仇安兵

    2009-01-01

    A solar-water compound source heat pump for radiant floor heating (SWHP-RFH) experimental system was introduced and analyzed. The SWHP-RFH system mainly consists of 11.44 m2 vacuum tube solar collector,1 000 L water tank assisted 3 kW electrical heater,a water source heat pump,the radiant floor heating system with cross-linked polyethylene (PE-X) of diameter 20 mm,temperature controller and solar testing system. The SWHP-RFH system was tested from December to February during the heating season in Beijing,China under different operation situations. The test parameters include the outdoor air temperature,solar radiation intensity,indoor air temperature,radiation floor average surface temperature,average surface temperature of the building envelope,the inlet and outlet temperatures of solar collector,the temperature of water tank,the heat medium temperatures of heat pump condenser side and evaporator side,and the power consumption includes the water source heat pump system,the solar source heat pump system,the auxiliary heater and the radiant floor heating systems etc. The experimental results were used to calculate the collector efficiency,heat pump dynamic coefficient of performance (COP),total energy consumption and seasonal heating performance during the heating season. The results indicate that the performance of the compound source heat pump system is better than that of the air source heat pump system. Furthermore,some methods are suggested to improve the thermal performance of each component and the whole SWHP-RFH system.

  4. Operational Energy Strategy: Implementation Plan

    2012-03-01

    U.S. forces to obtain the energy required to perform their missions. To achieve this goal, the Department will identify and remediate energy-related...construction projects related to hydropower and biogas to build local capacity in Afghanistan. Responsibilities. The Joint Staff and Military

  5. Electric radiant heating: A hot item in home comfort

    Lemieux, G. [Britech Corp., Toronto, ON (Canada)

    2003-12-01

    Electric radiant heating as a floor warming system and its growing popularity in home comfort are discussed. Price can be as low as $2.00 per square foot; cost of operation may be as little as 30 cents per square foot per year, depending on time of use and local hydro rates. The use of radiant cable heating is said to have surged in popularity; it provides the same warmth and comfort as more expensive hydronic systems. Radiant cable is simple and inexpensive to install since unlike hydronic systems, it requires no complicated mechanical system with boiler, heat exchanger, valves, pumps and extensive controls. Nevertheless, prospective end users are warned to make sure that the cable is sturdy, tough, has multiple layers of protection with a thick grounding system and conductor core. In addition to heating floors, electric heating cables can also be used for snow and ice control and for melting in driveways and gutters. In these type of installations heavy duty cables are used which are installed under asphalt, concrete or interlocking stones. Thirty watts per square foot per hour is the typical requirement for melting snow and ice. Based on average electricity prices in Ontario, melting snow on an 800 square foot driveway would cost about $2.20 per hour. Assuming five hours for the system to clear the driveway, installing a heating system under the driveway could be an economically viable solution for the home owner, providing freedom from ice, the inconvenience of shovelling snow, and saving time and money.

  6. Operational Energy Base Camp Studies

    2011-08-01

    project for the rehabilitation of an Afghan Ministry of Energy and Water (MEW) biogas plant, which broke ground on 13 December 10. Plant...for public release; distribution is unlimited. Prepared for Headquarters, US Army Corps of Engineers Washington, DC 20314-1000 Under Project ...recommendation or category of recommendations. In this initial stage of work, the Project Delivery Team (PDT) performed a literature review to identify the

  7. Ten questions about radiant heating and cooling systems

    Rhee, Kyu-Nam; Olesen, Bjarne W.; Kim, Kwang Woo

    2017-01-01

    studies on RHC systems in terms of comfort, heat transfer analysis, energy simulation, control strategy, system configurations and so on. Many studies have demonstrated that the RHC system is a good solution to improve indoor environmental quality while reducing building energy consumption for heating......Radiant heating and cooling (RHC) systems are being increasingly applied not only in residential but also in non-residential buildings such as commercial buildings, education facilities, and even large scale buildings such as airport terminals. Furthermore, with the combined ventilation system used...

  8. Operational overhead of moving to higher energies

    Lamont, M

    2011-01-01

    The operational overheads of moving above 3.5 TeV are examined. The costs of performing such a move at the start, or during, the 2011 run are evaluated. The impact of operation with beams above 3.5 TeV on machine protection systems is briefly reviewed, and any potential limitations are enumerated. Finally the possible benefits of increasing the beam energy on the luminosity are discussed.

  9. Airflow and Heat Transfer in the Slot-Vented Room with Radiant Floor Heating Unit

    Xiang-Long Liu

    2012-01-01

    Full Text Available Radiant floor heating has received increasing attention due to its diverse advantages, especially the energy saving as compared to the conventional dwelling heating system. This paper presents a numerical investigation of airflow and heat transfer in the slot-vented room with the radiant floor heating unit. Combination of fluid convection and thermal radiation has been implemented through the thermal boundary conditions. Spatial distributions of indoor air temperature and velocity, as well as the heat transfer rates along the radiant floor and the outer wall, have been presented and analyzed covering the domains from complete natural convection to forced convection dominated flows. The numerical results demonstrate that the levels of average temperature in the room with lateral slot-ventilation are higher than those without slot-ventilation, but lower than those in the room with ceiling slot-ventilation. Overall, the slot-ventilation room with radiant floor heating unit could offer better indoor air quality through increasing the indoor air temperature and fresh air exchanging rate simultaneously. Concerning the airborne pollutant transports and moisture condensations, the performance of radiant floor heating unit will be further optimized in our future researches.

  10. Piezoelectric energy harvesting through shear mode operation

    Malakooti, Mohammad H; Sodano, Henry A

    2015-01-01

    Piezoelectric materials are excellent candidates for use in energy harvesting applications due to their high electromechanical coupling properties that enable them to convert input mechanical energy into useful electric power. The electromechanical coupling coefficient of the piezoelectric material is one of the most significant parameters affecting energy conversion and is dependent on the piezoelectric mode of operation. In most piezoceramics, the d 15 piezoelectric shear coefficient is the highest coefficient compared to the commonly used axial and transverse modes that utilize the d 33 and the d 31 piezoelectric strain coefficients. However, complicated electroding methods and challenges in evaluating the performance of energy harvesting devices operating in the shear mode have slowed research in this area. The shear deformation of a piezoelectric layer can be induced in a vibrating sandwich beam with a piezoelectric core. Here, a model based on Timoshenko beam theory is developed to predict the electric power output from a cantilever piezoelectric sandwich beam under base excitations. It is shown that the energy harvester operating in the shear mode is able to generate ∼50% more power compared to the transverse mode for a numerical case study. Reduced models of both shear and transverse energy harvesters are obtained to determine the optimal load resistance in the system and perform an efficiency comparison between two models with fixed and adaptive resistances. (paper)

  11. Numerical Model and Experimental Analysis of the Thermal Behavior of Electric Radiant Heating Panels

    Giovanni Ferrarini

    2018-01-01

    Full Text Available Electric radiant heating panels are frequently selected during the design phase of residential and industrial heating systems, especially for retrofit of existing buildings, as an alternative to other common heating systems, such as radiators or air conditioners. The possibility of saving living and working space and the ease of installation are the main advantages of electric radiant solutions. This paper investigates the thermal performance of a typical electric radiant panel. A climatic room was equipped with temperature sensors and heat flow meters to perform a steady state experimental analysis. For the dynamic behavior, a mathematical model was created and compared to a thermographic measurement procedure. The results showed for the steady state an efficiency of energy transformation close to one, while in a transient thermal regime the time constant to reach the steady state condition was slightly faster than the typical ones of hydronic systems.

  12. Smart Operations in Distributed Energy Resources System

    Wei, Li; Jie, Shu; Zhang-XianYong; Qing, Zhou

    Smart grid capabilities are being proposed to help solve the challenges concerning system operations due to that the trade-offs between energy and environmental needs will be constantly negotiated while a reliable supply of electricity needs even greater assurance in case of that threats of disruption have risen. This paper mainly explores models for distributed energy resources system (DG, storage, and load),and also reviews the evolving nature of electricity markets to deal with this complexity and a change of emphasis on signals from these markets to affect power system control. Smart grid capabilities will also impact reliable operations, while cyber security issues must be solved as a culture change that influences all system design, implementation, and maintenance. Lastly, the paper explores significant questions for further research and the need for a simulation environment that supports such investigation and informs deployments to mitigate operational issues as they arise.

  13. Operational Experience from Solar Thermal Energy Projects

    Cameron, C. P.

    1984-01-01

    Over the past few years, Sandia National Laboratories were involved in the design, construction, and operation of a number of DOE-sponsored solar thermal energy systems. Among the systems currently in operation are several industrial process heat projects and the Modular Industrial Solar Retrofit qualification test systems, all of which use parabolic troughs, and the Shenandoah Total Energy Project, which uses parabolic dishes. Operational experience has provided insight to both desirable and undesirable features of the designs of these systems. Features of these systems which are also relevant to the design of parabolic concentrator thermal electric systems are discussed. Other design features discussed are system control functions which were found to be especially convenient or effective, such as local concentrator controls, rainwash controls, and system response to changing isolation. Drive systems are also discussed with particular emphasis of the need for reliability and the usefulness of a manual drive capability.

  14. Electric radiant heating : a hot profitable idea

    Lemieux, G. [Britech Corp., Toronto, ON (Canada)

    2006-09-15

    Due to the high cost of heating oil, natural gas and propane, floor mounted radiant heating systems are now proving to be a cost effective method of heating homes. The systems provide evenly distributed heat across the entire floor area. Unlike hydronic floor systems, radiant floor systems require no maintenance, and are easy to control because no mechanical rooms or boilers are required. The system is comprised of a series of resistant heating cables, a thermostat, and a solid state relay. The cables are installed in a poured concrete pad. Separate temperature control devices are used to heat individual areas of floorspace. Building automation systems can also control the heating system by using simple ambient air- and floor-mounted sensors in conjunction with relays to energize the heating cables. The cost of thermostats and heating cables to heat a standard 2000 square foot home are estimated at $9000.00, with an additional 64 hours of installation costs. It was noted that the systems may prove to be less costly in the long-term than hydronic systems, which require additional boilers, pumps and water treatments. Electric radiant heating can be an even more cost-effective application when used with thermal storage heating applications that use lower-cost off-peak electricity to generate and store heat in concrete floor slabs or ceramic bricks contained in insulated cabinets. It was concluded that radiant heating systems are a viable and cost-effective alternative to expensive hydronic systems, which are costly to install and maintain. 4 figs.

  15. Measurement of radiant properties of ceramic foam

    Hoornstra, J.; Turecky, M.; Maatman, D.

    1994-07-01

    An experimental facility is described for the measurement of the normal spectral and total emissivity and transmissivity of semi-transparent materials in the temperature range of 600 C to 1200 C. The set-up was used for the measurement of radiation properties of highly porous ceramic foam which is used in low NO x radiant burners. Emissivity and transmissivity data were measured and are presented for coated and uncoated ceramic foam of different thicknesses. (orig.)

  16. Defense.gov Special Report: Defense Officials Release Operational Energy

    , DOD Operational Energy Strategy DOD's Operational Energy Strategy will guide the Defense Department to operations are among the goals of the Defense Department's operational energy strategy, a senior Pentagon operational energy footprint, experts in solar power, microgrids and "smart" generators recently

  17. The effects of different footprint sizes and cloud algorithms on the top-of-atmosphere radiative flux calculation from the Clouds and Earth's Radiant Energy System (CERES instrument on Suomi National Polar-orbiting Partnership (NPP

    W. Su

    2017-10-01

    Full Text Available Only one Clouds and Earth's Radiant Energy System (CERES instrument is onboard the Suomi National Polar-orbiting Partnership (NPP and it has been placed in cross-track mode since launch; it is thus not possible to construct a set of angular distribution models (ADMs specific for CERES on NPP. Edition 4 Aqua ADMs are used for flux inversions for NPP CERES measurements. However, the footprint size of NPP CERES is greater than that of Aqua CERES, as the altitude of the NPP orbit is higher than that of the Aqua orbit. Furthermore, cloud retrievals from the Visible Infrared Imaging Radiometer Suite (VIIRS and the Moderate Resolution Imaging Spectroradiometer (MODIS, which are the imagers sharing the spacecraft with NPP CERES and Aqua CERES, are also different. To quantify the flux uncertainties due to the footprint size difference between Aqua CERES and NPP CERES, and due to both the footprint size difference and cloud property difference, a simulation is designed using the MODIS pixel-level data, which are convolved with the Aqua CERES and NPP CERES point spread functions (PSFs into their respective footprints. The simulation is designed to isolate the effects of footprint size and cloud property differences on flux uncertainty from calibration and orbital differences between NPP CERES and Aqua CERES. The footprint size difference between Aqua CERES and NPP CERES introduces instantaneous flux uncertainties in monthly gridded NPP CERES measurements of less than 4.0 W m−2 for SW (shortwave and less than 1.0 W m−2 for both daytime and nighttime LW (longwave. The global monthly mean instantaneous SW flux from simulated NPP CERES has a low bias of 0.4 W m−2 when compared to simulated Aqua CERES, and the root-mean-square (RMS error is 2.2 W m−2 between them; the biases of daytime and nighttime LW flux are close to zero with RMS errors of 0.8 and 0.2 W m−2. These uncertainties are within the uncertainties of CERES ADMs

  18. Operational management of offshore energy assets

    Kolios, A. J.; Martinez Luengo, M.

    2016-02-01

    Energy assets and especially those deployed offshore are subject to a variety of harsh operational and environmental conditions which lead to deterioration of their performance and structural capacity over time. The aim of reduction of CAPEX in new installations shifts focus to operational management to monitor and assess performance of critical assets ensuring their fitness for service throughout their service life and also to provide appropriate and effective information towards requalification or other end of life scenarios, optimizing the OPEX. Over the last decades, the offshore oil & gas industry has developed and applied various approaches in operational management of assets through Structural Health and Condition Monitoring (SHM/CM) systems which can be, at a certain level, transferable to offshore renewable installations. This paper aims to highlight the key differences between offshore oil & gas and renewable energy assets from a structural integrity and reliability perspective, provide a comprehensive overview of different approaches that are available and applicable, and distinguish the benefits of such systems in the efficient operation of offshore energy assets.

  19. Electric radiant heating or, why are plumbers getting our work?

    Lemieux, G. [Britech, Toronto, ON (Canada)

    2009-02-15

    Electric radiant heating (ERH) technologies are now being installed in floors as a means of reducing heating costs. The radiant installations have seen a large increase in sales over the last decade, and are now being used in commercial applications. Sales of hydronic ERH systems have increased by 24 per cent over the last year. ERH systems are energy efficient and do not cause drafts. The systems consist of resistant heating cables installed within the floors of a room. The cables are supplied as loose cables and tracks with predetermined spacings or rugged, heavier cable that can be stapled onto wooden subfloors. Program temperature setbacks can be applied on a room-by-room basis. Electric thermal storage systems allow building owners to store heat in the floors and are ideal for use in combination with time-of-use electric metering. Some electric utilities are now promoting the use of electric thermal storage in order to reduce demand during peak times. Thermostats used with the systems should have floor sensors and ambient air sensors to control space heating in conjunction with the floor sensor. It was concluded that electrical contractors who gain knowledge in the application and installation of the systems will tap into a growing revenue stream. 5 figs.

  20. Electric radiant heating or, why are plumbers getting our work?

    Lemieux, G.

    2009-01-01

    Electric radiant heating (ERH) technologies are now being installed in floors as a means of reducing heating costs. The radiant installations have seen a large increase in sales over the last decade, and are now being used in commercial applications. Sales of hydronic ERH systems have increased by 24 per cent over the last year. ERH systems are energy efficient and do not cause drafts. The systems consist of resistant heating cables installed within the floors of a room. The cables are supplied as loose cables and tracks with predetermined spacings or rugged, heavier cable that can be stapled onto wooden subfloors. Program temperature setbacks can be applied on a room-by-room basis. Electric thermal storage systems allow building owners to store heat in the floors and are ideal for use in combination with time-of-use electric metering. Some electric utilities are now promoting the use of electric thermal storage in order to reduce demand during peak times. Thermostats used with the systems should have floor sensors and ambient air sensors to control space heating in conjunction with the floor sensor. It was concluded that electrical contractors who gain knowledge in the application and installation of the systems will tap into a growing revenue stream. 5 figs

  1. Operating Characteristics of the low energy accelerator

    Abd El-Baki, M.M.; Abd El-Rahman, M.M.

    2000-01-01

    The main purpose of this work is to describe the construction and operation of low energy accelerator with energy in the range from (zero to 100 KeV.). This accelerator includes an ion source of the cold cathode penning type (with pierce geometry for ion beam extraction), an accelerating tube (with 8 electrodes) and faraday cup for measuring ion current. A vacuum system which gives vacuum of the order 3.0 x 10 8 torr is used. A palladium tube is used to supply the source with pure hydrogen atoms. It was possible to operate this accelerator with an energy 50 KeV. at minimum hydrogen pressure. 6.3 x 10 6 torr. The total resistance applied between the accelerating electrodes R T = 31.5 M OMEGA. These data includes the influence of the pressure in the accelerating tube, the magnetic field of the ion source, the extraction potential and the accelerating potential on the collector ion current. It was possible to accelerate protons with an energy 50 KeV with current about 100 MU A at pressure 6.3 x 10 6 Torr, the source magnetic field + 1100 gauss (I B = 2A), the current = 0.4 A and the extraction potential = 10 K. V

  2. Use of local convective and radiant cooling at warm environment

    Melikov, Arsen Krikor; Krejcirikova, Barbora; Kaczmarczyk, Jan

    2012-01-01

    The effect of four local cooling devices (convective, radiant and combined) on SBS symptoms reported by 24 subjects at 28 ˚C and 50% RH was studied. The devices studied were: (1) desk cooling fan, (2) personalized ventilation providing clean air, (3) two radiant panels and (4) two radiant panels...... and with radiant panel with attached fans, which also helped people to feel less fatigue. The SBS symptoms increased the most when the cooling fan, generating movement of polluted room air, was used....

  3. Energy flow modeling and optimal operation analysis of the micro energy grid based on energy hub

    Ma, Tengfei; Wu, Junyong; Hao, Liangliang

    2017-01-01

    Highlights: • Design a novel architecture for energy hub integrating power hub, cooling hub and heating hub. • The micro energy grid based on energy hub is introduced and its advantages are discussed. • Propose a generic modeling method for the energy flow of micro energy grid. • Propose an optimal operation model for micro energy grid with considering demand response. • The roles of renewable energy, energy storage devices and demand response are discussed separately. - Abstract: The energy security and environmental problems impel people to explore a more efficient, environment friendly and economical energy utilization pattern. In this paper, the coordinated operation and optimal dispatch strategies for multiple energy system are studied at the whole Micro Energy Grid level. To augment the operation flexibility of energy hub, the innovation sub-energy hub structure including power hub, heating hub and cooling hub is put forward. Basing on it, a generic energy hub architecture integrating renewable energy, combined cooling heating and power, and energy storage devices is developed. Moreover, a generic modeling method for the energy flow of micro energy grid is proposed. To minimize the daily operation cost, a day-ahead dynamic optimal operation model is formulated as a mixed integer linear programming optimization problem with considering the demand response. Case studies are undertaken on a community Micro Energy Grid in four different scenarios on a typical summer day and the roles of renewable energy, energy storage devices and demand response are discussed separately. Numerical simulation results indicate that the proposed energy flow modeling and optimal operation method are universal and effective over the entire energy dispatching horizon.

  4. Study on coal char ignition by radiant heat flux.

    Korotkikh, A. G.; Slyusarskiy, K. V.

    2017-11-01

    The study on coal char ignition by CO2-continuous laser was carried out. The coal char samples of T-grade bituminous coal and 2B-grade lignite were studied via CO2-laser ignition setup. Ignition delay times were determined at ambient condition in heat flux density range 90-200 W/cm2. The average ignition delay time value for lignite samples were 2 times lower while this difference is larger in high heat flux region and lower in low heat flux region. The kinetic constants for overall oxidation reaction were determined using analytic solution of simplified one-dimensional heat transfer equation with radiant heat transfer boundary condition. The activation energy for lignite char was found to be less than it is for bituminous coal char by approximately 20 %.

  5. Surface radiant flux densities inferred from LAC and GAC AVHRR data

    Berger, F.; Klaes, D.

    To infer surface radiant flux densities from current (NOAA-AVHRR, ERS-1/2 ATSR) and future meteorological (Envisat AATSR, MSG, METOP) satellite data, the complex, modular analysis scheme SESAT (Strahlungs- und Energieflüsse aus Satellitendaten) could be developed (Berger, 2001). This scheme allows the determination of cloud types, optical and microphysical cloud properties as well as surface and TOA radiant flux densities. After testing of SESAT in Central Europe and the Baltic Sea catchment (more than 400scenes U including a detailed validation with various surface measurements) it could be applied to a large number of NOAA-16 AVHRR overpasses covering the globe.For the analysis, two different spatial resolutions U local area coverage (LAC) andwere considered. Therefore, all inferred results, like global area coverage (GAC) U cloud cover, cloud properties and radiant properties, could be intercompared. Specific emphasis could be made to the surface radiant flux densities (all radiative balance compoments), where results for different regions, like Southern America, Southern Africa, Northern America, Europe, and Indonesia, will be presented. Applying SESAT, energy flux densities, like latent and sensible heat flux densities could also be determined additionally. A statistical analysis of all results including a detailed discussion for the two spatial resolutions will close this study.

  6. Cutback for grid operators; Netbeheerders energie gekort

    Meulmeester, P. [GEN Nederland, Rotterdam (Netherlands); De Laat, J. [NRE Netwerk, Eindhoven (Netherlands)

    2006-02-24

    The Netherlands Competition Authority (NMa), in which the Office of Energy Regulation (DTe) is included plan to decrease the capital cost compensation (or weighted average cost of capital or WACC) for grid operators. In this article it is explained how the compensation is calculated, why this measure will be taken and what the effects of this cutback are. [Dutch] De NMa/DTe wil de vermogenskostenvergoeding voor netbeheerders naar beneden bijstellen. In dit stuk worden de effecten van deze verlaging besproken door eerst uitleg te geven over maatstafconcurrentie als reguleringssystematiek en de rol van de vermogenskostenvergoeding in deze systematiek. Hierna wordt verklaard hoe de vermogenskostenvergoeding wordt berekend en waarom deze wordt veranderd. Tot slot bekijken we het effect van deze verlaging.

  7. Radiant non-catalytic recuperative reformer

    Khinkis, Mark J.; Kozlov, Aleksandr P.

    2017-10-31

    A radiant, non-catalytic recuperative reformer has a flue gas flow path for conducting hot exhaust gas from a thermal process and a reforming mixture flow path for conducting a reforming mixture. At least a portion of the reforming mixture flow path is positioned adjacent to the flue gas flow path to permit heat transfer from the hot exhaust gas to the reforming mixture. The reforming mixture flow path contains substantially no material commonly used as a catalyst for reforming hydrocarbon fuel (e.g., nickel oxide, platinum group elements or rhenium), but instead the reforming mixture is reformed into a higher calorific fuel via reactions due to the heat transfer and residence time. In a preferred embodiment, a portion of the reforming mixture flow path is positioned outside of flue gas flow path for a relatively large residence time.

  8. Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

    Rabus, H.; Klein, R.; Scholze, F.; Thornagel, R.; Ulm, G.

    2002-01-01

    The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to the ablation of the graphite coating from the copper cavity body. In the case of the new gold-coated cavity absorber, the calculated and measured values of the radiant power agreed in all experiments within the combined relative uncertainties of typically 2.5 x 10 -3 (k = 1). (author)

  9. Achieving Energy Efficient Ship Operations Under Third Party Management

    Taudal Poulsen, René; Sornn-Friese, Henrik

    2015-01-01

    Profitable energy saving measures are often not fully implemented in shipping, causing energy efficiency gaps. The paper identifies energy efficiency gaps in ship operations, and explores their causes. Lack of information on energy efficiency, lack of energy training at sea and onshore and lack...... of time to produce and provide reliable energy efficiency information cause energy efficiency gaps. The paper brings together the energy efficiency and ship management literatures, demonstrating how ship management models influence energy efficiency in ship operations. Achieving energy efficiency in ship...

  10. Numerical analysis of diffuse ceiling ventilation and its integration with a radiant ceiling system

    Zhang, Chen; Heiselberg, Per Kvols; Chen, Qingyan

    2017-01-01

    A novel system combining diffuse ceiling ventilation and radiant ceiling was proposed recently, with the aim of providing energy efficient and comfort environment to office buildings. Designing of such a system is challenging because of complex interactions between the two subsystems and a large ......-uniformity air distribution and further led to the draught problem in the occupied zone. This system was recommended to apply in the small offices instead of large, open spaces....

  11. Dynamic behavior of radiant cooling system based on capillary tubes in walls made of high performance concrete

    Mikeska, Tomás; Svendsen, Svend

    2015-01-01

    elements made of high performance concrete. The influence of the radiant cooling system on the indoor climate of the test room in terms of the air, surface and operative temperatures and velocities was investigated.The results show that the temperature of the room air can be kept in a comfortable range...... using cooling water for the radiant cooling system with a temperature only about 4K lower than the temperature of the room air. The relatively high speed reaction of the designed system is a result of the slim construction of the sandwich wall elements made of high performance concrete. (C) 2015...... the small amount of fresh air required by standards to provide a healthy indoor environment.This paper reports on experimental analyses evaluating the dynamic behavior of a test room equipped with a radiant cooling system composed of plastic capillary tubes integrated into the inner layer of sandwich wall...

  12. Error analysis of thermocouple measurements in the Radiant Heat Facility

    Nakos, J.T.; Strait, B.G.

    1980-12-01

    The measurement most frequently made in the Radiant Heat Facility is temperature, and the transducer which is used almost exclusively is the thermocouple. Other methods, such as resistance thermometers and thermistors, are used but very rarely. Since a majority of the information gathered at Radiant Heat is from thermocouples, a reasonable measure of the quality of the measurements made at the facility is the accuracy of the thermocouple temperature data

  13. Development of Optimal Stressor Scenarios for New Operational Energy Systems

    2017-12-01

    OPTIMAL STRESSOR SCENARIOS FOR NEW OPERATIONAL ENERGY SYSTEMS by Geoffrey E. Fastabend December 2017 Thesis Advisor: Alejandro S... ENERGY SYSTEMS 5. FUNDING NUMBERS 6. AUTHOR(S) Geoffrey E. Fastabend 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School...developed and tested simulation model for operational energy related systems in order to develop better stressor scenarios for acceptance testing

  14. Radiant heat testing of the H1224A shipping/storage container

    Harding, D.C.; Bobbe, J.G.; Stenberg, D.R.; Arviso, M.

    1994-05-01

    H1224A weapons containers have been used for years by the Departments of Energy and Defense to transport and store W78 warhead midsections. Although designed to protect the midsections only from low-energy impacts, a recent transportation risk assessment effort has identified a need to evaluate the container`s ability to protect weapons in more severe accident environments. Four radiant heat tests were performed: two each on an H1224A container (with a Mk12a Mod 6c mass mock-up midsection inside) and two on a low-cost simulated H1224A container (with a hollow Mk12 aeroshell midsections inside). For each unit tested, temperatures were recorded at numerous points throughout the container and midsection during a 4-hour 121{degrees}C (250{degrees}F) and 30-minute 1010{degrees}C (1850{degrees}F) radiant environment. Measured peak temperatures experienced by the inner walls of the midsections as a result of exposure to the high-temperature radiant environment ranged from 650{degrees} C to 980{degrees} C (1200{degrees} F to 1800{degrees}F) for the H1224A container and 770 {degrees} to 990 {degrees}C (1420{degrees} F to 1810{degrees}F) for the simulated container. The majority of both containers were completely destroyed during the high-temperature test. Temperature profiles will be used to benchmark analytical models and predict warhead midsection temperatures over a wide range of the thermal accident conditions.

  15. Analysis of excimer laser radiant exposure effect toward corneal ablation volume at LASIK procedure

    Adiati, Rima Fitria; Rini Rizki, Artha Bona; Kusumawardhani, Apriani; Setijono, Heru; Rahmadiansah, Andi

    2016-11-01

    LASIK (Laser Asissted In Situ Interlamelar Keratomilieusis) is a technique for correcting refractive disorders of the eye such as myopia and astigmatism using an excimer laser. This procedure use photoablation technique to decompose corneal tissues. Although preferred due to its efficiency, permanency, and accuracy, the inappropriate amount radiant exposure often cause side effects like under-over correction, irregular astigmatism and problems on surrounding tissues. In this study, the radiant exposure effect toward corneal ablation volume has been modelled through several processes. Data collecting results is laser data specifications with 193 nm wavelength, beam diameter of 0.065 - 0.65 cm, and fluence of 160 mJ/cm2. For the medical data, the myopia-astigmatism value, cornea size, corneal ablation thickness, and flap data are taken. The first modelling step is determining the laser diameter between 0.065 - 0.65 cm with 0.45 cm increment. The energy, power, and intensity of laser determined from laser beam area. Number of pulse and total energy is calculated before the radiant exposure of laser is obtained. Next is to determine the parameters influence the ablation volume. Regression method used to create the equation, and then the spot size is substituted to the model. The validation used is statistic correlation method to both experimental data and theory. By the model created, it is expected that any potential complications can be prevented during LASIK procedures. The recommendations can give the users clearer picture to determine the appropriate amount of radiant exposure with the corneal ablation volume necessary.

  16. Operations Optimization of Hybrid Energy Systems under Variable Markets

    Chen, Jun; Garcia, Humberto E.

    2016-07-01

    Hybrid energy systems (HES) have been proposed to be an important element to enable increasing penetration of clean energy. This paper investigates the operations flexibility of HES, and develops a methodology for operations optimization to maximize its economic value based on predicted renewable generation and market information. The proposed operations optimizer allows systematic control of energy conversion for maximal economic value, and is illustrated by numerical results.

  17. Towards Perpetual Energy Operation in Wireless Communication Systems

    Benkhelifa, Fatma

    2017-01-01

    energy operation of wireless communication systems, energy harvesting (EH) from the radio frequency (RF) signals is one promising solution to make the wireless communication systems self-sustaining. Since RF signals are known to transmit information

  18. Renewable Energy Operation and Conversion Schemes

    Spagnuolo, Giovanni; Petrone, Giovanni; Araujo, Samuel Vasconcelos

    2010-01-01

    A short summary of some speeches given during Seminar on Renewable Energy system (SERENE) is presented. The contributions have been mainly focused on power electronics for photovoltaic (PV) and sea wave energies, pointing out some aspects related to efficiency, reliability, and grid integration. ...

  19. Lowering operation costs by energy recovery

    Wegener, W; Hausmann, H; Hausmann, K H

    1976-01-01

    Heat recovery and the heat sources available as well as possible applications of the heat recovered are discussed. Groundwater, shower water and waste air are considered as energy sources. Energy recovery by means of finned-tube systems and the heat pump, and economic aspects of the techniques are described.

  20. Operation of buildings: Energy supply and energy conservation measures

    Kraft, H

    1985-01-01

    Energy saving in public administration. A list-like collection of the measures to monitor the consumption, the measures of saving energy at existing buildings, new systems and by new techniques. Examples with figures for the savings achieved in the region of Marburg-Biedenkopf (Hesse). Guidelines are set up which are mainly based on energy saving, heat recovery, use of new technologies and renewable energy sources, fluidized-bed combustion also in smaller plants of ca. 2 MW, waste management separating wastes into burnable/unburnable, information of the public administration and the people and the setting up of energy concepts. (PJH).

  1. Prediction of radiant heat flux from horizontal propane jet fire

    Zhou, Kuibin; Liu, Jiaoyan; Jiang, Juncheng

    2016-01-01

    Highlights: • Line source model for the radiant heat flux from horizontal jet fire is proposed. • A review on the difference between horizontal and vertical jet fires is conducted. • Effects of lift-off distance and flame shape are discussed for the line source model. • Line source model gives encouraging results relative to the validity of model system. - Abstract: Jet fires are often reported to occur in process industry with lots of hazardous heat energy released. A line source model describing the flame emissive power and subsequent heat flux radiated from a horizontal propane jet fire is evaluated through a testing against experimental fire data and comparison against other models. By a review on the jet flame behavior, the correlations of the lift-off distance, flame length and radiative fraction are proposed to close the line source model in theory. It is found that the fuel jet direction holds a considerable effect on the flame behavior by comparison between horizontal and vertical jet fires. Results indicate that the lift-off distance and the flame shape influence the model prediction to some extent. Comparison of model predictions against data collected in the near field and predictions from the point source model and multipoint source model gives encouraging results relative to the validity of model system.

  2. Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

    Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

    1998-01-16

    RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.

  3. Low-energy operators in effective theories

    Felline, C.; Piekarewicz, J.; Mehta, N.P.; Shepard, J.R.

    2003-01-01

    Modern effective-theory techniques are applied to the nuclear many-body problem. A novel approach is proposed for the renormalization of operators in a manner consistent with the construction of the effective potential. To test this approach, a one-dimensional, yet realistic, nucleon-nucleon potential is introduced. An effective potential is then constructed by tuning its parameters to reproduce the exact effective-range expansion and a variety of bare operators are renormalized in a fashion compatible with this construction. Predictions for the expectation values of these effective operators in the ground state reproduce the results of the exact theory with remarkable accuracy (at the 0.5% level). This represents a marked improvement over a widely practiced approach that uses effective interactions but retains bare operators. Further, it is shown that this improvement is more impressive as the operator becomes more sensitive to the short-range structure of the potential. We illustrate the main ideas of this work using the elastic form factor of the deuteron as an example

  4. Energy conservation aircraft design and operational procedures

    Poisson-Quinton, P.

    1978-01-01

    The paper reviews studies associated with improved fuel efficiency. Several aircraft design concepts are described including: (1) increases in aerodynamic efficiency through decreased friction drag, parasitic drag, and drag due to lift, (2) structural efficiency and the implementation of composite materials, (3) active control technology, (4) the optimization of airframe-engine integration, and (5) VTOL and STOL concepts. Consideration is also given to operational procedures associated with flight management, terminal-area operations, and the influence of environmental noise constraints on fuel economy.

  5. Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

    Rabus, H; Scholze, F; Thornagel, R; Ulm, G

    2002-01-01

    The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to th...

  6. Danish wind energy co-operatives

    Tranaes, Flemming

    1993-01-01

    An outline is given of the historical development of Danish wind energy cooperatives. Topics covered include wind turbine owners and their relations with parliament and public authorities, the power station companies and the wind turbine industry. Interest in the environment and support of popular cooperative activities in the local community are essential to success. (UK)

  7. Energy management handbook for building operating engineers student workbook

    1979-09-01

    The handbook provides operating engineers with the basic information needed to implement specific energy conservation opportunities, and additional information is presented relative to the formulation and development of the energy management plan. Chapters are entitled: The Need for Energy Management (International Factors, The US Energy Situation, Energy and the Building Owner); The Fundamentals of Energy Consumption in Buildings (Energy Basics, Heat Basics, Heat Flow and the Building Envelope, Air and Comfort, Factors Affecting Energy Use In Buildings); Principles of Energy Conservation (Building Energy Consumption Characteristics); Planning the Energy Management Program (Obtaining Commitment and Support, Establishing the Energy Use Index, Organizing to Develop the Plan, Developing and Implementing the Plan); Conducting a Survey of Facilities and Operations (The Energy Audit, Preparation of Building and Systems Profile, Measurement and Instrumentation); Guidelines for Energy Conservation (Operator ECO's, Owner ECO'S); Developing the Draft Final Plan (Analyze Survey Findings, Putting the Plan on Paper, Review and Submit); Implementing the Program (Developing the Final Plan, Implementing the Plan, Monitoring and Updating the Program). A glossary is included and specific information on degree days and cooling hours for some selected cities and a computer energy study data for the New York Hilton are included in appendices. (MCW)

  8. Growth and solar energy conversion of Azolla sp., cultivated under four solar irradiance flux density; Crescimento e conversao da energia solar de Azolla sp. cultivada em quatro densidades do fluxo radiante

    Carvalho, E.F. de [Acre Univ., Rio Branco, AC (Brazil); Lopes, N.F. [Vicosa Univ., MG (Brazil). Dept. de Biologia Vegetal

    1994-02-01

    Growth and solar energy conversion were studied in three Azolla species grown under four levels (30, 50, 70 and 100%) of solar radiation incidence under outdoor conditions. Under full sunlight, the specie A. microphylla showed higher crop growth rate, relative growth rate, net assimilation rate and efficiency of solar energy conversion than the other ones. (author). 8 figs., 23 refs.

  9. Magnetic fusion energy. Disaster operation procedures

    1986-06-01

    In a major disaster such as an earthquake, toxic chemical release, or fire, these Disaster Operations Procedures can be used, in combination with good judgment, to minimize the risk of injury to personnel and of property damage in our laboratory, shop, and office areas. These emergency procedures apply to all personnel working within MFE/Zone-11 area including visitors, program contract personnel, and construction contract personnel

  10. Energy Storage Management for Grid Operation Purposes

    Ricardo Santos; Ricardo André; Ricardo Bessa; Clara Gouveia; António Araújo; Filipe Guerra; José Damásio; Guillermo Bravo; Jean Sumaili

    2016-01-01

    The Horizon 2020 Storage ENabled SustaInable energy for BuiLdings and communitiEs (SENSIBLE) project is currently looking at the integration of small-scale storage technologies in buildings and distribution networks. In the demonstration site of the SENSIBLE project, EDP has already installed an experimental storage system supplying a university campus in MV. It was mainly designed to increase service quality to the university by providing backup power in the event of MV grid failure, but it ...

  11. Energy Hub’s Structural and Operational Optimization for Minimal Energy Usage Costs in Energy Systems

    Thanh Tung Ha

    2018-03-01

    Full Text Available The structural and optimal operation of an Energy Hub (EH has a tremendous influence on the hub’s performance and reliability. This paper envisions an innovative methodology that prominently increases the synergy between structural and operational optimization and targets system cost affordability. The generalized energy system structure is presented theoretically with all selective hub sub-modules, including electric heater (EHe and solar sources block sub-modules. To minimize energy usage cost, an energy hub is proposed that consists of 12 kinds of elements (i.e., energy resources, conversion, and storage functions and is modeled mathematically in a General Algebraic Modeling System (GAMS, which indicates the optimal hub structure’s corresponding elements with binary variables (0, 1. Simulation results contrast with 144 various scenarios established in all 144 categories of hub structures, in which for each scenario the corresponding optimal operation cost is previously calculated. These case studies demonstrate the effectiveness of the suggested model and methodology. Finally, avenues for future research are also prospected.

  12. Experimental and Numerical Study of the Radiant Induction-Unit and the Induction Radiant Air-Conditioning System

    Qiang Si

    2016-12-01

    Full Text Available In this paper we proposed the novel air-conditioning system which combined induction ventilation and radiant air-conditioning. The indoor terminal device is the radiant induction-unit (RIDU. The RIDU is the induction unit combined with the pore radiant panel on which the copper pipes with rigid aluminum diffusion fins are installed. The two-stage evaporator chiller with the non-azeotropic mixture refrigerant is utilized in the system to reduce the initial investment in equipment. With the performance test and the steady state heat transfer model based on the theory of radiative heat transfer, the relationship between the induction ratio of the RIDU and the characteristic of the air supply was studied. Based on this, it is verified that the RIDU has a lower dew-point temperature and better anti-condensation performance than a traditional plate-type radiant panel. The characteristics of the radiation and convection heat transfer of the RIDU were studied. The total heat exchange of the RIDU can be 16.5% greater than that of the traditional plate-type radiant terminal.

  13. Energy Fuels Nuclear, Inc. Arizona Strip Operations

    Pool, T.C.

    1993-01-01

    Founded in 1975 by uranium pioneer, Robert W. Adams, Energy Fuels Nuclear, Inc. (EFNI) emerged as the largest US uranium mining company by the mid-1980s. Confronting the challenges of declining uranium market prices and the development of high-grade ore bodies in Australia and Canada, EFNI aggressively pursued exploration and development of breccia-pipe ore bodies in Northwestern Arizona. As a result, EFNI's production for the Arizona Strip of 18.9 million pounds U 3 O 8 over the period 1980 through 1991, maintained the company's status as a leading US uranium producer

  14. Estimating the energy saving potential of telecom operators in China

    Yang, Tian-Jian; Zhang, Yue-Jun; Huang, Jin; Peng, Ruo-Hong

    2013-01-01

    A set of models are employed to estimate the potential of total energy saved of productions and segmented energy saving for telecom operators in China. During the estimation, the total energy saving is divided into that by technology and management, which are derived from technical reform and progress, and management control measures and even marketing respectively, and the estimating methodologies for energy saving potential of each segment are elaborated. Empirical results from China Mobile indicate that, first, the technical advance in communications technology accounts for the largest proportion (70%–80%) of the total energy saved of productions in telecom sector of China. Second, technical reform brings about 20%–30% of the total energy saving. Third, the proportions of energy saving brought by marketing and control measures appear relatively smaller, just less than 3%. Therefore, China's telecom operators should seize the opportunity of the revolution of communications network techniques in recent years to create an advanced network with lower energy consumption

  15. Nuclear energy in the European energy mix operation

    Gueldner, R.

    2009-01-01

    The world nuclear energy is on the upswing. This is shown by lifetime extensions up to 60 years and the construction of new nuclear power plants. Especially, the progressive climate change requires new, definitive, fast and decisive solutions. Europe has to find the right energy mix for the future having the magic triangle of environmental sustainability, security of supply and economic affordability in mind. At the centre of all the efforts made by many countries all over the world, nuclear is one vital key technology to face and combat global warming. Nuclear has a positive eco-balance, nuclear gives security of supply and nuclear power generation is competitive. Beside this the most important fact is and will be the high safety to run a nuclear power plant. The energy mix in the EU of the next decades will be defined today. It is vital to consider every option, which can contribute to a sustainable energy mix. Nuclear alone is not the solution for all problems but there will be no sustainable solution without nuclear. (author)

  16. International solar energy research co-operation

    Lund, P.; Peippo, K.; Konttinen, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    Finland has participated in several IEA activities during 1996-97. HUT coordinates the activities, but practical participation in collaborative actions take place both in industrial companies and research organisations. Neste Ltd has directly participated in several tasks and information of results has been disseminated more widely to Finnish industries and organisations. Co-operation projects covered here are: (1) IEA Photovoltaic Power Systems Task 1 `Information dissemination`, (2) IEA Photovoltaic Power Systems Task 3 `Use of Photovoltaic systems in Stand Alone and Island Applications`, (3) IEA Photovoltaic Power Systems Task 7 `Photovoltaics in built environment`, (4) IEA Solar Heating and Cooling Program Task 16 `Photovoltaics in buildings` and (5) IEA Working Group `Materials in Solar Thermal Collectors`

  17. Photovoltaics as an operating energy system

    Jones, G. J.; Post, H. N.; Thomas, M. G.

    In the short time since the discovery of the modern solar cell in 1954, terrestrial photovoltaic power system technology has matured in all areas, from collector reliability to system and subsystem design and operations. Today's PV systems are finding widespread use in powering loads where conventional sources are either unavailable, unreliable, or too costly. A broad range of applications is possible because of the modularity of the technology---it can be used to power loads ranging from less than a watt to several megawatts. This inherent modularity makes PV an excellent choice to play a major role in rural electrification in the developing world. The future for grid-connected photovoltaic systems is also very promising. Indications are that several of today's technologies, at higher production rates and in megawatt-sized installations, will generate electricity in the vicinity of $0.12/kWh in the near future.

  18. Research on Operation Assessment Method for Energy Meter

    Chen, Xiangqun; Huang, Rui; Shen, Liman; chen, Hao; Xiong, Dezhi; Xiao, Xiangqi; Liu, Mouhai; Xu, Renheng

    2018-03-01

    The existing electric energy meter rotation maintenance strategy regularly checks the electric energy meter and evaluates the state. It only considers the influence of time factors, neglects the influence of other factors, leads to the inaccuracy of the evaluation, and causes the waste of resources. In order to evaluate the running state of the electric energy meter in time, a method of the operation evaluation of the electric energy meter is proposed. The method is based on extracting the existing data acquisition system, marketing business system and metrology production scheduling platform that affect the state of energy meters, and classified into error stability, operational reliability, potential risks and other factors according to the influencing factors, based on the above basic test score, inspecting score, monitoring score, score of family defect detection. Then, according to the evaluation model according to the scoring, we evaluate electric energy meter operating state, and finally put forward the corresponding maintenance strategy of rotation.

  19. A Method of Evaluating Operation of Electric Energy Meter

    Chen, Xiangqun; Li, Tianyang; Cao, Fei; Chu, Pengfei; Zhao, Xinwang; Huang, Rui; Liu, Liping; Zhang, Chenglin

    2018-05-01

    The existing electric energy meter rotation maintenance strategy regularly checks the electric energy meter and evaluates the state. It only considers the influence of time factors, neglects the influence of other factors, leads to the inaccuracy of the evaluation, and causes the waste of resources. In order to evaluate the running state of the electric energy meter in time, a method of the operation evaluation of the electric energy meter is proposed. The method is based on extracting the existing data acquisition system, marketing business system and metrology production scheduling platform that affect the state of energy meters, and classified into error stability, operational reliability, potential risks and other factors according to the influencing factors, based on the above basic test score, inspecting score, monitoring score, score of family defect detection. Then, according to the evaluation model according to the scoring, we evaluate electric energy meter operating state, and finally put forward the corresponding maintenance strategy of rotation.

  20. CW Energy Recovery Operation of XFELs

    Jacek Sekutowicz; S. Bogacz; Dave Douglas; Peter Kneisel; Gwyn P. Wiliams; Massimo Ferrario; Luca Serafini; Ilan Ben-Zvi; James Rose; Triveni Srinivasan-Rao; Patrick Colestock; Wolf-Dietrich Moeller; Bernd Petersen; Dieter Proch; S. Simrock; James B. Rosenzweig

    2003-01-01

    Commissioning of two large coherent light facilities at SLAC and DESY should begin in 2008 and in 2011 respectively. In this paper we look further into the future, hoping to answer, in a very preliminary way, two questions. First: What will the next generation of the XFEL facilities look like ? Believing that super-conducting technology offers several advantages over room-temperature technology, such as high quality beams with highly populated bunches and the possibility of energy recovery or higher overall efficiency, we focus this preliminary study on the superconducting option. From this belief the second question arises: ''What modifications in superconducting technology and in machine design are needed, as compared to the present DESY XFEL, and what kind of R and D program is required over the next few years to arrive at a technically feasible solution with even higher brilliance and increased overall conversion of AC power to photon beam power. In this paper we will very often refer to and profit from the DESY XFEL design, acknowledging its many technically innovative solutions

  1. Radiant heat loss, an unexploited path for heat stress reduction in shaded cattle.

    Berman, A; Horovitz, T

    2012-06-01

    Rbal with increasing roof height and a reduction in rate of decrease with increasing level of indirect radiation. Roof height as an Rbal attenuator declined with increasing indirect radiation level. The latter factor might be reduced by lowering roof surface radiation absorption and through roof heat transfer, as well as by use of shade structure elements to reduce indirect radiation in the shaded area. Radiant heat from the cow body surface may be reduced by lower cow density. Radiant heat attenuation may thus further elevate animal productivity in warm climates, with no associated operation costs. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Application of roof radiant burners in large pusher-type furnaces

    A. Varga

    2009-07-01

    Full Text Available The paper deals with the application of roof flat-flame burners in the pusher-type steel slab reheating furnaces, after furnace reconstruction and replacement of conventional torch burners, with the objective to increase the efficiency of radiative heat transfer from the refractory roof to the charge. Based on observations and on measurements of the construction and process parameters under operating conditions, the advantages and disadvantages of indirectly oriented radiant heat transfer are analysed in relation to the heat transfer in classically fired furnaces.

  3. Sensitivity analysis of the thermal performance of radiant and convective terminals for cooling buildings

    Le Dréau, J.; Heiselberg, P.

    2014-01-01

    Heating and cooling terminals can be classified in two main categories: convective terminals (e.g. active chilled beam, air conditioning) and radiant terminals. The mode of heat transfer of the two emitters is different: the first one is mainly based on convection, whereas the second one is based...... conducted to determine the parameters influencing their thermal performance the most. The air change rate, the outdoor temperature and the air temperature stratification have the largest effect on the cooling need (maintaining a constant operative temperature). For air change rates higher than 0.5 ACH...

  4. The energy-momentum operator in curved space-time

    Brown, M.R.; Ottewill, A.C.

    1983-01-01

    It is argued that the only meaningful geometrical measure of the energy-momentum of states of matter described by a free quantum field theory in a general curved space-time is that provided by a normal ordered energy-momentum operator. The finite expectation values of this operator are contrasted with the conventional renormalized expectation values and it is further argued that the use of renormalization theory is inappropriate in this context. (author)

  5. Operation optimization of a distributed energy system considering energy costs and exergy efficiency

    Di Somma, M.; Yan, B.; Bianco, N.; Graditi, G.; Luh, P.B.; Mongibello, L.; Naso, V.

    2015-01-01

    Highlights: • Operation optimization model of a Distributed Energy System (DES). • Multi-objective strategy to optimize energy cost and exergy efficiency. • Exergy analysis in building energy supply systems. - Abstract: With the growing demand of energy on a worldwide scale, improving the efficiency of energy resource use has become one of the key challenges. Application of exergy principles in the context of building energy supply systems can achieve rational use of energy resources by taking into account the different quality levels of energy resources as well as those of building demands. This paper is on the operation optimization of a Distributed Energy System (DES). The model involves multiple energy devices that convert a set of primary energy carriers with different energy quality levels to meet given time-varying user demands at different energy quality levels. By promoting the usage of low-temperature energy sources to satisfy low-quality thermal energy demands, the waste of high-quality energy resources can be reduced, thereby improving the overall exergy efficiency. To consider the economic factor as well, a multi-objective linear programming problem is formulated. The Pareto frontier, including the best possible trade-offs between the economic and exergetic objectives, is obtained by minimizing a weighted sum of the total energy cost and total primary exergy input using branch-and-cut. The operation strategies of the DES under different weights for the two objectives are discussed. The operators of DESs can choose the operation strategy from the Pareto frontier based on costs, essential in the short run, and sustainability, crucial in the long run. The contribution of each energy device in reducing energy costs and the total exergy input is also analyzed. In addition, results show that the energy cost can be much reduced and the overall exergy efficiency can be significantly improved by the optimized operation of the DES as compared with the

  6. Analysis of Optimal Operation of an Energy Integrated Distillation Plant

    Li, Hong Wen; Hansen, C.A.; Gani, Rafiqul

    2003-01-01

    The efficiency of manufacturing systems can be significantly increased through diligent application of control based on mathematical models thereby enabling more tight integration of decision making with systems operation. In the present paper analysis of optimal operation of an energy integrated...

  7. Energy and Exergy Performance of three FPSO Operational Modes

    Sánchez, Yamid Alberto Carranza; Junior, Silvio de Oliveira; da Silva, Julio Augusto Mendes

    2015-01-01

    by the FPSO operator. Energy and exergy criteria have been applied to evaluate and compare the performance of components and systems of the three operational modes of the FPSO. The processing and utilities plants have been modeled and simulated by using Aspen HYSYS®. Results indicate that higher oil content...

  8. Renormalizing the Kinetic Energy Operator in Elementary Quantum Mechanics

    Coutinho, F. A. B.; Amaku, M.

    2009-01-01

    In this paper, we consider solutions to the three-dimensional Schrodinger equation of the form [psi](r) = u(r)/r, where u(0) [is not equal to] 0. The expectation value of the kinetic energy operator for such wavefunctions diverges. We show that it is possible to introduce a potential energy with an expectation value that also diverges, exactly…

  9. Stochastic optimization of energy hub operation with consideration of thermal energy market and demand response

    Vahid-Pakdel, M.J.; Nojavan, Sayyad; Mohammadi-ivatloo, B.; Zare, Kazem

    2017-01-01

    Highlights: • Studying heating market impact on energy hub operation considering price uncertainty. • Investigating impact of implementation of heat demand response on hub operation. • Presenting stochastic method to consider wind generation and prices uncertainties. - Abstract: Multi carrier energy systems or energy hubs has provided more flexibility for energy management systems. On the other hand, due to mutual impact of different energy carriers in energy hubs, energy management studies become more challengeable. The initial patterns of energy demands from grids point of view can be modified by optimal scheduling of energy hubs. In this work, optimal operation of multi carrier energy system has been studied in the presence of wind farm, electrical and thermal storage systems, electrical and thermal demand response programs, electricity market and thermal energy market. Stochastic programming is implemented for modeling the system uncertainties such as demands, market prices and wind speed. It is shown that adding new source of heat energy for providing demand of consumers with market mechanism changes the optimal operation point of multi carrier energy system. Presented mixed integer linear formulation for the problem has been solved by executing CPLEX solver of GAMS optimization software. Simulation results shows that hub’s operation cost reduces up to 4.8% by enabling the option of using thermal energy market for meeting heat demand.

  10. NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

    Brizendine, Anthony; Byars, Nan; Sleiti, Ahmad; Gehrig, Bruce; Lu, Na

    2012-12-31

    The primary objective of the Net-Zero Energy Building Operator Training Program (NZEBOT) was to develop certificate level training programs for commercial building owners, managers and operators, principally in the areas of energy / sustainability management. The expected outcome of the project was a multi-faceted mechanism for developing the skill-based competency of building operators, owners, architects/engineers, construction professionals, tenants, brokers and other interested groups in energy efficient building technologies and best practices. The training program draws heavily on DOE supported and developed materials available in the existing literature, as well as existing, modified, and newly developed curricula from the Department of Engineering Technology & Construction Management (ETCM) at the University of North Carolina at Charlotte (UNC-Charlotte). The project goal is to develop a certificate level training curriculum for commercial energy and sustainability managers and building operators that: 1) Increases the skill-based competency of building professionals in energy efficient building technologies and best practices, and 2) Increases the workforce pool of expertise in energy management and conservation techniques. The curriculum developed in this project can subsequently be used to establish a sustainable energy training program that can contribute to the creation of new “green” job opportunities in North Carolina and throughout the Southeast region, and workforce training that leads to overall reductions in commercial building energy consumption. Three energy training / education programs were developed to achieve the stated goal, namely: 1. Building Energy/Sustainability Management (BESM) Certificate Program for Building Managers and Operators (40 hours); 2. Energy Efficient Building Technologies (EEBT) Certificate Program (16 hours); and 3. Energy Efficent Buildings (EEB) Seminar (4 hours). Training Program 1 incorporates the following

  11. Wind Energy: Forecasting Challenges for its Operational Management

    Pinson, Pierre

    2013-01-01

    with the generation of forecasts tailored to the various operational decision problems involved. Indeed, while wind energy may be seen as an environmentally friendly source of energy, full benefits from its usage can only be obtained if one is able to accommodate its variability and limited predictability. Based...... on a short presentation of its physical basics, the importance of considering wind power generation as a stochastic process is motivated. After describing representative operational decision-making problems for both market participants and system operators, it is underlined that forecasts should be issued...

  12. Sustained operation of sensor nodes with energy harvesters and supercapacitors

    Renner, Bernd-Christian

    2013-06-01

    Sensor nodes powered by energy harvesters and supercapacitors open the door to unlimited and uninterrupted operation. This dissertation closes the persistent gap of system integration w.r.t. holistic online energy assessment, develops a new concept for harvest forecasting while assessing the behavior and quality of known approaches, and proposes a novel load adaptation scheme to achieve sustained and uniform sensor node operation with low complexity and computational overhead. For this purpose, a prototype of an energy harvester with a supercapacitor for off-the-shelf sensor nodes is developed and used for practical evaluation.

  13. Operation of multiple superconducting energy doubler magnets in series

    Kalbfleisch, G.; Limon, P.J.; Rode, C.

    1977-01-01

    In order to understand the operational characteristics of the Energy Doubler, a series of experiments were begun which were designed to be a practical test of running superconducting accelerator magnets in series. Two separate tests in which two Energy Doubler dipoles were powered in series are described. Of particular interest are the static losses of the cryostats and the behavior of the coils and cryostats during quenches. The results of the tests show that Energy Doubler magnets can be safely operated near their short sample limit, and that the various safety devices used are adequate to protect the coils and the cryostats from damage

  14. Energy management in mobile devices with the cinder operating system

    Roy, Arjun

    2011-01-01

    We argue that controlling energy allocation is an increasingly useful and important feature for operating systems, especially on mobile devices. We present two new low-level abstractions in the Cinder operating system, reserves and taps, which store and distribute energy for application use. We identify three key properties of control - isolation, delegation, and subdivision - and show how using these abstractions can achieve them. We also show how the architecture of the HiStar information-flow control kernel lends itself well to energy control. We prototype and evaluate Cinder on a popular smartphone, the Android G1. Copyright © 2011 ACM.

  15. Promoting regional energy co-operation in South Asia

    Srivastava, Leena; Misra, Neha

    2007-01-01

    Energy is a key ingredient of the socio-economic development of any region. South Asia is not only one of the fastest growing regions in the world; it is also one of the poorest, which thus puts energy at the very heart of the development process in the region. This paper looks at the challenges faced by the South Asia sub-region for economic co-operation (SASEC) comprised of Bangladesh, Bhutan, India and Nepal, and also at the role of greater regional energy co-operation therein. The region is characterized by pressures of growing economies and increasing population. While the per capita energy consumption is one of the lowest in the world, energy intensity continues to be very high. A large portion of the population lacks access to modern sources of energy and depends on traditional sources that are not only inefficient but also have severe health and environmental problems associated with them. Increasing oil import dependency and huge investment needs for energy market development pose a further challenge. The region has a good resource potential and tremendous scope for energy co-operation, which can play a key role in addressing many of these energy security concerns and in putting it on the path of sustainable development. It is ironic that the record in the area has been so limited and that too in the most basic form of co-operation, i.e. bilateral arrangements between countries. This paper puts forth a multi-pronged strategy for sub-regional energy co-operation encompassing softer options aimed at confidence building to more substantial and larger scale co-operation efforts. Delays in decision making to ensure stronger and mutually beneficial co-operation efforts are associated with high costs not only to the energy sector but also for the entire development agenda. With the precarious energy situation in the region and unprecedented increases in international oil prices seen in recent times, it is high time for policy makers, financing institutions, NGOs

  16. Improved production operating efficiencies through automation: Wascana Energy`s SCADA system implementation in southeast Saskatchewan

    Knudsen, R; Foord, T; Bartle, A

    1996-12-31

    Supervisory control and data acquisition (SCADA) systems covering Wascana Energy`s whole southeast Saskatchewan operating area were implemented in 1994-95. The benefits of this automation were described. Operations practices were reviewed and a brief description of the system was provided. Main features of the system described included data storage/retrieval, data display, alarm group organization, alarm call out monitoring, dynagraph display, and the Microsoft SQL server computer. Automation was found to significantly change the operator`s traditional role and altered operation practices in general. SCADA systems were found to improve operating efficiencies and production performance significantly, when properly implemented and utilized. 6 refs., 3 figs.

  17. Upcrowding energy co-operatives - Evaluating the potential of crowdfunding for business model innovation of energy co-operatives.

    Dilger, Mathias Georg; Jovanović, Tanja; Voigt, Kai-Ingo

    2017-08-01

    Practice and theory have proven the relevance of energy co-operatives for civic participation in the energy turnaround. However, due to a still low awareness and changing regulation, there seems an unexploited potential of utilizing the legal form 'co-operative' in this context. The aim of this study is therefore to investigate the crowdfunding implementation in the business model of energy co-operatives in order to cope with the mentioned challenges. Based on a theoretical framework, we derive a Business Model Innovation (BMI) through crowdfunding including synergies and differences. A qualitative study design, particularly a multiple-case study of energy co-operatives, was chosen to prove the BMI and to reveal barriers. The results show that although most co-operatives are not familiar with crowdfunding, there is strong potential in opening up predominantly local structures to a broader group of members. Building on this, equity-based crowdfunding is revealed to be suitable for energy co-operatives as BMI and to accompany other challenges in the same way. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Radiant smiles everywhere - before the Chernobyl accident

    Anon.

    1986-01-01

    The business reports presented by the Federal German electric utilities for 1985 are almost all simply brillant. Electricity consumption has been going up, some of the utilities even can boast about rates kept constant over the year. But before the printed business reports could be presented to the meetings of shareholders, a nasty cloud threw a dark shadow over all the brilliant results. The Chernobyl accident made some of the hymns over the nuclear electricity increases and nuclear power in general sound rather queer. Could we do without this energy source. Substituting nuclear power would yearly require: 28 million t of oil, or 41 million t of hard coal, or 142 million t of browncoal, or 38 thousand million cubic metres of natural gas. Extrapolating current conditions and assuming best achievements, renewable energy sources might be able to meet 6 p.c. of the primary energy demands by the year 2000. (orig./HP) [de

  19. Guide to Operating and Maintaining EnergySmart Schools

    None

    2010-01-01

    Through a commitment to high performance, school districts are discovering that smart energy choices can create lasting benefits for students, communities, and the environment. For example, an energy efficient school district with 4,000 students can save as much as $160,000 a year in energy costs. Over 10 years, those savings can reach $1.6 million, translating into the ability to hire more teachers, purchase more textbooks and computers, or invest in additional high performance facilities. Beyond these bottomline benefits, schools can better foster student health, decrease absenteeism, and serve as centers of community life. The U.S. Department of Energy's EnergySmart Schools Program promotes a 30 percent improvement in existing school energy use. It also encourages the building of new schools that exceed code (ASHRAE 90.11999) by 50 percent or more. The program provides resources like this Guide to Operating and Maintaining EnergySmart Schools to assist school decisionmakers in planning, financing, operating, and maintaining energy efficient, high performance schools. It also offers education and training for building industry professionals. Operations and maintenance refer to all scheduled and unscheduled actions for preventing equipment failure or decline with the goal of increasing efficiency, reliability, and safety. A preventative maintenance program is the organized and planned performance of maintenance activities in order to prevent system or production problems or failures from occurring. In contrast, deferred maintenance or reactive maintenance (also called diagnostic or corrective maintenance) is conducted to address an existing problem. This guide is a primary resource for developing and implementing a districtor schoolwide operations and maintenance (O&M) program that focuses on energy efficiency. The EnergySmart Schools Solutions companion CD contains additional supporting information for design, renovation, and retrofit projects. The objective

  20. Operation and maintenance strategies for wave energy converters

    Ambühl, Simon; Marquis, Laurent; Kofoed, Jens Peter

    2015-01-01

    costs including costs due to lost electricity production are minimized. The risk-based approach is compared with an approach where only boats are used and another approach where the target is to minimize the downtime of the device. This article presents a dynamic approach for total operation......Inspection and maintenance costs are a significant contributor to the cost of energy for wave energy converters. There are different operation and maintenance strategies for wave energy converters. Maintenance can be performed after failure (corrective) or before a breakdown (preventive) occurs....... Furthermore, a helicopter and boats can be used to transport equipment and personnel to the device, or the whole device can be towed to a harbour for operation and maintenance actions. This article describes, among others, a risk-based inspection and maintenance planning approach where the overall repair...

  1. Numerical simulation of energy efficiency measures: control and operational strategies

    Ardehali, M. M.

    2006-01-01

    The inherent limitation in performance of building envelop components and heating ventilating and air conditioning (HVAC) equipment necessitates the examination of operational strategies for improvement in energy-efficient operation of buildings. Due to the ease of installation and increasing availability of electronic controllers, operational strategies that could be programmed are of particular interest. The Iowa Energy Center in the US has taken the initiative to conduct the necessary assessment of current HVAC technology and the commonly-used operational strategies for commercial and industrial buildings, as applied to the midwestern part of the country, with weather and energy cost data for Des Moines, Iowa. The first part of this study focused on the energy consumption and cost effectiveness of HVAC systems. The objectives of the second part is concerned with examination of various operational strategies, namely, night purge (NP), fan optimum start and stop (OSS), condenser water reset (CWR), and chilled water reset (CHWR) applied to order and newer-type commercial office buildings. The indoor air quality requirement are met and the latest applicable energy rates from local utility companies are used. The results show that, in general, NP is not an effective strategy in buildings with low thermal mass storage, OSS reduced fan energy, and CWR and CHWR could be effective and require chillers with multi-stage unloading characteristics. The most operationally efficient strategies are the combination of OSS, CWR, and CHWR for the older-type building, and OSS for the newer-type building. Economically, the most effective is the OSS strategy for the older-type building and the CHWR strategy for the newer-type building.(Author)

  2. Flexible operation of thermal plants with integrated energy storage technologies

    Koytsoumpa, Efthymia Ioanna; Bergins, Christian; Kakaras, Emmanouil

    2017-08-01

    The energy system in the EU requires today as well as towards 2030 to 2050 significant amounts of thermal power plants in combination with the continuously increasing share of Renewables Energy Sources (RES) to assure the grid stability and to secure electricity supply as well as to provide heat. The operation of the conventional fleet should be harmonised with the fluctuating renewable energy sources and their intermittent electricity production. Flexible thermal plants should be able to reach their lowest minimum load capabilities while keeping the efficiency drop moderate as well as to increase their ramp up and down rates. A novel approach for integrating energy storage as an evolutionary measure to overcome many of the challenges, which arise from increasing RES and balancing with thermal power is presented. Energy storage technologies such as Power to Fuel, Liquid Air Energy Storage and Batteries are investigated in conjunction with flexible power plants.

  3. Analysis of the results of the energy market operation

    Popovska, V.; Diankov, M.

    2006-01-01

    The paper focuses on the results of the market operation. It includes: analysis of the active market participants and steps to be undertaken in respect of access to the grid and registration on the market, as well as a comparative analysis of the trade at regulated and freely negotiated prices. This report analyses the imbalances of the consumers of energy, generators, including generators operating with one unit. Information about the special role of the public supplier as a main provider of balancing energy, market interruption in case of emergency situation and force major events, circumstances for the parties and contractual relationship is also included. (authors)

  4. Nuclear energy in the operation of the spanish electric system

    Atienza, L.

    2008-01-01

    Nuclear energy plays a basic role in electricity production in Spain. Its high availability rate, the predictability of its fuel recharges, its high operational reliability, its geographical location, the stability of its costs, with its fuel having low weight in the cost structure, the security of supply that the possibility of storing its fuel on-site in the power plant gives and the absence of CO 2 emissions are some of the advantages nuclear energy presents. Its stiffness for demand variations, its sudden disconnections, which are infrequent but with high impact on System Operation, the social perception and nuclear waste management must also be weighted up. (Author)

  5. Residual energy applications program test and operations report

    Zander, F.H.

    1980-10-01

    Objective of REAP in the recovery of waste heat at US gaseous diffusion plants by 1984. This report contains policy, objective, and guideline suggestions for utilizing the proposed Energy applied Systems Test (EAST) Facility and for managing EAST operations; preliminary design information on facility support equipment and physical plant; and estimates of initial construction costs and staffing requirements for a two-bay, three-shift operation

  6. Assuring nuclear energy's future through international co-operation

    Upson, P.

    1999-01-01

    It is invited lecture as the introduction to the sixt international meeting entitled Nuclear Energy in Central Europe. Good commercial operation, public information and education are needed to win the confidence of the public, and to attract young people to take over the industry's founding generation. Stimulating international co-operation and transfer of best practices can assure this happens across the whole of the Europian nuclear industry

  7. Load calculations of radiant cooling systems for sizing the plant

    Bourdakis, Eleftherios; Kazanci, Ongun Berk; Olesen, Bjarne W.

    2015-01-01

    The aim of this study was, by using a building simulation software, to prove that a radiant cooling system should not be sized based on the maximum cooling load but at a lower value. For that reason six radiant cooling models were simulated with two control principles using 100%, 70% and 50......% of the maximum cooling load. It was concluded that all tested systems were able to provide an acceptable thermal environment even when the 50% of the maximum cooling load was used. From all the simulated systems the one that performed the best under both control principles was the ESCS ceiling system. Finally...... it was proved that ventilation systems should be sized based on the maximum cooling load....

  8. Cooling load calculation by the radiant time series method - effect of solar radiation models

    Costa, Alexandre M.S. [Universidade Estadual de Maringa (UEM), PR (Brazil)], E-mail: amscosta@uem.br

    2010-07-01

    In this work was analyzed numerically the effect of three different models for solar radiation on the cooling load calculated by the radiant time series' method. The solar radiation models implemented were clear sky, isotropic sky and anisotropic sky. The radiant time series' method (RTS) was proposed by ASHRAE (2001) for replacing the classical methods of cooling load calculation, such as TETD/TA. The method is based on computing the effect of space thermal energy storage on the instantaneous cooling load. The computing is carried out by splitting the heat gain components in convective and radiant parts. Following the radiant part is transformed using time series, which coefficients are a function of the construction type and heat gain (solar or non-solar). The transformed result is added to the convective part, giving the instantaneous cooling load. The method was applied for investigate the influence for an example room. The location used was - 23 degree S and 51 degree W and the day was 21 of January, a typical summer day in the southern hemisphere. The room was composed of two vertical walls with windows exposed to outdoors with azimuth angles equals to west and east directions. The output of the different models of solar radiation for the two walls in terms of direct and diffuse components as well heat gains were investigated. It was verified that the clear sky exhibited the less conservative (higher values) for the direct component of solar radiation, with the opposite trend for the diffuse component. For the heat gain, the clear sky gives the higher values, three times higher for the peek hours than the other models. Both isotropic and anisotropic models predicted similar magnitude for the heat gain. The same behavior was also verified for the cooling load. The effect of room thermal inertia was decreasing the cooling load during the peak hours. On the other hand the higher thermal inertia values are the greater for the non peak hours. The effect

  9. Operational efficiency of forest energy supply chains in different operational environments

    Roeser, D

    2012-06-15

    Ambitious international efforts to combat climate change have lead to a large interest about the use of forest biomass for energy in many countries. In order to meet the expected growing demand in the future, it will be necessary to improve operational efficiency of existing forest energy supply chains and support the establishment of efficient supply chains in new operational environments. The thesis applied a three-dimensional approach which examines forest energy supply chains from a technical, social and economic viewpoint. Four case studies in different operational environments have been carried out to investigate the applicability of the three dimensional approach to improve operational efficiency. The technical dimension was investigated in Paper 1 and 2. In Paper 1, the effects of climatic conditions, covering of piles, and partial debarking on drying of roundwood were studied in four experimental trials located in Scotland, Finland and Italy. In Paper 2, the chipping of forest biomass was studied in two different operational environments. The investigation of the social dimension in Paper 3 provides insights into the setup of two different supply chains through business process mapping and simulation. Finally, in paper 4, which investigated the economic dimension, an analysis of the effect of the operational environment on technology selection and design of supply chains, is presented. The thesis demonstrates that the chosen approach was practical to investigate the complex relationships between the chosen technologies and different supply chain actors and stakeholders thereby contributing to maintain or improve operational efficiency of forest energy supply chains. Due to its applicability in different operational environments, the approach is also suitable in a more global context. Furthermore, it captures the effect of different aspects and characteristics of the various operational environments on the setup and organization of supply chains. This will

  10. Photosynthetic utilization of radiant energy by CAM Dendrobium flowers

    Khoo, G.H.; Hew, C.S.; He, J.

    1997-01-01

    14 CO 2 fixation was observed in orchid Dendrobium flowers; its rate decreased with the flower development. Chlorophyll (Chl) fluorescence in different developmental stages of flowers was compared to other green plant parts (leaf, inflorescence stalk, and fruit capsule). The photochemical efficiency of photosystem 2 (PS2) (Fv/Fm) of a leaf was 14-21 % higher than that of a mature flower perianth (sepal, petal, and labellum) which had a much lower total Chl content and Chl a/b ratio. A higher quantum yield of PS2 (ΦPS2) than in the mature flowers was observed in all green parts. Flower sepals had higher Chl content, Chl a/b ratio, and Fv/Fm values than the petal and labellum. During flower development the Chl content, Chl a/b ratio, Fv/Fm, and qN decreased while ΦPS2 and qP remained constant. An exposure of developing flowers to irradiances above 50 µmol m -2 s -1 resulted in a very drastic drop of ΦPS2 and qP, and a coherent increase of qN as compared to other green plant organs. A low saturation irradiance (PFD of 100 µmol m -2 s -1 ) and the increase in qN in the flower indicate that irradiation stress may occur since there is no further protection when the flower is exposed to irradiances above 100 µmol m -2 s -1 . A low Chl/carotenoid ratio in mature flower perianth as a consequence of Chl content reduction in the course of flower development suggests a relief of irradiation stress via this mean. (author)

  11. Optimal Operation of Energy Storage in Power Transmission and Distribution

    Akhavan Hejazi, Seyed Hossein

    In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty in system operation. In this regard, we formulate a stochastic programming framework to choose optimal energy and reserve bids for the storage units that takes into account the fluctuating nature of the market prices due to the randomness in the renewable power generation availability. At distribution level, we develop a comprehensive data set to model various stochastic factors on power distribution networks, with focus on networks that have high penetration of electric vehicle charging load and distributed renewable generation. Furthermore, we develop a data-driven stochastic model for energy storage operation at distribution level, where the distribution of nodal voltage and line power flow are modelled as stochastic functions of the energy storage unit's charge and discharge schedules. In particular, we develop new closed-form stochastic models for such key operational parameters in the system. Our approach is analytical and allows formulating tractable optimization problems. Yet, it does not involve any restricting assumption on the distribution of random parameters, hence, it results in accurate modeling of uncertainties. By considering the specific characteristics of random variables, such as their statistical dependencies and often irregularly-shaped probability distributions, we propose a non-parametric chance-constrained optimization approach to operate and plan energy storage units in power distribution girds. In the proposed stochastic optimization, we consider

  12. The energy management manual for arena and rink operators

    Raymer, M. [Saskatchewan Parks and Recreation Assoc., Regina, SK (Canada); White, T. [Office of Energy Conservation, Regina, SK (Canada); Kozoriz, D.F. [SaskPower, Regina, SK (Canada); Norman, D. [SaskPower, Saskatoon, SK (Canada)

    2006-08-15

    In an era when energy costs often rise faster than the community tax base, energy conservation plays a key role in ensuring that skating arenas are able to continue operating. This manual on energy management for arena and rink operators includes current technologies and practices that reduce operating costs. It is meant to help in the training and education of all facility operators. Since fossil fuels are the main source of electrical generation in Saskatchewan, reducing energy consumption directly reduces greenhouse gas emissions to the environment. This manual included a brief introduction to energy calculations for operators of rinks and arenas. The calculations can be performed for the heat loss that occurs in winter and the amount of heat input needed to maintain temperatures. It was recommended that the more difficult calculation of estimating the amount of cooling required for ice making should be done by qualified consultants. The 10 sections of the manual addressed the issues of: (1) electrical and natural gas rates, (2) meters and electrical inventory, (3) making a financial analysis, (4) the building envelope, (5) heating and ventilation, (6) refrigeration, (7) lighting, (8) heating effects of electrical equipment, (9) operation and maintenance, and, (10) project planning. The manual also presented methods to improve the power factor by adding relatively inexpensive components, such as capacitors, to lower electricity bills by as much as 20 per cent. A review of geo-exchange systems for rinks and arenas was included along with heat recovery from refrigeration systems and financial assistance for commercial, institutional and municipal buildings. refs., tabs., figs.

  13. Development and operation of the JAERI superconducting energy recovery linacs

    Minehara, Eisuke J.

    2006-02-01

    The Japan Atomic Energy Research Institute free-electron laser (JAERI FEL) group at Tokai, Ibaraki, Japan has successfully developed one of the most advanced and newest accelerator technologies named "superconducting energy recovery linacs (ERLs)" and some applications in near future using the ERLs. In the text, the current operation and high power JAERI ERL-FEL 10 kW upgrading program, ERL-light source design studies, prevention of the stainless-steel cold-worked stress-corrosion cracking failures and decommissioning of nuclear power plants in nuclear energy industries were reported and discussed briefly as a typical application of the ERL-FEL.

  14. Renormalizing the kinetic energy operator in elementary quantum mechanics

    Coutinho, F A B [Faculdade de Medicina, Universidade de Sao Paulo e LIM 01-HCFMUSP, 05405-000 Sao Paulo (Brazil); Amaku, M [Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, 05508-970 Sao Paulo (Brazil)], E-mail: coutinho@dim.fm.usp.br

    2009-09-15

    In this paper, we consider solutions to the three-dimensional Schroedinger equation of the form {psi}(r) = u(r)/r, where u(0) {ne} 0. The expectation value of the kinetic energy operator for such wavefunctions diverges. We show that it is possible to introduce a potential energy with an expectation value that also diverges, exactly cancelling the kinetic energy divergence. This renormalization procedure produces a self-adjoint Hamiltonian. We solve some problems with this new Hamiltonian to illustrate its usefulness.

  15. A new method for energy accounting in interconnected operations

    Navid, Taghizadegan; Navid, Taghizadegan; Naser, Tabatabaei; Ahmad Reza, Zentabchi; Majid, Mollazadeh

    2005-01-01

    Full text : The measurement of electrical energy supplied to customers or purchased from and delivered to interconnected power systems is of paramount importance in power system operations. Accurate measurement of energy delivered to customers or received from and delivered to other systems is necessary to ensure that billing is correct. energy transferred between systems also must be properly measured and accounted for to ensure that agreed-upon schedules are being met and that each system meets its obligation to match generation with load on a moment-to-moment basis

  16. Renormalizing the kinetic energy operator in elementary quantum mechanics

    Coutinho, F A B; Amaku, M

    2009-01-01

    In this paper, we consider solutions to the three-dimensional Schroedinger equation of the form ψ(r) = u(r)/r, where u(0) ≠ 0. The expectation value of the kinetic energy operator for such wavefunctions diverges. We show that it is possible to introduce a potential energy with an expectation value that also diverges, exactly cancelling the kinetic energy divergence. This renormalization procedure produces a self-adjoint Hamiltonian. We solve some problems with this new Hamiltonian to illustrate its usefulness.

  17. Comparison of operation optimization methods in energy system modelling

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    2013-01-01

    In areas with large shares of Combined Heat and Power (CHP) production, significant introduction of intermittent renewable power production may lead to an increased number of operational constraints. As the operation pattern of each utility plant is determined by optimization of economics......, possibilities for decoupling production constraints may be valuable. Introduction of heat pumps in the district heating network may pose this ability. In order to evaluate if the introduction of heat pumps is economically viable, we develop calculation methods for the operation patterns of each of the used...... energy technologies. In the paper, three frequently used operation optimization methods are examined with respect to their impact on operation management of the combined technologies. One of the investigated approaches utilises linear programming for optimisation, one uses linear programming with binary...

  18. Technical challenges to energy systems' operation and markets

    Soerensen, P.; Meibom, P.; Gehrke, O. [Risoe National Lab. (Denmark); Oestergaard, J. [Technical Univ. of Denmark (Denmark)

    2006-11-15

    A future energy system that includes a high proportion of renewable energy will be expected to meet the same requirements for security of supply and economic efficiency as the energy systems of today, while delivering better environmental performance, especially with regard to CO{sub 2} emissions. Security of supply refers to the long-term reliability of fuel supply; especially in power systems, it also covers short-term requirements for system stability and adequacy. Economic efficiency is concerned with getting the best from the significant amounts of money, human capital and natural resources involved in an energy system. Integral to economic efficiency in energy systems is the presence of well-functioning markets for energy services. The variability and reduced predictability of a number of renewable energy sources, notably wind power, create specific challenges for future energy systems compared to those of today. Power transmission will also become an issue, as the areas with good potential for wind power and wave energy are often located some distance from the centres of power consumption. This chapter describes the challenges involved, and possible solutions to these, with a focus on power systems. The chapter is divided into two sections reflecting the fact that some challenges relate to managing the power system in its normal operation mode, whereas others are specific to fault conditions. (au)

  19. Radiant heat exchange measurements for Tore Supra

    Chatain, D.; Disdier, F.; Gauthier, A.; Raffin, M.; Renaud, M.

    1984-03-01

    In order to minimize the energy consumption of the low temperature cryogenic system connected to the superconducting magnet of TORE-SUPRA, heat exchange from thermal radiation between the vacuum vessels and the thermal shields has been studied. Accordingly large scale cold and hot walls of T.S. have been simulated in a model with reduced dimensions. In this model, the experiment consists in the measurement of the thermal radiated power between two concentric cylindrical surfaces of stainless steel under vacuum conditions. The temperature of the external cylinder was kept constant at 80 K. The internal cylinder was bakeable up to 250 0 C. Various surface treatments were applied on the two cylinders (mechanical polishing and metal deposition of Al, Ag, Ni) [fr

  20. Non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner

    Catapan, R.C.; Costa, M. [Mechanical Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais, 1049-001 Lisbon (Portugal); Oliveira, A.A.M. [Mechanical Engineering Department, Federal University of Santa Catarina, Campus Universitario Professor Joao David Ferreira Lima, 88040-900 Florianopolis, SC (Brazil)

    2011-01-15

    Industrial processes where the heating of large surfaces is required lead to the possibility of using large surface porous radiant burners. This causes additional temperature uniformity problems, since it is increasingly difficult to evenly distribute the reactant mixture over a large burner surface while retaining its stability and keeping low pollutant emissions. In order to allow for larger surface area burners, a non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner using a single large injection hole is proposed and analyzed for a double-layered burner operating in open and closed hot (laboratory-scale furnace, with temperature-controlled, isothermal walls) environments. In both environments, local mean temperatures within the porous medium have been measured. For lower reactant flow rate and ambient temperature the flame shape is conical and anchored at the rim of the injection hole. As the volumetric flow rate or furnace temperature is raised, the flame undergoes a transition to a plane flame stabilized near the external burner surface. However, the stability range envelope remains the same in both regimes. (author)

  1. Energy Storage System Control Algorithm by Operating Target Power to Improve Energy Sustainability of Smart Home

    Byeongkwan Kang

    2018-01-01

    Full Text Available As energy issues are emerging around the world, a variety of smart home technologies aimed at realizing zero energy houses are being introduced. Energy storage system (ESS for smart home energy independence is increasingly gaining interest. However, limitations exist in that most of them are controlled according to time schedules or used in conjunction with photovoltaic (PV generation systems. In consideration of load usage patterns and PV generation of smart home, this study proposes an ESS control algorithm that uses constant energy of energy network while making maximum use of ESS. Constant energy means that the load consumes a certain amount of power under all conditions, which translates to low variability. The proposed algorithm makes a smart home a load of energy network with low uncertainty and complexity. The simulation results show that the optimal ESS operating target power not only makes the smart home use power constantly from the energy network, but also maximizes utilization of the ESS. In addition, since the smart home is a load that uses constant energy, it has the advantage of being able to operate an efficient energy network from the viewpoint of energy providers.

  2. Talisman Energy Inc : corporate social responsibility report 2001 : Sudan operations

    NONE

    2002-07-01

    Talisman Energy Inc. is a large independent Canadian oil and gas producer with operations worldwide, including operations in Sudan, Malaysia, Trinidad and Colombia. This report includes a discussion on seismic exploration in the Acevedo block in Colombia, but most of the report focuses on operations in Sudan because that is the primary concern of many stakeholders, particularly the impact of the long-running civil war in that country and the way in which oil revenues will be used. The report describes Talisman Energy's compliance with the International Code of Ethics for Canadian Business which Talisman adopted in December 1999. The report evaluates Talisman's progress towards achieving objectives in the areas of human rights, community participation, employee rights, ethical business conduct, health, safety and the environment. Talisman will continue to advocate peace and the fair distribution of oil revenues. It was noted that the funding provided by the Sudan oil project consortium Greater Nile Petroleum Operating Company (GNPOC) for community development was increased for 2002. Talisman and GNPOC funding helps in community development initiatives such as the provision of water wells, health clinics and schools in Sudan. PricewaterhouseCoopers (PwC) was asked by Talisman to gather comments on the company's operations in Sudan from a range of stakeholder groups. This report presents audit statements by PwC regarding Talisman's social responsibility. The report also included an independent opinion regarding the challenge of facing ethical dilemmas in business. tabs., figs.

  3. Structural and operational optimisation of distributed energy systems

    Soederman, Jarmo; Pettersson, Frank

    2006-01-01

    A distributed energy system (DES) is a system comprising a set of energy suppliers and consumers, district heating pipelines, heat storage facilities and power transmission lines in a region. Distributed energy production has got an increasingly important role in the energy market. In this paper, a model for structural and operational optimisation of DES is presented. In the model, production and consumption of electrical power and heat, power transmissions, transport of fuels to the production plants, transport of water in the district heating pipelines and storage of heat are taken into account. The problem is formulated as a mixed integer linear programming (MILP) problem where the objective is to minimise the overall cost of DES, i.e., the sum of the running costs for the included operations and the annualised investment costs of the included equipment. An illustrative example is presented for a complex DES situation. The solution gives the DES structure, i.e., which production units, heat transport lines and storages should be built as well as their locations be, together with design parameters for plants and pipelines. The model enables the involved parties-suppliers, consumers, designers and authorities-to form a joint view of different situations as a basis for the decision making. A tool based on the model is built, which can be used in design, in creating guidelines for regional energy policies and for versatile what-if analyses

  4. Methods of performing downhole operations using orbital vibrator energy sources

    Cole, Jack H.; Weinberg, David M.; Wilson, Dennis R.

    2004-02-17

    Methods of performing down hole operations in a wellbore. A vibrational source is positioned within a tubular member such that an annulus is formed between the vibrational source and an interior surface of the tubular member. A fluid medium, such as high bulk modulus drilling mud, is disposed within the annulus. The vibrational source forms a fluid coupling with the tubular member through the fluid medium to transfer vibrational energy to the tubular member. The vibrational energy may be used, for example, to free a stuck tubular, consolidate a cement slurry and/or detect voids within a cement slurry prior to the curing thereof.

  5. Economic Optimal Operation of Community Energy Storage Systems in Competitive Energy Markets

    Arghandeh, Reza; Woyak, Jeremy; Onen, Ahmet; Jung, Jaesung; Broadwater, Robert P.

    2014-01-01

    Distributed, controllable energy storage devices offer several benefits to electric power system operation. Three such benefits include reducing peak load, providing standby power, and enhancing power quality. These benefits, however, are only realized during peak load or during an outage, events that are infrequent. This paper presents a means of realizing additional benefits by taking advantage of the fluctuating costs of energy in competitive energy markets. An algorithm for optimal charge...

  6. Operational Benefits of Meeting California’s Energy Storage Targets

    Josh Eichman, Paul Denholm, Jennie Jorgenson, Udi Helman

    2015-12-01

    In October 2013, the California Public Utilities Commission (CPUC) issued rules for its jurisdictional utilities to procure a minimum of 1,325 megawatts (MW) of energy storage systems by 2020. The goal of this study is to examine the operational value of this storage portfolio in California and the rest of the Western Electricity Coordinating Council (WECC) region. Modeled results show that the storage portfolio, when providing energy and operating reserves, reduces the total WECC-wide production costs by $78 million per year in the 33% scenario. This value increases to $144 million per year in the 40% scenario, primarily because of the increase in off-peak and peak price differences that are due to additional solar generation. These values are equivalent to $59/kW-year for the storage portfolio for the 33% scenario and $109/kW-year for the 40% scenario.

  7. International co-operation in the field of wind energy

    Wolff, J. [VTT Energy, Espoo (Finland)

    1998-10-01

    The use of wind energy is expanding rapidly worldwide. At the end of 1996 over 6000 MW was installed and the annual increase has during the last years exceeded 1000 MW. The development is also reaching more and more countries. In order to maintain technical and commercial development international co-operation is needed to secure cost-effectiveness, reliability and safety of the technology. International recommendations, harmonisation and standardisation is promoted by several international organizations like IEA, IEC and the classification organisations

  8. The Operation Consequence of Nuclear Energy to Environment

    Suhariyono, Gatot; Sutarman

    2003-01-01

    Objective of the paper is to give information the operation consequence of nuclear energy to environment, so that expected as organizer of PLTN can anticipate or depress as minimum as possible radiology impact to the radiation workers and society in general, and also socialization that operation of nuclear energy do not give the negative impact, if conducted its control to environment seriously. Parts of which it is important to know from this paper are : one. Estimate of equivalent dose of collective effective in a normal condition is the operation cycle for nuclear energy at worker and local or regional resident 10, 100 or 10.000 next years. 2. Equivalent dose of global collective effective is for various the radiation sources. 3. Estimate of dose per cap ut annual of nuclear electric power until year 2500. 4. Aspect of non-radiology is to cooler system, usage of farm, dismissal of chemistry, advantage of hot water waste, its effect to fish, benthos, plankton, vegetation, animal and preparation of nuclear emergency

  9. Realizing steady-state tokamak operation for fusion energy

    Luce, T. C.

    2011-01-01

    Continuous operation of a tokamak for fusion energy has clear engineering advantages but requires conditions beyond those sufficient for a burning plasma. The fusion reactions and external sources must support both the pressure and the current equilibrium without inductive current drive, leading to demands on stability, confinement, current drive, and plasma-wall interactions that exceed those for pulsed tokamaks. These conditions have been met individually, and significant progress has been made in the past decade to realize scenarios where the required conditions are obtained simultaneously. Tokamaks are operated routinely without disruptions near pressure limits, as needed for steady-state operation. Fully noninductive sustainment with more than half of the current from intrinsic currents has been obtained for a resistive time with normalized pressure and confinement approaching those needed for steady-state conditions. One remaining challenge is handling the heat and particle fluxes expected in a steady-state tokamak without compromising the core plasma performance.

  10. Radiant science, dark politics: a memoir of the nuclear age

    Kamen, M.D.

    1985-01-01

    The reviewer describes Radiant Science, Dark Politics: A Memoir of the Nuclear Age in contrast to a memoir by James R. Killian, Jr., a contemporary of Kamen. Kamen, co-discoverer of carbon-14 and a valued member of the Berkeley Radiation Laboratory, was fired in 1944 and blackballed as a security risk. Rehabilitated by the end of the war, his continued fight against political injustice through the McCarthy era colors the book and, for the reviewer, makes it self-serving. Kamen's later scientific work reflected his desire to work alone rather than in collaboration

  11. Radiant coolers - Theory, flight histories, design comparisons and future applications

    Donohoe, M. J.; Sherman, A.; Hickman, D. E.

    1975-01-01

    Radiant coolers have been developed for application to the cooling of infrared detectors aboard NASA earth observation systems and as part of the Defense Meteorological Satellite Program. The prime design constraints for these coolers are the location of the cooler aboard the satellite and the satellite orbit. Flight data from several coolers indicates that, in general, design temperatures are achieved. However, potential problems relative to the contamination of cold surfaces are also revealed by the data. A comparison among the various cooler designs and flight performances indicates design improvements that can minimize the contamination problem in the future.

  12. Energy management information systems : achieving improved energy efficiency : a handbook for managers, engineers and operational staff

    Hooke, J.H.; Landry, B.J.; Hart, D. [Natural Resources Canada, Ottawa, ON (Canada). Office of Energy Efficiency

    2004-07-01

    There are many opportunities for industrial and commercial facilities to improve energy efficiency by minimizing waste through process optimization. Large energy users can effectively reduce energy costs, improve profits and reduce greenhouse gas emissions by using computing and control equipment. This book covers all aspects of an Energy Management Information System (EMIS) including metering, data collection, data analysis, reporting and cost benefit analyses. EMIS provides relevant information to businesses that enables them to improve energy performance. EMIS deliverables include early detection of poor performance, support for decision making and effective energy reporting. EMIS also features data storage, calculation of effective targets for energy use and comparative energy consumption. Computer systems can be used to improve business performance in terms of finance, personnel, sales, resource planning, maintenance, process control, design and training. In the 1980s, the Canadian Industry Program for Energy Conservation (CIPEC) developed 2 versions of an energy accounting manual to help industrial, commercial and institutional sectors implement energy-accounting systems. The manual was revised in 1989 and is a useful energy management tool for business and other organizations. The EMIS examples described in this booklet reflect that energy is a variable operating cost, not a fixed overhead charge. 8 tabs., 38 figs.

  13. Towards Perpetual Energy Operation in Wireless Communication Systems

    Benkhelifa, Fatma

    2017-11-01

    Wireless is everywhere. Smartphones, tablets, laptops, implantable medical devices, and many other wireless devices are massively taking part of our everyday activities. On average, an actively digital consumer has three devices. However, most of these wireless devices are small equipped with batteries that are often limited and need to be replaced or recharged. This fact limits the operating lifetime of wireless devices and presents a major challenge in wireless communication. To improve the perpetual energy operation of wireless communication systems, energy harvesting (EH) from the radio frequency (RF) signals is one promising solution to make the wireless communication systems self-sustaining. Since RF signals are known to transmit information, it is interesting to study when RF signals are simultaneously used to transmit information and scavenge energy, namely simultaneous wireless information and power transfer (SWIPT). In this thesis, we specifically aim to study the SWIPT in multiple-input multiple-output (MIMO) relay communication systems and in cognitive radio (CR) networks. First, we study the SWIPT in MIMO relay systems where the relay harvests the energy from the source and uses partially/fully the harvested energy to forward the signal to the destination. For both the amplify-and-forward (AF) and decode-and-forward (DF) relaying protocols, we consider the ideal scheme where both the energy and information transfer to the relay happen simultaneously, and the practical power splitting and time switching schemes. For each scheme, we aim to maximize the achievable end-to-end rate with a certain energy constraint at the relay. Furthermore, we consider the sum rate maximization problem for the multiuser MIMO DF relay broadcasting channels with multiple EH-enabled relays, and an enhanced low complex solution is proposed based on the block diagonalization method. Finally, we study the energy and data performance of the SWIPT in CR network where either the

  14. ANALYSIS OF ENERGY SAVING AND ENERGY EFFICIENCY ISSUES DURING OPERATION OF THE METRO ROLLING STOCK

    A. V. Donchenko

    2016-06-01

    Full Text Available Purpose.Nowadays a problem of significant power consumption of the rolling stock during its operation is a current issue. In connection with staged electricity rates increase further development of the rail electric transport, including metro rolling stock is impossible without a use of modern energy saving solutions and energy-efficient systems. To solve the specified problem it is necessary to carry out analysis of measures and determine prospective directions in energy saving and increase of energy efficiency on the metro rolling stock. Methodology. Using methods of scientific analysis, generalization, comparative analysis, forecasting and using results of experimental studies, the authors determined main ways for reduction of energy consumption during operation of the metro rolling stock. Energy cost analysis for metro rolling stock of the public utility (PU «Kiev Metro» was carried out. A great number of research works of native and foreign authors concerning the above mentioned problem were analyzed. Findings. Principal directions in energy saving and increase of energy efficiency of the metro rolling stock are implementation of recuperation systems, energy storage systems and energy-efficient control systems. It was determined that implementation of recuperation and energy storage systems helps to save a considerable amount of energy, consumed for traction, but it involves substantial investments. It is pointed out that in current complicated conditions of economic development of Ukraine, use of energy-efficient control systems is a perspective direction in energy saving. Main advantage of this direction is the economic effect obtaining without significant investments. Originality. For the first time was performed potential assessment for energy saving as a result of energy-efficient control systems use at type routine rolling stock operation modes on sections «Khreschatik –Teatralnaya – Khreschatik» and «Shulyavskaya

  15. Energy Technology Initiatives - Implementation Through Multilateral Co-operation

    NONE

    2010-07-15

    New technologies will be critical in addressing current global energy challenges such as energy security. More must be done, however, to push forward the development and deployment of the technologies we need today and will need in the future. Government leaders have repeatedly underlined the crucial role of industry and businesses in advancing energy technologies and the importance of strong collaboration among all stakeholders to accelerate technology advances. To attain these goals, increased co-operation between industries, businesses and government energy technology research is indispensable. The public and private sectors must work together, share burdens and resources, while at the same time multiplying results and outcomes. The 42 multilateral technology initiatives (Implementing Agreements) supported by the IEA are a flexible and effective framework for IEA member and non-member countries, businesses, industries, international organisations and non-government organisations to research breakthrough technologies, to fill existing research gaps, to build pilot plants, to carry out deployment or demonstration programmes -- in short to encourage technology-related activities that support energy security, economic growth and environmental protection. This publication highlights the significant accomplishments of the IEA Implementing Agreements.

  16. An experimental study about effect of far infrared radiant ceramics on efficient methane fermentation

    Oda, A.; Yamazaki, M.; Oida, A.

    2003-01-01

    Methane fermentation, well known as one of the methods for organic wastes treatment, has been used as an energy production process in order to produce a gaseous fuel. But methane fermentation has some problems to be solved about gas production rate and volatile solids reduction efficiency. Simple methods to improve these problems are needed. In this study, we focused on far infrared radiant ceramics as a stimulating substance to activate methanogenic bacteria. Firstly, through the experiment of one batch fermentation, it was confirmed that the ceramics in the fermenter caused increase of total gas production. Next, even through the experiment of continuous fermentation, same stimulating effect was confirmed. It was considered that this effect was caused not only by a function of bio-contactor of the ceramics but also by far infrared radiation from ceramics. (author)

  17. Integrating Nuclear Energy to Oilfield Operations - Two Case Studies

    Robertson, Eric P.; Nelson, Lee O.; McKellar, Michael G.; Gandrik, Anastasia M.; Patterson, Mike W.

    2011-01-01

    Fossil fuel resources that require large energy inputs for extraction, such as the Canadian oil sands and the Green River oil shale resource in the western USA, could benefit from the use of nuclear power instead of power generated by natural gas combustion. This paper discusses the technical and economic aspects of integrating nuclear energy with oil sands operations and the development of oil shale resources. A high temperature gas reactor (HTGR) that produces heat in the form of high pressure steam (no electricity production) was selected as the nuclear power source for both fossil fuel resources. Both cases were based on 50,000 bbl/day output. The oil sands case was a steam-assisted, gravity-drainage (SAGD) operation located in the Canadian oil sands belt. The oil shale development was an in-situ oil shale retorting operation located in western Colorado, USA. The technical feasibility of the integrating nuclear power was assessed. The economic feasibility of each case was evaluated using a discounted cash flow, rate of return analysis. Integrating an HTGR to both the SAGD oil sands operation and the oil shale development was found to be technically feasible for both cases. In the oil sands case, integrating an HTGR eliminated natural gas combustion and associated CO2 emissions, although there were still some emissions associated with imported electrical power. In the in situ oil shale case, integrating an HTGR reduced CO2 emissions by 88% and increased natural gas production by 100%. Economic viabilities of both nuclear integrated cases were poorer than the non-nuclear-integrated cases when CO2 emissions were not taxed. However, taxing the CO2 emissions had a significant effect on the economics of the non-nuclear base cases, bringing them in line with the economics of the nuclear-integrated cases. As we move toward limiting CO2 emissions, integrating non-CO2-emitting energy sources to the development of energy-intense fossil fuel resources is becoming

  18. The Dark Energy Survey and Operations: Years 1 to 3

    Diehl, H. T. [Fermilab

    2016-01-01

    The Dark Energy Survey (DES) is an operating optical survey aimed at understanding the accelerating expansion of the universe using four complementary methods: weak gravitational lensing, galaxy cluster counts, baryon acoustic oscillations, and Type Ia supernovae. To perform the 5000 sq-degree wide field and 30 sq-degree supernova surveys, the DES Collaboration built the Dark Energy Camera (DECam), a 3 square-degree, 570-Megapixel CCD camera that was installed at the prime focus of the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO). DES has completed its third observing season out of a nominal five. This paper describes DES “Year 1” (Y1) to “Year 3” (Y3), the strategy, an outline of the survey operations procedures, the efficiency of operations and the causes of lost observing time. It provides details about the quality of the first three season's data, and describes how we are adjusting the survey strategy in the face of the El Niño Southern Oscillation

  19. Nevada Renewable Energy Training Project: Geothermal Power Plant Operators

    Jim, Nichols [Truckee Meadows Community College, Reno, NV (United States)

    2014-04-29

    The purpose of this project was to develop and institute a training program for certified geothermal power plant operators (GPO). An advisory board consisting of subject matter experts from the geothermal energy industry and academia identified the critical skill sets required for this profession. A 34-credit Certificate of Achievement (COA), Geothermal Power Plant Operator, was developed using eight existing courses and developing five new courses. Approval from the Nevada System of Higher Education Board of Regents was obtained. A 2,400 sq. ft. geothermal/fluid mechanics laboratory and a 3,000 sq. ft. outdoor demonstration laboratory were constructed for hands-on training. Students also participated in field trips to geothermal power plants in the region. The majority of students were able to complete the program in 2-3 semesters, depending on their level of math proficiency. Additionally the COA allowed students to continue to an Associate of Applied Science (AAS), Energy Technologies with an emphasis in Geothermal Energy (26 additional credits), if they desired. The COA and AAS are stackable degrees, which provide students with an ongoing career pathway. Articulation agreements with other NSHE institutions provide students with additional opportunities to pursue a Bachelor of Applied Science in Management or Instrumentation. Job placement for COA graduates has been excellent.

  20. Performance Evaluation of Radiator and Radiant Floor Heating Systems for an Office Room Connected to a Ground-Coupled Heat Pump

    Ioan Sarbu

    2016-03-01

    Full Text Available A ground-coupled heat pump (GCHP system used to provide the space heating for an office room is a renewable, high performance technology. This paper discusses vapour compression-based HP systems, briefly describing the thermodynamic cycle calculations, as well as the coefficient of performance (COP and CO2 emissions of a HP with an electro-compressor and compares different heating systems in terms of energy consumption, thermal comfort and environmental impact. It is focused on an experimental study performed to test the energy efficiency of the radiator or radiant floor heating system for an office room connected to a GCHP. The main performance parameters (COP and CO2 emissions are obtained for one month of operation of the GCHP system, and a comparative analysis of these parameters is presented. Additionally, two numerical simulation models of useful thermal energy and the system COP in heating mode are developed using the Transient Systems Simulation (TRNSYS software. Finally, the simulations obtained from TRNSYS software are analysed and compared to the experimental data, showing good agreement and thus validating the simulation models.

  1. Efficient operation of anisotropic synchronous machines for wind energy systems

    Eldeeb, Hisham; Hackl, Christoph M.; Kullick, Julian

    2016-01-01

    This paper presents an analytical solution for the Maximum-Torque-per-Ampere (MTPA) operation of synchronous machines (SM) with anisotropy and magnetic cross-coupling for the application in wind turbine systems and airborne wind energy systems. For a given reference torque, the analytical MTPA solution provides the optimal stator current references which produce the desired torque while minimizing the stator copper losses. From an implementation point of view, the proposed analytical method is appealing in terms of its fast online computation (compared to classical numerical methods) and its efficiency enhancement of the electrical drive system. The efficiency of the analytical MTPA operation, with and without consideration of cross-coupling, is compared to the conventional method with zero direct current. (paper)

  2. Smart Control of Air Climatization System in Function on the Values of Mean Local Radiant Temperature

    Giuseppe Cannistraro

    2015-08-01

    Full Text Available The hygrothermal comfort indoor conditions are defined as: those environmental conditions in which an individual exposed, expresses a state of satisfaction. These conditions cannot always be achieved anywhere in an optimal way and economically; in some cases they can be obtained only in work environments specific areas. This could be explained because of air conditioning systems designing is generally performed both on the basis of the fundamental parameters’ average values, such as temperature, velocity and relative humidity (Ta, va e φa and derived parameters such as operating temperature and mean radiant one (Top eTmr. However, in some specific cases - large open-spaces or in case of radiating surfaces - the descriptors defining indoor comfort conditions, based on average values, do not provide the optimum values required during the air conditioning systems design phase. This is largely due to the variability of real environmental parameters values compared to the average ones taken as input in the calculation. The results obtained in previous scientific papers on the thermal comfort have been the driving element of this work. It offers a simple, original and clever way of thinking about the new domotic systems for air conditioning, based on the “local mean radiant temperature.” This is a very important parameter when one wants to analyze comfort in environments characterized by the presence of radiating surfaces, as will be seen hereinafter. In order to take into account the effects of radiative exchanges in the open-space workplace, where any occupant may find themselves in different temperature and humidity conditions, this paper proposes an action on the domotic climate control, with ducts and vents air distribution placed in different zones. Comparisons were performed between the parameters values representing the punctual thermal comfort, with the Predicted Mean Vote PMV, in an environment marked by radiating surfaces (i

  3. Economic Operation of Supercritical CO2 Refrigeration Energy Storage Technology

    Hay, Ryan

    With increasing penetration of intermittent renewable energy resources, improved methods of energy storage are becoming a crucial stepping stone in the path toward a smarter, greener grid. SuperCritical Technologies is a company based in Bremerton, WA that is developing a storage technology that can operate entirely on waste heat, a resource that is otherwise dispelled into the environment. The following research models this storage technology in several electricity spot markets around the US to determine if it is economically viable. A modification to the storage dispatch scheme is then presented which allows the storage unit to increase its profit in real-time markets by taking advantage of extreme price fluctuations. Next, the technology is modeled in combination with an industrial load profile on two different utility rate schedules to determine potential cost savings. The forecast of facility load has a significant impact on savings from the storage dispatch, so an exploration into this relationship is then presented.

  4. 16 CFR Figure 3 to Subpart A of... - Flooring Radiant Tester Schematic Side Elevation

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Flooring Radiant Tester Schematic Side Elevation 3 Figure 3 to Subpart A of Part 1209 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION.... 1209, Subpt. A, Fig. 3 Figure 3 to Subpart A of Part 1209—Flooring Radiant Tester Schematic Side...

  5. Human response to local convective and radiant cooling in a warm environment

    Melikov, Arsen Krikor; Krejcirikova, Barbora; Kaczmarczyk, Jan

    2013-01-01

    The response of 24 human subjects to local convective cooling, radiant cooling, and combined radiant and convective cooling was studied at 28°C and 50% relative humidity. The local cooling devices used were (1) a tabletop cooling fan, (2) personalized ventilation providing a stream of clean air, (3...

  6. Radiant heat transfer during the natural evaporation from free surfaces exposed to solar radiation; Transferencia de calor radiante durante a evaporacao natural em superficies livres expostas a radiacao solar

    Teixeira, C O.M. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; Hackenberg, C M [Universidade Federal do Rio de Janeiro, RJ (Brazil). Escola de Quimica

    1985-12-31

    In this work a conductive-convective-radiant model which includes phase change behavior, is developed in order to determine the rate of evaporation from free surface exposed to solar radiation and consequently the most important parameters, and their effects, on the design of salt solutions concentrating natural evaporation reservoirs may be analysed. The numerical solutions of the resulting of system of equations are shown to represent very well the experimental results measured on evaporation chambers specially built for daily operations. The thermal effect of spectrally selective surfaces as coating agents for the reservoir is also analysed. (author). 11 refs., 8 figs

  7. Passively-switched energy harvester for increased operational range

    Liu, Tian; Livermore, Carol; Pierre, Ryan St

    2014-01-01

    This paper presents modeling and experimental validation of a new type of vibrational energy harvester that passively switches between two dynamical modes of operation to expand the range of driving frequencies and accelerations over which the harvester effectively extracts power. In both modes, a driving beam with a low resonant frequency couples into ambient vibrations and transfers their energy to a generating beam that has a higher resonant frequency. The generating beam converts the mechanical power into electrical power. In coupled-motion mode, the driving beam bounces off the generating beam. In plucked mode, the driving beam deflects the generating beam until the driving beam passes from above the generating beam to below it or vice versa. Analytical system models are implemented numerically in the time domain for driving frequencies of 3 Hz to 27 Hz and accelerations from 0.1 g to 2.6 g, and both system dynamics and output power are predicted. A corresponding switched-dynamics harvester is tested experimentally, and its voltage, power, and dynamics are recorded. In both models and experiments, coupled-motion harvesting is observed at lower accelerations, whereas plucked harvesting and/or mixed mode harvesting are observed at higher accelerations. As expected, plucked harvesting outputs greater power than coupled-motion harvesting in both simulations and experiments. The predicted (1.8 mW) and measured (1.56 mW) maximum average power levels are similar under measured conditions at 0.5 g. When the system switches to dynamics that are characteristic of higher frequencies, the difference between predicted and measured power levels is more pronounced due to non-ideal mechanical interaction between the beams’ tips. Despite the beams’ non-ideal interactions, switched-dynamics operation increases the harvester’s operating range. (paper)

  8. Projection operator approach to the self-energy

    Capuzzi, F.; Mahaux, C.

    1996-01-01

    Feshbach close-quote s projection operator formalism is extended to the description of the self-energy. This necessitates the introduction of open-quote open-quote extended close-quote close-quote projection operators. They act within an open-quote open-quote extended close-quote close-quote Hilbert space in which the number of nucleons is not fixed. The compact formula derived for the self-energy is formally similar to Feshbach close-quote s original expression of the open-quote open-quote generalized close-quote close-quote optical-model potential. The theory is formulated in the nuclear case, but it also applies to atomic systems. It covers both the open-quote open-quote retarded close-quote close-quote and the open-quote open-quote time-ordered close-quote close-quote Green close-quote s functions, and the open-quote open-quote proper close-quote close-quote and open-quote open-quote improper close-quote close-quote self-energies. It is first worked out in a stationary formalism, in order to better exhibit its analogy with Feshbach close-quote s original theory of the generalized optical-model potential. The main results are then also derived in a time-dependent framework. It is shown that, in finite systems, Dyson close-quote s equation does not uniquely determine the self-energy, in contrast to common assumption. However, the difference between the various possibilities has little practical consequence. We exhibit the relationship between the present approach and a recent open-quote open-quote configuration interaction formulation of the Dyson equation.close-quote close-quote Contact is also established with the open-quote open-quote linked-cluster close-quote close-quote perturbation expansion of the self-energy in powers of the strength of the nucleon endash nucleon interaction. Copyright copyright 1996 Academic Press, Inc

  9. Heuristic Scheduling in Grid Environments: Reducing the Operational Energy Demand

    Bodenstein, Christian

    In a world where more and more businesses seem to trade in an online market, the supply of online services to the ever-growing demand could quickly reach its capacity limits. Online service providers may find themselves maxed out at peak operation levels during high-traffic timeslots but too little demand during low-traffic timeslots, although the latter is becoming less frequent. At this point deciding which user is allocated what level of service becomes essential. The concept of Grid computing could offer a meaningful alternative to conventional super-computing centres. Not only can Grids reach the same computing speeds as some of the fastest supercomputers, but distributed computing harbors a great energy-saving potential. When scheduling projects in such a Grid environment however, simply assigning one process to a system becomes so complex in calculation that schedules are often too late to execute, rendering their optimizations useless. Current schedulers attempt to maximize the utility, given some sort of constraint, often reverting to heuristics. This optimization often comes at the cost of environmental impact, in this case CO 2 emissions. This work proposes an alternate model of energy efficient scheduling while keeping a respectable amount of economic incentives untouched. Using this model, it is possible to reduce the total energy consumed by a Grid environment using 'just-in-time' flowtime management, paired with ranking nodes by efficiency.

  10. Radiant-and-plasma technology for coal processing

    Vladimir Messerle

    2012-12-01

    Full Text Available Radiant-and-plasma technology for coal processing is presented in the article. Thermodynamic computation and experiments on plasma processing of bituminous coal preliminary electron-beam activated were fulfilled in comparison with plasma processing of the coal. Positive influence of the preliminary electron-beam activation of coal on synthesis gas yield was found. Experiments were carried out in the plasma gasifier of 100 kW power. As a result of the measurements of material and heat balance of the process gave the following integral indicators: weight-average temperature of 2200-2300 K, and carbon gasification degree of 82,4-83,2%. Synthesis gas yield at thermochemical preparation of raw coal dust for burning was 24,5% and in the case of electron-beam activation of coal synthesis gas yield reached 36,4%, which is 48% higher.

  11. Results from radiant treatment in no Hodgkin's lymphomas of adults

    Alert, J.; Rodriguez, E.; Mesa, E.; Diaz, C.

    1982-01-01

    From 1973 to 1979, at the Institute of Oncology and Radiobiology, Havana City, 91 adults were irradiated because they underwent no Hodgkin's lymphomas at Stage I (located) and Stage II (regional extension) to whom radiant treatment was the basic therapeutic selection, with single or multiple fields and dose ranging between 3 500 and 4 000 rads-tumor, and some of them at Stage III, where primary treatment was chemotherapy. Present survival for all of them after 3 and 5 years is 55.7% and 54.7%, with 84.4% for patients at Stage I, 55.8% and 52.4% for Stage II and 33.8% for Stage III. Survival was similar for both sexes; in the same way ganglionar processes and those of extraganglionar localization presented no significant survival differences. Only to 7 patients (7.7%) modular forms were diagnosed. (author)

  12. Methods of total spectral radiant flux realization at VNIIOFI

    Ivashin, Evgeniy; Lalek, Jan; Rybczyński, Andrzej; Ogarev, Sergey; Khlevnoy, Boris; Dobroserdov, Dmitry; Sapritsky, Victor

    2018-02-01

    VNIIOFI carries out works on realization of independent methods for realization of the total spectral radiant flux (TSRF) of incoherent optical radiation sources - reference high-temperature blackbodies (BB), halogen lamps, and LED with quasi-Lambert spatial distribution of radiance. The paper describes three schemes for measuring facilities using photometers, spectroradiometers and computer-controlled high class goniometer. The paper describes different approaches for TSRF realization at the VNIIOFI National radiometric standard on the basis of high-temperature BB and LED sources, and gonio-spectroradiometer. Further, they are planned to be compared, and the use of fixed-point cells (in particular, based on the high-temperature δ(MoC)-C metal-carbon eutectic with a phase transition temperature of 2583 °C corresponding to the metrological optical “source-A”) as an option instead of the BB is considered in order to enhance calibration accuracy.

  13. Finite-elements modeling of radiant heat transfers between mobile surfaces; Modelisation par elements finis de transferts radiatifs entre surfaces mobiles

    Daurelle, J V; Cadene, V; Occelli, R [Universite de Provence, 13 - Marseille (France)

    1997-12-31

    In the numerical modeling of thermal industrial problems, radiant heat transfers remain difficult to take into account and require important computer memory and long computing time. These difficulties are enhanced when radiant heat transfers are coupled with finite-elements diffusive heat transfers because finite-elements architecture is complex and requires a lot of memory. In the case of radiant heat transfers along mobile boundaries, the methods must be optimized. The model described in this paper concerns the radiant heat transfers between diffuse grey surfaces. These transfers are coupled with conduction transfers in the limits of the diffusive opaque domain. 2-D and 3-D geometries are analyzed and two configurations of mobile boundaries are considered. In the first configuration, the boundary follows the deformation of the mesh, while in the second, the boundary moves along the fixed mesh. Matter displacement is taken into account in the term of transport of the energy equation, and an appropriate variation of the thermophysical properties of the transition elements between the opaque and transparent media is used. After a description of the introduction of radiative limit conditions in a finite-elements thermal model, the original methods used to optimize calculation time are explained. Two examples of application illustrate the approach used. The first concerns the modeling of radiant heat transfers between fuel rods during a reactor cooling accident, and the second concerns the study of heat transfers inside the air-gap of an electric motor. The method of identification of the mobile surface on the fixed mesh is described. (J.S.) 12 refs.

  14. Finite-elements modeling of radiant heat transfers between mobile surfaces; Modelisation par elements finis de transferts radiatifs entre surfaces mobiles

    Daurelle, J.V.; Cadene, V.; Occelli, R. [Universite de Provence, 13 - Marseille (France)

    1996-12-31

    In the numerical modeling of thermal industrial problems, radiant heat transfers remain difficult to take into account and require important computer memory and long computing time. These difficulties are enhanced when radiant heat transfers are coupled with finite-elements diffusive heat transfers because finite-elements architecture is complex and requires a lot of memory. In the case of radiant heat transfers along mobile boundaries, the methods must be optimized. The model described in this paper concerns the radiant heat transfers between diffuse grey surfaces. These transfers are coupled with conduction transfers in the limits of the diffusive opaque domain. 2-D and 3-D geometries are analyzed and two configurations of mobile boundaries are considered. In the first configuration, the boundary follows the deformation of the mesh, while in the second, the boundary moves along the fixed mesh. Matter displacement is taken into account in the term of transport of the energy equation, and an appropriate variation of the thermophysical properties of the transition elements between the opaque and transparent media is used. After a description of the introduction of radiative limit conditions in a finite-elements thermal model, the original methods used to optimize calculation time are explained. Two examples of application illustrate the approach used. The first concerns the modeling of radiant heat transfers between fuel rods during a reactor cooling accident, and the second concerns the study of heat transfers inside the air-gap of an electric motor. The method of identification of the mobile surface on the fixed mesh is described. (J.S.) 12 refs.

  15. United States Department of Energy, Nevada Operations Office, completion report Operation KLAXON, Fiscal Year 1993

    1994-06-01

    The U.S. Department of Energy, Nevada Operations Office (DOE/NV), Completion Report provides a summary of activities conducted at the Nevada Test Site (NTS) between October 1, 1992, and September 30, 1993, associated with Operation KLAXON. (In the past, each annual Completion Report dealt with a series of underground nuclear detonations; however, because no nuclear tests were conducted during FY 1993, this Report summarizes continuing nonnuclear and nuclear test readiness activities at the NTS sponsored by DOE/NV.) The report serves as a reference for those involved with the planning and execution of Operation KLAXON and also serves as a planning guide for future operations. Information in the report covers the logistics and management of activities. Scientific information and data associated with NTS activities are presented in technical documents published by participating agencies. In September 1992, Congress legislated a nine-month moratorium on the testing of nuclear weapons. The bill also provided for a resumption of testing (with no more than five tests per year, or a total of 15 during the next three years) in July 1993, and mandated an end to nuclear testing, entirely, by 1996. President Bush signed the bill into law in October 1992.

  16. United States Department of Energy, Nevada Operations Office, completion report Operation KLAXON, Fiscal Year 1993

    1994-06-01

    The U.S. Department of Energy, Nevada Operations Office (DOE/NV), Completion Report provides a summary of activities conducted at the Nevada Test Site (NTS) between October 1, 1992, and September 30, 1993, associated with Operation KLAXON. (In the past, each annual Completion Report dealt with a series of underground nuclear detonations; however, because no nuclear tests were conducted during FY 1993, this Report summarizes continuing nonnuclear and nuclear test readiness activities at the NTS sponsored by DOE/NV.) The report serves as a reference for those involved with the planning and execution of Operation KLAXON and also serves as a planning guide for future operations. Information in the report covers the logistics and management of activities. Scientific information and data associated with NTS activities are presented in technical documents published by participating agencies. In September 1992, Congress legislated a nine-month moratorium on the testing of nuclear weapons. The bill also provided for a resumption of testing (with no more than five tests per year, or a total of 15 during the next three years) in July 1993, and mandated an end to nuclear testing, entirely, by 1996. President Bush signed the bill into law in October 1992

  17. Education, energy, toilets, and Earth: The Operators' Manual

    Alley, R. B.; Haines-stiles, G.; Akuginow, E.

    2011-12-01

    Solid science shows the unsustainability of relying on fossil fuels for long-term future energy supply, with increasingly strong evidence that a measured shift to renewable sources will be economically beneficial while improving employment and national security, providing insurance against catastrophes, and more. Yet despite notable advances in renewable energy and related issues, the transition does not appear to be occurring at the economically optimal rate. Analogy may be useful. In biological evolution and business, successful innovation is met by competitors, but also by predators, parasites, and diseases. Trees must handle the competition, but also termites, bark beetles, fungal diseases, strangling vines, and more, while new software meets competitors plus viruses, worms, Trojan horses and other malware. By analogy, the emergence of a "denialsphere" as well as competitors may be a predictable response to the threat posed to business-as-usual by the success of the National Academies and the IPCC in defining the climate-energy problem with the best science, and the growing success of inventors and policy-makers in developing advantageous and increasingly cost-effective solutions. Real questions exist about the best way forward, but the discussion of the important issues is sometimes confused by arguments that are not especially forward-going. Success of beneficial innovations against such problems is not guaranteed but surely has occurred, with transitions as large as that to a low-carbon energy system-we did switch from chamber pots and night-soil haulers to modern sanitation and clean water, for example. Analogy suggests that education and outreach are integral in such a transition, not a job to be completed but a process to be continued. Our attempt to contribute to this large effort, the NSF-supported Earth: The Operators' Manual, emphasizes diverse, interlocking approaches to show the large benefits that are ultimately available, relying on assessed

  18. Safety in design and operation of low energy particle accelerators

    Badawy, I.

    1991-01-01

    This paper studies the safety in design and operation of low energy accelerators which produce beams of accelerated charged particles and radiations. As radiation sources, the accelerators are widely used in scientific research, industry, food and medical applications. The risks to human and environment are considered. The safety in accelerators is discussed-particularly-the shielding against ionizing radiations, overexposure to RF radiation fire hazards and power failures. Also the paper studies the emergency response at incidents. Emergency procedures are recommended for each type of emergency. Reporting to the competent Authority is also recommended to be prepared for each incident. The basic principles of regulatory control, licensing and inspections for accelerator facilities are discussed. The relation with the competent authority is pointed out. 4 fig

  19. Energy-Efficient Train Operation Using Nature-Inspired Algorithms

    Kemal Keskin

    2017-01-01

    Full Text Available A train operation optimization by minimizing its traction energy subject to various constraints is carried out using nature-inspired evolutionary algorithms. The optimization process results in switching points that initiate cruising and coasting phases of the driving. Due to nonlinear optimization formulation of the problem, nature-inspired evolutionary search methods, Genetic Simulated Annealing, Firefly, and Big Bang-Big Crunch algorithms were employed in this study. As a case study a real-like train and test track from a part of Eskisehir light rail network were modeled. Speed limitations, various track alignments, maximum allowable trip time, and changes in train mass were considered, and punctuality was put into objective function as a penalty factor. Results have shown that all three evolutionary methods generated effective and consistent solutions. However, it has also been shown that each one has different accuracy and convergence characteristics.

  20. 78 FR 77447 - California Wind Energy Association, First Solar, Inc. v. California Independent System Operator...

    2013-12-23

    ... Energy Association, First Solar, Inc. v. California Independent System Operator Corporation, Southern...), California Wind Energy Association and First Solar, Inc. (collectively, Complainants) filed a formal complaint against the California Independent System Operator Corporation (CAISO) and Southern California...

  1. Evaluation of Various Retrofitting Concepts of Building Envelope for Offices Equipped with Large Radiant Ceiling Panels by Dynamic Simulations

    Sabina Jordan

    2015-09-01

    Full Text Available In order to achieve significant savings in energy and an improved level of thermal comfort in retrofitted existing buildings, specific retrofitting concepts that combine new technologies and design need to be developed and implemented. Large radiant surfaces systems are now among the most promising future technologies to be used both in retrofitted and in new low-energy buildings. These kinds of systems have been the topic of several studies dealing with thermal comfort and energy utilization, but some specific issues concerning their possible use in various concepts for retrofitting are still poorly understood. In the present paper, some results of dynamic simulations, with the transient system simulation tool (TRNSYS model, of the retrofitted offices equipped with radiant ceiling panels are presented and thoroughly analysed. Based on a precise comparison of the results of these simulations with actual measurements in the offices, certain input data for the model were added, so that the model was consequently validated. The model was then applied to the evaluation of various concepts of building envelopes for office retrofitting. By means of dynamic simulations of indoor environment it was possible to determine the benefits and limitations of individual retrofitting concepts. Some specific parameters, which are relevant to these concepts, were also identified.

  2. Wave Energy, Lever Operated Pivoting Float LOPF Study

    Margheritini, Lucia

    The fully instrumented Resen Waves Lever Operated Pivoting Float LOPF wave energy buoy model has gone through the first stage of testing in regular waves in scale 1:25 of the North Sea wave conditions, in the 3D deep wave basin at the Hydraulic and Coastal Engineering Laboratory of Aalborg...... University in Denmark. The model size was 60cm W x 90cm L x 21cm H. The 60 cm width pointed towards the wave front. The LOPF buoy is characterized by a simple mechanical design with few moving parts and direct electrical output and it is taut moored to the sea bed, so all forces are referenced to the seabed...... for maximum energy output in regular as well as irregular waves. During storms the buoy pivots and streamlines itself to minimize loads on the mooring line. A conservative estimate shows that a full scale system for North Sea conditions has a float size width of 15 m that will, with 60% generator efficiency...

  3. Smart Inverter Control and Operation for Distributed Energy Resources

    Tazay, Ahmad F.

    The motivation of this research is to carry out the control and operation of smart inverters and voltage source converters (VSC) for distributed energy resources (DERs) such as photovoltaic (PV), battery, and plug-in hybrid electric vehicles (PHEV). The main contribution of the research includes solving a couple of issues for smart grids by controlling and implementing multifunctions of VSC and smart inverter as well as improving the operational scheme of the microgrid. The work is mainly focused on controlling and operating of smart inverter since it promises a new technology for the future microgrid. Two major applications of the smart inverter will be investigated in this work based on the connection modes: microgrid at grid-tied mode and autonomous mode. In grid-tied connection, the smart inverter and VSC are used to integrate DER such as Photovoltaic (PV) and battery to provide suitable power to the system by controlling the supplied real and reactive power. The role of a smart inverter at autonomous mode includes supplying a sufficient voltage and frequency, mitigate abnormal condition of the load as well as equally sharing the total load's power. However, the operational control of the microgrid still has a major issue on the operation of the microgrid. The dissertation is divided into two main sections which are: 1. Low-level control of a single smart Inverter. 2. High-level control of the microgrid. The first part investigates a comprehensive research for a smart inverter and VSC technology at the two major connections of the microgrid. This involves controlling and modeling single smart inverter and VSC to solve specific issues of microgrid as well as improve the operation of the system. The research provides developed features for smart inverter comparing with a conventional voltage sourced converter (VSC). The two main connections for a microgrid have been deeply investigated to analyze a better way to develop and improve the operational procedure of

  4. Wave energy, lever operated pivoting float LOPF study

    Margheritini, L.

    2012-11-01

    The fully instrumented Resen Waves Lever Operated Pivoting Float LOPF wave energy buoy model has gone through the first stage of testing in regular waves in scale 1:25 of the North Sea wave conditions, in the 3D deep wave basin at the Hydraulic and Coastal Engineering Laboratory of Aalborg University in Denmark. The model size was 60cm W x 90cm L x 21cm H. The 60 cm width pointed towards the wave front. The LOPF buoy is characterized by a simple mechanical design with few moving parts and direct electrical output and it is taut moored to the sea bed, so all forces are referenced to the seabed for maximum energy output in regular as well as irregular waves. During storms the buoy pivots and streamlines itself to minimize loads on the mooring line. A conservative estimate shows that a full scale system for North Sea conditions has a float size width of 15 m that will, with 60% generator efficiency, produce 610 MWh/y (609.497 kWh/y) with an average power output of 69.6 kW, which requires a generator capacity of 700 kW. It is expected the generator efficiency can be increased to 90% in the future. More specific calculations (from EnergiNet) show that with one generator of 695 kW the expected power production is 585 MWh/y; with a generator of 250 kW and 100 kW, the expected power production is 481 MWh/y and 182 MWh/y respectively. In addition there are several areas for future improvements for increased power production. (Author)

  5. A high gain energy amplifier operated with fast neutrons

    Rubbia, C. [CERN, Geneva (Switzerland)

    1995-10-01

    The basic concept and the main practical considerations of an Energy Amplifier (EA) have been exhaustively described elsewhere. Here the concept of the EA is further explored and additional schemes are described which offer a higher gain, a larger maximum power density and an extended burn-up. All these benefits stem from the use of fast neutrons, instead of thermal or epithermal ones, which was the case in the original study. The higher gain is due both to a more efficient high energy target configuration and to a larger, practical value of the multiplication factor. The higher power density results from the higher permissible neutron flux, which in turn is related to the reduced rate of {sup 233}Pa neutron captures (which, as is well known, suppress the formation of the fissile {sup 233}U fuel) and the much smaller k variations after switch-off due to {sup 233}Pa decays for a given burn-up rate. Finally a longer integrated burn-up is made possible by reduced capture rate by fission fragments of fast neutrons. In practice a 20 MW proton beam (20 mA @ 1 GeV) accelerated by a cyclotron will suffice to operate a compact EA at the level of {approx} 1 GW{sub e}. The integrated fuel burn-up can be extended in excess of 100 GW d/ton, limited by the mechanical survival of the fuel elements. Radio-Toxicity accumulated at the end of the cycle is found to be largely inferior to the one of an ordinary Reactor for the same energy produced. Schemes are proposed which make a {open_quotes}melt-down{close_quotes} virtually impossible. The conversion ratio, namely the rate of production of {sup 233}U relative to consumption is generally larger than unity, which permits production of fuel for other uses. Alternatively the neutron excess can be used to transform unwanted {open_quotes}ashes{close_quotes} into more acceptable elements.

  6. Fluid circulating pump operated by same incident solar energy which heats energy collection fluid

    Collins, E. R.

    1980-01-01

    The application of using a spacecraft solar powered pump terrestrially to reduce or eliminate the need for fossil fuel generated electricity for domestic solar hot water systems was investigated. A breadboard prototype model was constructed utilizing bimetals to convert thermal energy into mechanical motion by means of a toggle operated shutter mechanism. Although it did not meet expected thermal efficiency, the prototype model was sufficient to demonstrate the mechanical concept.

  7. Radiometric measurements of wall temperatures in the 800 K to 1150 K range for a quartz radiant heating tube

    Blevins, L.G.; Sivathanu, Y.R.; Gore, J.P.; Shahien, M.A.

    1995-01-01

    Many industrial applications require heat transfer to a load in an inert environment, which can be achieved by using gas-fired radiant tubes. A radiant tube consists of a flame confined in a cylindrical metal or ceramic chamber. The flame heats the tube wall, which in turn radiates to the load. One important characteristic of radiant heating tubes is wall temperature uniformity. Numerical models of radiant tubes have been used to predict wall temperatures, but there is a lack of experimental data for validation. Recently, Namazian et al., Singh and Gorski, and Peters et al. have measured wall temperature profiles of radiant tubes using thermocouples. 13 refs., 3 figs

  8. Solar hybrid cooling system for high-tech offices in subtropical climate - Radiant cooling by absorption refrigeration and desiccant dehumidification

    Fong, K.F.; Chow, T.T.; Lee, C.K.; Lin, Z.; Chan, L.S.

    2011-01-01

    Highlights: → A solar hybrid cooling system is proposed for high-tech offices in subtropical climate. → An integration of radiant cooling, absorption refrigeration and desiccant dehumidification. → Year-round cooling and energy performances were evaluated through dynamic simulation. → Its annual primary energy consumption was lower than conventional system up to 36.5%. → The passive chilled beams were more energy-efficient than the active chilled beams. - Abstract: A solar hybrid cooling design is proposed for high cooling load demand in hot and humid climate. For the typical building cooling load, the system can handle the zone cooling load (mainly sensible) by radiant cooling with the chilled water from absorption refrigeration, while the ventilation load (largely latent) by desiccant dehumidification. This hybrid system utilizes solar energy for driving the absorption chiller and regenerating the desiccant wheel. Since a high chilled water temperature generated from the absorption chiller is not effective to handle the required latent load, desiccant dehumidification is therefore involved. It is an integration of radiant cooling, absorption refrigeration and desiccant dehumidification, which are powered up by solar energy. In this study, the application potential of the solar hybrid cooling system was evaluated for the high-tech offices in the subtropical climate through dynamic simulation. The high-tech offices are featured with relatively high internal sensible heat gains due to the intensive office electric equipment. The key performance indicators included the solar fraction and the primary energy consumption. Comparative study was also carried out for the solar hybrid cooling system using two common types of chilled ceilings, the passive chilled beams and active chilled beams. It was found that the solar hybrid cooling system was technically feasible for the applications of relatively higher cooling load demand. The annual primary energy

  9. Mathematical Modeling of Radiant Heat Transfer in Mirror Systems Considering Deep Reflecting Surface Defects

    V. V. Leonov

    2014-01-01

    Full Text Available When designing large-sized mirror concentrating systems (MCS for high-temperature solar power plants, one must have at disposal reasonably reliable and economical methods and tools, making it possible to analyze its characteristics, to predict them depending on the operation conditions and accordingly to choose the most suitable system for the solution of particular task.Experimental determination of MCS characteristics requires complicated and expensive experimentation, having significant limitations on interpretation of the results, as well as limitations imposed due to the size of the structure. Therefore it is of particular interest to develop a mathematical model capable of estimating power characteristics of MCS considering the influence of operating conditions, design features, roughness and other surface defects.For efficient solution of the tasks the model must ensure simulation of solar radiant flux as well as simulation of geometrical and optical characteristics of reflection surface and their interaction. In this connection a statistical mathematical model of radiation heat exchange based on use of Monte Carlo methods and Finite Element Method was developed and realized in the software complex, making it possible to determine main characteristics of the MCS.In this paper the main attention is given to definition of MCS radiation characteristics with account for deep reflecting surface defects (cavities, craters. Deep cavities are not typical for MCS, but their occurrence is possible during operation as a result of erosion or any physical damage. For example, for space technology it is primarily micrometeorite erosion.

  10. Analysis of directional radiative behavior and heating efficiency for a gas-fired radiant burner

    Li, B.X.; Lu, Y.P.; Liu, L.H.; Kudo, K.; Tan, H.P.

    2005-01-01

    For the purpose of energy conservation and uniform heating of object surface, a gas-fired porous radiant burner with a bundle of reflecting tubes is developed. A physical model is developed to simulate the directional radiative behavior of this heating device, in which the Monte Carlo method based on the concept of radiation distribution factor is used to compute the directional radiative behavior. The effects of relating parameters on the directional behavior of radiative heating and the heating efficiency are analyzed. With the increase of the length-to-radius ratio of tube, the radiation heating efficiency decreases, but the radiation energy incident on the object surface is more collimated. The radiation heating efficiency increases with the specular reflectivity. With the increase in length of tube segment with specular reflective surface, the radiation heating efficiency increases, but the extent of concentration and collimation of radiative energy decreases. For real design of the heating device, some trade-offs are needed to balance the radiation heating efficiency and the uniformity of radiative heating of object surface

  11. Reducing Operating Costs and Energy Consumption at Water Utilities

    Due to their unique combination of high energy usage and potential for significant savings, utilities are turning to energy-efficient technologies to help save money. Learn about cost and energy saving technologies from this brochure.

  12. Numeric kinetic energy operators for molecules in polyspherical coordinates

    Sadri, Keyvan; Meyer, Hans-Dieter; Lauvergnat, David; Gatti, Fabien

    2012-01-01

    Generalized curvilinear coordinates, as, e.g., polyspherical coordinates, are in general better adapted to the resolution of the nuclear Schrödinger equation than rectilinear ones like the normal mode coordinates. However, analytical expressions of the kinetic energy operators (KEOs) for molecular systems in polyspherical coordinates may be prohibitively complicated for large systems. In this paper we propose a method to generate a KEO numerically and bring it to a form practicable for dynamical calculations. To examine the new method we calculated vibrational spectra and eigenenergies for nitrous acid (HONO) and compare it with results obtained with an exact analytical KEO derived previously [F. Richter, P. Rosmus, F. Gatti, and H.-D. Meyer, J. Chem. Phys. 120, 6072 (2004)]. In a second example we calculated π→π* photoabsorption spectrum and eigenenergies of ethene (C 2 H 4 ) and compared it with previous work [M. R. Brill, F. Gatti, D. Lauvergnat, and H.-D. Meyer, Chem. Phys. 338, 186 (2007)]. In this ethene study the dimensionality was reduced from 12 to 6 by freezing six internal coordinates. Results for both molecules show that the proposed method for obtaining an approximate KEO is reliable for dynamical calculations. The error in eigenenergies was found to be below 1 cm −1 for most states calculated.

  13. Experimental investigation and feasibility analysis on a capillary radiant heating system based on solar and air source heat pump dual heat source

    Zhao, M.; Gu, Z.L.; Kang, W.B.; Liu, X.; Zhang, L.Y.; Jin, L.W.; Zhang, Q.L.

    2017-01-01

    Graphical abstract: (a) Vertical temperature gradient in Case 3, (b) PMV and PPD of the test room in Case 3, (c) operating time of SPCTS and ASHP systems in Case 3 and (d) the proportion of SPCTS operating time. - Highlights: • A capillary heating system based on solar and air source heat pump was developed. • Influence of supply water temperature on solar energy saving rate was investigated. • Heating performance and thermal comfort of capillary heating system were analyzed. • Low temperature heating with capillary is suitable for solar heating system. - Abstract: Due to sustainable development, solar energy has drawn much attention and been widely applied in buildings. However, the application of solar energy is limited because of its instability, intermittency and low energy density in winter. In order to use low density and instable solar energy source for heating and improve the utilization efficiency of solar energy, a solar phase change thermal storage (SPCTS) heating system using a radiant-capillary-terminal (RCT) to effectively match the low temperature hot water, a phase change thermal storage (PCTS) to store and continuously utilize the solar energy, and an air source heat pump (ASHP) as an alternate energy, was proposed and set up in this research. Series of experiments were conducted to obtain the relation between the solar radiation utilization rate and the heating supply temperatures, and to evaluate the performance of the RCT module and the indoor thermal environment of the system for its practical application in a residential building in the north-western City of Xi’an, China. The results show that energy saving of the solar heating system can be significantly improved by reducing the supplied water temperature, and the supplied water temperature of the RCT would be no more than 35 °C. The capillary radiation heating can adopt a lower water temperature and create a good thermal comfort environment as well. These results may lead to the

  14. Ignition of Cellulosic Paper at Low Radiant Fluxes

    White, K. Alan

    1996-01-01

    The ignition of cellulosic paper by low level thermal radiation is investigated. Past work on radiative ignition of paper is briefly reviewed. No experimental study has been reported for radiative ignition of paper at irradiances below 10 Watts/sq.cm. An experimental study of radiative ignition of paper at these low irradiances is reported. Experimental parameters investigated and discussed include radiant power levels incident on the sample, the method of applying the radiation (focussed vs. diffuse Gaussian source), the presence and relative position of a separate pilot ignition source, and the effects of natural convection (buoyancy) on the ignition process in a normal gravity environment. It is observed that the incident radiative flux (in W/sq.cm) has the greatest influence on ignition time. For a given flux level, a focussed Gaussian source is found to be advantageous to a more diffuse, lower amplitude, thermal source. The precise positioning of a pilot igniter relative to gravity and to the fuel sample affects the ignition process, but the precise effects are not fully understood. Ignition was more readily achieved and sustained with a horizontal fuel sample, indicating the buoyancy plays a role in the ignition process of cellulosic paper. Smoldering combustion of doped paper samples was briefly investigated, and results are discussed.

  15. Design and construction of a regenerative radiant tube burner

    Henao, Diego Alberto; Cano C, Carlos Andres; Amell Arrieta, Andres A.

    2002-01-01

    The technological development of the gas industry in Colombia, aiming at efficient and safe use of the natural gas, requires the assimilation and adaptation of new generation, technologies for this purpose in this article results are presented on the design, construction and characterization of a prototype of a burner of regenerative radiant robe with a thermal power of 9,94 kW and a factor of air 1,05. This system takes advantage of the high exit temperature of the combustion smokes, after they go trough a metallic robe where they transfer the heat by radiation, to heat a ceramic channel that has the capacity to absorbing a part of the heat of the smokes and then transferring them to a current of cold air. The benefits of air heating are a saving in fuel, compared with other processes that don't incorporate the recovery of heat from the combustion gases. In this work it was possible to probe a methodology for the design of this type of burners and to reach maximum temperatures of heating of combustion air of 377,9 centigrade degrees, using a material available in the national market, whose regenerative properties should be studied in depth

  16. Automatic drawing and CAD actualization in processing data of radiant sampling in physics prospect

    Liu Jinsheng

    2010-01-01

    In this paper discussed a method of processing radiant sampling data with computer. By this method can get expain the curve of radiant sampling data, and we can combine mineral masses and analyse and calculate them, then record the result on Notebook. There are many merites of this method: easy to learn, simple to use, high efficient. It adapts to all sorts of mines. (authors)

  17. Automatic drawing and cad actualiztion in processing data of radiant sampling in physics prospect

    Liu Jinsheng

    2010-01-01

    In this paper discussed a method of processing radiant sampling data with computer. By this method can get explain the curve of radiant sampling data, and we can combine mineral masses and analyses and calculate them, then record the result on Notebook. There are many merites of this method: easy to learn, simple to use, high efficient. It adapts to all sorts of mines. (authors)

  18. General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

    H, Jorge A Rueda [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Escuela de Fisica, Universidad Industrial de Santander, A.A. 678, Bucaramanga (Colombia); Nunez, L A [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Centro Nacional de Calculo Cientifico, Universidad de Los Andes, CeCalCULA, Corporacion Parque Tecnologico de Merida, Merida 5101, Venezuela (Venezuela)

    2007-05-15

    An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strong of the shock increases the speed of the fluid to relativistic ones and for some critical values is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong energy condition. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure.

  19. General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

    H, Jorge A Rueda; Nunez, L A

    2007-01-01

    An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strong of the shock increases the speed of the fluid to relativistic ones and for some critical values is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong energy condition. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure

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

    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.

  1. Radiant heat increases piglets’ use of the heated creep area on the critical days after birth

    Larsen, Mona Lilian Vestbjerg; Thodberg, Karen; Pedersen, Lene Juul

    2017-01-01

    The aim of the present study was to investigate how piglets’ use of a creep area is affected by using radiant heat compared to an incandescent light bulb. It was hypothesised that radiant heat would increase the use of the creep area. Twenty litters were randomly assigned to one of two heat sources...... in the creep area: (1) an incandescent light bulb (STANDARD, n=10) or (2) a radiant heat source (RADIANT, n=10) with five of each type of heat source in each of two batches. Observations on piglets’ position in the pen were made by scan sampling every ten minutes in a 4-hour period from 1100 to 1500 h on day 1......–7, 14 and 21 post partum. A higher percentage of piglets in the creep area was seen for RADIANT litters compared to STANDARD litters on day 2 (P=0.002) and day 3 (P=0.005), and percentage of piglets in the creep area increased for RADIANT litters from day 1 to 2 (P

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

    Weiliang Liu

    2018-04-01

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

  3. Energy-efficient Ship Operation – Training Requirements and Challenges

    Michael Baldauf

    2013-06-01

    Full Text Available The International Maritime Organization (IMO, through its Maritime Environmental Protection Committee (MEPC, has been carrying out substantive work on the reduction and limitation of greenhouse gas emissions from international shipping since 1997, following the adoption of the Kyoto Protocol and the 1997 MARPOL Conference. While to date no mandatory GHG instrument for international shipping has been adopted, IMO has given significant consideration of the matter and has been working in accordance with an ambitious work plan with a view to adopting a package of technical provisions. Beside the efforts undertaken by IMO, it is assumed that e.g. optimized manoeuvring regimes have potential to contribute to a reduction of GHG emissions. Such procedures and supporting technologies can decrease the negative effects to the environment and also may reduce fuel consumption. However, related training has to be developed and to be integrated into existing course schemes accordingly. IMO intends to develop a Model Course aiming at promoting the energy-efficient operation of ships. This Course will contribute to the IMO’s environmental protection goals as set out in resolutions A.947(23 and A.998(25 by promulgating industry “best practices”, which reduce greenhouse gas emissions and the negative impact of global shipping on climate change. In this paper the outline of the research work will be introduced and the fundamental ideas and concepts are described. A concept for the overall structure and the development of suggested detailed content of the draft Model course will be exemplarily explained. Also, a developed draft module for the model course with samples of the suggested integrated practical exercises will be introduced and discussed. The materials and data in this publication have been obtained partly through capacity building research project of IAMU kindly supported by the International Association of Maritime Universities (IAMU and The Nippon

  4. Energy efficiency and reliability solutions for rail operations and facilities.

    2014-11-01

    The objectives of the study included examining energy consumption of : the facilities comprising the three major rail yards on the New Haven Rail Line as : well as platform stations and identifying energy efficiency and cost savings : opportunities f...

  5. Theoretical/best practice energy use in metalcasting operations

    Schifo, J. F. [KERAMIDA Environmental, Inc., Indianapolis, IN (United States); Radia, J. T. [KERAMIDA Environmental, Inc., Indianapolis, IN (United States)

    2004-05-01

    This study determined the theoretical minimum energy requirements for melting processes for all ferrous and noferrous engenieering alloys. Also the report details the Best Practice energy consumption for the industry.

  6. An Assessment of Operational Energy Capability Improvement Fund (OECIF) Programs 17-S-2544

    2017-09-19

    power management technologies for high pulse power systems 2. Wireless transmission of energy...efficiently in operations 4** 2017 1) Thermal and power management technologies for high pulse power systems 2) Wireless transmission of energy in...in operations NA3 FY 2017 1) Thermal and power management technologies for high pulse power systems NA4 2) Wireless transmission of energy in the

  7. 16 CFR 305.5 - Determinations of estimated annual energy consumption, estimated annual operating cost, and...

    2010-01-01

    ... consumption, estimated annual operating cost, and energy efficiency rating, and of water use rate. 305.5... RULE CONCERNING DISCLOSURES REGARDING ENERGY CONSUMPTION AND WATER USE OF CERTAIN HOME APPLIANCES AND... § 305.5 Determinations of estimated annual energy consumption, estimated annual operating cost, and...

  8. 75 FR 57299 - First Energy Nuclear Operating Company; Notice of Receipt and Availability of Application for...

    2010-09-20

    ... NUCLEAR REGULATORY COMMISSION [NRC-2010-0298; Docket No. 50-346] First Energy Nuclear Operating Company; Notice of Receipt and Availability of Application for Renewal of Davis Besse Nuclear Power...Energy Nuclear Operating Company, filed pursuant to Section 104(b) of the Atomic Energy Act of 1954, as...

  9. Proceedings of International Symposium on Energy Co-operation in North East Asia

    NONE

    2001-06-01

    This proceedings are for the International Symposium on Energy Co-operation in North-East Asia, organized by Korea Energy Economics Institute, Institute of Energy Economics, Japan, and United Nations Economic and Social Commission for Asia and the Pacific, held on June 2001 at Sheraton Walker Hill Hotel in Seoul, Korea. The major themes discussed are following: 1.Energy Profile, Outlook and Perspectives on Regional Co-operation in Northeast Asia 2.Future Challenges in the Energy Sector in Northeast Asia 3.Perspectives of Energy Co-operation in Northeast Asia.

  10. A comprehensive framework to quantify energy savings potential from improved operations of commercial building stocks

    Azar, Elie; Menassa, Carol C.

    2014-01-01

    While studies highlight the significant impact of actions performed by occupants and facility managers on building energy performance, current policies ignore the importance of human actions and the potential energy savings from a more efficient operation of building systems. This is mainly attributed to the lack of methods that evaluate non-technological drivers of energy use for large stocks of commercial buildings to support policy making efforts. Therefore, this study proposes a scientific approach to quantifying the energy savings potential due to improved operations of any stock of commercial buildings. The proposed framework combines energy modeling techniques, studies on human actions in buildings, and surveying and sampling methods. The contributions of this study to energy policy are significant as they reinforce the role of human actions in energy conservation, and support efforts to integrate operation-focused solutions in energy conservation policy frameworks. The framework's capabilities are illustrated in a case study performed on the stock of office buildings in the United States (US). Results indicate a potential 21 percent reduction in the current energy use levels of these buildings through realistic changes in current building operation patterns. - Highlights: • Human actions highly influence energy performance of commercial building stocks. • It is challenging to quantify operation-related energy savings potential. • The proposed framework quantifies potential energy savings from improved operations. • The framework can be applied on any stock of commercial buildings. • Applications include support for operation-focused solutions in energy policies

  11. Coordinated Optimal Operation Method of the Regional Energy Internet

    Rishang Long

    2017-05-01

    Full Text Available The development of the energy internet has become one of the key ways to solve the energy crisis. This paper studies the system architecture, energy flow characteristics and coordinated optimization method of the regional energy internet. Considering the heat-to-electric ratio of a combined cooling, heating and power unit, energy storage life and real-time electricity price, a double-layer optimal scheduling model is proposed, which includes economic and environmental benefit in the upper layer and energy efficiency in the lower layer. A particle swarm optimizer–individual variation ant colony optimization algorithm is used to solve the computational efficiency and accuracy. Through the calculation and simulation of the simulated system, the energy savings, level of environmental protection and economic optimal dispatching scheme are realized.

  12. Dependence of calculus retropulsion dynamics on fiber size and radiant exposure during Ho:YAG lithotripsy.

    Lee, Ho; Ryan, Robert T; Kim, Jeehyun; Choi, Bernard; Arakeri, Navanit V; Teichman, Joel M H; Welch, A J

    2004-08-01

    During pulsed laser lithotripsy, the calculus is subject to a strong recoil momentum which moves the calculus away from laser delivery and prolongs the operation. This study was designed to quantify the recoil momentum during Ho:YAG laser lithotripsy. The correlation among crater shape, debris trajectory, laser-induced bubble and recoil momentum was investigated. Calculus phantoms made from plaster of Paris were ablated with free running Ho:YAG lasers. The dynamics of recoil action of a calculus phantom was monitored by a high-speed video camera and the laser ablation craters were examined with Optical Coherent Tomography (OCT). Higher radiant exposure resulted in larger ablation volume (mass) which increased the recoil momentum. Smaller fibers produced narrow craters with a steep contoured geometry and decreased recoil momentum compared to larger fibers. In the presence of water, recoil motion of the phantom deviated from that of phantom in air. Under certain conditions, we observed the phantom rocking towards the fiber after the laser pulse. The shape of the crater is one of the major contributing factors to the diminished recoil momentum of smaller fibers. The re-entrance flow of water induced by the bubble collapse is considered to be the cause of the rocking of the phantom.

  13. Tunnel effect wave energy detection

    Kaiser, William J. (Inventor); Waltman, Steven B. (Inventor); Kenny, Thomas W. (Inventor)

    1995-01-01

    Methods and apparatus for measuring gravitational and inertial forces, magnetic fields, or wave or radiant energy acting on an object or fluid in space provide an electric tunneling current through a gap between an electrode and that object or fluid in space and vary that gap with any selected one of such forces, magnetic fields, or wave or radiant energy acting on that object or fluid. These methods and apparatus sense a corresponding variation in an electric property of that gap and determine the latter force, magnetic fields, or wave or radiant energy in response to that corresponding variation, and thereby sense or measure such parameters as acceleration, position, particle mass, velocity, magnetic field strength, presence or direction, or wave or radiant energy intensity, presence or direction.

  14. Save Energy Dollars with DOE Operations and Maintenance Guide

    Appel, Margo

    2010-01-01

    At budget-crunching time, school administrators and business officials sometimes find themselves trimming the district's budget for teachers, textbooks, and technology in order to cover ballooning energy costs. Nearly one-third of the energy consumed in the average U.S. school is wasted. The country's least efficient schools use four times more…

  15. Unified System-Level Modeling of Intermittent Renewable Energy Sources and Energy Storage for Power System Operation

    Heussen, Kai; Koch, Stephan; Ulbig, Andreas

    2011-01-01

    The system-level consideration of inter- mittent renewable energy sources and small-scale en- ergy storage in power systems remains a challenge as either type is incompatible with traditional operation concepts. Non-controllability and energy-constraints are still considered contingent cases...... in market-based operation. The design of operation strategies for up to 100 % renewable energy systems requires an explicit consideration of non-dispatchable generation and stor- age capacities, as well as the evaluation of operational performance in terms of energy eciency, reliability, environmental...... impact and cost. By abstracting from technology-dependent and physical unit properties, the modeling framework presented and extended in this pa- per allows the modeling of a technologically diverse unit portfolio with a unied approach, whilst establishing the feasibility of energy-storage consideration...

  16. 75 FR 17407 - Energy Efficiency of the Natural Gas Infrastructure and Operations Conference; Notice of Public...

    2010-04-06

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD09-11-000] Energy Efficiency of the Natural Gas Infrastructure and Operations Conference; Notice of Public Conference March 31... Room on the second floor of the offices of the Federal Energy Regulatory Commission, 888 First Street...

  17. 77 FR 24192 - SIG Energy, LLLP v. California Independent System Operator Corporation; Notice of Complaint

    2012-04-23

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL12-55-000] SIG Energy, LLLP v. California Independent System Operator Corporation; Notice of Complaint Take notice that on.... 824(e) and 825(e), SIG Energy, LLLP (Complainant) filed a formal complaint against the California...

  18. Effect of gas filling pressure and operation energy on ion and neutron emission in a medium energy plasma focus device

    Niranjan, Ram; Rout, R. K.; Srivastava, Rohit; Kaushik, T. C.

    2018-03-01

    The effects of gas filling pressure and operation energy on deuterium ions and neutrons have been studied in a medium energy plasma focus device, MEPF-12. The deuterium gas filling pressure was varied from 1 to 10 mbar at an operation energy of 9.7 kJ. Also, the operation energy was varied from 3.9 to 9.7 kJ at a deuterium gas filling pressure of 4 mbar. Time resolved emission of deuterium ions was measured using a Faraday cup. Simultaneously, time integrated and time resolved emissions of neutrons were measured using a silver activation detector and plastic scintillator detector, respectively. Various characteristics (fluence, peak density, and most probable energy) of deuterium ions were estimated using the Faraday cup signal. The fluence was found to be nearly independent of the gas filling pressure and operation energy, but the peak density and most probable energy of deuterium ions were found to be varying. The neutron yield was observed to be varying with the gas filling pressure and operation energy. The effect of ions on neutrons emission was observed at each operation condition.

  19. Modeling of hydronic radiant cooling of a thermally homeostatic building using a parametric cooling tower

    Ma, Peizheng; Wang, Lin-Shu; Guo, Nianhua

    2014-01-01

    Highlights: • Investigated cooling of thermally homeostatic buildings in 7 U.S. cities by modeling. • Natural energy is harnessed by cooling tower to extract heat for building cooling. • Systematically studied possibility and conditions of using cooling tower in buildings. • Diurnal ambient temperature amplitude is taken into account in cooling tower cooling. • Homeostatic building cooling is possible in locations with large ambient T amplitude. - Abstract: A case is made that while it is important to mitigate dissipative losses associated with heat dissipation and mechanical/electrical resistance for engineering efficiency gain, the “architect” of energy efficiency is the conception of best heat extraction frameworks—which determine the realm of possible efficiency. This precept is applied to building energy efficiency here. Following a proposed process assumption-based design method, which was used for determining the required thermal qualities of building thermal autonomy, this paper continues this line of investigation and applies heat extraction approach investigating the extent of building partial homeostasis and the possibility of full homeostasis by using cooling tower in one summer in seven selected U.S. cities. Cooling tower heat extraction is applied parametrically to hydronically activated radiant-surfaces model-buildings. Instead of sizing equipment as a function of design peak hourly temperature as it is done in heat balance design-approach of selecting HVAC equipment, it is shown that the conditions of using cooling tower depend on both “design-peak” daily-mean temperature and the distribution of diurnal range in hourly temperature (i.e., diurnal temperature amplitude). Our study indicates that homeostatic building with natural cooling (by cooling tower alone) is possible only in locations of special meso-scale climatic condition such as Sacramento, CA. In other locations the use of cooling tower alone can only achieve homeostasis

  20. Energy Technology Initiatives 2013. Implementation through Multilateral Co-operation

    NONE

    2013-07-01

    Ensuring energy security and addressing climate change cost-effectively are key global challenges. Tackling these issues will require efforts from stakeholders worldwide. To find solutions, the public and private sectors must work together, sharing burdens and resources, while at the same time multiplying results and outcomes. Through its broad range of multilateral technology initiatives (Implementing Agreements), the IEA enables member and non-member countries, businesses, industries, international organisations and non-governmental organisations to share research on breakthrough technologies, to fill existing research gaps, to build pilot plants and to carry out deployment or demonstration programmes across the energy sector. This publication highlights the most significant recent achievements of the IEA Implementing Agreements. At the core of the IEA energy technology network, these initiatives are a fundamental building block for facilitating the entry of new and improved energy technologies into the marketplace.

  1. Operational Energy Metrics: Increasing Flexibility While Reducing Vulnerability

    2010-03-01

    procurement decisions with a greater level of fidelity concerning the cost- benefit analysis for systems lifetime cost of energy. Furthermore, it...or we have to RTB, we’re BINGO -fuel48”? As General Ronald Keys, USAF (RET.) stated when discussing energy efficiency and mission effectiveness...of Defense change to fully value the delivered cost of fuel, the sooner joint force commanders will reap the “strategic benefits of reallocating

  2. Optimal Energy Management of Multi-Microgrids with Sequentially Coordinated Operations

    Nah-Oak Song

    2015-08-01

    Full Text Available We propose an optimal electric energy management of a cooperative multi-microgrid community with sequentially coordinated operations. The sequentially coordinated operations are suggested to distribute computational burden and yet to make the optimal 24 energy management of multi-microgrids possible. The sequential operations are mathematically modeled to find the optimal operation conditions and illustrated with physical interpretation of how to achieve optimal energy management in the cooperative multi-microgrid community. This global electric energy optimization of the cooperative community is realized by the ancillary internal trading between the microgrids in the cooperative community which reduces the extra cost from unnecessary external trading by adjusting the electric energy production amounts of combined heat and power (CHP generators and amounts of both internal and external electric energy trading of the cooperative community. A simulation study is also conducted to validate the proposed mathematical energy management models.

  3. Action plan for Nordic energy co-operation 2006-2009

    2005-01-01

    The Action Plan for Nordic Energy Co-operation 2006-2009 is targeted at creating a visible and sustainable contribution to solving the most important and politically most relevant energy policy challenges faced by the Nordic region. The plan concentrates on three main areas: Energy markets; Sustainable energy system; and Nordic impact on the international agenda. The Action Plan is the energy sector's contribution to the implementation of the Nordic strategy 'Sustainable Development - New Bearing for the Nordic Countries' and to a number of the Nordic Council's recommendations for the development of the Nordic energy sector. An important element of the implementation of the action plan is on-going contact and information sharing between the Nordic Energy Policy co-operation and the Nordic Energy Research. The continues dialogue between the Nordic Council of Energy Ministers and The Nordic Council on future energy policy challenges will likewise be an important part of the political process. (BA)

  4. First operational experience with the LHC machine protection system when operating with beam energies beyond the 100MJ range

    Assmann, R; Ferro-Luzzi, M; Goddard, B; Lamont, M; Schmidt, R; Siemko, A; Uythoven, J; Wenninger, J; Zerlauth, M

    2012-01-01

    The Large Hadron Collider (LHC) at CERN has made remarkable progress during 2011, surpassing its ambitious goal for the year in terms of luminosity delivered to the LHC experiments. This achievement was made possible by a progressive increase of beam intensities by more than 5 orders of magnitude during the first months of operation, reaching stored beam energies beyond the 100MJ range at the end of the year, less than a factor of 4 from the nominal design value. The correct functioning of the machine protection systems is vital during the different operational phases, for initial operation and even more when approaching nominal beam parameters where already a small fraction of the stored energy is sufficient to damage accelerator equipment or experiments in case of uncontrolled beam loss. Safe operation of the machine in presence of such high intensity proton beams is guaranteed by the interplay of many different systems: beam dumping system, beam interlocks, beam instrumentation, equipment monitoring, colli...

  5. Operating characteristics of a prototype high energy gamma-ray telescope

    Jenkins, T.L.; Frye, G.M.; Hall, C.J.; Owens, A.; Pendleton, G.N.; Carter, J.N.; Ramsden, D.; Agrinier, B.; Bonfand, E.; Refloch, A.; Tabary, A.

    1985-08-01

    We have operated a prototype coded aperture telescope in a tagged photon beam ranging in energy from 23 to 123 MeV. The purpose of the experiment was to demonstrate the feasibility of operating a coded aperture mask telescope in this energy region. This paper reports some preliminary results and conclusions drawn from some of the data resulting from this experiment

  6. Operating results and experience and operating regimes in changing demands of energy world

    Hobza, L.

    2004-01-01

    In this paper, there are stated some operating results and experience obtained from trial operation of Temelin NPP. In Europe, Temelin NPP is presently one of the latest implemented projects of the series of VVER 1000 nuclear units with proven V-320 pressurized water reactor. The distinction between Temelin NPP and original project lays mainly in supply of nuclear fuel and in I and C systems delivered by Westinghouse Company. Temelin NPP has passed through commissioning period and trial operation. The main goal of the trial operation was to meet the requirements of section 2, par. 4, point b) of Decree No. 106/98 Sb. and verification of project parameters and stability of operation, and the situation leading to violation of safety functions fulfilment according to Pre-operational Safety Report should not occur. The integral part of trial operation assessment was also successful performing of determined monitoring programmes, first refuelling and performing of prescribed tests and operational inspections. Simultaneously, first experience was obtained with nuclear fuel; providing of ancillary services; reliability of important components; operation of turbine-generator 1000 MW; chemical regime; influence to environment; and quality of contractors. As safety is the most important indicator, it can be stated that: no facts which would lead to decreasing of safety systems operability have been detected; no facts which would lead to negative affecting of barriers against fading the radioactivity into both working areas and environment, have been detected; good condition of fire safety has been continuously documented; requirements of limits for releasing waste water into environment have been continuously complied with; requirements of limits for releasing radioactive substances (in gaseous and/or liquid state) into environment have been continuously complied with. From the operation regimes point of view is clear, that it would be suitable for the power plant if the

  7. Population exposures from US Department of Energy operations

    Welty, C.G. Jr.; Kennedy, W.E. Jr.; Hawley, K.A.

    1987-09-01

    The DOE annually collects information concerning emissions and calculates radiation doses to the population within an 80-kilometer radius of its operating nuclear installations. For most of these installations, the resulting concentrations in environmental media are too low to be adequately measured; at those sites, computer modeling is used to predict values for estimating public radiation doses. The estimated public doses are evaluated by the DOE to ensure that its operations are in compliance with its public radiation dose standards. This paper describes the calculated population dose from all operating DOE installations for recent years, including radionuclide-specific contributions to public dose and comparisons with the expected population dose resulting from all background sources of radiation. The year-to-year trends since 1979 are shown, together with a description of the major reasons for the trends. Of significance to the dose estimation for this period was the change to using the effective-dose-equivalent factors. We conclude that the estimated radiation doses of combined DOE operations are small compared to the radiation dose received each year by the same population from natural sources of radioactivity. 5 refs., 4 figs., 2 tabs.

  8. Pollutant emissions reduction and performance optimization of an industrial radiant tube burner

    Scribano, Gianfranco; Solero, Giulio; Coghe, Aldo [Dipartimento di Energetica, Politecnico di Milano, via La Masa, 34, 20156 Milano (Italy)

    2006-07-15

    This paper presents the results of an experimental investigation performed upon a single-ended self-recuperative radiant tube burner fuelled by natural gas in the non-premixed mode, which is used in the steel industry for surface treatment. The main goal of the research activity was a systematic investigation of the burner aimed to find the best operating conditions in terms of optimum equivalence ratio, thermal power and lower pollutant emissions. The analysis, which focused on the main parameters influencing the thermal efficiency and pollutant emissions at the exhaust (NO{sub x} and CO), has been carried out for different operating conditions of the burner: input thermal powers from 12.8 up to 18kW and equivalence ratio from 0.5 (very lean flame) to 0.95 (quasi-stoichiometric condition). To significantly reduce pollutant emissions ensuring at the same time the thermal requirements of the heating process, it has been developed a new burner configuration, in which a fraction of the exhaust gases recirculates in the main combustion region through a variable gap between the burner efflux and the inner flame tube. This internal recirculation mechanism (exhaust gases recirculation, EGR) has been favoured through the addition of a pre-combustion chamber terminated by a converging nozzle acting as a mixing/ejector to promote exhaust gas entrainment into the flame tube. The most important result of this solution was a decrease of NO{sub x} emissions at the exhaust of the order of 50% with respect to the original burner geometry, for a wide range of thermal power and equivalence ratio. (author)

  9. Ship Integration of Energy Scavenging Technology for Sea Base Operations

    2009-07-01

    Paraschivoiu, I. (2002). Wind Turbine Design with Emphasis on Darrieus Concept. Montreal, QC, Canada: Polytechnic International Press. 23 Pelamis...31 Wind Turbine Production Data..................................................................................... 31 Summary...integration. Lastly, wind turbines are a promising method of harvesting energy. Horizontal axis wind turbines are currently the most developed

  10. Nuclear energy in Asia and regional co-operation

    Ishii, M.

    1997-01-01

    There is increasing concern in East Asia about regional cooperation in the field of nuclear power. At the APEC conference in Osaka in 1995, APEC (Asia Pacific Economic Cooperation) established an Energy Research Center. The center has started to perform joint research forecasts on energy supply and demand for the region. Japan proposed the inauguration of a Conference on Nuclear Safety in Asia at the Moscow Nuclear Energy Summit in 1996. The first conference was held in Tokyo that year. This year, the conference will be held in Seoul. Japan's Atomic Energy Commission sponsors the International Conference for Nuclear Cooperation in Asia every year. This year marks the eighth conference. The outstanding feature of this year's conference was that so many countries stressed regional cooperation. South Korea proposed the installation of a regional online radiation monitoring system. The Philippines asserted the need for a cooperative mechanism on the lines of ASIATOM. Why is so much concern now being focused on nuclear power cooperation in East Asia? What kind of regional cooperation is necessary, and what kind is possible? What are the unique features of nuclear power cooperation in East Asia? These are the points addressed in this paper. (author)

  11. Energy management in mobile devices with the cinder operating system

    Roy, Arjun; Rumble, Stephen M.; Stutsman, Ryan; Levis, Philip; Maziè res, David; Zeldovich, Nickolai

    2011-01-01

    and distribute energy for application use. We identify three key properties of control - isolation, delegation, and subdivision - and show how using these abstractions can achieve them. We also show how the architecture of the HiStar information-flow control

  12. Joint Optimal Design and Operation of Hybrid Energy Storage Systems

    Y. Ghiassi-Farrokhfal (Yashar); C. Rosenberg; S. Keshav (Srinivasam); M.-B. Adjaho (Marie-Benedicte)

    2016-01-01

    markdownabstractThe wide range of performance characteristics of storage technologies motivates the use of a hybrid energy storage systems (HESS) that combines the best features of multiple technologies. However, HESS design is complex, in that it involves the choice of storage technologies, the

  13. Business Case: Sustainable Energy for De-mining Operations

    Buur, Jacob; Finnemann, Winie

    2011-01-01

    small, Danish companies work with an NGO and two university partners to develop a sustainable energy solution for humanitarian landmine removal in Angola as an alternative to the presently used diesel generators. I will discuss the challenges that face the companies, if they are to bring the project...

  14. Probabilistic tools for planning and operating power systems with distributed energy storage

    Klöckl, Bernd; Papaefthymiou, George; Pinson, Pierre

    2008-01-01

    Stochastic energy flows are an increasingly important phenomenon in today's power system planning and operation. They are – among other reasons – caused by large amounts of stochastic generation such as wind. The inclusion of energy storage devices, distributed in future systems (distributed energy...... owners are either the grid operators, the generation owners, or the energy traders. For the grid operators being the DES owners, storage operation will have to be integrated into the planning of the system, therefore multivariate nonparametric time series analysis and synthesis methods have to be applied...... to recorded data of stochastic energy resources. Together with suited storage models, the implications of DES on the planning of the system can then be assessed. For the producers or traders being the owners of the DES, the topic to be addressed is the real-time operation of each storage device in the power...

  15. Linearization of the interaction principle: Analytic Jacobians in the 'Radiant' model

    Spurr, R.J.D.; Christi, M.J.

    2007-01-01

    In this paper we present a new linearization of the Radiant radiative transfer model. Radiant uses discrete ordinates for solving the radiative transfer equation in a multiply-scattering anisotropic medium with solar and thermal sources, but employs the adding method (interaction principle) for the stacking of reflection and transmission matrices in a multilayer atmosphere. For the linearization, we show that the entire radiation field is analytically differentiable with respect to any surface or atmospheric parameter for which we require Jacobians (derivatives of the radiance field). Derivatives of the discrete ordinate solutions are based on existing methods developed for the LIDORT radiative transfer models. Linearization of the interaction principle is completely new and constitutes the major theme of the paper. We discuss the application of the Radiant model and its linearization in the Level 2 algorithm for the retrieval of columns of carbon dioxide as the main target of the Orbiting Carbon Observatory (OCO) mission

  16. ENERGY SAVING AT OPERATION OF OUTDOOR SWIMMING POOLS

    V. F. Ivin

    2013-09-01

    Full Text Available Purpose. Energy saving is a major problem in modern power engineering and various energy-consuming devices. They include outdoor swimming pools. In order to maintain them in working condition, especially in winter period, it takes significant amount of thermal energy. Task of heat loss substantial decrease in open swimming pools is considered in the article (on DNURT example. Methodology. The method of determining the mass and heat loss on the basis of criteria equations of heat and mass transfer theory is used. Findings. Calculations of the actual DNURT pool heat loss for different seasons, as for natural convection both for air forced motion above the free water surface are performed. It is shown that for the adiabatic evaporation conditions of water from the pool in winter during blow-off with wind the heat loss can be up to 2 kW/m2 on surface. To reduce these losses it is offered to cover water surface in a pool with a special material with low thermal conductivity on the basis of porous polyethylene during the time when the pool is not used for other purposes. It is shown that the implementation of these standards will reduce the actual heat loss, at least 5-6 times. Originality. The solution of important environmental and energy problem thanks to reducing heat losses by the pool in different times of a year and correspondingly lower emissions of power generating enterprises. Practical value. It is shown that the coating surface of the pool with poorly heat-conducting and easy to install coating will let, at a minimum, to reduce the actual heat loss on 5-6 times and reduce the emissions of power plants generating energy for pool heating.

  17. Energy-saving operation of a converter-fed synchronous machine

    Schmidt, I.; Veszpremi, K. [Technical University of Budapest, Department of Electrical Machines and Drives, Budapest (Hungary)

    1997-12-31

    In the Converter-Fed Synchronous Machine (CFSM) there is no need for forced commutation the CL and CF converters operate with line commutation, the CM is commutated by the machine voltages. This drive is applied mainly for large power and high speed controlled drives. Considering the large power, the investigation of energy-saving operation is important. As in the DC and the induction motor drives the energy-saving operation is implemented by flux control. (orig.) 6 refs.

  18. Renewable energy supply for electric vehicle operations in California

    Papavasiliou, Anthony; Oren, Shmuel S.; Sidhy, Ikhlaq; Kaminsky, Phil; 32nd IAEE International Conference

    2009-01-01

    Due to technological progress, policy thrust and economic circumstances, the large scale integration of renewable energy sources such as wind and solar power is becoming a reality in California, however the variable and unpredictable supply of these renewable resources poses a significant obstacle to their integration. At the same time we are witnessing a strong thrust towards the large scale deployment of electric vehicles which can ideally complement renewable power supply by acting as stor...

  19. Waste to energy plant operation under the influence of market and legislation conditioned changes

    Tomic, Tihomir; Dominkovic, Dominik Franjo; Pfeifer, Antun

    2017-01-01

    , waste-to-energy plants need to be adapted to market operation. This influence is tracked by the gate-fee volatility. The operation of the waste-to-energy plant on electricity markets is simulated by using EnergyPLAN and heat market is simulated in Matlab, based on hourly marginal costs. The results have......In this paper, gate-fee changes of the waste-to-energy plants are investigated in the conditions set by European Union legislation and by the introduction of the new heat market. Waste management and sustainable energy supply are core issues of sustainable development of regions, especially urban...... areas. These two energy flows logically come together in the combined heat and power facility by waste incineration. However, the implementation of new legislation influences quantity and quality of municipal waste and operation of waste-to-energy systems. Once the legislation requirements are met...

  20. Experimental evaluation of heat transfer coefficients between radiant ceiling and room

    Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco

    2009-01-01

    The heat transfer coefficients between radiant surfaces and room are influenced by several parameters: surfaces temperature distributions, internal gains, air movements. The aim of this paper is to evaluate the heat transfer coefficients between radiant ceiling and room in typical conditions...... of occupancy of an office or residential building. Internal gains were therefore simulated using heated cylinders and heat losses using cooled surfaces. Evaluations were developed by means of experimental tests in an environmental chamber. Heat transfer coefficient may be expressed separately for radiation...

  1. Thermal Conditions in a Simulated Office Environment with Convective and Radiant Cooling Systems

    Mustakallio, Panu; Bolashikov, Zhecho Dimitrov; Kostov, Kalin

    2013-01-01

    velocity and turbulent intensity were measured and draft rate levels calculated in the room. Manikin-based equivalent temperature (MBET) was determined by two thermal manikins to identify the impact of the local thermal conditions generated by the studied systems on occupants’ thermal comfort. The results......The thermal conditions in a two person office room were measured with four air conditioning systems: chilled beam (CB), chilled beam with radiant panel (CBR), chilled ceiling with ceiling installed mixing ventilation (CCMV) and four desk partition mounted local radiant cooling panels with mixing...

  2. Three-dimensional simulation of super-radiant Smith-Purcell radiation

    Li, D.; Imasaki, K.; Yang, Z.; Park, Gun-Sik

    2006-01-01

    A simulation of coherent and super-radiant Smith-Purcell radiation is performed in the gigahertz regime using a three-dimensional particle-in-cell code. The simulation model supposes a rectangular grating to be driven by a single electron bunch and a train of periodic bunches, respectively. The true Smith-Purcell radiation is distinguished from the evanescent wave, which has an angle independent frequency lower than the minimum allowed Smith-Purcell frequency. We also find that the super-radiant radiations excited by periodic bunches are emitted at higher harmonics of the bunching frequency and at the corresponding Smith-Purcell angles

  3. Cooling load calculations of radiant and all-air systems for commercial buildings

    Bourdakis, Eleftherios; Bauman, Fred; Schiavon, Stefano

    The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when they are......The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when...

  4. 40 CFR 73.80 - Operation of allowance reserve program for conservation and renewable energy.

    2010-07-01

    ... for conservation and renewable energy. 73.80 Section 73.80 Protection of Environment ENVIRONMENTAL... and Renewable Energy Reserve § 73.80 Operation of allowance reserve program for conservation and renewable energy. (a) General. The Administrator will allocate allowances from the Conservation and...

  5. Fixed, low radiant exposure vs. incremental radiant exposure approach for diode laser hair reduction: a randomized, split axilla, comparative single-blinded trial.

    Pavlović, M D; Adamič, M; Nenadić, D

    2015-12-01

    Diode lasers are the most commonly used treatment modalities for unwanted hair reduction. Only a few controlled clinical trials but not a single randomized controlled trial (RCT) compared the impact of various laser parameters, especially radiant exposure, onto efficacy, tolerability and safety of laser hair reduction. To compare the safety, tolerability and mid-term efficacy of fixed, low and incremental radiant exposures of diode lasers (800 nm) for axillary hair removal, we conducted an intrapatient, left-to-right, patient- and assessor-blinded and controlled trial. Diode laser (800 nm) treatments were evaluated in 39 study participants (skin type II-III) with unwanted axillary hairs. Randomization and allocation to split axilla treatments were carried out by a web-based randomization tool. Six treatments were performed at 4- to 6-week intervals with study subjects blinded to the type of treatment. Final assessment of hair reduction was conducted 6 months after the last treatment by means of blinded 4-point clinical scale using photographs. The primary endpoint was reduction in hair growth, and secondary endpoints were patient-rated tolerability and satisfaction with the treatment, treatment-related pain and adverse effects. Excellent reduction in axillary hairs (≥ 76%) at 6-month follow-up visit after receiving fixed, low and incremental radiant exposure diode laser treatments was obtained in 59% and 67% of study participants respectively (Z value: 1.342, P = 0.180). Patients reported lower visual analogue scale (VAS) pain score on the fixed (4.26) than on the incremental radiant exposure side (5.64) (P diode laser treatments were less painful and better tolerated. © 2015 European Academy of Dermatology and Venereology.

  6. Energy-efficient operation of a booster RF system for Taiwan light source operated in top-up mode

    Yeh, Meng-Shu; Wang, Chaoen; Chang, Lung-Hai; Chung, Fu-Tsai; Yu, Tsung-Chi; Lin, Ming-Chyuan; Chen, Ling-Jhen; Yang, Tz-Te; Chang, Mei-Hsia; Lin, Yu-Han; Tsai, Ming-Hsun; Lo, Chih-Hung; Liu, Zong-Kai

    2015-01-01

    Contemporary light sources operate in a top-up mode to maintain their photon intensity quasi-constant so as to improve significantly the thermal stability of the photon beam and to maximize ultimately the average photon flux at a designed maximum operational beam current. Operating in a top-up mode requires frequent beam injection from the synchrotron booster to the storage ring of the light source, but the injection intervals occupy only a tiny portion of the operational time of the integrated machine. To maintain a high operational reliability, the booster RF system practically operates necessarily under injection conditions around the clock and consumes full electric power whether during top-up injection or not. How to decrease the power consumption of the booster RF system during its stand-by time but not to sacrifice the reliability and availability of the RF system is obviously of fundamental interest for routine operation of the light source in a top-up mode. Here, an energy-efficient operation of a booster RF system adaptive to top-up operation of a light source is proposed that has been developed, realized and integrated into the booster RF system of the Taiwan Light Source (TLS), and routinely operated since the end of year 2008. The klystron cathode current and RF gap voltage of the booster's accelerating RF cavity are both periodically modulated to adapt the injection rhythm during top-up operation, which results in decreased consumption of electric power of the booster RF system by more than 78%. The impact on the reliability and availability of the booster RF system has been carefully monitored during the past five operational years, delivering more than 5000 h scheduled user beam time per year. The booster RF system retains its excellent reliability and availability as previously. Neither a decrease of the service time nor an induced reliability issue from the klystron or any high-power high-voltage component of the transmitter has been

  7. 16 CFR Figure 4 to Subpart A of... - Flooring Radiant Panel Tester Schematic Low Flux End, Elevation

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Flooring Radiant Panel Tester Schematic Low Flux End, Elevation 4 Figure 4 to Subpart A of Part 1209 Commercial Practices CONSUMER PRODUCT SAFETY... Standard Pt. 1209, Subpt. A, Fig. 4 Figure 4 to Subpart A of Part 1209—Flooring Radiant Panel Tester...

  8. Operation strategy analysis of a geothermal step utilization heating system

    Zheng, Guozhong; Li, Feng; Tian, Zhe; Zhu, Neng; Li, Qianru; Zhu, Han

    2012-01-01

    Geothermal energy has been successfully applied in many district heating systems. In order to promote better use of geothermal energy, it is important to analyze the operation strategy of geothermal heating system. This study proposes a comprehensive and systematic operation strategy for a geothermal step utilization heating system (GSUHS). Calculation models of radiator heating system (RHS), radiant floor heating system (RFHS), heat pump (HP), gas boiler (GB), plate heat exchanger (PHE) and pump are first established. Then the operation strategy of the GSUHS is analyzed with the aim to substantially reduce the conventional energy consumption of the whole system. Finally, the energy efficiency and geothermal tail water temperature are analyzed. With the operation strategy in this study, the geothermal energy provides the main heating amount for the system. The heating seasonal performance factor is 15.93. Compared with coal-fired heating, 75.1% of the standard coal equivalent can be saved. The results provide scientific guidance for the application of an operation strategy for a geothermal step utilization heating system. -- Highlights: ► We establish calculation models for the geothermal step utilization heating system. ► We adopt minimal conventional energy consumption to determine the operation strategy. ► The geothermal energy dominates the heating quantity of the whole system. ► The utilization efficiency of the geothermal energy is high. ► The results provide guidance to conduct operation strategy for scientific operation.

  9. The chemical energy unit partial oxidation reactor operation simulation modeling

    Mrakin, A. N.; Selivanov, A. A.; Batrakov, P. A.; Sotnikov, D. G.

    2018-01-01

    The chemical energy unit scheme for synthesis gas, electric and heat energy production which is possible to be used both for the chemical industry on-site facilities and under field conditions is represented in the paper. The partial oxidation reactor gasification process mathematical model is described and reaction products composition and temperature determining algorithm flow diagram is shown. The developed software product verification showed good convergence of the experimental values and calculations according to the other programmes: the temperature determining relative discrepancy amounted from 4 to 5 %, while the absolute composition discrepancy ranged from 1 to 3%. The synthesis gas composition was found out practically not to depend on the supplied into the partial oxidation reactor (POR) water vapour enthalpy and compressor air pressure increase ratio. Moreover, air consumption coefficient α increase from 0.7 to 0.9 was found out to decrease synthesis gas target components (carbon and hydrogen oxides) specific yield by nearly 2 times and synthesis gas target components required ratio was revealed to be seen in the water vapour specific consumption area (from 5 to 6 kg/kg of fuel).

  10. Optimal Planning and Operation Management of a Ship Electrical Power System with Energy Storage System

    Anvari-Moghaddam, Amjad; Dragicevic, Tomislav; Meng, Lexuan

    2016-01-01

    Next generation power management at all scales is highly relying on the efficient scheduling and operation of different energy sources to maximize efficiency and utility. The ability to schedule and modulate the energy storage options within energy systems can also lead to more efficient use...... of the generating units. This optimal planning and operation management strategy becomes increasingly important for off-grid systems that operate independently of the main utility, such as microgrids or power systems on marine vessels. This work extends the principles of optimal planning and economic dispatch...... for the proposed plan is derived based on the solution from a mixed-integer nonlinear programming (MINLP) problem. Simulation results showed that including well-sized energy storage options together with optimal operation management of generating units can improve the economic operation of the test system while...

  11. Research on Energy-Saving Operation Strategy for Multiple Trains on the Urban Subway Line

    Jianqiang Liu

    2017-12-01

    Full Text Available Energy consumption for multiple trains on the urban subway line is predominantly affected by the operation strategy. This paper proposed an energy-saving operation strategy for multiple trains, which is suitable for various line conditions and complex train schedules. The model and operation modes of the strategy are illustrated in detail, aiming to take full use of regenerative braking energy in complex multi-train systems with different departure intervals and dwell times. The computing method is proposed by means of the heuristic algorithm to obtain the optimum operation curve for each train. The simulation result based on a real urban subway line is provided to verify the correctness and effectiveness of the proposed energy-saving operation strategy.

  12. The energy sector in Northeast Asia : new projects, delivery systems and prospects for co-operation

    Ivanov, V.I.

    2000-01-01

    This study examines the needs and opportunities for energy co-operation in Northeast Asia, with particular reference to development of resources in eastern Russia, Siberia and the Far East to supply energy to consumers in Northeast Asia. Given the high projected demand for energy resources, Japan, South Korea and China are compelled to consider diversifying their energy supplies and developing new links with eastern Russia. The environmental degradation caused by coal burning in China is another incentive for looking for sources of natural gas in Eurasia. Russia and Japan are concentrating on the Sakhalin oil and gas projects. China and Russia have agreed to work closely in the energy sector, focusing on a pipeline from the natural gas field near Irkutsk. The challenges lies in developing a co-ordinated approach to energy resource development and use, by modifying energy policies and long-term supply outlooks. Another challenge lies in the fact that private investors and intergovernmental co-operation are required to build an expensive cross-border infrastructure to transport natural gas, electricity and oil. Co-operation is also required to improve energy efficiency, modernize existing facilities and promote cleaner sources of energy, energy conservation and environmental protection. This report examined forecasted energy demand and imports in Northeast Asia and identified opportunities for co-operation. refs., tabs

  13. Effect of ventilation rate on air cleanliness and energy consumption in operation rooms at rest.

    Lee, Shih-Tseng; Liang, Ching-Chieh; Chien, Tsung-Yi; Wu, Feng-Jen; Fan, Kuang-Chung; Wan, Gwo-Hwa

    2018-02-27

    The interrelationships between ventilation rate, indoor air quality, and energy consumption in operation rooms at rest are yet to be understood. We investigate the effect of ventilation rate on indoor air quality indices and energy consumption in ORs at rest. The study investigates the air temperature, relative humidity, concentrations of carbon dioxide, particulate matter (PM), and airborne bacteria at different ventilation rates in operation rooms at rest of a medical center. The energy consumption and cost analysis of the heating, ventilating, and air conditioning (HVAC) system in the operation rooms at rest were also evaluated for all ventilation rates. No air-conditioned operation rooms had very highest PM and airborne bacterial concentrations in the operation areas. The bacterial concentration in the operation areas with 6-30 air changes per hour (ACH) was below the suggested level set by the United Kingdom (UK) for an empty operation room. A 70% of reduction in annual energy cost by reducing the ventilation rate from 30 to 6 ACH was found in the operation rooms at rest. Maintenance of operation rooms at ventilation rate of 6 ACH could save considerable amounts of energy and achieve the goal of air cleanliness.

  14. The operational performance of “net zero energy building”: A study in China

    Zhou, Zhihua; Feng, Lei; Zhang, Shuzhen; Wang, Chendong; Chen, Guanyi; Du, Tao; Li, Yasong; Zuo, Jian

    2016-01-01

    Highlights: • Choose energy efficiency technology in office building to implement “nZEB”. • Simulate its energy consumption. • Study on the operational performance. • Optimize its running. - Abstract: There is no lack of studies on “net zero energy buildings” (“nZEB”). However, the vast majority of these studies focus on theories and simulation. The actual operational performance of “net zero energy building” during occupation has been largely overlooked by previous studies. This study aims to investigate the operational performance of net “zero energy buildings” via the case study of an office building in Tianjin, China. Using simulation, the energy consumption of the building at design phase was estimated and a solar photovoltaic (PV) system was selected. A whole year operation of the occupied building showed that energy consumption of the case building was much higher than the energy generated from the solar PV system. This was mainly due to three issues. Firstly, the equipment was different in terms of category, quantity and running time between operation and design stages, leading to considerable underestimate of energy consumption at the design stage. Secondly, the operational strategies need to be further improved in order to regulate users’ behaviors. Thirdly, the efficiency of solar PV system was substantially reduced due to poor atmospheric environment (i.e. haze weather). Therefore, during the design process of “net zero energy buildings”, it is imperative to ensure that the energy simulation accurately reflects how the building will actually operate once occupied. The research also revealed other barriers to the design and implementation of “nZEB” in China, such as extra efforts required for effective communicating the capacity of the HVAC design and systems to clients, and the increased cost of “nZEB” (e.g. solar PV system) particularly for public buildings. Finally, the solar radiation intensity of standard

  15. The US Department of Energy Nuclear Data and Low Energy Physics Programs: Aspects of current operational status and future direction

    Whetstone, S.L.; Meyer, R.A.

    1991-01-01

    The Nuclear Data and Low-Energy Programs are operated within the Division of Nuclear Physics of the US Department of Energy. The data program supports a range of activities including large scale data measurements, nuclear cross section modelling, and nuclear data compilation and dissemination. The US nuclear data needs and prospects for the future of this effort are currently being addressed and its present status is reviewed. Possibilities for the next generation nuclear data accessibility will be discussed and examples presented. The Low-Energy Nuclear Physics Program supports investigations into low-energy nuclear structure and neutrino physics. Among examples of the latter that are covered is the Sudbury Neutrino Observatory

  16. Energy Storage System Control Algorithm by Operating Target Power to Improve Energy Sustainability of Smart Home

    Byeongkwan Kang; Kyuhee Jang; Sounghoan Park; Myeong-in Choi; Sehyun Park

    2018-01-01

    As energy issues are emerging around the world, a variety of smart home technologies aimed at realizing zero energy houses are being introduced. Energy storage system (ESS) for smart home energy independence is increasingly gaining interest. However, limitations exist in that most of them are controlled according to time schedules or used in conjunction with photovoltaic (PV) generation systems. In consideration of load usage patterns and PV generation of smart home, this study proposes an ES...

  17. Radiant and convective heat transfer for flow of a transparent gas in a short tube with prescribed sinusoidal wall heat flux

    de Lemos, M.J.S.

    1982-01-01

    The present analysis accounts for radiant and convective heat transfer for a transparent fluid flowing in a short tube with prescribed wall heat flux. The heat flux distribution used was of sine shape with maximum at the middle of the tube. Such a solution is the approximate one for axial power in a nuclear reactor. The solutions for the tube wall and gas bulk temperatures were obtained by successive substitutions for the wall and gas balance energy equations. The results show a decrease of 30% for the maximum wall temperature using black surface (e = 1). In this same case, the increasing in the gas temperature shows a decrease of 58%

  18. Safe Energy Source in Battery-operated Toys for Children.

    Rossi, Alfredo; Vignola, Silvia; Nason, Francesca; Boschetti, Federica; Bramerio, Manuela; Bailini, Alessandro; Pinarello, Giordano

    2017-11-01

    Serious and even fatal consequences of disk batteries ingestion in children are well known. Among other applications, disk batteries are used to power small toys, from which they can be unexpectedly extracted and swallowed. We tested a new cell intended for little toys (green cell [GC]), after 6 and 12 hours of in vitro close contact with esophageal swine mucosa. The GC was compared with lithium and silver button batteries under the same experimental conditions. Tissues in contact with the GC did not show pH variations nor histological alterations after 6 and 12 hours. In such conditions, statistically significant differences were found between the GC and the lithium and silver batteries. So far, multidisciplinary medical effort has been driven to both emergency approach and subsequent operative strategies in children with ingested batteries. Our trial demonstrates the possibility to primarily prevent battery-induced damages by designing new-generation safe cells with no tissue toxicity to power little toys intended for children.

  19. Operating experience review - Ventilation systems at Department of Energy Facilities

    1994-05-01

    The Office of Special Projects (DP-35), formerly Office of Self-Assessment (DP-9), analyzed occurrences caused by problems with equipment and material and recommended the following systems for an in-depth study: (1) Selective Alpha Air Monitor (SAAM), (2) Emergency Diesel Generator, (3) Ventilation System, (4) Fire Alarm System. Further, DP-35 conducted an in-depth review of the problems associated with SAAM and with diesel generators, and made several recommendations. This study focusses on ventilation system. The intent was to determine the causes for the events related to these system that were reported in the Occurrence Reporting and Processing System (ORPS), to identify components that failed, and to provide technical information from the commercial and nuclear industries on the design, operation, maintenance, and surveillance related to the system and its components. From these data, sites can develop a comprehensive program of maintenance management, including surveillance, to avoid similar occurrences, and to be in compliance with the following DOE orders.

  20. Energy Storage in Power System Operation: The Power Nodes Modeling Framework

    Heussen, Kai; Koch, Stephan; Ulbig, Andreas

    2010-01-01

    for designing operation strategies for power systems based on ubiquitous energy storage, for example to buer non-dispatchable generation, as well as for the evaluation of the operational performance in terms of energy eciency, reliability and cost. After introducing the modeling approach and a categorization......In this paper, a novel concept for the description of energy storage in power systems with dispatchable and non-dispatchable generators and loads is presented. It is based on a system-perspective consideration of energy storage, generation and consumption. This means that grid-relevant aspects...

  1. Proposed continuous wave energy recovery operation of an XFEL

    J. Sekutowicz; S. A. Bogacz; D. Douglas; P. Kneisel; G. P. Williams; M. Ferrario; L. Serafini; I. Ben-Zvi; J. Rose; J. Smedley; T. Srinivasan-Rao; W.-D. Moeller; B. Petersen; D. Proch; S. Simrock; P. Colestock; J. B. Rosenzweig

    2004-01-01

    Commissioning of two large coherent light facilities at SLAC and DESY should begin in 2008 and in 2011 respectively. In this paper we look further into the future, hoping to answer, in a very preliminary way, two questions. First: ''What will the next generation of XFEL facilities look like?'' Believing that superconducting technology offers advantages such as high quality beams with highly populated bunches, the possibility of energy recovery and higher overall efficiency than warm technology, we focus this preliminary study on the superconducting option. From this belief the second question arises: ''What modifications in superconducting technology and in the machine design are needed, as compared to the present DESY XFEL, and what kind of R and D program should be proposed to arrive in the next few years at a technically feasible solution with even higher brilliance and increased overall conversion of AC power to photon beam power?'' In this paper we will very often refer to and profit from the DESY XFEL design, acknowledging its many technically innovative solutions

  2. Continuous wave energy recovery operation of an XFEL

    Jacek Sekutowicz; Bogacz, S. A.; Douglas, D.; Kneisel, Peter; Williams, G. P.; Ferrario, M.; Serafini, L.; Ben-Zvi, I.; Rose, J.; Srinivasan-Rao, T.; Mueller, W.-D.; Petersen, B.; Proch, D.; Simrock, S.; Colestock, P.; Rosenzweig, J. B.

    2003-01-01

    Commissioning of two large coherent light facilities at SLAC and DESY should begin in 2008 and in 2011 respectively. In this paper we look further into the future, hoping to answer, in a very preliminary way, two questions. First: ''What will the next generation of XFEL facilities look like?'' Believing that superconducting technology offers advantages such as high quality beams with highly populated bunches, the possibility of energy recovery and higher overall efficiency than warm technology, we focus this preliminary study on the superconducting option. From this belief the second question arises: ''What modifications in superconducting technology and in the machine design are needed, as compared to the present DESY XFEL, and what kind of R and D program should be proposed to arrive in the next few years at a technically feasible solution with even higher brilliance and increased overall conversion of AC power to photon beam power?'' In this paper we will very often refer to and profit from the DESY XFEL design, acknowledging its many technically innovative solutions

  3. Anomalous dimensions of heavy operators from magnon energies

    Koch, Robert de Mello; Tahiridimbisoa, Nirina Hasina; Mathwin, Christopher [National Institute for Theoretical Physics,School of Physics and Mandelstam Institute for Theoretical Physics, University of Witwatersrand,Wits, 2050 (South Africa)

    2016-03-22

    We study spin chains with boundaries that are dual to open strings suspended between systems of giant gravitons and dual giant gravitons. Motivated by a geometrical interpretation of the central charges of su(2|2), we propose a simple and minimal all loop expression that interpolates between the anomalous dimensions computed in the gauge theory and energies computed in the dual string theory. The discussion makes use of a description in terms of magnons, generalizing results for a single maximal giant graviton. The symmetries of the problem determine the structure of the magnon boundary reflection/scattering matrix up to a phase. We compute a reflection/scattering matrix element at weak coupling and verify that it is consistent with the answer determined by symmetry. We find the reflection/scattering matrix does not satisfy the boundary Yang-Baxter equation so that the boundary condition on the open spin chain spoils integrability. We also explain the interpretation of the double coset ansatz in the magnon language.

  4. Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

    NONE

    1997-12-31

    This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

  5. Present and projected future mean radiant temperature for three European cities

    Thorsson, Sofia; Rayner, David; Lindberg, Fredrik; Monteiro, Ana; Katzschner, Lutz; Lau, Kevin Ka-Lun; Campe, Sabrina; Katzschner, Antje; Konarska, Janina; Onomura, Shiho; Velho, Sara; Holmer, Björn

    2017-09-01

    Present-day and projected future changes in mean radiant temperature, T mrt in one northern, one mid-, and one southern European city (represented by Gothenburg, Frankfurt, and Porto), are presented, and the concept of hot spots is adopted. Air temperature, T a , increased in all cities by 2100, but changes in solar radiation due to changes in cloudiness counterbalanced or exacerbated the effects on T mrt. The number of days with high T mrt in Gothenburg was relatively unchanged at the end of the century (+1 day), whereas it more than doubled in Frankfurt and tripled in Porto. The use of street trees to reduce daytime radiant heat load was analyzed using hot spots to identify where trees could be most beneficial. Hot spots, although varying in intensity and frequency, were generally confined to near sunlit southeast-southwest facing walls, in northeast corner of courtyards, and in open spaces in all three cities. By adding trees in these spaces, the radiant heat load can be reduced, especially in spaces with no or few trees. A set of design principles for reducing the radiant heat load is outlined based on these findings and existing literature.

  6. Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

    NONE

    1996-12-31

    This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

  7. Applicability of meteor radiant determination methods depending on orbit type. I. High-eccentric orbits

    Svoren, J.; Neslusan, L.; Porubcan, V.

    1993-07-01

    It is evident that there is no uniform method of calculating meteor radiants which would yield reliable results for all types of cometary orbits. In the present paper an analysis of this problem is presented, together with recommended methods for various types of orbits. Some additional methods resulting from mathematical modelling are presented and discussed together with Porter's, Steel-Baggaley's and Hasegawa's methods. In order to be able to compare how suitable the application of the individual radiant determination methods is, it is necessary to determine the accuracy with which they approximate real meteor orbits. To verify the accuracy with which the orbit of a meteoroid with at least one node at 1 AU fits the original orbit of the parent body, we applied the Southworth-Hawkins D-criterion (Southworth, R.B., Hawkins, G.S.: 1963, Smithson. Contr. Astrophys 7, 261). D0.2 the fit is rather poor and the change of orbit unrealistic. The optimal methods with the smallest values of D for given types of orbits are shown in two series of six plots. The new method of rotation around the line of apsides we propose is very appropriate in the region of small inclinations. There is no doubt that Hasegawa's omega-adjustment method (Hasegawa, I.: 1990, Publ. Astron. Soc. Japan 42, 175) has the widest application. A comparison of the theoretical radiants with the observed radiants of seven known meteor showers is also presented.

  8. Theoretical Analysis of Interferometer Wave Front Tilt and Fringe Radiant Flux on a Rectangular Photodetector

    Franz Konstantin Fuss

    2013-09-01

    Full Text Available This paper is a theoretical analysis of mirror tilt in a Michelson interferometer and its effect on the radiant flux over the active area of a rectangular photodetector or image sensor pixel. It is relevant to sensor applications using homodyne interferometry where these opto-electronic devices are employed for partial fringe counting. Formulas are derived for radiant flux across the detector for variable location within the fringe pattern and with varying wave front angle. The results indicate that the flux is a damped sine function of the wave front angle, with a decay constant of the ratio of wavelength to detector width. The modulation amplitude of the dynamic fringe pattern reduces to zero at wave front angles that are an integer multiple of this ratio and the results show that the polarity of the radiant flux changes exclusively at these multiples. Varying tilt angle causes radiant flux oscillations under an envelope curve, the frequency of which is dependent on the location of the detector with the fringe pattern. It is also shown that a fringe count of zero can be obtained for specific photodetector locations and wave front angles where the combined effect of fringe contraction and fringe tilt can have equal and opposite effects. Fringe tilt as a result of a wave front angle of 0.05° can introduce a phase measurement difference of 16° between a photodetector/pixel located 20 mm and one located 100 mm from the optical origin.

  9. Experimental and numerical analysis of air and radiant cooling systems in offices

    Corgnati, S. P.; Perino, M.; Fracastoro, G. V.

    2009-01-01

    This paper analyses office cooling systems based on all air mixing ventilation systems alone or coupled with radiant ceiling panels. This last solution may be effectively applied to retrofit all air systems that are no longer able to maintain a suitable thermal comfort in the indoor environment, ...

  10. Integration of energy analytics and smart energy microgrid into mobile medicine operations for the 2012 Democratic National Convention.

    McCahill, Peter W; Noste, Erin E; Rossman, A J; Callaway, David W

    2014-12-01

    Disasters create major strain on energy infrastructure in affected communities. Advances in microgrid technology offer the potential to improve "off-grid" mobile disaster medical response capabilities beyond traditional diesel generation. The Carolinas Medical Center's mobile emergency medical unit (MED-1) Green Project (M1G) is a multi-phase project designed to demonstrate the benefits of integrating distributive generation (DG), high-efficiency batteries, and "smart" energy utilization in support of major out-of-hospital medical response operations. Carolinas MED-1 is a mobile medical facility composed of a fleet of vehicles and trailers that provides comprehensive medical care capacities to support disaster response and special-event operations. The M1G project partnered with local energy companies to deploy energy analytics and an energy microgrid in support of mobile clinical operations for the 2012 Democratic National Convention (DNC) in Charlotte, North Carolina (USA). Energy use data recorded throughout the DNC were analyzed to create energy utilization models that integrate advanced battery technology, solar photovoltaic (PV), and energy conservation measures (ECM) to improve future disaster response operations. The generators that supply power for MED-1 have a minimum loading ratio (MLR) of 30 kVA. This means that loads below 30 kW lead to diesel fuel consumption at the same rate as a 30 kW load. Data gathered from the two DNC training and support deployments showed the maximum load of MED-1 to be around 20 kW. This discrepancy in MLR versus actual load leads to significant energy waste. The lack of an energy storage system reduces generator efficiency and limits integration of alternative energy generation strategies. A storage system would also allow for alternative generation sources, such as PV, to be incorporated. Modeling with a 450 kWh battery bank and 13.5 kW PV array showed a 2-fold increase in potential deployment times using the same amount of

  11. Proposed energy conservation contingency plan: emergency restrictions on advertising lighting. Authorities, need, rationale, and operation

    1977-04-01

    The emergency restrictions on advertising lighting proposed in Energy Conservation Contingency Plan No. 5 of 1977 are presented. A statement is given on the need for rationale and operation of the Contingency Plan.

  12. Energy distribution system operator in interaction with social actors : Three cases

    Steenhuisen, B.M.; Veeneman, W.W.; Van Doorn, L.; Van Breen, H.

    2012-01-01

    A publicly owned Dutch energy distribution system operator (DSO) interacts during local infrastructure projects with its direct stakeholders to maximize utility in the public interest. These projects are about replacing, relocating, removing or reconstructing parts of the gas and electricity

  13. Optimal Design and Operation Management of Battery-Based Energy Storage Systems (BESS) in Microgrids

    Anvari-Moghaddam, Amjad; Dulout, Jeremy; Alonso, Corinne

    2017-01-01

    of energy storage units requires certain performance measures and constraints, which has to be well considered in design phase and embedded in control and management strategies. This chapter mainly focuses on these aspects and provides a general framework for optimal design and operation management......-scale integration of renewables into the grid environment. Energy storage options can also be used for economic operation of energy systems to cut down system’s operating cost. By utilizing ESSs, it is very possible to store energy in off-peak hours with lower cost and energize the grid during peak load intervals...... at supply/demand side which is helpful for load levelling or peak shaving purposes. Last but not least, ESSs can provide frequency regulation services in offgrid locations where there is a strong need to meet the power balance in different operating conditions. Each of the abovementioned applications...

  14. Title V Operating Permit: XTO Energy, Inc. - River Bend Dehydration Site

    Initial Title V Operating Permit (Permit Number: V-UO-000026-2011.00) and the Administrative Permit Record for the XTO Energy, Inc., River Bend Dehydration Site, located on the Uintah and Ouray Indian Reservation.

  15. Compilation of Energy Efficient Concepts in Advanced Aircraft Design and Operations. Volume 1. Technical report

    Clyman, Milton

    1980-01-01

    .... The search addressed the technologies necessary to support next generation (IOC 1990+) air vehicle design and operation concepts that will reduce the requirement for natural petroleum-derived energy...

  16. Construction of two-dimensional Schrodinger operator with given scattering amplitude at fixed energy

    Novikov, R.G.

    1986-01-01

    The classical necessary properties of the scattering amplitude (reciprocity and unitarity) are, provided its L 2 norm is small, sufficient for the existence of a two-dimensional Schrodinger operator with the given scattering amplitude at fixed energy

  17. A multi evaporator desalination system operated with thermocline energy for future sustainability

    Shahzad, Muhammad Wakil; Burhan, Muhammad; Ghaffour, NorEddine; Ng, Kim Choon

    2017-01-01

    ) of desalination is at 828. Despite slightly better UPRs for the RO plants, all practical desalination plants available, hitherto, operate at only less than 12% of the TL, rendering them highly energy intensive and unsustainable for future sustainability. More

  18. Energy Management Strategy Based on Multiple Operating States for a Photovoltaic/Fuel Cell/Energy Storage DC Microgrid

    Ying Han

    2017-01-01

    Full Text Available It is a great challenge for DC microgrids with stochastic renewable sources and volatility loads to achieve better operation performance. This study proposes an energy management strategy based on multiple operating states for a DC microgrid, which is comprised of a photovoltaic (PV array, a proton exchange membrane fuel cell (PEMFC system, and a battery bank. This proposed strategy can share the power properly and keep the bus voltage steady under different operating states (the state of charge (SOC of the battery bank, loading conditions, and PV array output power. In addition, a microgrids test platform is established. In order to verify the effectiveness of the proposed energy management strategy, the strategy is implemented in a hardware system and experimentally tested under different operating states. The experimental results illustrate the good performance of the proposed control strategy for the DC microgrid under different scenarios of power generation and load demand.

  19. High energy bursts from a solid state laser operated in the heat capacity limited regime

    Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

    1996-06-11

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

  20. Characteristics of infrared thermometers manufactured in Japan and calibration methods for sky radiant emittance

    Wang, X.; Horiguchi, I.; Machimura, T.

    1993-01-01

    Infrared thermometers to measure surface temperature have been increasingly adopted in recent years. The characteristics of the IR thermometer, however, are not well known.IR thermometers manufactured in Japan systematically adjust for ambient radiation based on the internal temperature of the thermometer. If, therefore, there is a large difference between the internal temperature of the IR thermometer and the apparent temperature associated with the surrounding radiation, a large error will be induced into the measured surface temperature.The purpose of our research was to determine the characteristics and measurement errors of IR thermometers. Experiments were performed with regard to the following items: (1) Measurement errors related to the internal temperature of the IR thermometer. (2) Linearity of the output signal of the IR thermometer. (3) Response of the output signal to changes in the emissivity setting. (4) Effect of sky radiant emittance on the measured surface temperature. (5) Calibration method for the terrestrial surface.The following is a summary of the results: Measurement error is affected by the internal temperature of the IR thermometer. Measurement accuracy is improved with a controlled internal temperature of 20-30°C. The measurement error becomes larger at emissivity settings under 0.7.The measurement error outdoors was not proportional to the downward longwave radiation, but to the sky radiant temperature measured by the IR thermometer. Calibration for sky radiant emittance was improved by using the difference between sky radiant temperature and air temperature.When the surface temperature measured by the infrared thermometer is plotted against the surface temperature measured by thermocouple, the sky radiant emittance error is obtained from the Y intercept. Additionally, the difference between true temperature and output of the IR thermometer for a reference plate was compared to that obtained for vegetation, and the RMS obtained was

  1. The relationship between radiant heat, air temperature and thermal comfort at rest and exercise.

    Guéritée, Julien; Tipton, Michael J

    2015-02-01

    The aims of the present work were to investigate the relationships between radiant heat load, air velocity and body temperatures with or without coincidental exercise to determine the physiological mechanisms that drive thermal comfort and thermoregulatory behaviour. Seven male volunteers wearing swimming trunks in 18°C, 22°C or 26°C air were exposed to increasing air velocities up to 3 m s(-1) and self-adjusted the intensity of the direct radiant heat received on the front of the body to just maintain overall thermal comfort, at rest or when cycling (60 W, 60 rpm). During the 30 min of the experiments, skin and rectal temperatures were continuously recorded. We hypothesized that mean body temperature should be maintained stable and the intensity of the radiant heat and the mean skin temperatures would be lower when cycling. In all conditions, mean body temperature was lower when facing winds of 3 m s(-1) than during the first 5 min, without wind. When facing winds, in all but the 26°C air, the radiant heat was statistically higher at rest than when exercising. In 26°C air mean skin temperature was lower at rest than when exercising. No other significant difference was observed. In all air temperatures, high correlation coefficients were observed between the air velocity and the radiant heat load. Other factors that we did not measure may have contributed to the constant overall thermal comfort status despite dropping mean skin and body temperatures. It is suggested that the allowance to behaviourally adjust the thermal environment increases the tolerance of cold discomfort. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Energy and operation management of a microgrid using particle swarm optimization

    Radosavljević, Jordan; Jevtić, Miroljub; Klimenta, Dardan

    2016-05-01

    This article presents an efficient algorithm based on particle swarm optimization (PSO) for energy and operation management (EOM) of a microgrid including different distributed generation units and energy storage devices. The proposed approach employs PSO to minimize the total energy and operating cost of the microgrid via optimal adjustment of the control variables of the EOM, while satisfying various operating constraints. Owing to the stochastic nature of energy produced from renewable sources, i.e. wind turbines and photovoltaic systems, as well as load uncertainties and market prices, a probabilistic approach in the EOM is introduced. The proposed method is examined and tested on a typical grid-connected microgrid including fuel cell, gas-fired microturbine, wind turbine, photovoltaic and energy storage devices. The obtained results prove the efficiency of the proposed approach to solve the EOM of the microgrids.

  3. Determination of the Cascade Reservoir Operation for Optimal Firm-Energy Using Genetic Algorithms

    Azmeri

    2013-08-01

    Full Text Available Indonesia today face a new paradigm in water management where aim to apply integrated water resources management has become unavoidable task in purpose of achieving greater level of effectiveness and efficiency. On of most interesting case study is the case of Citarum river, one of the most potential river for water supply in West Java, Indonesia. Alongside the river, Saguling, Cirata and Djuanda Reservoirs had been constructed in series/cascade. Saguling and Cirata reservoirs are particularly operated for hydroelectric power and Djuanda is multipurpose reservoir mainly operated for irrigation and contribute domestic water supply for Jakarta (capital city of Indonesia. Basically all reservoirs are relying on same resources, therefore this condition has considered addressing management and operational problem. Therefore, an approach toward new management and operation system are urgently required in order to achieve the effective and efficient output and to avoid conflicts of water used. This study aims to obtain energy production from Citarum Cascade Reservoir System using Genetic Algorithms optimization with the objective function to maximize firm-energy. Firm-energy is the minimum energy requirements must be available in a certain time period. Then, the result obtained by using the energy produced by GA is compared to the conventional searching technique of Non-Linier Programming (NLP. The GA derived operating curves reveal the higher energy and firm-energy than NLP model

  4. Estimating energy requirement in cashew (Anacardium occidentale L.) nut processing operations

    Jekayinfa, S.O. [Department of Agricultural Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Oyo State (Nigeria); Bamgboye, A.I. [Department of Agricultural Engineering, University of Ibadan, Ibadan (Nigeria)

    2006-07-15

    This work deals with a study on estimation of energy consumption in eight readily defined unit operations of cashew nut processing. Data for analysis were collected from nine cashew nut mills stratified into small, medium and large categories to represent different mechanization levels. Series of equations were developed to easily compute requirements of electricity, fuel and labour for each of the unit operations. The computation of energy use was done using spreadsheet program on Microsoft Excel. The results of application test of the equations show that the total energy intensity in the cashew nut mills varied between 0.21 and 1.161MJ/kg. Electrical energy intensity varied between 0.0052 and 0.029MJ/kg, while thermal energy intensity varied from 0.085 to 1.064MJ/kg. The two identified energy intensive operations in cashew nut processing are cashew nut drying and cashew nut roasting, altogether accounting for over 85% of the total energy consumption in all the three mill categories. Thermal energy, obtained from diesel fuel, represented about 90% of the unit energy cost for cashew nut processing. The developed equations have therefore proven to be a useful tool for carrying out budgeting, forecasting energy requirements and planning plant expansion. (author)

  5. Simulation of nuclear plant operation into a stochastic energy production model

    Pacheco, R.L.

    1983-04-01

    A simulation model of nuclear plant operation is developed to fit into a stochastic energy production model. In order to improve the stochastic model used, and also reduce its computational time burdened by the aggregation of the model of nuclear plant operation, a study of tail truncation of the unsupplied demand distribution function has been performed. (E.G.) [pt

  6. Impacts of ramping inflexibility of conventional generators on strategic operation of energy storage facilities

    Nasrolahpour, Ehsan; Kazempour, Jalal; Zareipour, Hamidreza

    2016-01-01

    This paper proposes an approach to assist a pricemaker merchant energy storage facility in making its optimal operation decisions. The facility operates in a pool-based electricity market, where the ramping capability of other resources is limited. Also, wind power resources exist in the system...

  7. Operating conditions of batteries in off-grid renewable energy systems

    Svoboda, V.; Wenzl, H.; Kaiser, R.

    2007-01-01

    for batteries. Categories are defined in such a way that batteries belonging to the same category are subjected to similar operating conditions and a similar combination of stress factors. The results provide a comprehensive overview of battery operating conditions in existing off-grid renewable energy systems...

  8. 75 FR 16524 - FirstEnergy Nuclear Operating Company, Perry Nuclear Power Plant; Exemption

    2010-04-01

    ... Company, Perry Nuclear Power Plant; Exemption 1.0 Background FirstEnergy Nuclear Operating Company (FENOC... the Perry Nuclear Power Plant, Unit 1 (PNPP). The license provides, among other things, that the... date for all operating nuclear power plants, but noted that the Commission's regulations provide...

  9. Coordinated Operation of the Electricity and Natural Gas Systems with Bi-directional Energy Conversion

    Zeng, Qing; Zhang, Baohua; Fang, Jiakun

    2017-01-01

    A coordinated operation of the natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables. This work focuses on the unified optimal operation of the integrated natural gas and electricity system considering the network...

  10. Energy Profile and Perspectives on Northeast Asian Energy Co-operation of North Korea

    NONE

    2001-06-01

    Energy policy of North Korea is basically based on the 'Principle of Self-reliance'. Throughout the active development of domestic energy sources, North Korea try to maximize the energy self-reliance as well as to minimize the outflow of currency for the import of energy. But, the 'Principle of Self-reliance' of energy sector brought about the excess dependency on coal and hydro, and eventually causes the contraction of oil and natural gas consumption. This kind of adverse reaction of the 'Principle of Self-reliance' is the major reason of overall weakness of national-wide economic system. It is not known actually what kinds of perspectives North Korea has on the Northeast Asian energy cooperation. But, it can be said that Northeast Asian energy cooperation can be the best chance for North Korea to solve current energy crisis and to transfer the economic system to capitalism for the recovery of national economy. 19 refs., 4 figs., 9 tabs.

  11. Carbon flow electrodes for continuous operation of capacitive deionization and capacitive mixing energy generation

    Porada, S.; Hamelers, H.V.M.; Bryjak, M.; Presser, V.; Biesheuvel, P.M.; Weingarth, D.

    2014-01-01

    Capacitive technologies, such as capacitive deionization and energy harvesting based on mixing energy (“capmix” and “CO2 energy”), are characterized by intermittent operation: phases of ion electrosorption from the water are followed by system regeneration. From a system application point of view,

  12. Impact of Fluctuating Energy Prices on the Operation Strategy of a Trigeneration System

    Dražen Balić

    2015-09-01

    The optimization method is based on two criteria – energy and economic criterion, which were applied hierarchically. Therefore, two optimal operation strategies are introduced. A mixed integer non-linear programming model provides energy and cost savings up to 32% and 28% respectively in comparison with conventional system. In addition, optimal capacity of trigeneration system is explored.

  13. 76 FR 56242 - Duke Energy Carolinas, LLC; Southern Nuclear Operating Company; Establishment of Atomic Safety...

    2011-09-12

    ... NUCLEAR REGULATORY COMMISSION [Docket Nos. 52-018-COL, 52-019-COL, 52-025-COL, 52-026-COL; ASLBP No. 11-913-01-COL-BD01] Duke Energy Carolinas, LLC; Southern Nuclear Operating Company; Establishment... following captioned cases: Duke Energy Carolinas, LLC, (William States Lee III Nuclear Station, Units 1 and...

  14. A two-stage stochastic programming approach for operating multi-energy systems

    Zeng, Qing; Fang, Jiakun; Chen, Zhe

    2017-01-01

    This paper provides a two-stage stochastic programming approach for joint operating multi-energy systems under uncertainty. Simulation is carried out in a test system to demonstrate the feasibility and efficiency of the proposed approach. The test energy system includes a gas subsystem with a gas...

  15. Coordinated operation of a neighborhood of smart households comprising electric vehicles, energy storage and distributed generation

    Paterakis, N.G.; Erdinc, O.; Pappi, I.N.; Bakirtzis, A.G.; Catalao, J.P.S.

    2016-01-01

    In this paper, the optimal operation of a neighborhood of smart households in terms of minimizing the total energy procurement cost is analyzed. Each household may comprise several assets such as electric vehicles, controllable appliances, energy storage and distributed generation. Bi-directional

  16. Reducing the operational energy demand in buildings using building information modeling tools and sustainability approaches

    Mojtaba Valinejad Shoubi

    2015-03-01

    Full Text Available A sustainable building is constructed of materials that could decrease environmental impacts, such as energy usage, during the lifecycle of the building. Building Information Modeling (BIM has been identified as an effective tool for building performance analysis virtually in the design stage. The main aims of this study were to assess various combinations of materials using BIM and identify alternative, sustainable solutions to reduce operational energy consumption. The amount of energy consumed by a double story bungalow house in Johor, Malaysia, and assessments of alternative material configurations to determine the best energy performance were evaluated by using Revit Architecture 2012 and Autodesk Ecotect Analysis software to show which of the materials helped in reducing the operational energy use of the building to the greatest extent throughout its annual life cycle. At the end, some alternative, sustainable designs in terms of energy savings have been suggested.

  17. Territorial energy operators. The builders of an energetic and territorial autonomy

    Regnier, Yannick; Durand, Lucas; Arnaud, Baptiste; Rebelle, Bruno; Bailleul, Esther; Causse, Laurent; Cauvin, Frederick; Claustre, Raphael; Collin, Lucie; Ferrari, Albert; Julien, Emmanuel; Flye Sainte Marie, Luc; Hennion, Anne-Sophie; Leclerq, Michel; Le Page, Delphine; Le Quellenec, Johan; Marillier, Frederic; Martin, Florence; Moncorge, Sophie; Mottl, Karin; Rynikiewicz, Christophe; Ribardiere Le May, Elodie; Stegen, Eva; Robillard, Julien

    2017-06-01

    As the recent law on energy transition defined a legal framework which allowed the action of local authorities in the field of energy, and resulted in the creation of local or territorial energy utilities by these authorities or other actors, this report proposes a presentation of examples of territorial energy utilities or operators. These examples are chosen in different French towns, district or regions (Vienne, Montpellier, Lannion, Pays de Vilaine, Lot, Ile-de-France, Rhone-Alpes) but also in Germany and Austria. Before presenting these experiments, the authors describe and discuss the French legal framework of territorial energy transition. They describe the territorial energy operator as a factor of emergence of an energetic and territorial autonomy

  18. Design, Operation, and Controlled-Island Operation of the U.S. Department of Energy Solar Decathlon 2013 Microgrid

    Kurnik, C. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Butt, R. S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Metzger, I. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lavrova, O. [Univ. of New Mexico, Albuquerque, NM (United States); Patibandla, S. [Univ. of New Mexico, Albuquerque, NM (United States); Wagner, V. [Schneider Electric, Knoxville, TN (United States); Frankosky, M. [Schneider Electric, Knoxville, TN (United States); Wiegand, G. [MicroPlanet, Inc., Woodinville, WA (United States)

    2015-04-22

    This document reports on the design and operation of a high-capacity and high-penetration-ratio microgrid, which consists of 19 photovoltaic-powered residential houses designed by collegiate teams as part of their participation in the U.S. Department of Energy Solar Decathlon 2013. The microgrid was interconnected with the local utility, and resulting net-power and power-quality events were recorded in high detail (1-minute data sampling or better). Also, a controlled-island operation test was conducted to evaluate the microgrid response to additional events such as increased loads (e.g., from electric vehicles) and bypassing of voltage regulators. This temporary ground-laid microgrid was stable under nominal and island-operation conditions; adverse weather and loads did not lead to power-quality degradation.

  19. United States Department of Energy Nevada Operations Office Environmental Compliance Handbook. Third edition

    1998-03-01

    The Environment, Safety and Health Division (ESHD) of the Nevada Operations Office has prepared this Environmental Compliance Handbook for all users of the Nevada Test Site (NTS) and other US Department of Energy, Nevada Operations Office (DOE/NV) facilities. The Handbook gives an overview of the important environmental laws and regulations that apply to the activities conducted by the Nevada Operations Office and other users of DOE/NV facilities in Nevada

  20. Transactive control: a framework for operating power systems characterized by high penetration of distributed energy resources

    Hu, Junjie; Yang, Guangya; Kok, Koen

    2016-01-01

    The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level......, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized...

  1. United States Department of Energy Nevada Operations Office Environmental Compliance Handbook. Third edition

    NONE

    1998-03-01

    The Environment, Safety & Health Division (ESHD) of the Nevada Operations Office has prepared this Environmental Compliance Handbook for all users of the Nevada Test Site (NTS) and other US Department of Energy, Nevada Operations Office (DOE/NV) facilities. The Handbook gives an overview of the important environmental laws and regulations that apply to the activities conducted by the Nevada Operations Office and other users of DOE/NV facilities in Nevada.

  2. Matrix elements of vibration kinetic energy operator of tetrahedral molecules in non-orthogonal-dependent coordinates

    Protasevich, Alexander E.; Nikitin, Andrei V.

    2018-01-01

    In this work, we propose an algorithm for calculating the matrix elements of the kinetic energy operator for tetrahedral molecules. This algorithm uses the dependent six-angle coordinates (6A) and takes into account the full symmetry of molecules. Unlike A.V. Nikitin, M. Rey, and Vl. G. Tyuterev who operate with the kinetic energy operator only in Radau orthogonal coordinates, we consider a general case. The matrix elements are shown to be a sum of products of one-dimensional integrals.

  3. Operating experience review -- Conduct of operations at Department of Energy facilities

    1994-08-01

    This research examined human error related occurrences, reported in the ORPS database, for the purpose of identifying weaknesses in the implementation of the guidance regarding the Conduct of Operations contained in DOE 5480.19. Specifically, this research examined three separate samples of occurrence reports from Defense Program facilities, which cited human error as a direct or contributing cause. These reports were evaluated using a coding scheme which incorporated the guidelines present in 5480.19, as well as a number of generic human factors concerns. The second chapter of this report summarizes the coding scheme which was used to evaluate the occurrence reports. Since the coding scheme is quite lengthy, only the parts of the scheme needed to make the remainder of the report clear are included in this chapter. Details on the development and content of the coding scheme are reported in Appendices A, B, and C. Chapter 3 presents the analysis of three different data sets. This chapter demonstrates that similar results were obtained across different data sets, collected at different points in time, and coded by different raters. The implications of the results obtained in Chapter 3 are discussed in Chapter 4. This chapter makes a number of suggestions for reducing the problems found in the occurrence reports. Chapter 5 applies the methodology that has been developed in this report to two facilities at Los Alamos National Laboratory. Finally, Chapter 6 reiterates the major findings of this report. Several additional analyses appear in appendices at the end of this report

  4. Operation and sizing of energy storage for wind power plants in a market system

    Korpaas, M.; Holen, A.T.

    2003-01-01

    This paper presents a method for the scheduling and operation of energy storage for wind power plants in electricity markets. A dynamic programming algorithm is employed to determine the optimal energy exchange with the market for a specified scheduling period, taking into account transmission constraints. During operation, the energy storage is used to smooth variations in wind power production in order to follow the scheduling plan. The method is suitable for any type of energy storage and is also useful for other intermittent energy resources than wind. An application of the method to a case study is also presented, where the impact of energy storage sizing and wind forecasting accuracy on system operation and economics are emphasized. Simulation results show that energy storage makes it possible for owners of wind power plants to take advantage of variations in the spot price, by thus increasing the value of wind power in electricity markets. With present price estimates, energy storage devices such as reversible fuel cells are likely to be a more expensive alternative than grid expansions for the siting of wind farms in weak networks. However, for areas where grid expansions lead to unwanted interference with the local environment, energy storage should be considered as a reasonable way to increase the penetration of wind power. (author)

  5. Optimal operation strategy of battery energy storage system to real-time electricity price in Denmark

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    markets in some ways, is chosen as the studied power system in this paper. Two kinds of BESS, based on polysulfide-bromine (PSB) and vanadium redox (VRB) battery technologies, are studies in the paper. Simulation results show, that the proposed optimal operation strategy is an effective measure to achieve......Since the hourly spot market price is available one day ahead, the price could be transferred to the consumers and they may have some motivations to install an energy storage system in order to save their energy costs. This paper presents an optimal operation strategy for a battery energy storage...

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

    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...

  7. Operation Modeling of Power Systems Integrated with Large-Scale New Energy Power Sources

    Hui Li

    2016-10-01

    Full Text Available In the most current methods of probabilistic power system production simulation, the output characteristics of new energy power generation (NEPG has not been comprehensively considered. In this paper, the power output characteristics of wind power generation and photovoltaic power generation are firstly analyzed based on statistical methods according to their historical operating data. Then the characteristic indexes and the filtering principle of the NEPG historical output scenarios are introduced with the confidence level, and the calculation model of NEPG’s credible capacity is proposed. Based on this, taking the minimum production costs or the best energy-saving and emission-reduction effect as the optimization objective, the power system operation model with large-scale integration of new energy power generation (NEPG is established considering the power balance, the electricity balance and the peak balance. Besides, the constraints of the operating characteristics of different power generation types, the maintenance schedule, the load reservation, the emergency reservation, the water abandonment and the transmitting capacity between different areas are also considered. With the proposed power system operation model, the operation simulations are carried out based on the actual Northwest power grid of China, which resolves the new energy power accommodations considering different system operating conditions. The simulation results well verify the validity of the proposed power system operation model in the accommodation analysis for the power system which is penetrated with large scale NEPG.

  8. Department of Defense Operational Energy Strategy: A Content Analysis of Energy Literature from 1973-2014

    2014-03-27

    energy labels among others. These Corporate Average Fuel Economy ( CAFE ) standards were an initial means in improving the fuel efficiency of vehicles...Independence and Security Act of 2007 as a way to address the country’s energy security concerns (Scofield, 2009). Two key provisions enacted are the CAFE ...truth is that, according to a 2006 JASON report, “DoD is not a sufficiently large customer to drive the domestic market for demand and consumption of

  9. Cost, energy use and GHG emissions for forest biomass harvesting operations

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang; Yu, Chunxia

    2016-01-01

    For forest-based biomass to become a significant contribution to the United States' energy portfolio, harvesting operations must be physically feasible and economically viable. An assessment of cost, energy and greenhouse gas (GHG) emissions of forest biomass harvesting was conducted. The assessment differentiates harvesting systems by cut-to-length and whole tree; harvest types of 30%, 70%, and 100% cut; and forest types of hardwoods, softwoods, mixed hardwood/softwood, and softwood plantations. Harvesting cost models were developed for economic assessment and life cycle energy and emission assessment was applied to calculate energy and emissions for different harvesting scenarios, considering material and energy inputs (machinery, diesel, etc.) and outputs (GHG emissions) for each harvesting process (felling, forwarding/skidding, etc.). The developed harvesting cost models and the life cycle energy and emission assessment method were applied in Michigan, U.S. using information collected from different sources. A sensitivity analysis was performed for selected input variables for the harvesting operations in order to explore their relative importance. The results indicated that productivity had the largest impact on harvesting cost followed by machinery purchase price, yearly scheduled hours, and expected utilization. Productivity and fuel use, as well as fuel factors, are the most influential environmental impacts of harvesting operations. - Highlights: • Life cycle energy and emissions for forest biomass harvesting operations. • Harvesting cost models were developed for economic assessment. • Productivity had the largest impact on harvesting cost. • Fuel use contributes the most emissions while lubricants contribute the least.

  10. Energy saving by using natural energy from the shallow ground depths - many years operating results

    Besler, Maciej; Skrzycki, Maciej; Cepiński, Wojciech

    2017-11-01

    We pay back more and more larger attention on solutions which saving energy produced from conventional fuels. This is possible to obtainment in significant quantities in fields in which use up the large quantities of energy. The formation the microclimate of interiors is an example of such situation. Especially in the case air conditioning, heating and mechanical ventilation. There is, however, a possibility of energy saving as well as considerable reducing the pollution coming from combustion of raw materials by utilising the natural renewable energy from the shallow ground. In the paper the results gained during several year of continuous measurement on the exchanger were presented. In summer periods an air cooling occurs 10-12 K, e. g. from +30 °C to +20 °C. In winter on the other hand, a preparatory preheating of the air is possible, e.g. from-18°C to about ± 0°C. It is then possible to obtain for the air conditioning system the total energy needed for cooling purposes at the summer periods, or up to 50% of the ventilation heat energy in winter picks.

  11. Energy saving by using natural energy from the shallow ground depths – many years operating results

    Besler Maciej

    2017-01-01

    Full Text Available We pay back more and more larger attention on solutions which saving energy produced from conventional fuels. This is possible to obtainment in significant quantities in fields in which use up the large quantities of energy. The formation the microclimate of interiors is an example of such situation. Especially in the case air conditioning, heating and mechanical ventilation. There is, however, a possibility of energy saving as well as considerable reducing the pollution coming from combustion of raw materials by utilising the natural renewable energy from the shallow ground. In the paper the results gained during several year of continuous measurement on the exchanger were presented. In summer periods an air cooling occurs 10–12 K, e. g. from +30 °C to +20 °C. In winter on the other hand, a preparatory preheating of the air is possible, e.g. from-18°C to about ± 0°C. It is then possible to obtain for the air conditioning system the total energy needed for cooling purposes at the summer periods, or up to 50% of the ventilation heat energy in winter picks.

  12. Design, analysis, operation, and advanced control of hybrid renewable energy systems

    Whiteman, Zachary S.

    Because using non-renewable energy systems (e.g., coal-powered co-generation power plants) to generate electricity is an unsustainable, environmentally hazardous practice, it is important to develop cost-effective and reliable renewable energy systems, such as photovoltaics (PVs), wind turbines (WTs), and fuel cells (FCs). Non-renewable energy systems, however, are currently less expensive than individual renewable energy systems (IRESs). Furthermore, IRESs based on intermittent natural resources (e.g., solar irradiance and wind) are incapable of meeting continuous energy demands. Such shortcomings can be mitigated by judiciously combining two or more complementary IRESs to form a hybrid renewable energy system (HRES). Although previous research efforts focused on the design, operation, and control of HRESs has proven useful, no prior HRES research endeavor has taken a systematic and comprehensive approach towards establishing guidelines by which HRESs should be designed, operated, and controlled. The overall goal of this dissertation, therefore, is to establish the principles governing the design, operation, and control of HRESs resulting in cost-effective and reliable energy solutions for stationary and mobile applications. To achieve this goal, we developed and demonstrated four separate HRES principles. Rational selection of HRES type: HRES components and their sizes should be rationally selected using knowledge of component costs, availability of renewable energy resources, and expected power demands of the application. HRES design: by default, the components of a HRES should be arranged in parallel for increased efficiency and reliability. However, a series HRES design may be preferred depending on the operational considerations of the HRES components. HRES control strategy selection: the choice of HRES control strategy depends on the dynamics of HRES components, their operational considerations, and the practical limitations of the HRES end-use. HRES data

  13. Operation of a wind turbine-flywheel energy storage system under conditions of stochastic change of wind energy.

    Tomczewski, Andrzej

    2014-01-01

    The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS) operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author's opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level.

  14. Energy of surface states for 3D magnetic Schrödinger operators

    Nasrallah, Marwa

    In this dissertation, we study the Schrödinger operator with magnetic field in a three dimensional domain with compact smooth boundary. Functions in the domain of the operator satisfy (magnetic) Neumann condition on the boundary. The operator depends on the semi-classical parameter....... As this parameter becomes small, certain eigenfunctions of the operator are localized near the boundary of the domain, hence they will be called surface states. The main result of this dissertation is the calculation of the leading order terms of the energy and the number of surface states when the semi-classical...

  15. Analysis of electrical energy consumers operation in the heating plant with proposal of energy savings measures

    Nikolić Aleksandar

    2016-01-01

    Full Text Available The results of power quality measurements, obtained during an energy audit in the heating plant Vreoci in the Electric Power System of Serbia, are presented in the paper. Two steam boilers, rated at 120MW each, are installed in this heating plant, using coal as a fuel. The energy audit encompassed the measurements of the complete set of parameters needed to determine the thermal efficacy of boilers and the entire heating plant. Based on the measurement results, several technical measures for improving energy efficiency of the plant are proposed. The measures evaluated in the paper should contribute to the reduction of fossil fuel usage and CO2 emissions, thereby resulting in a significant impact in both financial and ecological areas.

  16. A genetic algorithm solution for the operation of green LTE networks with energy and environment considerations

    Ghazzai, Hakim

    2012-01-01

    The Base Station (BS) sleeping strategy has become a well-known technique to achieve energy savings in cellular networks by switching off redundant BSs mainly for lightly loaded networks. Besides, the exploitation of renewable energies, as additional power sources in smart grids, becomes a real challenge to network operators to reduce power costs. In this paper, we propose a method based on genetic algorithms that decreases the energy consumption of a Long-Term Evolution (LTE) cellular network by not only shutting down underutilized BSs but also by optimizing the amounts of energy procured from the smart grid without affecting the desired Quality of Service. © 2012 Springer-Verlag.

  17. On thermoeconomics of energy systems at variable load conditions: Integrated optimization of plant design and operation

    Piacentino, A.; Cardona, F.

    2007-01-01

    Thermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems, its different methodologies allowing solution of problems in the fields of cost accounting, plant design optimisation and diagnostic of malfunctions. However, the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasi-steady operation, but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper, the fundamentals of thermoeconomics for systems operated at variable load are discussed, examining the cost formation process and, separately, the cost fractions related to capital depreciation (which require additional distinctions with respect to plants in steady operation) and to exergy consumption. The relevant effects of the efficiency penalty due to off design operation on the exergetic cost of internal flows are also examined. An original algorithm is proposed for the integrated optimization of plant design and operation based on an analytical solution by the Lagrange multipliers method and on a multi-objective decision function, expressed either in terms of net cash flow or primary energy saving. The method is suitable for application in complex energy systems, such as 'facilities of components of a same product' connected to external networks for power or heat distribution. For demonstrative purposes, the proposed thermoeconomically aided optimization is performed for a grid connected trigeneration system to be installed in a large hotel

  18. Super-Radiant Free Electron Laser Measurement and Detection

    2013-09-01

    Optical Society of America, vol. 48, no. 8, pp. 531–533, Aug. 1958. [17] W. T. Welford and R. Winston, The Optics of Nonimaging Concentrators: Light...they can operate at the high average power with excellent optical beam quality that is needed in many military applications. A current project between...still maintaining reasonable size cavities, which may reduce power requirements for the cryoplant. This thesis will discuss variety of optical

  19. A flexible model for economic operational management of grid battery energy storage

    Fares, Robert L.; Webber, Michael E.

    2014-01-01

    To connect energy storage operational planning with real-time battery control, this paper integrates a dynamic battery model with an optimization program. First, we transform a behavioral circuit model designed to describe a variety of battery chemistries into a set of coupled nonlinear differential equations. Then, we discretize the differential equations to integrate the battery model with a GAMS (General Algebraic Modeling System) optimization program, which decides when the battery should charge and discharge to maximize its operating revenue. We demonstrate the capabilities of our model by applying it to lithium-ion (Li-ion) energy storage operating in Texas' restructured electricity market. By simulating 11 years of operation, we find that our model can robustly compute an optimal charge-discharge schedule that maximizes daily operating revenue without violating a battery's operating constraints. Furthermore, our results show there is significant variation in potential operating revenue from one day to the next. The revenue potential of Li-ion storage varies from approximately $0–1800/MWh of energy discharged, depending on the volatility of wholesale electricity prices during an operating day. Thus, it is important to consider the material degradation-related “cost” of performing a charge-discharge cycle in battery operational management, so that the battery only operates when revenue exceeds cost. - Highlights: • A flexible, dynamic battery model is integrated with an optimization program. • Electricity price data is used to simulate 11 years of Li-ion operation on the grid. • The optimization program robustly computes an optimal charge-discharge schedule. • Variation in daily Li-ion battery revenue potential from 2002 to 2012 is shown. • We find it is important to consider the cost of a grid duty cycle

  20. Freeform Lens Design for Scattering Data with General Radiant Fields

    Gutiérrez, Cristian E.; Sabra, Ahmad

    2018-05-01

    We show the existence of a lens, when its lower face is given, such that it refracts radiation emanating from a planar source, with a given field of directions, into the far field that preserves a given distribution of energies. Conditions are shown under which the lens obtained is physically realizable. It is shown that the upper face of the lens satisfies a pde of Monge-Ampère type.

  1. Super-radiant Smith–Purcell radiation from periodic line charges

    Li, D.; Hangyo, M.; Tsunawaki, Y.; Yang, Z.; Wei, Y.; Miyamoto, S; Asakawa, M.R.; Imasaki, K.

    2012-01-01

    Smith–Purcell radiation occurs when an electron passes close to the surface of a metallic grating. The radiation becomes coherent when the length of the electron bunch is smaller than the wavelength of the radiation. A train of periodic bunches can enhance the spectral intensity by changing the angular and spectral distribution of the radiation. This is called super-radiant Smith–Purcell radiation, and has been observed in experiments and particle-in-cell simulations. In this paper, we introduce a new method to study this effect by calculating the reflected waves of an incident evanescent wave from periodic line charges. The reflection coefficients are numerically computed, and the spectral distributions of the super-radiant radiation are demonstrated. These analytical results are in agreement with those obtained through part-in-cell simulations.

  2. Cautious but Committed: Moving Toward Adaptive Planning and Operation Strategies for Renewable Energy's Wildlife Implications

    Köppel, Johann; Dahmen, Marie; Helfrich, Jennifer; Schuster, Eva; Bulling, Lea

    2014-10-01

    Wildlife planning for renewable energy must cope with the uncertainties of potential wildlife impacts. Unfortunately, the environmental policies which instigate renewable energy and those which protect wildlife are not coherently aligned—creating a green versus green dilemma. Thus, climate mitigation efforts trigger renewable energy development, but then face substantial barriers from biodiversity protection instruments and practices. This article briefly reviews wind energy and wildlife interactions, highlighting the lively debated effects on bats. Today, planning and siting of renewable energy are guided by the precautionary principle in an attempt to carefully address wildlife challenges. However, this planning attitude creates limitations as it struggles to negotiate the aforementioned green versus green dilemma. More adaptive planning and management strategies and practices hold the potential to reconcile these discrepancies to some degree. This adaptive approach is discussed using facets of case studies from policy, planning, siting, and operational stages of wind energy in Germany and the United States, with one case showing adaptive planning in action for solar energy as well. This article attempts to highlight the benefits of more adaptive approaches as well as the possible shortcomings, such as reduced planning security for renewable energy developers. In conclusion, these studies show that adaptive planning and operation strategies can be designed to supplement and enhance the precautionary principle in wildlife planning for green energy.

  3. Cautious but committed: moving toward adaptive planning and operation strategies for renewable energy's wildlife implications.

    Köppel, Johann; Dahmen, Marie; Helfrich, Jennifer; Schuster, Eva; Bulling, Lea

    2014-10-01

    Wildlife planning for renewable energy must cope with the uncertainties of potential wildlife impacts. Unfortunately, the environmental policies which instigate renewable energy and those which protect wildlife are not coherently aligned-creating a green versus green dilemma. Thus, climate mitigation efforts trigger renewable energy development, but then face substantial barriers from biodiversity protection instruments and practices. This article briefly reviews wind energy and wildlife interactions, highlighting the lively debated effects on bats. Today, planning and siting of renewable energy are guided by the precautionary principle in an attempt to carefully address wildlife challenges. However, this planning attitude creates limitations as it struggles to negotiate the aforementioned green versus green dilemma. More adaptive planning and management strategies and practices hold the potential to reconcile these discrepancies to some degree. This adaptive approach is discussed using facets of case studies from policy, planning, siting, and operational stages of wind energy in Germany and the United States, with one case showing adaptive planning in action for solar energy as well. This article attempts to highlight the benefits of more adaptive approaches as well as the possible shortcomings, such as reduced planning security for renewable energy developers. In conclusion, these studies show that adaptive planning and operation strategies can be designed to supplement and enhance the precautionary principle in wildlife planning for green energy.

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

    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.

  5. Free of pollution gas - an utopia or attainable goal? Gas radiant burner with a small capacity

    Hofbauer, P.; Bornscheuer, W.

    1993-01-01

    The firm Viessmann has developed a gas radiant burner for boiler capacities up to 100 kN combusting gas with extremely low pollutant emissions. This is possible since from the reaction zone a considerable part of the combustion heat is delivered through radiation by means of a glowing special steel structure. The theoretical fundamentals are explained by means of considerations regarding the equilibrium and a reaction kinetic numerical model. (orig.) [de

  6. Influence of individual heat pumps on wind power integration – Energy system investments and operation

    Hedegaard, Karsten; Münster, Marie

    2013-01-01

    Individual heat pumps are expected to constitute a significant electricity demand in future energy systems. This demand becomes flexible if investing in complementing heat storage capabilities. In this study, we analyse how the heat pumps can influence the integration of wind power by applying...... an energy system model that optimises both investments and operation, and covers various heat storage options. The Danish energy system by 2030 with around 50–60% wind power is used as a case study. Results show that the heat pumps, even without flexible operation, can contribute significantly...... to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO2 emissions. Investments in heat storages can provide only moderate system benefits in these respects. The main benefit of the flexible heat pump operation is a reduced need for peak/reserve capacity, which is also...

  7. Effects of cryogen spray cooling and high radiant exposures on selective vascular injury during laser irradiation of human skin.

    Tunnell, James W; Chang, David W; Johnston, Carol; Torres, Jorge H; Patrick, Charles W; Miller, Michael J; Thomsen, Sharon L; Anvari, Bahman

    2003-06-01

    Increasing radiant exposure offers a means to increase treatment efficacy during laser-mediated treatment of vascular lesions, such as port-wine stains; however, excessive radiant exposure decreases selective vascular injury due to increased heat generation within the epidermis and collateral damage to perivascular collagen. To determine if cryogen spray cooling could be used to maintain selective vascular injury (ie, prevent epidermal and perivascular collagen damage) when using high radiant exposures (16-30 J/cm2). Observational study. Academic hospital and research laboratory. Twenty women with normal abdominal skin (skin phototypes I-VI). Skin was irradiated with a pulsed dye laser (wavelength = 585 nm; pulse duration = 1.5 milliseconds; 5-mm-diameter spot) using various radiant exposures (8-30 J/cm2) without and with cryogen spray cooling (50- to 300-millisecond cryogen spurts). Hematoxylin-eosin-stained histologic sections from each irradiated site were examined for the degree of epidermal damage, maximum depth of red blood cell coagulation, and percentage of vessels containing perivascular collagen coagulation. Long cryogen spurt durations (>200 milliseconds) protected the epidermis in light-skinned individuals (skin phototypes I-IV) at the highest radiant exposure (30 J/cm2); however, epidermal protection could not be achieved in dark-skinned individuals (skin phototypes V-VI) even at the lowest radiant exposure (8 J/cm2). The red blood cell coagulation depth increased with increasing radiant exposure (to >2.5 mm for skin phototypes I-IV and to approximately 1.2 mm for skin phototypes V-VI). In addition, long cryogen spurt durations (>200 milliseconds) prevented perivascular collagen coagulation in all skin types. Cryogen spurt durations much longer than those currently used in therapy (>200 milliseconds) may be clinically useful for protecting the epidermis and perivascular tissues when using high radiant exposures during cutaneous laser therapies

  8. Inverse optimal design of the radiant heating in materials processing and manufacturing

    Fedorov, A. G.; Lee, K. H.; Viskanta, R.

    1998-12-01

    Combined convective, conductive, and radiative heat transfer is analyzed during heating of a continuously moving load in the industrial radiant oven. A transient, quasi-three-dimensional model of heat transfer between a continuous load of parts moving inside an oven on a conveyor belt at a constant speed and an array of radiant heaters/burners placed inside the furnace enclosure is developed. The model accounts for radiative exchange between the heaters and the load, heat conduction in the load, and convective heat transfer between the moving load and oven environment. The thermal model developed has been used to construct a general framework for an inverse optimal design of an industrial oven as an example. In particular, the procedure based on the Levenberg-Marquardt nonlinear least squares optimization algorithm has been developed to obtain the optimal temperatures of the heaters/burners that need to be specified to achieve a prescribed temperature distribution of the surface of a load. The results of calculations for several sample cases are reported to illustrate the capabilities of the procedure developed for the optimal inverse design of an industrial radiant oven.

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

    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.

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

    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.

  11. Optimal dimensioning of low-energy district heating networks with operational planning

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    in design stage resulted in satisfaction of heat demand of the house in low temperature operation. In this paper the operational planning of the low-energy DH systems was investigated to reduce the dimensions of the distribution network with consideration given both to current high-heat and future low......-heat demand situations. The operational planning was based on boosting (increasing) the supply temperature at peak-demand situations which occur rarely over a year period. Hence optimal pipe dimensions of low-energy DH systems were investigated based on the dynamic response of in-house heating systems...... of operational planning in comparison to DH network dimensioned according to high heat demand situation....

  12. Efficient energy consumption and operation management in a smart building with microgrid

    Zhang, Di; Shah, Nilay; Papageorgiou, Lazaros G.

    2013-01-01

    Highlights: • An MILP model is formulated for energy consumption scheduling in a smart building. • Domestic appliances from multiple smart homes are considered. • Equipment operation and power consumption tasks starting time are scheduled. • Results from two examples indicate cost savings and power peak reduction. • Peak demand charge scheme is adopted to reduce the peak demand from grid. - Abstract: Microgrid works as a local energy provider for domestic buildings to reduce energy expenses and gas emissions by utilising distributed energy resources (DERs). The rapid advances in computing and communication capabilities enable the concept smart buildings become possible. Most energy-consuming household tasks do not need to be performed at specific times but rather within a preferred time. If these types of tasks can be coordinated among multiple homes so that they do not all occur at the same time yet still satisfy customers’ requirement, the energy cost and power peak demand could be reduced. In this paper, the optimal scheduling of smart homes’ energy consumption is studied using a mixed integer linear programming (MILP) approach. In order to minimise a 1-day forecasted energy consumption cost, DER operation and electricity-consumption household tasks are scheduled based on real-time electricity pricing, electricity task time window and forecasted renewable energy output. Peak demand charge scheme is also adopted to reduce the peak demand from grid. Two numerical examples on smart buildings of 30 homes and 90 homes with their own microgrid indicate the possibility of cost savings and electricity consumption scheduling peak reduction through the energy consumption and better management of DER operation

  13. CERN-group conceptual design of a fast neutron operated high power energy amplifier

    Rubbia, C.; Rubio, J.A.; Buono, S.

    1997-01-01

    The practical feasibility of an Energy Amplifier (EA) with power and power density which are comparable to the ones of the present generation of large PWR is discussed in this paper. This is only possible with fast neutrons. Schemes are described which offer a high gain, a large maximum power density and an extended burn-up, well in excess of 100 GW x d/t corresponding to about five years at full power operation with no intervention on the fuel core. The following topics are discussed: physics considerations and parameter definition, the accelerator complex, the energy amplifier unit, computer simulated operation, and fuel cycle closing

  14. The Emissions Impacts of Varied Energy Storage Operational Objectives Across Regions

    Barrett, Emily L.; Thayer, Brandon L.; Studarus, Karen E.; Pal, Seemita

    2017-11-15

    The emissions consequences of smart grid technologies can be significant but are not always intuitive. This is particularly true in the implementation of energy storage (ES) systems that are being increasingly adopted to integrate more intermittent renewable generation, to reduce peak demand, and to participate in energy markets. Both the location of the ES system within the grid and the way it is operated will dictate its resulting impacts. The Grid Project Impact Quantification tool can provide insight into some of the emissions implications of hypothetical ES systems for a variety of operational objectives in diverse locations within the United States.

  15. CERN-group conceptual design of a fast neutron operated high power energy amplifier

    Rubbia, C; Rubio, J A [European Organization for Nuclear Research, CERN, Geneva (Switzerland); Buono, S [Laboratoire du Cyclotron, Nice (France); and others

    1997-11-01

    The practical feasibility of an Energy Amplifier (EA) with power and power density which are comparable to the ones of the present generation of large PWR is discussed in this paper. This is only possible with fast neutrons. Schemes are described which offer a high gain, a large maximum power density and an extended burn-up, well in excess of 100 GW x d/t corresponding to about five years at full power operation with no intervention on the fuel core. The following topics are discussed: physics considerations and parameter definition, the accelerator complex, the energy amplifier unit, computer simulated operation, and fuel cycle closing. 84 refs, figs, tabs.

  16. Operation of Dokan Reservoir under Stochastic Conditions as Regards the Inflows and the Energy Demands

    Rashed, G. I.

    2018-02-01

    This paper presented a way of obtaining certain operating rules on time steps for the management of a large reservoir operation with a peak hydropower plant associated to it. The rules were allowed to have the form of non-linear regression equations which link a decision variable (here the water volume in the reservoir at the end of the time step) by several parameters influencing it. This paper considered the Dokan hydroelectric development KR-Iraq, which operation data are available for. It was showing that both the monthly average inflows and the monthly power demands are random variables. A model of deterministic dynamic programming intending the minimization of the total amount of the squares differences between the demanded energy and the generated energy is run with a multitude of annual scenarios of inflows and monthly required energies. The operating rules achieved allow the efficient and safe management of the operation and it is quietly and accurately known the forecast of the inflow and of the energy demand on the next time step.

  17. Dokan Hydropower Reservoir Operation under Stochastic Conditions as Regards the Inflows and the Energy Demands

    Izat Rashed, Ghamgeen

    2018-03-01

    This paper presented a way of obtaining certain operating rules on time steps for the management of a large reservoir operation with a peak hydropower plant associated to it. The rules were allowed to have the form of non-linear regression equations which link a decision variable (here the water volume in the reservoir at the end of the time step) by several parameters influencing it. This paper considered the Dokan hydroelectric development KR-Iraq, which operation data are available for. It was showing that both the monthly average inflows and the monthly power demands are random variables. A model of deterministic dynamic programming intending the minimization of the total amount of the squares differences between the demanded energy and the generated energy is run with a multitude of annual scenarios of inflows and monthly required energies. The operating rules achieved allow the efficient and safe management of the operation and it is quietly and accurately known the forecast of the inflow and of the energy demand on the next time step.

  18. A hydraulic test stand for demonstrating the operation of Eaton’s energy recovery system (ERS)

    Wang, Meng (Rachel); Danzl, Per; Mahulkar, Vishal; Piyabongkarn, Damrongrit (Neng); Brenner, Paul

    2016-01-01

    Fuel cost represents a significant operating expense for owners and fleet managers of hydraulic off-highway vehicles. Further, the upcoming Tier IV compliance for off-highway applications will create further expense for after-treatment and cooling. Solutions that help address these factors motivate fleet operators to consider and pursue more fuelefficient hydraulic energy recovery systems. Electrical hybridization schemes are typically complex, expensive, and often do not satisfy customer pay...

  19. Using Large-Scale Cooperative Control to Manage Operational Uncertainties for Aquifer Thermal Energy Storage

    Jaxa-Rozen, M.; Rostampour, V.; Kwakkel, J. H.; Bloemendal, M.

    2017-12-01

    Seasonal Aquifer Thermal Energy Storage (ATES) technology can help reduce the demand of energy for heating and cooling in buildings, and has become a popular option for larger buildings in northern Europe. However, the larger-scale deployment of this technology has evidenced some issues of concern for policymakers; in particular, recent research shows that operational uncertainties contribute to inefficient outcomes under current planning methods for ATES. For instance, systems in the Netherlands typically use less than half of their permitted pumping volume on an annual basis. This overcapacity gives users more flexibility to operate their systems in response to the uncertainties which drive building energy demand; these include short-term operational factors such as weather and occupancy, and longer-term, deeply uncertain factors such as changes in climate and aquifer conditions over the lifespan of the buildings. However, as allocated subsurface volume remains unused, this situation limits the adoption of the technology in dense areas. Previous work using coupled agent-based/geohydrological simulation has shown that the cooperative operation of neighbouring ATES systems can support more efficient spatial planning, by dynamically managing thermal interactions in response to uncertain operating conditions. An idealized case study with centralized ATES control thus showed significant improvements in the energy savings which could obtained per unit of allocated subsurface volume, without degrading the recovery performance of systems. This work will extend this cooperative approach for a realistic case study of ATES planning in the city of Utrecht, in the Netherlands. This case was previously simulated under different scenarios for individual ATES operation. The poster will compare these results with a cooperative case under which neighbouring systems can coordinate their operation to manage interactions. Furthermore, a cooperative game-theoretical framework will be

  20. Reduction in energy consumption and operating cost in a dried corn warehouse using logistics techniques

    Korrakot Y. Tippayawong

    2013-06-01

    Full Text Available Corn is one of the major economic crops in Thailand. Corn postharvest operation involves various practices that consume a large amount of energy. Different energy conservation measures have been implemented but logistics consideration is not normally employed. In this work, attempt has been made to demonstrate that logistics techniques can offer a significant reduction in energy and cost. The main objective of this work is to identify and demonstrate possible approaches to improving energy efficiency and reducing operating cost for a dried corn warehouse operator. Three main problems are identified: (i relatively high fuel consumption for internal transfer process, (ii low quality of dried corn, and (iii excess expenditure on outbound transportation. Solutions are proposed and implemented using logistics operations. Improvement is achieved using plant layout and shortest path techniques, resulting in a reduction of almost 50% in energy consumption for the internal transfer process. Installation of an air distributor in the grain storage unit results in a decrease in loss due to poor-quality dried corn from 17% to 10%. Excess expenditure on dried corn distribution is reduced by 6% with application of a global positioning system.

  1. An RF energy harvesting power management circuit for appropriate duty-cycled operation

    Shirane, Atsushi; Ito, Hiroyuki; Ishihara, Noboru; Masu, Kazuya

    2015-04-01

    In this study, we present an RF energy harvesting power management unit (PMU) for battery-less wireless sensor devices (WSDs). The proposed PMU realizes a duty-cycled operation that is divided into the energy charging time and discharging time. The proposed PMU detects two types of timing, thus, the appropriate timing for the activation can be recognized. The activation of WSDs at the proper timing leads to energy efficient operation and stable wireless communication. The proposed PMU includes a hysteresis comparator (H-CMP) and an RF signal detector (RF-SD) to detect the timings. The proposed RF-SD can operate without the degradation of charge efficiency by reusing the RF energy harvester (RF-EH) and H-CMP. The PMU fabricated in a 180 nm Si CMOS demonstrated the charge operation using the RF signal at 915 MHz and the two types of timing detection with less than 124 nW in the charge phase. Furthermore, in the active phase, the PMU generates a 0.5 V regulated power supply from the charged energy.

  2. Energy and water quality management systems for water utility's operations: a review.

    Cherchi, Carla; Badruzzaman, Mohammad; Oppenheimer, Joan; Bros, Christopher M; Jacangelo, Joseph G

    2015-04-15

    Holistic management of water and energy resources is critical for water utilities facing increasing energy prices, water supply shortage and stringent regulatory requirements. In the early 1990s, the concept of an integrated Energy and Water Quality Management System (EWQMS) was developed as an operational optimization framework for solving water quality, water supply and energy management problems simultaneously. Approximately twenty water utilities have implemented an EWQMS by interfacing commercial or in-house software optimization programs with existing control systems. For utilities with an installed EWQMS, operating cost savings of 8-15% have been reported due to higher use of cheaper tariff periods and better operating efficiencies, resulting in the reduction in energy consumption of ∼6-9%. This review provides the current state-of-knowledge on EWQMS typical structural features and operational strategies and benefits and drawbacks are analyzed. The review also highlights the challenges encountered during installation and implementation of EWQMS and identifies the knowledge gaps that should motivate new research efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Advanced energy design and operation technologies research: Recommendations for a US Department of Energy multiyear program plan

    Brambley, M.R.; Crawley, D.B.; Hostetler, D.D.; Stratton, R.C.; Addision, M.S.; Deringer, J.J.; Hall, J.D.; Selkowitz, S.E.

    1988-12-01

    This document describes recommendations for a multiyear plan developed for the US Department of Energy (DOE) as part of the Advanced Energy Design and Operation Technologies (AEDOT) project. The plan is an outgrowth of earlier planning activities conducted for DOE as part of design process research under the Building System Integration Program (BSIP). The proposed research will produce intelligent computer-based design and operation technologies for commercial buildings. In this document, the concept is explained, the need for these new computer-based environments is discussed, the benefits are described, and a plan for developing the AEDOT technologies is presented for the 9-year period beginning FY 1989. 45 refs., 37 figs., 9 tabs.

  4. Optimum pulse duration and radiant exposure for vascular laser therapy of dark port-wine skin: a theoretical study

    Tunnell, James W.; Anvari, Bahman; Wang, Lihong V.

    2003-01-01

    Laser therapy for cutaneous hypervascular malformations such as port-wine stain birthmarks is currently not feasible for dark-skinned individuals. We study the effects of pulse duration, radiant exposure, and cryogen spray cooling (CSC) on the thermal response of skin, using a Monte Carlo based optical-thermal model. Thermal injury to the epidermis decreases with increasing pulse duration during irradiation at a constant radiant exposure; however, maintaining vascular injury requires that the radiant exposure also increase. At short pulse durations, only a minimal increase in radiant exposure is necessary for a therapeutic effect to be achieved because thermal diffusion from the vessels is minimal. However, at longer pulse durations the radiant exposure must be greatly increased. There exists an optimum pulse duration at which minimal damage to the epidermis and significant injury within the targeted vasculature occur. For example, the model predicts optimum pulse durations of approximately 1.5, 6, and 20 ms for vessel diameters of 40, 80, and 120 μm, respectively. Optimization of laser pulse duration and radiant exposure in combination with CSC may offer a means to treat cutaneous lesions in dark-skinned individuals

  5. Designing an Energy Storage System Fuzzy PID Controller for Microgrid Islanded Operation

    Jong-Yul Kim; Hak-Man Kim; Seul-Ki Kim; Jin-Hong Jeon; Heung-Kwan Choi

    2011-01-01

    Recently, interest in microgrids, which are composed of distributed generation (DG), distributed storage (DS), and loads, has been growing as a potentially effective clean energy system to mitigate against climate change. The microgrid is operated in the grid-connected mode and the islanded mode according to the conditions of the upstream power grid. The role of the energy storage system (ESS) is especially important to maintain constant the frequency and voltage of an islanded microgrid. For...

  6. Multi-objective design and operation of Solid Oxide Fuel Cell (SOFC) Triple Combined-cycle Power Generation systems: Integrating energy efficiency and operational safety

    Sharifzadeh, Mahdi; Meghdari, Mojtaba; Rashtchian, Davood

    2017-01-01

    Highlights: • Integrating Solid Oxide Fuel Cells with thermal power plants enhance overall energy efficiency. • However, the high degree of process integration in hybrid power plants limits the operating window. • Multi-objective optimization was applied for integrated design and operation. • The Pareto optimal solutions demonstrated strong trade-off between energy efficiency and operational safety. - Abstract: Energy efficiency is one of the main pathways for energy security and environmental protection. In fact, the International Energy Agency asserts that without energy efficiency, 70% of targeted emission reductions are not achievable. Despite this clarity, enhancing the energy efficiency introduce significant challenge toward process operation. The reason is that the methods applied for energy-saving pose the process operation at the intersection of safety constraints. The present research aims at uncovering the trade-off between safe operation and energy efficiency; an optimization framework is developed that ensures process safety and simultaneously optimizes energy-efficiency, quantified in economic terms. The developed optimization framework is demonstrated for a solid oxide fuel cell (SOFC) power generation system. The significance of this industrial application is that SOFC power plants apply a highly degree of process integration resulting in very narrow operating windows. However, they are subject to significant uncertainties in power demand. The results demonstrate a strong trade-off between the competing objectives. It was observed that highly energy-efficient designs feature a very narrow operating window and limited flexibility. For instance, expanding the safe operating window by 100% will incur almost 47% more annualized costs. Establishing such a trade-off is essential for realizing energy-saving.

  7. STUDY ON ENERGY EXCHANGE PROCESSES IN NORMAL OPERATION OF METRO ROLLING STOCK WITH REGENERATIVE BRAKING SYSTEMS

    A. O. Sulym

    2017-10-01

    Full Text Available Purpose. The analysis of the existing studies showed that the increasing of energy efficiency of metro rolling stock becomes especially important and requires timely solutions. It is known that the implementation of regenerative braking systems on rolling stock will allow significantly solving this problem. It was proved that one of the key issues regarding the introduction of the above-mentioned systems is research on efficient use of electric energy of regenerative braking. The purpose of the work is to evaluate the amount of excessive electric power of regenerative braking under normal operation conditions of the rolling stock with regenerative braking systems for the analysis of the energy saving reserves. Methodology. Quantifiable values of electrical energy consumed for traction, returned to the contact line and dissipated in braking resistors (excessive energy are determined using results of experimental studies of energy exchange processes under normal operating conditions of metro rolling stock with regenerative systems. Statistical methods of data processing were applied as well. Findings. Results of the studies analysis of metro rolling stock operation under specified conditions in Sviatoshinsko-Brovarskaia line of KP «Kyiv Metro system» stipulate the following: 1 introduction of regenerative braking systems into the rolling stock allows to return about 17.9-23.2% of electrical energy consumed for traction to the contact line; 2 there are reserves for improving of energy efficiency of rolling stock with regenerative systems at the level of 20.2–29.9 % of electrical energy consumed for traction. Originality. For the first time, it is proved that the most significant factor that influences the quantifiable values of the electrical energy regeneration is a track profile. It is suggested to use coefficients which indicate the amount and reserves of unused (excessive electrical energy for quantitative evaluation. Studies on

  8. Optimization of cascade hydropower system operation by genetic algorithm to maximize clean energy output

    Aida Tayebiyan

    2016-06-01

    Full Text Available Background: Several reservoir systems have been constructed for hydropower generation around the world. Hydropower offers an economical source of electricity with reduce carbon emissions. Therefore, it is such a clean and renewable source of energy. Reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue. Yet, reservoir systems are inefficiently operated and manage according to policies determined at the construction time. It is worth noting that with little enhancement in operation of reservoir system, there could be an increase in efficiency of the scheme for many consumers. Methods: This research develops simulation-optimization models that reflect discrete hedging policy (DHP to manage and operate hydropower reservoir system and analyse it in both single and multireservoir system. Accordingly, three operational models (2 single reservoir systems and 1 multi-reservoir system were constructed and optimized by genetic algorithm (GA. Maximizing the total power generation in horizontal time is chosen as an objective function in order to improve the functional efficiency in hydropower production with consideration to operational and physical limitations. The constructed models, which is a cascade hydropower reservoirs system have been tested and evaluated in the Cameron Highland and Batang Padang in Malaysia. Results: According to the given results, usage of DHP for hydropower reservoir system operation could increase the power generation output to nearly 13% in the studied reservoir system compared to present operating policy (TNB operation. This substantial increase in power production will enhance economic development. Moreover, the given results of single and multi-reservoir systems affirmed that hedging policy could manage the single system much better than operation of the multi-reservoir system. Conclusion: It can be summarized that DHP is an efficient and feasible policy, which could be used

  9. Contributing to a green energy economy? A macroeconomic analysis of an energy efficiency program operated by a Swiss utility

    Yushchenko, Alisa; Patel, Martin Kumar

    2016-01-01

    Highlights: • Our input–output model allows estimating impacts of energy efficiency programs on GDP and employment in Switzerland. • We provide with a deeper insight into modeling of income impacts of energy savings with regard to input–output method. • Geneva case study demonstrates that energy efficiency programs can have positive macroeconomic impacts in Switzerland. • Our results help to understand how to enhance positive macroeconomic impacts of energy efficiency programs. • We provide policy recommendations for further development of energy efficiency programs. - Abstract: In order to enhance energy efficiency as a pillar of transition to a green energy economy it is important to understand whether and under which conditions energy efficiency programs could have positive economic and social impacts. There are a growing number of studies on macroeconomic impacts of energy efficiency programs for various countries and regions. However, in Switzerland only few evaluations have been performed. The present study evaluates the impacts on GDP and employment of Geneva’s energy efficiency program portfolio éco21 which is operated by the local utility. Two programs aiming for electricity savings in the residential sector are analyzed: Eco-sociales targets social housing and Communs d’immeubles focuses on common spaces in buildings. An input–output model is developed, based on the Swiss input–output table, program administrator data, Swiss, and European statistics. Both impacts of initial expenditure and energy cost savings are evaluated. We estimate and compare the impacts of the two programs and discuss factors that cause differences. Our results show that energy efficiency programs can have positive impacts on GDP and employment. According to our estimates, each Swiss Franc (CHF) spent within the energy efficiency program creates approximately 0.2 CHF of additional GDP compared to the reference case scenario. Net impacts on employment are

  10. Vibration energy harvesting based monitoring of an operational bridge undergoing forced vibration and train passage

    Cahill, Paul; Hazra, Budhaditya; Karoumi, Raid; Mathewson, Alan; Pakrashi, Vikram

    2018-06-01

    The application of energy harvesting technology for monitoring civil infrastructure is a bourgeoning topic of interest. The ability of kinetic energy harvesters to scavenge ambient vibration energy can be useful for large civil infrastructure under operational conditions, particularly for bridge structures. The experimental integration of such harvesters with full scale structures and the subsequent use of the harvested energy directly for the purposes of structural health monitoring shows promise. This paper presents the first experimental deployment of piezoelectric vibration energy harvesting devices for monitoring a full-scale bridge undergoing forced dynamic vibrations under operational conditions using energy harvesting signatures against time. The calibration of the harvesters is presented, along with details of the host bridge structure and the dynamic assessment procedures. The measured responses of the harvesters from the tests are presented and the use the harvesters for the purposes of structural health monitoring (SHM) is investigated using empirical mode decomposition analysis, following a bespoke data cleaning approach. Finally, the use of sequential Karhunen Loeve transforms to detect train passages during the dynamic assessment is presented. This study is expected to further develop interest in energy-harvesting based monitoring of large infrastructure for both research and commercial purposes.

  11. Operating Wireless Sensor Nodes without Energy Storage: Experimental Results with Transient Computing

    Faisal Ahmed

    2016-12-01

    Full Text Available Energy harvesting is increasingly used for powering wireless sensor network nodes. Recently, it has been suggested to combine it with the concept of transient computing whereby the wireless sensor nodes operate without energy storage capabilities. This new combined approach brings benefits, for instance ultra-low power nodes and reduced maintenance, but also raises new challenges, foremost dealing with nodes that may be left without power for various time periods. Although transient computing has been demonstrated on microcontrollers, reports on experiments with wireless sensor nodes are still scarce in the literature. In this paper, we describe our experiments with solar, thermal, and RF energy harvesting sources that are used to power sensor nodes (including wireless ones without energy storage, but with transient computing capabilities. The results show that the selected solar and thermal energy sources can operate both the wired and wireless nodes without energy storage, whereas in our specific implementation, the developed RF energy source can only be used for the selected nodes without wireless connectivity.

  12. Sensitivity analysis for daily building operation from the energy and thermal comfort standpoint

    Ignjatović Marko G.

    2016-01-01

    Full Text Available Improving energy performance of buildings is one of the most important tasks for reaching sustainability. Assessing building energy consumption is performed more often with specialized simulation tools. Sensitivity analysis proved to be a valuable tool for creating more reliable and realistic building energy models and better buildings. This paper briefly describes the methodology for running global sensitivity analysis and tools that can be used, and presents the results of such an analysis conducted for winter period, daily, on input variables covering a real building's operation, control and occupant related parameters that affect both thermal comfort and heating energy consumption. Two sets of inputs were created. The only difference between these sets is an addition of clothing insulation and occupant heat gain as input variables. The reference building was simulated for three distinctive winter weeks. Two additional input variables have an effect especially on thermal comfort, but they do not disturb the relative order of other influential input variables. The common influential variables for both energy consumption and thermal comfort were identified and are: air handling unit sup-ply temperature and airflow rate and control system related parameters. This can help in future research into implementing the simulation-assisted optimized operation in real buildings. [Projekat Ministarstva nauke Republike Srbije, br. TR-33051: The concept of sustainable energy supply of settlements with energy efficient buildings

  13. Co-operative research for future energy supply; Gemeinsam Forschen fuer die Energie der Zukunft

    Stadermann, G.; Szczepanski, P. (comps.)

    2000-10-01

    The FVS ForschungsVerbund Sonnenenergie was founded in 1990 and covers the whole spectrum of solar and renewable energy sources, from solid state physics to agriculture and technology assessment. [German] Seit der Entstehnung des FVS ForschungsVerbund Sonnenenergie haben sich die Rahmenbedingungen fuer die Erforschung der solaren und erneuerbaren Energien verbessert: Sie wurden in den letzten Jahren weiter erschlossen und haben an Bekanntheit und Sympathie gewonnen. Die von der Bundesregierung angestrebte Energiewende bedeutet eine Zaesur in der deutschen Energieversorgung und fuehrt zu einer staerkeren Foerderung erneuerbarer Energien. Sie werden zunehmend als markt- und zukunftsfaehiger Wirtschaftsfaktor wahrgenommen, zu dessen Erschliessung intensive Forschung und Entwicklung notwendig ist. Der Verbund gewinnt daher verstaerkt die Industrie und die Energiewirtschaft als Kooperationspartner im Forschungssektor. Das Themenspektrum im FVS ForschungsVerbund Sonnenenergie umfasst weitgehend alle solaren und erneuerbaren Energien. Diese Themen beinhalten eine Fuelle von einzelnen wissenschaftlichen Problemstellungen von der Festkoerperphysik bis zu agrarwissenschaftlichen Fragen nachwachsender Energierohstoffe und zur Technologiebewertung. (orig.)

  14. Technical Diagnostics of Ventilation Units for Energy Efficiency and Safety of Operation

    Kuzin Evgeny

    2017-01-01

    Full Text Available The article considers the questions of application of technical diagnostics fan installations methods for providing safe operation, the system of the technical maintenance improvement and repair. Due to the feet that one of the most important aspects in fan operation in mining is energy efficiency and energy saving, the lack of the data in the control of the level in vibration of stationary sensors is shown. The necessity of taking into account the geometric parameters of the intake channel has been shown, and also the necessity of creation of the reference masks for the assessment of technical condition and energy efficiency when operating fan installations in mining. The results of technical diagnostics of the main fans using the methods of vibration diagnostics are provided. Aspects of vibration at characteristic points are shown. The necessity for further accumulation of data characterizing vibration for adjustment of the reference masks and more accurate detection of defects and deviations from the energy-efficient mode of operation of the fan installations is given.

  15. Cooperative Operation of Battery Energy Storage System and Dispatchable Distributed Generations in Microgrid System

    Zhao, Haoran; Cha, Seung-Tae; Rasmussen, Claus Nygaard

    Microgrid is an efficient solution to the utilization of renewable energy. According to the different operations (grid-connected or islanded), a fuzzy-logic based control strategy between BESS and dispatchable DG units is proposed in this paper, where the BESS plays a key role. The effectiveness ...

  16. Task Force on Energy Systems for Forward/Remote Operating Bases

    2016-08-01

    nuclear power energy systems ......................................................... 30 7.2.1 Radioisotope thermoelectric generators...issue, the Task Force found efforts to provide the most efficient methods for power production at the prime-contract level have been hampered by...management. Engineer Prime Power Operations21 describes theater level power infrastructure and inter-service responsibilities and, although dated from

  17. A genetic algorithm solution for the operation of green LTE networks with energy and environment considerations

    Ghazzai, Hakim; Yaacoub, Elias E.; Alouini, Mohamed-Slim; Abu-Dayya, Adnan A.

    2012-01-01

    , as additional power sources in smart grids, becomes a real challenge to network operators to reduce power costs. In this paper, we propose a method based on genetic algorithms that decreases the energy consumption of a Long-Term Evolution (LTE) cellular network

  18. Actinide data in the thermal energy range - International Evaluation Co-operation Volume 3

    Tellier, Henri; Weigmann, H.; Sowerby, M.; Mattes, Margarete; Matsunobu, Hiroyuki; Tsuchihashi, Keichiro; Halsall, M.J.; Weston, L.; Deruytter, A.J.

    1994-01-01

    A Working Party on International Evaluation Co-operation was established under the sponsorship of the OECD/NEA Nuclear Science Committee (NSC) to promote the exchange of information on nuclear data evaluations, validation, and related topics. Its aim is also to provide a framework for co-operative activities between members of the major nuclear data evaluation projects. This includes the possible exchange of scientists in order to encourage co-operation. Requirements for experimental data resulting from this activity are compiled. The Working Party determines common criteria for evaluated nuclear data files with a view to assessing and improving the quality and completeness of evaluated data. The Parties to the project are: ENDF (United States), JEFF/EFF (NEA Data Bank Member countries), and JENDL (Japan). Co-operation with evaluation projects of non-OECD countries are organised through the Nuclear Data Section of the International Atomic Energy Agency (IAEA). This report was issued by a Subgroup investigating actinide data in the thermal energy range. Thermal nuclear constants for the primary actinides have been extensively studies, but the most recent evaluations are not in full agreement with thermal reactor calculations. The objective of the Subgroup was to identify the origin of these differences and to reassess the recent evaluations. A considerable effort was devoted to the η of U-235, where analysis of lattice temperature coefficient measurements has suggested an energy dependent shape below thermal energy

  19. Accelerating the commercialization on new technologies. [free market operation of federal alternate energy sources programs

    Kuehn, T. J.; Nawrocki, P. M.

    1978-01-01

    It is suggested that federal programs for hastening the adoption of alternative energy sources must operate within the free market structure. Five phases of the free market commercialization process are described. Federal role possibilities include information dissemination and funding to stimulate private sector activities within these five phases, and federally sponsored procedures for accelerating commercialization of solar thermal small power systems are considered.

  20. Technical Diagnostics of Ventilation Units for Energy Efficiency and Safety of Operation

    Kuzin, Evgeny; Shahmanov, Vitality; Dubinkin, Dmitriy

    2017-11-01

    The article considers the questions of application of technical diagnostics fan installations methods for providing safe operation, the system of the technical maintenance improvement and repair. Due to the feet that one of the most important aspects in fan operation in mining is energy efficiency and energy saving, the lack of the data in the control of the level in vibration of stationary sensors is shown. The necessity of taking into account the geometric parameters of the intake channel has been shown, and also the necessity of creation of the reference masks for the assessment of technical condition and energy efficiency when operating fan installations in mining. The results of technical diagnostics of the main fans using the methods of vibration diagnostics are provided. Aspects of vibration at characteristic points are shown. The necessity for further accumulation of data characterizing vibration for adjustment of the reference masks and more accurate detection of defects and deviations from the energy-efficient mode of operation of the fan installations is given.

  1. Matrix elements of the potential energy operator for the six nucleon system between the generating invariants

    Filippov, G.F.; Lopez Trujillo, A.; Rybkin, I.Yu.

    1993-01-01

    The matrix elements of the potential energy operator (which includes central, spin-orbit and tensor components) are calculated between the generating invariants of the cluster basis describing α + d and t+h configurations of the six-nucleon system. (author). 12 refs

  2. Optimization of operation of energy supply systems with co-generation and absorption refrigeration

    Stojiljković Mirko M.

    2012-01-01

    Full Text Available Co-generation systems, together with absorption refrigeration and thermal storage, can result in substantial benefits from the economic, energy and environmental point of view. Optimization of operation of such systems is important as a component of the entire optimization process in pre-construction phases, but also for short-term energy production planning and system control. This paper proposes an approach for operational optimization of energy supply systems with small or medium scale co-generation, additional boilers and heat pumps, absorption and compression refrigeration, thermal energy storage and interconnection to the electric utility grid. In this case, the objective is to minimize annual costs related to the plant operation. The optimization problem is defined as mixed integer nonlinear and solved combining modern stochastic techniques: genetic algorithms and simulated annealing with linear programming using the object oriented “ESO-MS” software solution for simulation and optimization of energy supply systems, developed as a part of this research. This approach is applied to optimize a hypothetical plant that might be used to supply a real residential settlement in Niš, Serbia. Results are compared to the ones obtained after transforming the problem to mixed 0-1 linear and applying the branch and bound method.

  3. Quantum theory with an energy operator defined as a quartic form of the momentum

    Bezák, Viktor, E-mail: bezak@fmph.uniba.sk

    2016-09-15

    Quantum theory of the non-harmonic oscillator defined by the energy operator proposed by Yurke and Buks (2006) is presented. Although these authors considered a specific problem related to a model of transmission lines in a Kerr medium, our ambition is not to discuss the physical substantiation of their model. Instead, we consider the problem from an abstract, logically deductive, viewpoint. Using the Yurke–Buks energy operator, we focus attention on the imaginary-time propagator. We derive it as a functional of the Mehler kernel and, alternatively, as an exact series involving Hermite polynomials. For a statistical ensemble of identical oscillators defined by the Yurke–Buks energy operator, we calculate the partition function, average energy, free energy and entropy. Using the diagonal element of the canonical density matrix of this ensemble in the coordinate representation, we define a probability density, which appears to be a deformed Gaussian distribution. A peculiarity of this probability density is that it may reveal, when plotted as a function of the position variable, a shape with two peaks located symmetrically with respect to the central point.

  4. Investigation the Effects of Operation Methods on Energy Consumption in Agricultural Water Pumping Stations

    M. DelfanAzari

    2017-01-01

    Full Text Available Introduction: The energy crisis has led the world toward the reduction of energy consumption. More than 70 percent of the energy in agriculture sector is used by pumps. In our country, there is no clear standard and guideline and also no adequate supervision for the design, selection, installation and operation of pumping systems appropriate to the circumstances and needs. Consequently, these systems operate with low efficiency and high losses of energy. While more than 20 percent of the world's electricity is consumed by pumps, average pumping efficiency is less than 40%. So evaluation of pumping stations and providing some solutions to increase efficiency and pumping system’s life time and to reduce energy consumption can be an effective in optimization of energy consumption in the country. The main reasons for the low efficiency of pumping systems comparing to potential efficiency are using unsuitable techniques for flow control, hydraulic and physical changes of pumping system during the time, using pumps or motors with low efficiency and poor maintenance. Normally the amount of flow is not constant over the time in a pumping system and needed flow rate is changed at different times. Designing of pumping system should be responsible for peak requirements as well as it must suggest the suitable flow control method to achieve least energy losses for minimum flow requirements. Also one of the main capabilities to reduce energy consumption in pumping stations is improving the flow control method. Using the flow control valves and bypass line with high energy losses is very common. While the use of variable speed pumps (VSPs that supply water requirement with sufficient pressure and minimum amount of energy, is limited due to lack of awareness of designers and (or high initial costs. Materials and Methods: In this study, the operation of the pumping stations under four scenarios (for discharge control in a drip irrigation system was analyzed

  5. Measurement of Underwater Operational Noise Emitted by Wave and Tidal Stream Energy Devices.

    Lepper, Paul A; Robinson, Stephen P

    2016-01-01

    The increasing international growth in the development of marine and freshwater wave and tidal energy harvesting systems has been followed by a growing requirement to understand any associated underwater impact. Radiated noise generated during operation is dependent on the device's physical properties, the sound-propagation environment, and the device's operational state. Physical properties may include size, distribution in the water column, and mechanics/hydrodynamics. The sound-propagation environment may be influenced by water depth, bathymetry, sediment type, and water column acoustic properties, and operational state may be influenced by tidal cycle and wave height among others This paper discusses some of the challenges for measurement of noise characteristics from these devices as well as a case study of the measurement of radiated noise from a full-scale wave energy converter.

  6. Simulation model for wind energy storage systems. Volume II. Operation manual. [SIMWEST code

    Warren, A.W.; Edsinger, R.W.; Burroughs, J.D.

    1977-08-01

    The effort developed a comprehensive computer program for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel and pneumatic). An acronym for the program is SIMWEST (Simulation Model for Wind Energy Storage). The level of detail of SIMWEST is consistent with a role of evaluating the economic feasibility as well as the general performance of wind energy systems. The software package consists of two basic programs and a library of system, environmental, and load components. Volume II, the SIMWEST operation manual, describes the usage of the SIMWEST program, the design of the library components, and a number of simple example simulations intended to familiarize the user with the program's operation. Volume II also contains a listing of each SIMWEST library subroutine.

  7. A New Hybrid Bathroom System Based on Energy Saving Concept

    Cui Bo-wen

    2016-01-01

    Full Text Available Based on the characteristics of hot water supply in bathroom, this article proposes a new hybrid energy hot water supply system. The programmable logic controller(PLC as the master controller was adopted in this system, which could automatically detect and storage main thermal physical of the system, such as temperature, water level, solar radiation intensity, power consumption and so on. The active thermal utilization technology of solar energy, air-source heat pump technology, solar energy intensive natural ventilation technology and low temperature hot water floor radiant heating technology were organically integrated in this system, which has the advantages of energy conservation and environment protection, high automation, safe and reliable operation, etc. At the same time, it can make good use of electric power cost between on-peak and off-peak, and promote the optimal allocation of power resources and reduce the cost, which can achieve the goal of intelligent control and energy saving.

  8. Performance of Optimization Heuristics for the Operational Planning of Multi-energy Storage Systems

    Haas, J.; Schradi, J.; Nowak, W.

    2016-12-01

    In the transition to low-carbon energy sources, energy storage systems (ESS) will play an increasingly important role. Particularly in the context of solar power challenges (variability, uncertainty), ESS can provide valuable services: energy shifting, ramping, robustness against forecast errors, frequency support, etc. However, these qualities are rarely modelled in the operational planning of power systems because of the involved computational burden, especially when multiple ESS technologies are involved. This work assesses two optimization heuristics for speeding up the optimal operation problem. It compares their accuracy (in terms of costs) and speed against a reference solution. The first heuristic (H1) is based on a merit order. Here, the ESS are sorted from lower to higher operational costs (including cycling costs). For each time step, the cheapest available ESS is used first, followed by the second one and so on, until matching the net load (demand minus available renewable generation). The second heuristic (H2) uses the Fourier transform to detect the main frequencies that compose the net load. A specific ESS is assigned to each frequency range, aiming to smoothen the net load. Finally, the reference solution is obtained with a mixed integer linear program (MILP). H1, H2 and MILP are subject to technical constraints (energy/power balance, ramping rates, on/off states...). Costs due to operation, replacement (cycling) and unserved energy are considered. Four typical days of a system with a high share of solar energy were used in several test cases, varying the resolution from one second to fifteen minutes. H1 and H2 achieve accuracies of about 90% and 95% in average, and speed-up times of two to three and one to two orders of magnitude, respectively. The use of the heuristics looks promising in the context of planning the expansion of power systems, especially when their loss of accuracy is outweighed by solar or wind forecast errors.

  9. Modelling and Simulation of the Radiant Field in an Annular Heterogeneous Photoreactor Using a Four-Flux Model

    O. Alvarado-Rolon

    2018-01-01

    Full Text Available This work focuses on modeling and simulating the absorption and scattering of radiation in a photocatalytic annular reactor. To achieve so, a model based on four fluxes (FFM of radiation in cylindrical coordinates to describe the radiant field is assessed. This model allows calculating the local volumetric rate energy absorption (LVREA profiles when the reaction space of the reactors is not a thin film. The obtained results were compared to radiation experimental data from other authors and with the results obtained by discrete ordinate method (DOM carried out with the Heat Transfer Module of Comsol Multiphysics® 4.4. The FFM showed a good agreement with the results of Monte Carlo method (MC and the six-flux model (SFM. Through this model, the LVREA is obtained, which is an important parameter to establish the reaction rate equation. In this study, the photocatalytic oxidation of benzyl alcohol to benzaldehyde was carried out, and the kinetic equation for this process was obtained. To perform the simulation, the commercial software COMSOL Multiphysics v. 4.4 was employed.

  10. Blanchability and sensory quality of large runner peanuts blanched in a radiant wall oven using infrared radiation.

    Kettler, Katrina; Adhikari, Koushik; Singh, Rakesh K

    2017-10-01

    The main factors behind the growing popularity of infrared radiation heating in food processing include its energy efficiency, food quality retention and process speed, as well as the simplicity of equipment. Infrared radiation was employed as an alternative heat treatment to the conventional hot air method used in peanut blanching. The present study aimed to investigate the application of infrared heating for blanching peanuts and determine their blanchability and sensory quality under various processing conditions. The total blanchabilities (expressed as a percentage of total blanched) of the infrared radiation trials (radiant wall oven) at 343 °C for 1.5 min, 316 °C for 1.5 min, 288 °C for 1.5 min and 343 °C for 1 min did not differ significantly compared to the hot air control trials (impingement oven) at 100 °C for 30 and 20 min. All infrared trials had significantly lower (P infrared samples demonstrated the possible initiation of oxidation for the conventionally blanched sample at 18 weeks of storage at 24 °C (room temperature), with no indication of oxidation in the infrared samples stored at the same temperature. Infrared radiation peanut blanching is a viable alternative to conventional hot air blanching because of the shorter process time and longer shelf-life, as evident from the sensory storage study. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  11. Optimal sizing and operation of energy storage systems considering long term assessment

    Gerardo Guerra

    2018-01-01

    Full Text Available This paper proposes a procedure for estimating the optimal sizing of Photovoltaic Generators and Energy Storage units when they are operated from the utility’s perspective. The goal is to explore the potential improvement on the overall operating conditions of the distribution system to which the Generators and Storage units will be connected. Optimization is conducted by means of a General Parallel Genetic Algorithm that seeks to maximize the technical benefits for the distribution system. The paper proposes an operation strategy for Energy Storage units based on the daily variation of load and generation; the operation strategy is optimized for an evaluation period of one year using hourly power curves. The construction of the yearly Storage operation curve results in a high-dimension optimization problem; as a result, different day-classification methods are applied in order to reduce the dimension of the optimization. Results show that the proposed approach is capable of producing significant improvements in system operating conditions and that the best performance is obtained when the day-classification is based on the similarity among daily power curves.

  12. Distributed Resource Energy Analysis and Management System (DREAMS) Development for Real-time Grid Operations

    Nakafuji, Dora [Hawaiian Electric Company, Honululu, HI (United States); Gouveia, Lauren [Hawaiian Electric Company, Honululu, HI (United States)

    2016-10-24

    This project supports development of the next generation, integrated energy management infrastructure (EMS) able to incorporate advance visualization of behind-the-meter distributed resource information and probabilistic renewable energy generation forecasts to inform real-time operational decisions. The project involves end-users and active feedback from an Utility Advisory Team (UAT) to help inform how information can be used to enhance operational functions (e.g. unit commitment, load forecasting, Automatic Generation Control (AGC) reserve monitoring, ramp alerts) within two major EMS platforms. Objectives include: Engaging utility operations personnel to develop user input on displays, set expectations, test and review; Developing ease of use and timeliness metrics for measuring enhancements; Developing prototype integrated capabilities within two operational EMS environments; Demonstrating an integrated decision analysis platform with real-time wind and solar forecasting information and timely distributed resource information; Seamlessly integrating new 4-dimensional information into operations without increasing workload and complexities; Developing sufficient analytics to inform and confidently transform and adopt new operating practices and procedures; Disseminating project lessons learned through industry sponsored workshops and conferences;Building on collaborative utility-vendor partnership and industry capabilities

  13. HVAC system operational strategies for reduced energy consumption in buildings with intermittent occupancy: The case of mosques

    Budaiwi, I.; Abdou, A.

    2013-01-01

    Highlights: • Proper operational zoning in the early design phase of mosques can lead to up to 30% reduction in the annual cooling energy. • Energy performance index of 71.0 kW h/m 2 yr for an insulated mosque can be realized with A/C proper intermitted operation. • 23% energy saving can be achieved when a properly oversized A/C is operated intermittently for 1 h during each prayer. • 13% reduction in cooling energy use can be achieved when A/C operation precedes worshippers’ occupancy in mosques. • Envelope insulation and A/C intermittent operation with proper operational zoning leads to more than 46% savings in energy. - Abstract: Mosques are places of worship for Muslims with unique functional requirements and operational characteristics. They are partially or fully occupied for about an hour for five intermittent periods during the day. In hot climates, maintaining indoor thermal comfort requires a considerable amount of energy that can be reduced by proper operational zoning and effective HVAC operation strategies. The objective of this paper is to investigate the impact of operational zoning and HVAC system intermittent operation strategies on the energy performance of mosques while thermal comfort is maintained. Energy simulation modeling is used for evaluating alternative zoning and HVAC operation strategies. Results indicate that up to 23% reduction in annual cooling energy is achieved by employing suitable HVAC operation strategy and system over-sizing, and 30% reduction is achieved by appropriate operational zoning. Comparing the cooling energy consumption of HVAC summer continuous operation of an un-insulated mosque with the consumption of the insulated mosque with properly oversized HVAC system operated for 1 h during each prayer, indicated that as much as 46% of cooling energy reduction can be achieved. Furthermore, utilizing proper operational zoning and HVAC operation strategies is expected to bring about an additional significant energy

  14. A coupled nuclear reactor thermal energy storage system for enhanced load following operation

    Alameri, Saeed A.; King, Jeffrey C.

    2013-01-01

    Nuclear power plants operate most economically at a constant power level, providing base load electric power. In an energy grid containing a high fraction of renewable power sources, nuclear reactors may be subject to significantly variable power demands. These variable power demands can negatively impact the effective capacity factor of the reactor and result in severe economic penalties. Coupling a nuclear reactor to a large thermal energy storage block will allow the reactor to better respond to variable power demands. In the system described in this paper, a Prismatic core Advanced High Temperature Reactor supplies constant power to a lithium chloride molten salt thermal energy storage block that provides thermal power as needed to a closed Brayton cycle energy conversion system. During normal operation, the thermal energy storage block stores thermal energy during the night for use in the times of peak demand during the day. In this case, the nuclear reactor stays at a constant thermal power level. After a loss of forced circulation, the reactor reaches a shut down state in less than half an hour and the average fuel, graphite and coolant temperatures remain well within the design limits over the duration of the transient, demonstrating the inherent safety of the coupled system. (author)

  15. Energy technology and opportunities for East-West co-operation

    Garribba, S.

    1991-01-01

    The private sector is probably the principal Western actor in Central and Eastern Europe. The accelerated political reforms in the East have improved the prospects for Western partners to invest in the energy sector and collaborate on energy technology development and transfer while taking advantage of the specific local benefits offered. These benefits are primarily found on the energy production side where the specific knowledge of the Western partner may be employed for the development of energy markets in the East. Conversely, the Central and Eastern European countries appear to be looking to co-operation with Western partners to provide them with access to capital, technology and organizational know-how, as well as, to Western markets. The primary long-term economic aim of Central and Eastern European governments must be to promote a market based economy. This requires not merely the definition of an official energy price system, but also the presence of legal and other institutions to establish property rights, civil contractual laws, trade policy and framework conditions for the free development of market forces and private enterprise. The IEA, International Energy Agency, as an example of the effectiveness of international co-operation, may be in the position to provide some assistance on technical and policy matters

  16. Energy expenditure and intake during Special Operations Forces field training in a jungle and glacial environment.

    Johnson, Caleb D; Simonson, Andrew J; Darnell, Matthew E; DeLany, James P; Wohleber, Meleesa F; Connaboy, Christopher

    2018-04-01

    The purpose of this study was to identify and compare energy requirements specific to Special Operations Forces in field training, in both cool and hot environments. Three separate training sessions were evaluated, 2 in a hot environment (n = 21) and 1 in a cool environment (n = 8). Total energy expenditure was calculated using doubly labeled water. Dietary intake was assessed via self-report at the end of each training mission day, and macronutrient intakes were calculated. Across the 3 missions, mean energy expenditure (4618 ± 1350 kcal/day) exceeded mean energy intake (2429 ± 838 kcal/day) by an average of 2200 kcal/day. Macronutrient intakes (carbohydrates (g/(kg·day body weight (bw)) -1 ) = 3.2 ± 1.2; protein (g/(kg·day bw) -1 ) = 1.3 ± 0.7; fat (g/(kg·day bw) -1 ) = 1.2 ± 0.7) showed inadequate carbohydrate and possibly protein intake across the study period, compared with common recommendations. Total energy expenditures were found to be similar between hot (4664 ± 1399 kcal/day) and cool (4549 ± 1221 kcal/day) environments. However, energy intake was found to be higher in the cool (3001 ± 900 kcal/day) compared with hot (2200 ± 711 kcal/day) environments. Based on the identified energy deficit, high variation in energy expenditures, and poor macronutrient intake, a greater attention to feeding practices during similar training scenarios for Special Operations Forces is needed to help maintain performance and health. The differences in environmental heat stress between the 2 climates/environments had no observed effect on energy expenditures, but may have influenced intakes.

  17. Stochastic Methods Applied to Power System Operations with Renewable Energy: A Review

    Zhou, Z. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Electric Reliability Council of Texas (ERCOT), Austin, TX (United States); Botterud, A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-08-01

    Renewable energy resources have been rapidly integrated into power systems in many parts of the world, contributing to a cleaner and more sustainable supply of electricity. Wind and solar resources also introduce new challenges for system operations and planning in terms of economics and reliability because of their variability and uncertainty. Operational strategies based on stochastic optimization have been developed recently to address these challenges. In general terms, these stochastic strategies either embed uncertainties into the scheduling formulations (e.g., the unit commitment [UC] problem) in probabilistic forms or develop more appropriate operating reserve strategies to take advantage of advanced forecasting techniques. Other approaches to address uncertainty are also proposed, where operational feasibility is ensured within an uncertainty set of forecasting intervals. In this report, a comprehensive review is conducted to present the state of the art through Spring 2015 in the area of stochastic methods applied to power system operations with high penetration of renewable energy. Chapters 1 and 2 give a brief introduction and overview of power system and electricity market operations, as well as the impact of renewable energy and how this impact is typically considered in modeling tools. Chapter 3 reviews relevant literature on operating reserves and specifically probabilistic methods to estimate the need for system reserve requirements. Chapter 4 looks at stochastic programming formulations of the UC and economic dispatch (ED) problems, highlighting benefits reported in the literature as well as recent industry developments. Chapter 5 briefly introduces alternative formulations of UC under uncertainty, such as robust, chance-constrained, and interval programming. Finally, in Chapter 6, we conclude with the main observations from our review and important directions for future work.

  18. Energy-optimised planning and operation of UPS installations. Guidelines for planners and operators; Energieoptimierte Planung und Betrieb von USV-Anlagen. Ein Leitfaden fuer Planer und Betreiber

    Neyer, A.; Schnyder, G.; Mauchle, P.

    2004-09-15

    This comprehensive brochure elaborated for the Swiss Federal Office of Energy (SFOE) is one of a set of nine reports that provide an overall review of the energy-efficiency of UPS systems. This brochure for planners and operators of UPS installations takes a look at how UPS installations can be optimised in order to reduce losses and to provide optimal operation as far as energy efficiency is concerned. The brochure explains the various types of UPS systems and their use and gives tips on ordering. Operational modes, load considerations, system configuration and specifications for putting to tender are looked at, as are the requirements to be placed on the systems for optimal operation. Basic rules for planning activities are quoted. Finally, rotating UPS installations and dynamic energy storage are briefly looked at. The paper is completed with checklists and a quality/energy-matrix.

  19. Prediction equation for estimating total daily energy requirements of special operations personnel.

    Barringer, N D; Pasiakos, S M; McClung, H L; Crombie, A P; Margolis, L M

    2018-01-01

    Special Operations Forces (SOF) engage in a variety of military tasks with many producing high energy expenditures, leading to undesired energy deficits and loss of body mass. Therefore, the ability to accurately estimate daily energy requirements would be useful for accurate logistical planning. Generate a predictive equation estimating energy requirements of SOF. Retrospective analysis of data collected from SOF personnel engaged in 12 different SOF training scenarios. Energy expenditure and total body water were determined using the doubly-labeled water technique. Physical activity level was determined as daily energy expenditure divided by resting metabolic rate. Physical activity level was broken into quartiles (0 = mission prep, 1 = common warrior tasks, 2 = battle drills, 3 = specialized intense activity) to generate a physical activity factor (PAF). Regression analysis was used to construct two predictive equations (Model A; body mass and PAF, Model B; fat-free mass and PAF) estimating daily energy expenditures. Average measured energy expenditure during SOF training was 4468 (range: 3700 to 6300) Kcal·d- 1 . Regression analysis revealed that physical activity level ( r  = 0.91; P  plan appropriate feeding regimens to meet SOF nutritional requirements across their mission profile.

  20. Thermoelectric energy harvesting system for demonstrating autonomous operation of a wireless sensor node enabled by a multipurpose interface

    Leicht, Joachim; Heilmann, Peter; Maurath, Dominic; Moranz, Christian; Manoli, Yiannos; Hehn, Thorsten; Li, Xiaoming; Thewes, Marcell; Scholl, Gerd

    2013-01-01

    This paper demonstrates the autonomous operation of a wireless sensor node exclusively powered by thermoelectric energy harvesting. Active operation of a wireless sensor system is demonstrated successfully by means of an on-line programmable emulation kit that enables various thermoelectric energy harvesting scenarios. Moreover, this emulation kit accomplishes autonomous wireless sensor node operation by interfacing a small-scaled thermogenerator via a CMOS integrated autonomous multipurpose energy harvesting interface circuit performing maximum power point tracking

  1. Influence of individual heat pumps on wind power integration – Energy system investments and operation

    Hedegaard, Karsten; Münster, Marie

    2013-01-01

    Highlights: • Individual heat pumps can significantly support the integration of wind power. • The heat pumps significantly reduce fuel consumption, CO 2 emissions, and costs. • Heat storages for the heat pumps can provide only moderate system benefits. • Main benefit of flexible heat pump operation is a lower peak/reserve capacity need. • Socio-economic feasibility only identified for some heat storages to some extent. - Abstract: Individual heat pumps are expected to constitute a significant electricity demand in future energy systems. This demand becomes flexible if investing in complementing heat storage capabilities. In this study, we analyse how the heat pumps can influence the integration of wind power by applying an energy system model that optimises both investments and operation, and covers various heat storage options. The Danish energy system by 2030 with around 50–60% wind power is used as a case study. Results show that the heat pumps, even without flexible operation, can contribute significantly to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO 2 emissions. Investments in heat storages can provide only moderate system benefits in these respects. The main benefit of the flexible heat pump operation is a reduced need for peak/reserve capacity, which is also crucial for the feasibility of the heat storages. Socio-economic feasibility is identified for control equipment enabling intelligent heat storage in the building structure and in existing hot water tanks. In contrast, investments in new heat accumulation tanks are not found competitive

  2. On the merger between Toshiba Corporation and Japan Atomic Energy Operation Co., Ltd. (reply report)

    1990-01-01

    The Nuclear Safety Commission made a careful examination regarding the merger between Toshiba Corporation and Japan Atomic Energy Operation Co., Ltd., (an issue submitted on August 16, 1989, for deliberation), and submitted a report to the prime minister. A study was carried out to determine whether the technical expertise possessed by Japan Atomic Energy Operation Co. would taken over properly by Toshiba Corporation, which would continue to exist after the merger. Results of the study revealed that the organization and technical experts existing at Japan Atomic Energy Operation Co. before the merger would properly incorporated into the existing system in Toshiba Corporation. Thus, it was confirmed that Toshiba Corporation after the merger would have technical capabilities required to install and operate nuclear reactors. The Atomic Nuclear Safety Commission started the above-mentioned study on the subject matter at the 32nd meeting, which was held on August 24, 1989, and reached the conclusion at the 34th meeting held on August 31, 1989. (N.K.)

  3. Operation of the LHC with Protons at High Luminosity and High Energy

    Papotti, Giulia; Alemany-Fernandez, Reyes; Crockford, Guy; Fuchsberger, Kajetan; Giachino, Rossano; Giovannozzi, Massimo; Hemelsoet, Georges-Henry; Höfle, Wolfgang; Jacquet, Delphine; Lamont, Mike; Nisbet, David; Normann, Lasse; Pojer, Mirko; Ponce, Laurette; Redaelli, Stefano; Salvachua, Belen; Solfaroli Camillocci, Matteo; Suykerbuyk, Ronaldus; Uythoven, Jan; Wenninger, Jorg

    2016-01-01

    In 2015 the Large Hadron Collider (LHC) entered the first year in its second long Run, after a 2-year shutdown that prepared it for high energy. The first two months of beam operation were dedicated to setting up the nominal cycle for proton-proton operation at 6.5 TeV/beam, and culminated with the first physics with 3 nominal bunches/ring at 13 TeV CoM on 3 June. The year continued with a stepwise intensity ramp up that allowed reaching 2244 bunches/ring for a peak luminosity of ~5·10³³ cm⁻²s^{−1} and a total of just above 4 fb-1 delivered to the high luminosity experiments. Beam operation was shaped by the high intensity effects, e.g. electron cloud and macroparticle-induced fast losses (UFOs), which on a few occasions caused the first beam induced quenches at high energy. This paper describes the operational experience with high intensity and high energy at the LHC, together with the issues that had to be tackled along the way.

  4. Energy Saving Melting and Revert Reduction Technology: Melting Efficiency in Die Casting Operations

    David Schwam

    2012-12-15

    This project addressed multiple aspects of the aluminum melting and handling in die casting operations, with the objective of increasing the energy efficiency while improving the quality of the molten metal. The efficiency of melting has always played an important role in the profitability of aluminum die casting operations. Consequently, die casters need to make careful choices in selecting and operating melting equipment and procedures. The capital cost of new melting equipment with higher efficiency can sometimes be recovered relatively fast when it replaces old melting equipment with lower efficiency. Upgrades designed to improve energy efficiency of existing equipment may be well justified. Energy efficiency is however not the only factor in optimizing melting operations. Melt losses and metal quality are also very important. Selection of melting equipment has to take into consideration the specific conditions at the die casting shop such as availability of floor space, average quantity of metal used as well as the ability to supply more metal during peaks in demand. In all these cases, it is essential to make informed decisions based on the best available data.

  5. Modeling and Operational Testing of an Isolated Variable Speed PMSG Wind Turbine with Battery Energy Storage

    BAROTE, L.

    2012-05-01

    Full Text Available This paper presents the modeling and operational testing of an isolated permanent magnet synchronous generator (PMSG, driven by a small wind turbine with a battery energy storage system during wind speed and load variations. The whole system is initially modeled, including the PMSG, the boost converter and the storage system. The required power for the connected loads can be effectively delivered and supplied by the proposed wind turbine and energy storage systems, subject to an appropriate control method. Energy storage devices are required for power balance and power quality in stand alone wind energy systems. The main purpose is to supply 230 V / 50 Hz domestic appliances through a single-phase inverter. The experimental waveforms, compared to the simulation results, show a good prediction of the electrical variable parameters. Furthermore, it can be seen that the results validate the stability of the supply.

  6. Operating results and simulations on a fuel cell for residential energy systems

    Hamada, Yasuhiro; Goto, Ryuichiro; Nakamura, Makoto; Kubota, Hideki; Ochifuji, Kiyoshi

    2006-01-01

    This paper describes the performance evaluation of a polymer electrolyte fuel cell (PEFC) prototype and demonstration experiments of the electric power and domestic hot water system using it from a pragmatic view-point. Three types of demonstration experiments were carried out applying standard electric power and hot water demands. It was shown that the primary energy reduction rate of this system as compared to the conventional system reached up to 24% under double daily start and stop (DSS) operation. The amount of primary energy reduction in experiments using the energy demand of a household in Sapporo in winter exceeded the experimental results of the standard energy demand, demonstrating that the effects of the introduction of a fuel cell in cold regions could be considerable, in particular, during the winter season

  7. Energy consumption during the building life cycle – influence of investment activities and operations

    Vytlačil Dalibor

    2018-01-01

    Full Text Available The paper describes the dynamic model of maintenance and investments of a building structure and HVAC systems. The aim of the research is finding the time dependent curve for energy consumption and also the cash flow that depends on the investments to energy saving arrangements and operations. The solution is based on the system dynamics method. The method makes possible to interconnect technical and economic parts of the problem. The main parameter in the model is the energy consumption in the building per floor square meter and year. This parameter is influenced by a deterioration of the building structure and the components of the active elements. The investments realized with the aim to decrease the energy consumption is another influence. The example of the computer simulation of the building parameters during the life cycle is presented in the paper.

  8. Evaluation of the energy required for constructing and operating a fusion power plant

    Buende, R.

    1982-09-01

    The energy required for constructing and operating a tokamak fusion power plant is appraised with respect to the energy output during the lifetime of the plant. A harvesting factor is deduced as a relevant figure of energetic merit and is used for a comparison between fusion, fission, and coal-fired power plants. Because fusion power plants involve considerable uncertainties the comparison is supplemented by a sensitivity analysis. In comparison with Light Water Reactor plants fusion power plants appear to be rather favourable in this respect. The energy required for providing the fuel is relatively low for fusion plants, thus overcompensating the considerable higher amount of energy necessary for constructing the fusion power plant. (orig.)

  9. A Study on the Efficient Operating Management of Atomic Energy Commission

    Yun, Sungwon; Chung, W. S.; Lee, D. S.; Park, S. J.

    2013-04-01

    This study aimed to provide professionals in humanities and social sciences, not only nuclear, with a place for communication by establishing a website of Atomic Energy Commission and people with a place for participation which help the nuclear policy reflect public opinions. By establishing the website of Atomic Energy Commission, experts (including those in humanities and social sciences) can suggest policy agenda and public opinions can be suggested through the place for public participation. Also the website should restrict on indiscreet search by separating sections only for experts and provide experts with a section for active and creative debate on nuclear policy. All the accessible meeting agenda and minutes have been chronologically organized and the findings of the committee have been announced to share with people concerning nuclear policy. In terms of the effective operation of Atomic Energy Commission, research has been conducted for standing committee, regular meeting, activating the commission through system change and expert committee in addition to support for the 2nd meeting of Atomic Energy Committee and the 31st Nuclear Expert Committee. Activation measures to improve the operating system of the commission is proposed as following; changing of the commission's chairman operating system, standing commission regular meeting, activation of subcommittee and expanding and diversifying of agenda

  10. Long-Pulse Operation and High-Energy Particle Confinement Study in ICRF Heating of LHD

    Mutoh, Takashi; Kumazawa, Ryuhei; Seki, Tetsuo

    2004-01-01

    Long-pulse operation and high-energy particle confinement properties were studied using ion cyclotron range of frequency (ICRF) heating for the Large Helical Device. For the minority-ion mode, ions with energies up to 500 keV were observed by concentrating the ICRF heating power near the plasma axis. The confinement of high-energy particles was studied using the power-modulation technique. This confirmed that the confinement of high-energy particles was better with the inward-shifted configuration than with the normal configuration. This behavior was the same for bulk plasma confinement. Long-pulse operation for more than 2 min was achieved during the experimental program in 2002. This was mainly due to better confinement of the helically trapped particles and accumulation of fewer impurities in the region of the plasma core, in conjunction with substantial hardware improvements. Currently, the plasma operation time is limited by an unexpected density rise due to outgassing from the chamber materials. The temperature of the local carbon plates of the divertor exceeded 400 deg, C, and a charge-coupled device camera observed the hot spots. The hot spot pattern was well explained by a calculation of the accelerated-particle orbits, and those accelerated particles came from outside the plasma near the ICRF antenna

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

    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.

  12. Planning and operating energy efficient factories; Energieeffiziente Fabriken planen und betreiben

    Mueller, Egon; Strauch, Joerg [Technische Univ. Chemnitz (Germany). Professur fuer Fabrikplanung und Fabrikbetrieb; Engelmann, Joerg [Volkswagen Sachsen GmbH, Zwickau (Germany). Werktechnik / Umweltplanung; Loeffler, Thomas [Technische Univ. Chemnitz (Germany). Professur fuer Fabrikplanung und Fabrikbetrieb; IREGIA e.V., Chemnitz (Germany)

    2009-07-01

    This book presents systematic approaches to developing energy saving potentials in the planning and operation of factories. The authors describe the drivers of the current energy debate and the state of the art in making factories energy efficient. They explain important principles that must be observed in considering factories as a system and in order to understand questions relating to energy. They have developed methods for finding appropriate energy-efficient solutions in factory planning. Detailed explanations are given on energy-relevant installations which require planning such as drives, compressed air systems or ventilation systems. The book presents methods and instruments for the analysis and evaluation of energy consumption which can be used for assessment purposes during the initial planning as well as for monitoring and influencing energy consumption during normal operation. Selected practical examples, notably from the automotive industry, serve to illustrate the material presented. The book is intended primarily for planning and production engineers in the piece goods industry as well as for students in related fields. [German] Das Buch zeigt auf, wie beim Planen und Betreiben von Fabriken systematisch Potenziale fuer Energieeinsparungen erschlossen werden koennen. Die Autoren beschreiben die Treiber der aktuellen Energiedebatte und den Status Quo der ''Energieeffizienten Fabrik''. Sie erlaeutern wichtige Grundlagen, um die Fabrik als System und energetische Zusammenhaenge zu verstehen. Eine von ihnen entwickelte Methodik hilft, bereits bei der Planung von Fabriken adaequate energieeffiziente Loesungen zu finden. Energierelevante Planungsobjekte wie elektrische Antriebe, Druckluft- oder Lueftungssysteme werden naeher erlaeutert. Fuer die Analyse und Bewertung des Energieverbrauchs werden Methoden und Instrumente vorgestellt, mit denen sowohl die Ausgangsituation bei der Planung beurteilt als auch der Energieverbrauch im

  13. Reliability of high-voltage pulse capacitors operating in large energy storages

    Kuchinskij, G.S.; Fedorova, V.S.; Shilin, O.V.

    1982-01-01

    To improve the reliability of pulse capacitors operating in capacitive energy storages, processes, resulting in break-down of capacitor insulation were investigated. A statistic model of failures was constructed and reliability of real capacitors, functioning at operating electric intensity Usub(oper) equal 70 kV/mm and at elevated intensity 90 kV/mm was calculated. Results of testing the IK50-ZU4 capacitor are given. The form of the capacitor service life distribution function was specified. To provide and confirm the assigned capacitor reliability, it is necessary to speed up tests at a higher voltage (1.3-1.5) Usub(oper). To improve the capacitor reliability, it is advisable to conduct acceptance tests, which include hold at increased constant voltage (1.3-1.5) Usub(oper) during 1-3 min and the effect of pulses of increased voltage (1.2-1.3) Usub(oper) with the pulse shape corresponding to operating conditions

  14. 78 FR 24192 - J.P. Morgan Ventures Energy Corp. v. Midwest Independent System Operator, Inc. PJM...

    2013-04-24

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL13-58-000] J.P. Morgan Ventures Energy Corp. v. Midwest Independent System Operator, Inc. PJM Interconnection, L.L.C.; Notice of Complaint Take notice that on April 10, 2013, J.P. Morgan Ventures Energy Corporation (JPMVEC or Complainant...

  15. Convexity of Energy-Like Functions: Theoretical Results and Applications to Power System Operations

    Dvijotham, Krishnamurthy [California Inst. of Technology (CalTech), Pasadena, CA (United States); Low, Steven [California Inst. of Technology (CalTech), Pasadena, CA (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-12

    Power systems are undergoing unprecedented transformations with increased adoption of renewables and distributed generation, as well as the adoption of demand response programs. All of these changes, while making the grid more responsive and potentially more efficient, pose significant challenges for power systems operators. Conventional operational paradigms are no longer sufficient as the power system may no longer have big dispatchable generators with sufficient positive and negative reserves. This increases the need for tools and algorithms that can efficiently predict safe regions of operation of the power system. In this paper, we study energy functions as a tool to design algorithms for various operational problems in power systems. These have a long history in power systems and have been primarily applied to transient stability problems. In this paper, we take a new look at power systems, focusing on an aspect that has previously received little attention: Convexity. We characterize the domain of voltage magnitudes and phases within which the energy function is convex in these variables. We show that this corresponds naturally with standard operational constraints imposed in power systems. We show that power of equations can be solved using this approach, as long as the solution lies within the convexity domain. We outline various desirable properties of solutions in the convexity domain and present simple numerical illustrations supporting our results.

  16. Realities of technical co-operation in the peaceful uses of nuclear energy

    Luxo, A.; Villaros, P.; Naudet, G.

    1978-01-01

    The decision to develop the peaceful uses of nuclear energy, especially the generation of electricity, is usually based - particularly in the developing countries - on numerous considerations, mainly of an economic and political nature. Since the resources of nuclear technology are concentrated, relatively speaking, in the advanced countries, the use of nuclear energy by countries that have decided to go nuclear is based on effective co-operation between the exporting and importing countries. The present paper is intended as an additional contribution to consideration of the realities of such co-operation. The authors first mention the specific features of nuclear development, after which they consider, on the basis thereof, the different forms of co-operation required for the transfer of technological knowhow, and the conditions determining the effectiveness of such transfer. This effectiveness is not linked solely to the competence of the personnel concerned or to smooth organizational procedures, but also to decisive socio-psychological factors. Having analysed these factors, the authors examine the salient problems of co-operation arising during the process of nuclear development. Co-operation ever better adapted to the purpose and taking human considerations into account will enable importing countries to acquire the nuclear knowhow that will promote their economic and social development. (author)

  17. Tool for optimal design and operation of hydrogen storage based autonomous energy systems

    Oberschachtsiek, B.; Lemken, D. [ZBT - Duisburg (Germany); Stark, M.; Krost, G. [Duisburg-Essen Univ. (Germany)

    2010-07-01

    Decentralized small scale electricity generation based on renewable energy sources usually necessitates decoupling of volatile power generation and consumption by means of energy storage. Hydrogen has proven as an eligible storage medium for mid- and long-term range, which - when indicated - can be reasonably complemented by accumulator short term storage. The selection of appropriate system components - sources, storage devices and the appertaining peripherals - is a demanding task which affords a high degree of freedom but, on the other hand, has to account for various operational dependencies and restrictions of system components, as well as for conduct of load and generation. An innovative tool facilitates the configuration and dimensioning of renewable energy based power supply systems with hydrogen storage paths, and allows for applying appropriate operation strategies. This tool accounts for the characteristics and performances of relevant power sources, loads, and types of energy storage, and also regards safety rules the energy system has to comply with. In particular, the tool is addressing small, detached and autonomous supply systems. (orig.)

  18. Ideal Operation of a Photovoltaic Power Plant Equipped with an Energy Storage System on Electricity Market

    Markku Järvelä

    2017-07-01

    Full Text Available There is no natural inertia in a photovoltaic (PV generator and changes in irradiation can be seen immediately at the output power. Moving cloud shadows are the dominant reason for fast PV power fluctuations taking place typically within a minute between 20 to 100% of the clear sky value roughly 100 times a day, on average. Therefore, operating a utility scale grid connected PV power plant is challenging. Currently, in many regions, renewable energy sources such as solar and wind receive feed-in tariffs that ensure a certain price for the energy. On the other hand, electricity markets operate on a supply-demand principle and a typical imbalance settlement period is one hour. This paper presents the energy, power and corresponding requirements for an energy storage system in a solar PV power plant to feed the power to the grid meeting the electricity spot markets practices. An ideal PV energy production forecast is assumed to be available to define reference powers of the system for the studied imbalance settlement periods. The analysis is done for three different PV system sizes using the existing irradiance measurements of the Tampere University of Technology solar PV power station research plant.

  19. Optimum Design and Operation of an HVAC Cooling Tower for Energy and Water Conservation

    Clemente García Cutillas

    2017-03-01

    Full Text Available The energy consumption increase in the last few years has contributed to developing energy efficiency policies in many countries, the main goal of which is decreasing CO 2 emissions. One of the reasons for this increment has been caused by the use of air conditioning systems due to new comfort standards. In that regard, cooling towers and evaporative condensers are presented as efficient devices that operate with low-level water temperature. Moreover, the energy consumption and the cost of the equipment are lower than other systems like air condensers at the same operation conditions. This work models an air conditioning system in TRNSYS software, the main elements if which are a cooling tower, a water-water chiller and a reference building. The cooling tower model is validated using experimental data in a pilot plant. The main objective is to implement an optimizing control strategy in order to reduce both energy and water consumption. Furthermore a comparison between three typical methods of capacity control is carried out. Additionally, different cooling tower configurations are assessed, involving six drift eliminators and two water distribution systems. Results show the influence of optimizing the control strategy and cooling tower configuration, with a maximum energy savings of 10.8% per story and a reduction of 4.8% in water consumption.

  20. Operational Benefits of Meeting California's Energy Storage Targets

    Eichman, Josh; Denholm, Paul; Jorgenson, Jennie; Helman, Udi

    2016-05-01

    In October 2013, the California Public Utilities Commission (CPUC) finalized procurement targets and other requirements to its jurisdictional utilities for a minimum of 1,325 MW of 'viable and cost-effective' energy storage systems by 2020. The goal of this study is to explore several aspects of grid operations in California and the Western Interconnection resulting from meeting the CPUC storage targets. We perform this analysis using a set of databases and grid simulation tools developed and implemented by the CPUC, the California Independent System Operator (CAISO), and the California Energy Commission (CEC) for the CPUC's Long-term Procurement Plan (LTPP). The 2014 version of this database contains information about generators, storage, transmission, and electrical demand, for California in the year 2024 for both 33 percent and 40 percent renewable energy portfolios. We examine the value of various services provided by energy storage in these scenarios. Sensitivities were performed relating to the services energy storage can provide, the capacity and duration of storage devices, export limitations, and negative price floor variations. Results show that a storage portfolio, as outlined by the CPUC, can reduce curtailment and system-wide production costs for 33 percent and 40 percent renewable scenarios.

  1. Energy operations and planning decision support for systems using weather forecast information

    Altalo, M.G.

    2004-01-01

    Hydroelectric utilities deal with uncertainties on a regular basis. These include uncertainties in weather, policy and markets. This presentation outlined regional studies to define uncertainty, sources of uncertainty and their affect on power managers, power marketers, power insurers and end users. Solutions to minimize uncertainties include better forecasting and better business processes to mobilize action. The main causes of uncertainty in energy operations and planning include uncaptured wind, precipitation and wind events. Load model errors also contribute to uncertainty in energy operations. This presentation presented the results of a 2002-2003 study conducted by the National Oceanic and Atmospheric Administration (NOAA) on the impact uncertainties in northeast energy weather forecasts. The study demonstrated the cost of seabreeze error on transmission and distribution. The impact of climate scale events were also presented along with energy demand implications. It was suggested that energy planners should incorporate climate change parameters into planning, and that models should include probability distribution forecasts and ensemble forecasting methods that incorporate microclimate estimates. It was also suggested that seabreeze, lake effect, fog, afternoon thunderstorms and frontal passage should be incorporated into forecasts. tabs., figs

  2. Mobile operators have set ambitious targets – Is it possible to boost network capacity while reducing its energy consumption?

    Micallef, Gilbert; Mogensen, Preben; Scheck, Hans-Otto

    2012-01-01

    While operators have to upgrade the capacity of their networks, they have committed themselves to reduce their CO2 emissions, partly by reducing their energy consumption. This article investigates the challenges faced by operators and quantifies, through a number of case studies, the impact...... the possible savings by adopting an energy-efficient capacity evolution together with an equipment replacement and site upgrade strategy. Results show that network operators can get relatively close to their targets, with energy reductions of up to 40% noted. While this can be improved further through software...... based energy saving features, further CO2 emissions can be offset through carbon-neutral energy sources....

  3. Decomposition analysis of energy consumption for an freeway during its operation period: A case study for Guangdong, China

    Li, DuoQi; Wang, DuanYi

    2016-01-01

    Freeways have become the main subject of energy conservation reviews in China because of their large energy consumption. Decomposition analysis has been widely applied in energy consumption studies. However, most studies have only analyzed the driving forces of energy consumption on the national level, and seldom at smaller levels, e.g. for departments like toll stations and maintenance centers. Based on the characteristics of the freeway operation period, this paper serves as a preliminary attempt at applying the logarithm mean Divisia index method I on the department level to analyze the energy consumption of freeways during the operation period. To elucidate the evolution of energy consumption during the operational period, the logarithm mean Divisia index analysis was performed to disentangle the energy consumption based on a real case in Guangdong from 2005 to 2013. The analyses establish that the traffic volume influences energy consumption. The results show that some departments can influence the total energy consumption. For example, the tunnels and toll stations are key factors that influence the total energy consumption of the whole road. The decomposition in the departments revealed that energy efficiency improvements caused by the use of alternate materials and energy-saving technologies mainly contributed to energy conservation. - Highlights: • Decomposition model was used to analyze energy consumption of freeway management. • This attempt finds the impact of traffic volume on management energy consumption. • Tunnels and toll stations mainly affect the management energy consumption. • Using alternate materials and energy-saving technology improved energy efficiency.

  4. Application of LBB to high energy piping systems in operating PWR

    Swamy, S.A.; Bhowmick, D.C. [Westinghouse Nuclear Technology Division, Pittsburgh, PA (United States)

    1997-04-01

    The amendment to General Design Criterion 4 allows exclusion, from the design basis, of dynamic effects associated with high energy pipe rupture by application of leak-before-break (LBB) technology. This new approach has resulted in substantial financial savings to utilities when applied to the Pressurized Water Reactor (PWR) primary loop piping and auxiliary piping systems made of stainless steel material. To date majority of applications pertain to piping systems in operating plants. Various steps of evaluation associated with the LBB application to an operating plant are described in this paper.

  5. Capital and operating cost estimates for high temperature superconducting magnetic energy storage

    Schoenung, S.M.; Meier, W.R.; Fagaly, R.L.; Heiberger, M.; Stephens, R.B.; Leuer, J.A.; Guzman, R.A.

    1992-01-01

    Capital and operating costs have been estimated for mid-scale (2 to 200 Mwh) superconducting magnetic energy storage (SMES) designed to use high temperature superconductors (HTS). Capital costs are dominated by the cost of superconducting materials. Operating costs, primarily for regeneration, are significantly reduced for HTS-SMES in comparison to low temperature, conventional systems. This cost component is small compared to other O and M and capital components, when levelized annual costs are projected. In this paper, the developments required for HTS-SMES feasibility are discussed

  6. Energy study of rail passenger transportation. Volume 2. Description of operating systems. Final report

    Henderson, C.; Ellis, H. T.; Wilhelm, J. P.

    1979-08-01

    The rail passenger systems of the US are described in terms of selected physical, operating, and economic characteristics, and relates services rendered to energy usage and costs. Rail passenger transportation exists in 4 distinct forms: intercity railroads, suburban railroads, heavy-rail transit, and light-rail transit. Each form varies in technical equipment, design of facilities, operating practices, size of systems. Specific data for the national rail passenger network and the Boston, Chicago, Cleveland, New York, Philadelphia, Pittsburgh, and San Francisco regions and the Washington Metropolitan area transit authority are presented.

  7. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  8. An independent safety assessment of Department of Energy nuclear reactor facilities: Procedures, operations and maintenance

    Toto, G.; Lindgren, A.J.

    1981-02-01

    The 1979 accident at the Three Mile Island commercial nuclear power plant has led to a number of studies of nuclear reactors, in both the public and private sectors. One of these is that of the Department of Energy's (DOE) Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee, which has outlined tasks for assessment of 13 reactors owned by DOE and operated by contractors. This report covers one of the tasks, the assessment of procedures, operations, and maintenance at the DOE reactor facilities, based on a review of actual documents used at the reactor sites

  9. State-of-The-Art of Modeling Methodologies and Optimization Operations in Integrated Energy System

    Zheng, Zhan; Zhang, Yongjun

    2017-08-01

    Rapid advances in low carbon technologies and smart energy communities are reshaping future patterns. Uncertainty in energy productions and demand sides are paving the way towards decentralization management. Current energy infrastructures could not meet with supply and consumption challenges, along with emerging environment and economic requirements. Integrated Energy System(IES) whereby electric power, natural gas, heating couples with each other demonstrates that such a significant technique would gradually become one of main comprehensive and optimal energy solutions with high flexibility, friendly renewables absorption and improving efficiency. In these global energy trends, we summarize this literature review. Firstly the accurate definition and characteristics of IES have been presented. Energy subsystem and coupling elements modeling issues are analyzed. It is pointed out that decomposed and integrated analysis methods are the key algorithms for IES optimization operations problems, followed by exploring the IES market mechanisms. Finally several future research tendencies of IES, such as dynamic modeling, peer-to-peer trading, couple market design, sare under discussion.

  10. Environmental Monitoring Techniques and Equipment related to the installation and operation of Marine Energy Conversion Systems

    Scanu, Sergio; Carli, Filippo Maria; Piermattei, Viviana; Bonamano, Simone; Paladini de Mendoza, Francesco; Marcelli, Marco; Peviani, Maximo Aurelio; Dampney, Keith; Norris, Jennifer

    2015-01-01

    Results of activities under project Marine Renewables Infrastructure Network for Emerging Energy Technologies (MaRINET) are reported, which led to DEMTE, a database, created on the basis of standardized monitoring of the marine environment during installation, operation and decommissioning of Marine Energy Conversion Systems. Obtained with the consortium partners’ available techniques and equipment, the database shows that such instruments cover all identified marine environmental compartments, despite the lack of underwater vehicles and the reduced skills in using satellite technologies. These weaknesses could be overcome by an accurate planning of equipment, techniques and knowledge sharing. The approach here presented also leads to an effective analysis even in non-marine contexts

  11. Economic evaluation of operational concepts for electrolysers with high proportions of renewable energies

    Michaelis, Julia; Wietschel, Martin

    2015-01-01

    This article examines different modes of electrolyzers in two future scenarios of the German energy system. It turns out that hydrolyzers need a high utilization to pay for themselves. An economic operation in 2030 in the scenario of moderate expansion of renewable energies is not possible. At strong expansion the investment is profitable when high revenues from secondary control power provision can be achieved. Generally it is clear that the secondary control power provision and also the direct sales of hydrogen in industry or in the transport sector allows higher revenues than the storage and reconversion. [de

  12. Energy and environmental performance assessment of R744 booster supermarket refrigeration systems operating in warm climates

    Gullo, Paride; Elmegaard, Brian; Cortella, Giovanni

    2016-01-01

    This paper presents a theoretical comparison among different commercial refrigeration systems in terms of annual energy consumption and environmental impact. Eight configurations were studied: a R744/R134a cascade refrigeration system (baseline), a conventional and an improved R744 booster system...... as on the running modes of a conventional European supermarket. A transition zone, which occurred between sub critical and transcritical operations, was adopted.The results showed that all the enhanced configurations may achieve a comparable energy saving to the one of the baseline in both the selected locations...

  13. Comparison of radiant and convective cooling of office room: effect of workstation layout

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Rezgals, Lauris

    2014-01-01

    and compared. The room was furnished with two workstations, two laptops and two thermal manikins resembling occupants. Two heat load levels, design (65 W/m2) and usual (39 W/m2), were generated by adding heat from warm panels simulating solar radiation. Two set-ups were studied: occupants sitting......The impact of heat source location (room layout) on the thermal environment generated in a double office room with four cooling ventilation systems - overhead ventilation, chilled ceiling with overhead ventilation, active chilled beam and active chilled beam with radiant panels was measured...

  14. Three dimensional modelling and numerical analysis of super-radiant harmonic emission in FEL (optical klystron)

    Gover, A.; Friedman, A.; Luccio, A.

    1986-09-01

    A full 3-D Analysis of super-radiant (bunched electron) free electron harmonic radiation is presented. A generalized form of the FEL pendulum equation was derived and numerically solved. Both spectral and phasor formulation were developed to treat the radiation in the time domain. In space the radiation field is expanded in terms of either a set of free space discrete modes or plane waves. The numerical solutions reveal some new distinctly 3-D effects to which we provide a physical explanation. 12 refs., 9 figs., 5 tabs

  15. Perceived air quality, thermal comfort, and SBS symptoms at low air temperature and increased radiant temperature

    Toftum, Jørn; Reimann, Gregers Peter; Foldbjerg, P.

    2002-01-01

    source present at the low temperature. To maintain overall thermal neutrality, the low air temperature was partly compensated for by individually controlled radiant heating, and partly by allowing subjects to modify clothing insulation. A reduction of the air temperature from 23 deg.C to 18 deg.......C suggested an improvement of the perceived air quality, while no systematic effect on symptom intensity was observed. The overall indoor environment was evaluated equally acceptable at both temperatures due to local thermal discomfort at the low air temperature....

  16. Failure Investigation of Radiant Platen Superheater Tube of Thermal Power Plant Boiler

    Ghosh, D.; Ray, S.; Mandal, A.; Roy, H.

    2015-04-01

    This paper highlights a case study of typical premature failure of a radiant platen superheater tube of 210 MW thermal power plant boiler. Visual examination, dimensional measurement and chemical analysis, are conducted as part of the investigations. Apart from these, metallographic analysis and fractography are also conducted to ascertain the probable cause of failure. Finally it has been concluded that the premature failure of the super heater tube can be attributed to localized creep at high temperature. The corrective actions has also been suggested to avoid this type of failure in near future.

  17. Literarily -radiant

    Halvorsen, Finn

    2008-01-01

    The article discusses radiation emissions from various every day appliances such as mobile telephones, wireless technologic aids, networks, radios and television sets. The health risks are mentioned (tk)

  18. Distributed Energy Systems Integration and Demand Optimization for Autonomous Operations and Electric Grid Transactions

    Ghatikar, Girish [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Greenlots, San Francisco, CA (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Center for Energy and Innovation Technologies (Austria); Yin, Rongxin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Zhenhua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-11-29

    Distributed power systems in the U.S. and globally are evolving to provide reliable and clean energy to consumers. In California, existing regulations require significant increases in renewable generation, as well as identification of customer-side distributed energy resources (DER) controls, communication technologies, and standards for interconnection with the electric grid systems. As DER deployment expands, customer-side DER control and optimization will be critical for system flexibility and demand response (DR) participation, which improves the economic viability of DER systems. Current DER systems integration and communication challenges include leveraging the existing DER and DR technology and systems infrastructure, and enabling optimized cost, energy and carbon choices for customers to deploy interoperable grid transactions and renewable energy systems at scale. Our paper presents a cost-effective solution to these challenges by exploring communication technologies and information models for DER system integration and interoperability. This system uses open standards and optimization models for resource planning based on dynamic-pricing notifications and autonomous operations within various domains of the smart grid energy system. It identifies architectures and customer engagement strategies in dynamic DR pricing transactions to generate feedback information models for load flexibility, load profiles, and participation schedules. The models are tested at a real site in California—Fort Hunter Liggett (FHL). Furthermore, our results for FHL show that the model fits within the existing and new DR business models and networked systems for transactive energy concepts. Integrated energy systems, communication networks, and modeling tools that coordinate supply-side networks and DER will enable electric grid system operators to use DER for grid transactions in an integrated system.

  19. Determination of the wind power systems load to achieve operation in the maximum energy area

    Chioncel, C. P.; Tirian, G. O.; Spunei, E.; Gillich, N.

    2018-01-01

    This paper analyses the operation of the wind turbine, WT, in the maximum power point, MPP, by linking the load of the Permanent Magnet Synchronous Generator, PMSG, with the wind speed value. The load control methods at wind power systems aiming an optimum performance in terms of energy are based on the fact that the energy captured by the wind turbine significantly depends on the mechanical angular speed of the wind turbine. The presented control method consists in determining the optimal mechanical angular speed, ωOPTIM, using an auxiliary low power wind turbine, WTAUX, operating without load, at maximum angular velocity, ωMAX. The method relies on the fact that the ratio ωOPTIM/ωMAX has a constant value for a given wind turbine and does not depend on the time variation of the wind speed values.

  20. The kinetic energy operator for distance-dependent effective nuclear masses: Derivation for a triatomic molecule.

    Khoma, Mykhaylo; Jaquet, Ralph

    2017-09-21

    The kinetic energy operator for triatomic molecules with coordinate or distance-dependent nuclear masses has been derived. By combination of the chain rule method and the analysis of infinitesimal variations of molecular coordinates, a simple and general technique for the construction of the kinetic energy operator has been proposed. The asymptotic properties of the Hamiltonian have been investigated with respect to the ratio of the electron and proton mass. We have demonstrated that an ad hoc introduction of distance (and direction) dependent nuclear masses in Cartesian coordinates preserves the total rotational invariance of the problem. With the help of Wigner rotation functions, an effective Hamiltonian for nuclear motion can be derived. In the derivation, we have focused on the effective trinuclear Hamiltonian. All necessary matrix elements are given in closed analytical form. Preliminary results for the influence of non-adiabaticity on vibrational band origins are presented for H 3 + .

  1. Environmental Monitoring Plan United States Department of Energy Richland Operations Office. Revision 2

    NONE

    1997-11-10

    This Environmental Monitoring Plan was prepared for the US Department of Energy`s (DOE`s) Richland Operations Office (RL) to implement the requirements of DOE Order 5400.1. According to the Order, each DOE site, facility, or activity that uses, generates, releases, or manages significant pollutants or hazardous materials shall prepare a written environmental monitoring plan covering two major activities: (1) effluent monitoring and (2) environmental surveillance. The plan is to contain information discussing the rationale and design criteria for the monitoring programs, sampling locations and schedules, quality assurance requirements, program implementation procedures, analytical procedures, and reporting requirements. The plan`s purpose is to assist DOE in the management of environmental activities at the Hanford Site and to help ensure that operations on the site are conducted in an environmentally safe and sound manner.

  2. Optimal Technology Investment and Operation in Zero-Net-Energy Buildings with Demand Response

    Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; Hirohisa, Aki; Lai, Judy

    2009-01-01

    The US Department of Energy has launched the Zero-Net-Energy (ZNE) Commercial Building Initiative (CBI) in order to develop commercial buildings that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge energy-efficient technologies and meet their remaining energy needs through on-site renewable energy generation. We examine how such buildings may be implemented within the context of a cost- or carbon-minimizing microgrid that is able to adopt and operate various technologies, such as photovoltaic (PV) on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and passive/demand-response technologies. We use a mixed-integer linear program (MILP) that has a multi-criteria objective function: the minimization of a weighted average of the building's annual energy costs and carbon/CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the CBI. Using a nursing home in northern California and New York with existing tariff rates and technology data, we find that a ZNE building requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve ZNE. For comparison, we analyze a nursing home facility in New York to examine the effects of a flatter tariff structure and different load profiles. It has trouble reaching ZNE status and its load reductions as well as efficiency measures need to be more effective than those in the CA case

  3. Optimization of Design Parameters and Operating Conditions of Electrochemical Capacitors for High Energy and Power Performance

    Ike, Innocent S.; Sigalas, Iakovos; Iyuke, Sunny E.

    2017-03-01

    Theoretical expressions for performance parameters of different electrochemical capacitors (ECs) have been optimized by solving them using MATLAB scripts as well as via the MATLAB R2014a optimization toolbox. The performance of the different kinds of ECs under given conditions was compared using theoretical equations and simulations of various models based on the conditions of device components, using optimal values for the coefficient associated with the battery-kind material ( K BMopt) and the constant associated with the electrolyte material ( K Eopt), as well as our symmetric electric double-layer capacitor (EDLC) experimental data. Estimation of performance parameters was possible based on values for the mass ratio of electrodes, operating potential range ratio, and specific capacitance of electrolyte. The performance of asymmetric ECs with suitable electrode mass and operating potential range ratios using aqueous or organic electrolyte at appropriate operating potential range and specific capacitance was 2.2 and 5.56 times greater, respectively, than for the symmetric EDLC and asymmetric EC using the same aqueous electrolyte, respectively. This enhancement was accompanied by reduced cell mass and volume. Also, the storable and deliverable energies of the asymmetric EC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 12.9 times greater than those of the symmetric EDLC using aqueous electrolyte, again with reduced cell mass and volume. The storable energy, energy density, and power density of the asymmetric EDLC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 5.56 times higher than for a similar symmetric EDLC using aqueous electrolyte, with cell mass and volume reduced by a factor of 1.77. Also, the asymmetric EDLC with the same type of electrode and suitable electrode mass ratio, working potential range ratio, and proper organic electrolyte

  4. Performance evaluation of operational energy use in refurbishment, reuse, and conservation of heritage buildings for optimum sustainability

    O.K. Akande

    2016-09-01

    Full Text Available The operational phase of a building project has increasingly gained importance with their energy performance becoming valuable and determining their operational excellence. In most heritage building projects (HBPs, the operational energy use aspects are less considered, and a systematic way of analyzing their energy performance following project delivery is often lacking. The aim of this study is to evaluate the operational performance of refurbishment and reuse of UK listed church projects. The objective is to assess the operational energy use with a view to optimizing their sustainable performance. The methodology includes eight selected case study buildings refurbished and converted for multipurpose use. The case study approach provided qualitative insights into how the study contributes to a more structured requirements for energy management in HBPs with specific attention to energy-efficient building operations. The findings show the need to focus on fundamental areas of operational management (i.e. by developing and implementing more focused policy on operational energy performance of heritage buildings to minimize the energy required to operate them. The challenges of implementing changes in operational energy performance improvement of heritage buildings are addressed in the form of recommendations that could lead to real results. The study concludes that leveraging these areas requires commitment from all heritage building stakeholders because they all have substantial roles in harmonizing the requirement for the project׳s sustainability and not just the building operators. Meanwhile, baseline project planning, periodic updating, monitoring, and managing the energy use pattern are suggested as measures that could greatly facilitate better energy performance to optimizing their sustainable reuse compared with the traditional approach of trying to improve their thermal performance.

  5. Ideal Operation of a Photovoltaic Power Plant Equipped with an Energy Storage System on Electricity Market

    Markku Järvelä; Seppo Valkealahti

    2017-01-01

    There is no natural inertia in a photovoltaic (PV) generator and changes in irradiation can be seen immediately at the output power. Moving cloud shadows are the dominant reason for fast PV power fluctuations taking place typically within a minute between 20 to 100% of the clear sky value roughly 100 times a day, on average. Therefore, operating a utility scale grid connected PV power plant is challenging. Currently, in many regions, renewable energy sources such as solar and wind receive fee...

  6. The low-energy electron accelerator LEA for pilot scale operations

    Mehnert, R.; Klenert, P.

    1990-01-01

    An electron processor equipped with a linear cathode has been developed for use in pilot scale radiation processing. It can provide electron beam powers up to 6 kW at energies between 150 and 200 keV. The design of some components of the processor system and first results of its operation as part of a pilot unit for curing of furniture elements will be discussed. (author)

  7. Optimal Operation of Micro-grids Considering the Uncertainties of Demand and Renewable Energy Resources Generation

    Malek Jasemi

    2016-11-01

    Full Text Available Nowadays, due to technical and economic reasons, the distributed generation (DG units are widely connected to the low and medium voltage network and created a new structure called micro-grid. Renewable energies (especially wind and solar based DGs are one of the most important generations units among DG units. Because of stochastic behavior of these resources, the optimum and safe management and operation of micro-grids has become one of the research priorities for researchers. So, in this study, the optimal operation of a typical micro-grid is investigated in order to maximize the penetration of renewable energy sources with the lowest operation cost with respect to the limitations for the load supply and the distributed generation resources. The understudy micro-grid consists of diesel generator, battery, wind turbines and photovoltaic panels. The objective function comprises of fuel cost, start-up cost, spinning reserve cost, power purchasing cost from the upstream grid and the sales revenue of the power to the upstream grid. In this paper, the uncertainties of demand, wind speed and solar radiation are considered and the optimization will be made by using the GAMS software and mixed integer planning method (MIP. Article History: Received May 21, 2016; Received in revised form July 11, 2016; Accepted October 15, 2016; Available online How to Cite This Article: Jasemi, M.,  Adabi, F., Mozafari, B., and Salahi, S. (2016 Optimal Operation of Micro-grids Considering the Uncertainties of Demand and Renewable Energy Resources Generation, Int. Journal of Renewable Energy Development, 5(3,233-248. http://dx.doi.org/10.14710/ijred.5.3.233-248

  8. Resolving issues at the Department of Energy/Oak Ridge operations facilities

    Row, T.H.; Adams, W.D.

    1988-01-01

    The development of the US Department of Energy Oak Ridge Operations Office's model for waste management and its application in the Oak Ridge Reservation are discussed. The concept simply stated is to assure that all stakeholders in waste management decisions have the opportunity to be participants from the first step. The paper discusses the advisory committees involved in the process, subcontracting support, college and university relation, technology demonstrations and planning, other federal agency interaction, and the model meeting

  9. Practical operation strategies for pumped hydroelectric energy storage (PHES) utilising electricity price arbitrage

    Connolly, D.; Lund, H.; Finn, P.; Mathiesen, B.V.; Leahy, M.

    2011-01-01

    In this paper, three practical operation strategies (24Optimal, 24Prognostic, and 24Hsitrocial) are compared to the optimum profit feasible for a PHES facility with a 360 MW pump, 300 MW turbine, and a 2 GWh storage utilising price arbitrage on 13 electricity spot markets. The results indicate that almost all (∼97%) of the profits can be obtained by a PHES facility when it is optimised using the 24Optimal strategy developed, which optimises the energy storage based on the day-ahead electricity prices. However, to maximise profits with the 24Optimal strategy, the day-ahead electricity prices must be the actual prices which the PHES facility is charged or the PHES operator must have very accurate price predictions. Otherwise, the predicted profit could be significantly reduced and even become a loss. Finally, using the 24Optimal strategy, the PHES profit can surpass the annual investment repayments required. However, over the 5-year period investigated (2005-2009) the annual profit from the PHES facility varied by more than 50% on five out of six electricity markets considered. Considering the 40-year lifetime of PHES, even with low investment costs, a low interest rate, and a suitable electricity market, PHES is a risky investment without a more predictable profit. - Highlights: → Electricity generators typically operate on a market, including energy storage. → This paper assesses how energy storage can maximise its profits on a market. → Four operating strategies are assessed on 13 markets using a case study.→ One operating strategy achieves 97% of the profits feasible.→ However, the profit varies a lot depending on the market and capital costs.

  10. Analysis of electric energy consumption of automatic milking systems in different configurations and operative conditions.

    Calcante, Aldo; Tangorra, Francesco M; Oberti, Roberto

    2016-05-01

    Automatic milking systems (AMS) have been a revolutionary innovation in dairy cow farming. Currently, more than 10,000 dairy cow farms worldwide use AMS to milk their cows. Electric consumption is one of the most relevant and uncontrollable operational cost of AMS, ranging between 35 and 40% of their total annual operational costs. The aim of the present study was to measure and analyze the electric energy consumption of 4 AMS with different configurations: single box, central unit featuring a central vacuum system for 1 cow unit and for 2 cow units. The electrical consumption (daily consumption, daily consumption per cow milked, consumption per milking, and consumption per 100L of milk) of each AMS (milking unit + air compressor) was measured using 2 energy analyzers. The measurement period lasted 24h with a sampling frequency of 0.2Hz. The daily total energy consumption (milking unit + air compressor) ranged between 45.4 and 81.3 kWh; the consumption per cow milked ranged between 0.59 and 0.99 kWh; the consumption per milking ranged between 0.21 and 0.33 kWh; and the consumption per 100L of milk ranged between 1.80 to 2.44 kWh according to the different configurations and operational contexts considered. Results showed that AMS electric consumption was mainly conditioned by farm management rather than machine characteristics/architectures. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Modeling of biomass-to-energy supply chain operations: Applications, challenges and research directions

    Mafakheri, Fereshteh; Nasiri, Fuzhan

    2014-01-01

    Reducing dependency on fossil fuels and mitigating their environmental impacts are among the most promising aspects of utilizing renewable energy sources. The availability of various biomass resources has made it an appealing source of renewable energy. Given the variability of supply and sources of biomass, supply chains play an important role in the efficient provisioning of biomass resources for energy production. This paper provides a comprehensive review and classification of the excising literature in modeling of biomass supply chain operations while linking them to the wider strategic challenges and issues with the design, planning and management of biomass supply chains. On that basis, we will present an analysis of the existing gaps and the potential future directions for research in modeling of biomass supply chain operations. - Highlights: • An extensive review of biomass supply chain operations management models presented in the literature is provided. • The models are classified in line with biomass supply chain activities from harvesting to conversion. • The issues surrounding biomass supply chains are investigated manifesting the need to novel modeling approaches. • Our gap analysis has identified a number of existing shortcomings and opportunities for future research

  12. The Operation Consequence of Nuclear Energy to Environment; Konsekuensi Pengoperasian Tenaga Nuklir terhadap Lingkungan

    Suhariyono, Gatot; Sutarman, [Center for Research and Development of Radiation Safety and Nuclear Biomedicine, (Indonesia)

    2003-08-15

    Objective of the paper is to give information the operation consequence of nuclear energy to environment, so that expected as organizer of PLTN can anticipate or depress as minimum as possible radiology impact to the radiation workers and society in general, and also socialization that operation of nuclear energy do not give the negative impact, if conducted its control to environment seriously. Parts of which it is important to know from this paper are : one. Estimate of equivalent dose of collective effective in a normal condition is the operation cycle for nuclear energy at worker and local or regional resident 10, 100 or 10.000 next years. 2. Equivalent dose of global collective effective is for various the radiation sources. 3. Estimate of dose per cap ut annual of nuclear electric power until year 2500. 4. Aspect of non-radiology is to cooler system, usage of farm, dismissal of chemistry, advantage of hot water waste, its effect to fish, benthos, plankton, vegetation, animal and preparation of nuclear emergency.

  13. Operational energy in the life cycle of residential dwellings: The experience of Spain and Colombia

    Ortiz, Oscar; Castells, Francesc; Sonnemann, Guido

    2010-01-01

    Life Cycle Assessment (LCA) has been applied within the residential building sector of two buildings, one in each a developed (Spain) and a developing (Colombia) country. The main goal of this paper involves the environmental loads and also brings together the operational energy for activities during the operation phase such as HVAC, domestic hot water, electrical appliances, cooking and illumination. The present research compares two real scenarios: Situation 1, where 100% of the dwelling's energy is supplied with electricity only and Situation 2, where dwellings can be operated with natural gas plus electricity. The results for the environmental impacts using natural gas plus electricity show that of the Spanish environmental impacts air conditioning had the highest impact with approximately 27-42% due to the electricity used to power it. In Colombian results showed that electrical appliances had the highest environmental impacts in the same order of magnitude with approximately 60% and cooking had the best reduction of emissions due to the use of natural gas, from 10% down to less than 2%. The origin of the energy source used in each Country plays an important role to minimize environmental impacts, as was demonstrated by the environmental impacts of its use in Colombia where 78% of the electricity came from hydroelectric plants whereas in Spain it is more mixed, fossil fuels represented 55%, nuclear 18% and wind 9%. In summary, LCA has been applied because this methodology supports the decision making to concern environmental sustainability.

  14. A multi evaporator desalination system operated with thermocline energy for future sustainability

    Shahzad, Muhammad Wakil

    2017-05-05

    All existing commercial seawater desalination processes, i.e. thermally-driven and membrane-based reverse osmosis (RO), are operated with universal performance ratios (UPR) varying up to 105, whilst the UPR for an ideal or thermodynamic limit (TL) of desalination is at 828. Despite slightly better UPRs for the RO plants, all practical desalination plants available, hitherto, operate at only less than 12% of the TL, rendering them highly energy intensive and unsustainable for future sustainability. More innovative desalination methods must be sought to meet the needs of future sustainable desalination and these methods should attain an upper UPR bound of about 25 to 30% of the TL. In this paper, we examined the efficacy of a multi-effect distillation (MED) system operated with thermocline energy from the sea; a proven desalination technology that can exploit the narrow temperature gradient of 20°C all year round created between the warm surface seawater and the cold-seawater at depths of about 300–600m. Such a seawater thermocline (ST)-driven MED system, simply called the ST-MED process, has the potential to achieve up to 2 folds improvement in desalination efficiency over the existing methods, attaining about 18.8% of the ideal limit. With the major energy input emanated from the renewable solar, the ST-MED is truly a “green desalination” method of low global warming potential, best suited for tropical coastal shores having bathymetry depths of 300m or more.

  15. A Simple Operating Strategy of Small-Scale Battery Energy Storages for Energy Arbitrage under Dynamic Pricing Tariffs

    Enrico Telaretti

    2015-12-01

    Full Text Available Price arbitrage involves taking advantage of an electricity price difference, storing electricity during low-prices times, and selling it back to the grid during high-prices periods. This strategy can be exploited by customers in presence of dynamic pricing schemes, such as hourly electricity prices, where the customer electricity cost may vary at any hour of day, and power consumption can be managed in a more flexible and economical manner, taking advantage of the price differential. Instead of modifying their energy consumption, customers can install storage systems to reduce their electricity bill, shifting the energy consumption from on-peak to off-peak hours. This paper develops a detailed storage model linking together technical, economic and electricity market parameters. The proposed operating strategy aims to maximize the profit of the storage owner (electricity customer under simplifying assumptions, by determining the optimal charge/discharge schedule. The model can be applied to several kinds of storages, although the simulations refer to three kinds of batteries: lead-acid, lithium-ion (Li-ion and sodium-sulfur (NaS batteries. Unlike literature reviews, often requiring an estimate of the end-user load profile, the proposed operation strategy is able to properly identify the battery-charging schedule, relying only on the hourly price profile, regardless of the specific facility’s consumption, thanks to some simplifying assumptions in the sizing and the operation of the battery. This could be particularly useful when the customer load profile cannot be scheduled with sufficient reliability, because of the uncertainty inherent in load forecasting. The motivation behind this research is that storage devices can help to lower the average electricity prices, increasing flexibility and fostering the integration of renewable sources into the power system.

  16. Energy models for generation planning and midterm operation of hydrothermal power systems

    Amthauer, E

    1981-01-01

    The aims of generation planning and midterm operation of a power system are reliable and economical load coverage at any moment. For solving some of the planning tasks, it is advantageous to use energy models, if a large amount of power is installed in hydro-storage plants. Energy models apply the probability of load coverage in a given period as a quantitative measure for a power system's reliability provided the availability of the transmission network is given. Reliability may be influenced by installing new plants (longterm) or by committing the existing plants in a particular fashion. An evaluation of these activities makes it possible to determine decisions which optimize a given object function. In this thesis, energy models for the Swiss hydrothermal power system are derived and tested by simulation. For this utility, energy supply during the emptying period of the storage plants in winter is of special interest. Therefore, the criteria for generation planning are derived by analysing the distribution functions of future energy balances in winter periods. The committment of the existing plants and energy exchange with other utilities in a straight following winter period are planned by means of a sequential decision process. It is shown how strategies for these planning tasks are found with the models. Those model parameters, having the highest influence on reliable and economical load coverage are extracted by means of sensitivity analysis.

  17. Optimal synthesis and operation of advanced energy supply systems for standard and domotic home

    Buoro, Dario; Casisi, Melchiorre; Pinamonti, Piero; Reini, Mauro

    2012-01-01

    Highlights: ► Definition of an optimization model for a home energy supply system. ► Optimization of the energy supply system for standard and domotic home. ► Strong improvement can be achieved adopting the optimal system in standard and domotic home. ► The improvements are consistent if supply side and demand side strategies are applied together. ► Solutions with internal combustion engines are less sensible to market price of electricity and gas. - Abstract: The paper deals with the optimization of an advanced energy supply systems for two dwellings: a standard home and an advanced domotic home, where some demand side energy saving strategies have been implemented. In both cases the optimal synthesis, design and operation of the whole energy supply system have been obtained and a sensitivity analysis has been performed, by introducing different economic constraints. The optimization model is based on a Mixed Integer Linear Program (MILP) and includes different kinds of small-scale cogenerators, geothermal heat pumps, boilers, heat storages, solar thermal and photovoltaic panels. In addition, absorption machines, supplied with cogenerated heat, can be used instead of conventional electrical chiller to face the cooling demand. The aim of the analysis is to address the question if advanced demand strategies and supply strategies have to be regarded as alternatives, or if they have to be simultaneously applied, in order to obtain the maximum energy and economic benefit.

  18. Pressure retarded osmosis for energy production: membrane materials and operating conditions.

    Kim, H; Choi, J-S; Lee, S

    2012-01-01

    Pressure retarded osmosis (PRO) is a novel membrane process to produce energy. PRO has the potential to convert the osmotic pressure difference between fresh water (i.e. river water) and seawater to electricity. Moreover, it can recover energy from highly concentrated brine in seawater desalination. Nevertheless, relatively little research has been undertaken for fundamental understanding of the PRO process. In this study, the characteristics of the PRO process were examined using a proof-of-concept device. Forward osmosis (FO), reverse osmosis (RO), and nanofiltration (NF) membranes were compared in terms of flux rate and concentration polarization ratio. The results indicated that the theoretical energy production by PRO depends on the membrane type as well as operating conditions (i.e. back pressure). The FO membrane had the highest energy efficiency while the NF membrane had the lowest efficiency. However, the energy production rate was low due to high internal concentration polarization (ICP) in the PRO membrane. This finding suggests that the control of the ICP is essential for practical application of PRO for energy production.

  19. Investment, firm value, and risk for a system operator balancing energy grids

    Dockner, Engelbert J.; Kucsera, Dénes; Rammerstorfer, Margarethe

    2013-01-01

    With the liberalization of energy markets integrated energy companies have separated into entities that specialize in production and/or transmission of energy. Transmission of energy requires balancing the grid to guarantee system security, which is performed by the (independent) system operator (SO). When the SO faces stochastic demand, grid balancing has sizeable consequences on current and future profits, and hence, on firm value and firm risk. We explore these value and risk consequences with and without an investment option to expand transmission capacity. We show that firm value consists of the value of the transmission capacity in place plus the value of a short put and a short call option that are the result of the SO's balancing actions. Firm risk without investment option is non-linear and determined by the short option positions. It is decreasing with increasing energy demand. The existence of an option to expand transmission capacity increases firm value and firm risk. - Highlights: ► Grid balancing under stochastic demand affect current and future revenues, and firm value and firm risk. ► Balancing firm value consists of the value of the transmission capacity plus the value of a short strangle. ► Firm risk without investment option is determined by the short strangle and decreasing with increasing energy demand. ► The existence of an expansion option implies that transmission capacity increases firm value and firm risk

  20. Potential pollution prevention and waste minimization for Department of Energy operations

    Griffin, J.; Ischay, C.; Kennicott, M.; Pemberton, S.; Tull, D.

    1995-10-01

    With the tightening of budgets and limited resources, it is important to ensure operations are carried out in a cost-effective and productive manner. Implementing an effective Pollution Prevention strategy can help to reduce the costs of waste management and prevent harmful releases to the environment. This document provides an estimate of the Department of Energy's waste reduction potential from the implementation of Pollution Prevention opportunities. A team of Waste Minimization and Pollution Prevention professionals was formed to collect the data and make the estimates. The report includes a list of specific reduction opportunities for various waste generating operations and waste types. A generic set of recommendations to achieve these reduction opportunities is also provided as well as a general discussion of the approach and assumptions made for each waste generating operation

  1. Self-energy operator for an electron in an external Coulomb potential. II

    Hostler, L.

    1988-01-01

    Relativistic Coulomb Sturmian matrix elements of the operator Oequivalentln(1-rho)/rho, rho = -[πx(1+iσ)xπ]/m 2 , in terms of which the self-energy operator for an electron in an external Coulomb potential has been expressed, are studied. The operator O is dealt with on a term by term basis in a Sturmian expansion. Each term of the Sturmian expansion is separated into a part whose matrix elements are analytic functions of Zα, plus a remainder evaluated in closed form by use of the Cauchy residue theorem. All ignorance about the matrix element of the general term in the Sturmian expansion of O is thereby placed entirely in the analytic part, for which an explicit integral representation is derived

  2. High Voltage Gain Dual Active Bridge Converter with an Extended Operation Range for Renewable Energy Systems

    Zhang, Zhe; Tomas Manez, Kevin; Yudi, Xiao

    2018-01-01

    Bridge (P2DAB) converter, i.e. low-voltage (LV) side parallel and high-voltage (HV) side series, is proposed to achieve high voltage gain and low current stress over switching devices and transformer windings. Given the unmodified P2DAB power stage, by regulating the phase-shift angle between......Developing bidirectional dc-dc converters has become a critical research topic and gains more and more attention in recent years due to the extensive applications of smart grids with energy storages, hybrid and electrical vehicles and dc microgrids. In this paper, a Partial Parallel Dual Active...... the paralleled active bridges, the power equations and voltage gain are then modified, and therefore the operation range can be extended effectively. The operating principles of the proposed converter and its power characteristics under various operation modes are studied, and the design constraints...

  3. Optimal operation strategies of compressed air energy storage (CAES) on electricity spot markets with fluctuating prices

    Lund, Henrik; Salgi, Georges; Elmegaard, Brian

    2009-01-01

    on electricity spot markets by storing energy when electricity prices are low and producing electricity when prices are high. In order to make a profit on such markets, CAES plant operators have to identify proper strategies to decide when to sell and when to buy electricity. This paper describes three...... plants will not be able to achieve such optimal operation, since the fluctuations of spot market prices in the coming hours and days are not known. Consequently, two simple practical strategies have been identified and compared to the results of the optimal strategy. This comparison shows that...... independent computer-based methodologies which may be used for identifying the optimal operation strategy for a given CAES plant, on a given spot market and in a given year. The optimal strategy is identified as the one which provides the best business-economic net earnings for the plant. In practice, CAES...

  4. Operational Benefits of Meeting California's Energy Storage Targets

    Eichman, Josh [National Renewable Energy Lab. (NREL), Golden, CO (United States); Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Helman, Udi [Helman Analytics, San Francisco, CA (United States)

    2015-12-18

    In October 2013, the California Public Utilities Commission (CPUC) finalized procurement targets and other requirements to its jurisdictional utilities for a minimum of 1,325 MW of 'viable and cost-effective' energy storage systems by 2020. The goal of this study is to explore several aspects of grid operations in California and the Western Interconnection resulting from meeting the CPUC storage targets. We perform this analysis using a set of databases and grid simulation tools developed and implemented by the CPUC, the California Independent System Operator (CAISO), and the California Energy Commission (CEC) for the CPUC's Long-term Procurement Plan (LTPP). The 2014 version of this database contains information about generators, storage, transmission, and electrical demand, for California in the year 2024 for both 33% and 40% renewable energy portfolios. We examine the value of various services provided by energy storage in these scenarios. Sensitivities were performed relating to the services energy storage can provide, the capacity and duration of storage devices, export limitations, and negative price floor variations. Results show that a storage portfolio, as outlined by the CPUC, can reduce curtailment and system-wide production costs for 33% and 40% renewable scenarios. A storage device that can participate in energy and ancillary service markets provides the grid with the greatest benefit; the mandated storage requirement of 1,325 MW was estimated to reduce the total cost of production by about 78 million per year in the 33% scenario and 144 million per year in the 40% scenario. Much of this value is derived from the avoided start and stop costs of thermal generators and provision of ancillary services. A device on the 2024 California grid and participating in only ancillary service markets can provide the system with over 90% of the value as the energy and ancillary service device. The analysis points to the challenge of new storage

  5. Energy and economic analysis of an ICE-based variable speed-operated micro-cogenerator

    Caresana, Flavio; Bartolini, Carlo Maria [Universita Politecnica delle Marche, Dipartimento di Energetica, Via Brecce Bianche, Ancona (AN) 60100 (Italy); Brandoni, Caterina [Universita Telematica e-Campus, Ingegneria Energetica, Via Isimbardi 10, Novedrate (CO) 22060 (Italy); Feliciotti, Petro [Universita Politecnica delle Marche, Dipartimento di Ingegneria Informatica, Gestionale e dell' Automazione, Via Brecce Bianche, Ancona (AN) 60100 (Italy)

    2011-03-15

    Micro-combined heat and power (CHP) systems are a key resource to meet the EUCO{sub 2} reduction agreed in the Kyoto Protocol. In the near future they are likely to spread significantly through applications in the residential and service sectors, since they can provide considerably higher primary energy efficiencies than plants generating electricity and heat separately. A 28 kW{sub e} natural gas, automotive-derived internal combustion engine CHP system was modeled with a view to comparing constant and variable speed operation modes. Besides their energy performances, the paper addresses the major factors involved in their economic evaluation and describes a method to assess their economic feasibility. Typical residential and service sector applications were chosen as test cases and the results discussed in terms of energy performances and of profitability. They showed that interesting savings can be obtained with respect to separate generation, and that they are higher for the household application in variable speed operating conditions. In fact the plant's energy performance is greatly enhanced by the possibility, for any given power, to regulate the engine's rotational speed. From the economic viewpoint, despite the higher initial cost of the variable speed concept, the system involves a shorter pay-back period and ensures greater profit. (author)

  6. Novel electrical energy storage system based on reversible solid oxide cells: System design and operating conditions

    Wendel, C. H.; Kazempoor, P.; Braun, R. J.

    2015-02-01

    Electrical energy storage (EES) is an important component of the future electric grid. Given that no other widely available technology meets all the EES requirements, reversible (or regenerative) solid oxide cells (ReSOCs) working in both fuel cell (power producing) and electrolysis (fuel producing) modes are envisioned as a technology capable of providing highly efficient and cost-effective EES. However, there are still many challenges and questions from cell materials development to system level operation of ReSOCs that should be addressed before widespread application. This paper presents a novel system based on ReSOCs that employ a thermal management strategy of promoting exothermic methanation within the ReSOC cell-stack to provide thermal energy for the endothermic steam/CO2 electrolysis reactions during charging mode (fuel producing). This approach also serves to enhance the energy density of the stored gases. Modeling and parametric analysis of an energy storage concept is performed using a physically based ReSOC stack model coupled with thermodynamic system component models. Results indicate that roundtrip efficiencies greater than 70% can be achieved at intermediate stack temperature (680 °C) and elevated stack pressure (20 bar). The optimal operating condition arises from a tradeoff between stack efficiency and auxiliary power requirements from balance of plant hardware.

  7. Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

    Ferin, G.; Bantignies, C.; Le Khanh, H.; Flesch, E.; Nguyen-Dinh, A.

    2015-12-01

    Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations.

  8. IMPACT OF THE COLD END OPERATING CONDITIONS ON ENERGY EFFICIENCY OF THE STEAM POWER PLANTS

    Slobodan Laković

    2010-01-01

    Full Text Available The conventional steam power plant working under the Rankine Cycle and the steam condenser as a heat sink and the steam boiler as a heat source have the same importance for the power plant operating process. Energy efficiency of the coal fired power plant strongly depends on its turbine-condenser system operation mode. For the given thermal power plant configuration, cooling water temperature or/and flow rate change generate alterations in the condenser pressure. Those changes have great influence on the energy efficiency of the plant. This paper focuses on the influence of the cooling water temperature and flow rate on the condenser performance, and thus on the specific heat rate of the coal fired plant and its energy efficiency. Reference plant is working under turbine-follow mode with an open cycle cooling system. Analysis is done using thermodynamic theory, in order to define heat load dependence on the cooling water temperature and flow rate. Having these correlations, for given cooling water temperature it is possible to determine optimal flow rate of the cooling water in order to achieve an optimal condensing pressure, and thus, optimal energy efficiency of the plant. Obtained results could be used as useful guidelines in improving existing power plants performances and also in design of the new power plants.

  9. Energy and economic analysis of an ICE-based variable speed-operated micro-cogenerator

    Caresana, Flavio; Brandoni, Caterina; Feliciotti, Petro; Bartolini, Carlo Maria

    2011-01-01

    Micro-combined heat and power (CHP) systems are a key resource to meet the EUCO 2 reduction agreed in the Kyoto Protocol. In the near future they are likely to spread significantly through applications in the residential and service sectors, since they can provide considerably higher primary energy efficiencies than plants generating electricity and heat separately. A 28 kW e natural gas, automotive-derived internal combustion engine CHP system was modeled with a view to comparing constant and variable speed operation modes. Besides their energy performances, the paper addresses the major factors involved in their economic evaluation and describes a method to assess their economic feasibility. Typical residential and service sector applications were chosen as test cases and the results discussed in terms of energy performances and of profitability. They showed that interesting savings can be obtained with respect to separate generation, and that they are higher for the household application in variable speed operating conditions. In fact the plant's energy performance is greatly enhanced by the possibility, for any given power, to regulate the engine's rotational speed. From the economic viewpoint, despite the higher initial cost of the variable speed concept, the system involves a shorter pay-back period and ensures greater profit.

  10. Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

    Ferin, G; Bantignies, C; Khanh, H Le; Flesch, E; Nguyen-Dinh, A

    2015-01-01

    Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations. (paper)

  11. Optimal Constant DC Link Voltage Operation of aWave Energy Converter

    Mats Leijon

    2013-04-01

    Full Text Available This article proposes a simple and reliable damping strategy for wave powerfarm operation of small-scale point-absorber converters. The strategy is based on passiverectification onto a constant DC-link, making it very suitable for grid integration of the farm.A complete model of the system has been developed in Matlab Simulink, and uses real sitedata as input. The optimal constant DC-voltage is evaluated as a function of the significantwave height and energy period of the waves. The total energy output of the WEC is derivedfor one year of experimental site data. The energy output is compared for two cases, onewhere the optimal DC-voltage is determined and held constant at half-hour basis throughoutthe year, and one where a selected value of the DC-voltage is kept constant throughout theyear regardless of sea state.

  12. Operation of Grid -Connected Lithium-Ion Battery Energy Storage System for Primary Frequency Regulation

    Stroe, Daniel Loan; Knap, Vaclav; Swierczynski, Maciej Jozef

    2017-01-01

    Because of their characteristics, which have been continuously improved during the last years, Lithium ion batteries were proposed as an alternative viable solution to present fast-reacting conventional generating units to deliver the primary frequency regulation service. However, even though...... there are worldwide demonstration projects where energy storage systems based on Lithium-ion batteries are evaluated for such applications, the field experience is still very limited. In consequence, at present there are no very clear requirements on how the Lithium-ion battery energy storage systems should...... be operated while providing frequency regulation service and how the system has to re-establish its SOC once the frequency event has passed. Therefore, this paper aims to investigate the effect on the lifetime of the Lithium-ion batteries energy storage system of various strategies for re...

  13. Suggested Operation Grid-Connected Lithium-Ion Battery Energy Storage System for Primary Frequency Regulation

    Stroe, Daniel Ioan; Knap, Vaclav; Swierczynski, Maciej Jozef

    2015-01-01

    Because of their characteristics, which have been continuously improved during the last years, Lithium ion batteries were proposed as an alternative viable solution to present fast-reacting conventional generating units to deliver the primary frequency regulation service. However, even though...... there are worldwide demonstration projects where energy storage systems based on Lithium-ion batteries are evaluated for such applications, the field experience is still very limited. In consequence, at present there are no very clear requirements on how the Lithium-ion battery energy storage systems should...... be operated while providing frequency regulation service and how the system has to re-establish its SOC once the frequency event has passed. Therefore, this paper aims to investigate the effect on the lifetime of the Lithium-ion batteries energy storage system of various strategies for re...

  14. Stand-Alone Photovoltaic System Operation with Energy Management and Fault Tolerant

    Jmashidpour, Ehsan; Poure, Philippe; Gholipour, E.; Saadate, Shahrokh

    2017-01-01

    This paper presents a stand-alone photovoltaic (PV) system with a fault tolerant operation capability. An energy management method is provided to keep the balance between produced and consumed energy instantaneously. As the storage element, an Ultra-Capacitor (UC) pack is used for facing high frequency variation of the load/source, and batteries are in charge of slow load /source variations. A Maximum Power Point Tracking (MPPT) algorithm is applied to control the boost converter of the PV source to achieve the maximum power. In order to improve the micro-grid service continuity and reliability, a fast fault diagnosis method based on the converter current shape for PV source is applied. Finally, the validity of the proposed energy management and the fault diagnosis method is confirmed by the simulation and experimental results. (author)

  15. Solar radiation and cooling load calculation for radiant systems: Definition and evaluation of the Direct Solar Load

    Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco

    2010-01-01

    The study of the influence of solar radiation on the built environment is a basic issue in building physics and currently it is extremely important because glazed envelopes are widely used in contemporary architecture. In the present study, the removal of solar heat gains by radiant cooling systems...... is investigated. Particular attention is given to the portion of solar radiation converted to cooling load, without taking part in thermal absorption phenomena due to the thermal mass of the room. This specific component of the cooling load is defined as the Direct Solar Load. A simplified procedure to correctly...... calculate the magnitude of the Direct Solar Load in cooling load calculations is proposed and it is implemented with the Heat Balance method and the Radiant Time Series method. The F ratio of the solar heat gains directly converted to cooling load, in the case of a low thermal mass radiant ceiling...

  16. Use of local convective and radiant cooling at warm environment: effect on thermal comfort and perceived air quality

    Melikov, Arsen Krikor; Duszyk, Marcin; Krejcirikova, Barbora

    2012-01-01

    The effect of four local cooling devices (convective, radiant and combined) on thermal comfort and perceived air quality reported by 24 subjects at 28 ˚C and 50% RH was studied. The devices studied were: (1) desk cooling fan, (2) personalized ventilation providing clean air, (3) two radiant panels...... and (4) two radiant panels with one panel equipped with small fans. A reference condition without cooling was tested as well. The response of the subjects to the exposed conditions was collected by computerized questionnaires. The cooling devices significantly (pthermal comfort...... compared to without cooling. The acceptability of the thermal environment was similar for all cooling devices. The acceptability of air movement and PAQ increased when the local cooling methods were used. The best results were achieved with personalized ventilation and cooling fan. The improvement in PAQ...

  17. Research on Utilizing a Multivariate Feedback Algorithm to Maintain Stable Operation of Variable Energy Electron Accelerators

    Van Ausdeln, L.A.; Cordes, G.A.; Haskell, K.J.; Jones, J.L.

    2002-01-01

    Measurements performed utilizing particle accelerators rely on the stability and reproducibility of the accelerator operation, most notably for beam flux (beam current) and beam energy. This can be vital when the measurements rely on previous calibrations performed to establish a standard on which to base the end result of the measurement. The authors have designed a monitoring and control virtual instrument (VI) based on National Instruments LabVIEW TM which calls external modeling code that is written in a standard programming language. The LabVIEWTM virtual instrument allows the user to monitor multiple accelerator parameters while permitting user control of the most important four of these parameters which determine machine operation. The external modeling code, the Advanced Data Validation and Verification System (ADVVS), incorporates as a kernel the Universal Process Model (UPM) software from Triant Technologies, Inc. The kernel executes the accelerator modeling function based on previously acquired history data of the relevant parameters for accelerator operation for conditions of interest. This history data is stored as a reference set prior to subsequent operation. During accelerator operation, 11 accelerator parameters are input to ADVVS from the LabVIEW TM virtual instrument. The ADVVS uses the reference files to predict the eleven parameter values that would normally be expected for optimal accelerator operation. The set of 11 model values is the nearest model state. This multivariate modeling approach presented two principal advantages: 1. The ADVVS allowed rapid detection of anomalous accelerator behavior variant from normal accelerator behavior recorded in the reference set of the kernel. 2. The ADVVS presented a methodology to incrementally tune the accelerator back to optimal operation, thus maintaining highly stable and reproducible operation. In the future, this methodology may also be utilized to tune the accelerator initially or move

  18. Unlocking High-Salinity Desalination with Cascading Osmotically Mediated Reverse Osmosis: Energy and Operating Pressure Analysis.

    Chen, Xi; Yip, Ngai Yin

    2018-02-20

    Current practice of using thermally driven methods to treat hypersaline brines is highly energy-intensive and costly. While conventional reverse osmosis (RO) is the most efficient desalination technique, it is confined to purifying seawater and lower salinity sources. Hydraulic pressure restrictions and elevated energy demand render RO unsuitable for high-salinity streams. Here, we propose an innovative cascading osmotically mediated reverse osmosis (COMRO) technology to overcome the limitations of conventional RO. The innovation utilizes the novel design of bilateral countercurrent reverse osmosis stages to depress the hydraulic pressure needed by lessening the osmotic pressure difference across the membrane, and simultaneously achieve energy savings. Instead of the 137 bar required by conventional RO to desalinate 70 000 ppm TDS hypersaline feed, the highest operating pressure in COMRO is only 68.3 bar (-50%). Furthermore, up to ≈17% energy saving is attained by COMRO (3.16 kWh/m 3 , compared to 3.79 kWh/m 3 with conventional RO). When COMRO is employed to boost the recovery of seawater desalination to 70% from the typical 35-50%, energy savings of up to ≈33% is achieved (2.11 kWh/m 3 , compared to 3.16 kWh/m 3 with conventional RO). Again, COMRO can operate at a moderate hydraulic pressure of 80 bar (25% lower than 113 bar of conventional RO). This study highlights the encouraging potential of energy-efficient COMRO to access unprecedented high recovery rates and treat hypersaline brines at moderate hydraulic pressures, thus extending the capabilities of membrane-based technologies for high-salinity desalination.

  19. Effect of radiant heat transfer on the performance of high temperature heat exchanger

    Mori, Yasuo; Hijikata, Kunio; Yamada, Yukio

    1975-01-01

    The development of high temperature gas-cooled reactors is motivated by the consideration of the application of nuclear heat for industrial uses or direct steelmaking and chemical processes. For these purposes, reliable and efficient heat exchangers should be developed. This report analyzes the effect of radiant heat transfer on the performance of high temperature heat exchangers. The heat transfer model is as follows: the channel composed with two parallel adiabatic walls is divided with one parallel plate between the walls. Non-radiative fluid flows in the two separated channels in opposite direction. Heat transfer equations for this system were obtained, and these equations were solved by some approximate method and numerical analysis. The effect of radiation on heat transfer became larger as the radiant heat transfer between two walls was larger. In the heat exchangers of counter flow type, the thermal efficiency is controlled with three parameters, namely radiation-convection parameter, Stanton number and temperature difference. The thermal efficiency was larger with the increase of these parameters. (Iwase, T.)

  20. Numerical Simulation of the Thermal Process in a W-Shape Radiant Tube Burner

    Wang, Yi; Li, Jiyong; Zhang, Lifeng; Ling, Haitao; Li, Yanlong

    2014-07-01

    In the current work, three-dimensional mathematical models were developed for the heat transfer and combustion in a W-shape radiant tube burner (RTB) and were solved using Fluent software (ANSYS Inc., Canonsburg, PA). The standard k- ɛ model, nonpremixed combustion model, and the discrete ordinate model were used for the modeling of turbulence, combustion, and radiant heat transfer, respectively. In addition, the NO x postprocessor was used for the prediction of the NO emission. A corresponding experiment was performed for the validation of mathematical models. The details of fluid flow, heat transfer, and combustion in the RTB were investigated. Moreover, the effect of the air/fuel ratio (A/F) and air staging on the performance of RTB was studied with the reference indexes including heat efficiency, maximum temperature difference on shell wall, and NO emission at the outlet. The results indicated that a low speed zone formed in the vicinity of the combustion chamber outlet, and there were two relative high-temperature zones in the RTB, one in combustion chamber that favored the flame stability and the other from the main flame in the RTB. The maximum temperature difference was 95.48 K. As the A/F increased, the temperature increased first and then decreased. As the ratio of the primary to secondary air increased, the recirculation zone at the outlet of combustion chamber shrank gradually to disappear, and the flame length was longer and the temperature in flame decreased correspondingly.

  1. Radiative heat exchange of a meteor body in the approximation of radiant heat conduction

    Pilyugin, N.N.; Chernova, T.A.

    1986-01-01

    The problem of the thermal and dynamic destruction of large meteor bodies moving in planetary atmospheres is fundamental for the clarification of optical observations and anomalous phenomena in the atmosphere, the determination of the physicochemical properties of meteoroids, and the explanation of the fall of remnants of large meteorites. Therefore, it is important to calculate the coefficient of radiant heat exchange (which is the determining factor under these conditions) for large meteor bodies as they move with hypersonic velocities in an atmosphere. The solution of this problem enables one to find the ablation of a meteorite during its aerodynamic heating and to determine the initial conditions for the solution of problems of the breakup of large bodies and their subsequent motion and ablation. Hypersonic flow of an inviscid gas stream over an axisymmetric blunt body is analyzed with allowance for radiative transfer in a thick-thin approximation. The gas-dynamic problem of the flow of an optically thick gas over a large body is solved by the method of asymptotic joined expansions, using a hypersonic approximation and local self-similarity. An equation is obtained for the coefficient of radiant heat exchange and the peculiarities of such heat exchange for meteor bodies of large size are noted

  2. High-temperature process heat reactor with solid coolant and radiant heat exchange

    Alekseev, A.M.; Bulkin, Yu.M.; Vasil'ev, S.I.

    1984-01-01

    The high temperature graphite reactor with the solid coolant in which heat transfer is realized by radiant heat exchange is described. Neutron-physical and thermal-technological features of the reactor are considered. The reactor vessel is made of sheet carbon steel in the form of a sealed rectangular annular box. The moderator is a set of graphite blocks mounted as rows of arched laying Between the moderator rows the solid coolant annular layings made of graphite blocks with high temperature nuclear fuel in the form of coated microparticles are placed. The coolant layings are mounted onto ring movable platforms, the continuous rotation of which is realizod by special electric drives. Each part of the graphite coolant laying consecutively passes through the reactor core neutron cut-off zones and technological zone. In the core the graphite is heated up to the temperature of 1350 deg C sufficient for effective radiant heat transfer. In the neutron cut-off zone the chain reaction and further graphite heating are stopped. In the technological zone the graphite transfers the accumulated heat to the walls of technological channels in which the working medium moves. The described reactor is supposed to be used in nuclear-chemical complex for ammonia production by the method of methane steam catalytic conversion

  3. Energy efficiency estimation of a steam powered LNG tanker using normal operating data

    Sinha Rajendra Prasad

    2016-01-01

    Full Text Available A ship’s energy efficiency performance is generally estimated by conducting special sea trials of few hours under very controlled environmental conditions of calm sea, standard draft and optimum trim. This indicator is then used as the benchmark for future reference of the ship’s Energy Efficiency Performance (EEP. In practice, however, for greater part of operating life the ship operates in conditions which are far removed from original sea trial conditions and therefore comparing energy performance with benchmark performance indicator is not truly valid. In such situations a higher fuel consumption reading from the ship fuel meter may not be a true indicator of poor machinery performance or dirty underwater hull. Most likely, the reasons for higher fuel consumption may lie in factors other than the condition of hull and machinery, such as head wind, current, low load operations or incorrect trim [1]. Thus a better and more accurate approach to determine energy efficiency of the ship attributable only to main machinery and underwater hull condition will be to filter out the influence of all spurious and non-standard operating conditions from the ship’s fuel consumption [2]. The author in this paper identifies parameters of a suitable filter to be used on the daily report data of a typical LNG tanker of 33000 kW shaft power to remove effects of spurious and non-standard ship operations on its fuel consumption. The filtered daily report data has been then used to estimate actual fuel efficiency of the ship and compared with the sea trials benchmark performance. Results obtained using data filter show closer agreement with the benchmark EEP than obtained from the monthly mini trials . The data filtering method proposed in this paper has the advantage of using the actual operational data of the ship and thus saving cost of conducting special sea trials to estimate ship EEP. The agreement between estimated results and special sea trials EEP is

  4. Solar energy prediction and verification using operational model forecasts and ground-based solar measurements

    Kosmopoulos, P.G.; Kazadzis, S.; Lagouvardos, K.; Kotroni, V.; Bais, A.

    2015-01-01

    The present study focuses on the predictions and verification of these predictions of solar energy using ground-based solar measurements from the Hellenic Network for Solar Energy and the National Observatory of Athens network, as well as solar radiation operational forecasts provided by the MM5 mesoscale model. The evaluation was carried out independently for the different networks, for two forecast horizons (1 and 2 days ahead), for the seasons of the year, for varying solar elevation, for the indicative energy potential of the area, and for four classes of cloud cover based on the calculated clearness index (k_t): CS (clear sky), SC (scattered clouds), BC (broken clouds) and OC (overcast). The seasonal dependence presented relative rRMSE (Root Mean Square Error) values ranging from 15% (summer) to 60% (winter), while the solar elevation dependence revealed a high effectiveness and reliability near local noon (rRMSE ∼30%). An increment of the errors with cloudiness was also observed. For CS with mean GHI (global horizontal irradiance) ∼ 650 W/m"2 the errors are 8%, for SC 20% and for BC and OC the errors were greater (>40%) but correspond to much lower radiation levels (<120 W/m"2) of consequently lower energy potential impact. The total energy potential for each ground station ranges from 1.5 to 1.9 MWh/m"2, while the mean monthly forecast error was found to be consistently below 10%. - Highlights: • Long term measurements at different atmospheric cases are needed for energy forecasting model evaluations. • The total energy potential at the Greek sites presented ranges from 1.5 to 1.9 MWh/m"2. • Mean monthly energy forecast errors are within 10% for all cases analyzed. • Cloud presence results of an additional forecast error that varies with the cloud cover.

  5. A Practice-Oriented Bifurcation Analysis for Pulse Energy Converters. Part 2: An Operating Regime

    Kolokolov, Yury; Monovskaya, Anna

    The paper continues the discussion on bifurcation analysis for applications in practice-oriented solutions for pulse energy conversion systems (PEC-systems). Since a PEC-system represents a nonlinear object with a variable structure, then the description of its dynamics evolution involves bifurcation analysis conceptions. This means the necessity to resolve the conflict-of-units between the notions used to describe natural evolution (i.e. evolution of the operating process towards nonoperating processes and vice versa) and the notions used to describe a desirable artificial regime (i.e. an operating regime). We consider cause-effect relations in the following sequence: nonlinear dynamics-output signal-operating characteristics, where these characteristics include stability and performance. Then regularities of nonlinear dynamics should be translated into regularities of the output signal dynamics, and, after, into an evolutional picture of each operating characteristic. In order to make the translation without losses, we first take into account heterogeneous properties within the structures of the operating process in the parametrical (P-) and phase (X-) spaces, and analyze regularities of the operating stability and performance on the common basis by use of the modified bifurcation diagrams built in joint PX-space. Then, the correspondence between causes (degradation of the operating process stability) and effects (changes of the operating characteristics) is decomposed into three groups of abnormalities: conditionally unavoidable abnormalities (CU-abnormalities); conditionally probable abnormalities (CP-abnormalities); conditionally regular abnormalities (CR-abnormalities). Within each of these groups the evolutional homogeneity is retained. After, the resultant evolution of each operating characteristic is naturally aggregated through the superposition of cause-effect relations in accordance with each of the abnormalities. We demonstrate that the practice

  6. Teager-Kaiser Energy and Higher-Order Operators in White-Light Interference Microscopy for Surface Shape Measurement

    Abdel-Ouahab Boudraa

    2005-10-01

    Full Text Available In white-light interference microscopy, measurement of surface shape generally requires peak extraction of the fringe function envelope. In this paper the Teager-Kaiser energy and higher-order energy operators are proposed for efficient extraction of the fringe envelope. These energy operators are compared in terms of precision, robustness to noise, and subsampling. Flexible energy operators, depending on order and lag parameters, can be obtained. Results show that smoothing and interpolation of envelope approximation using spline model performs better than Gaussian-based approach.

  7. Energy, environmental and operation aspects of a SRF-fired fluidized bed waste-to-energy plant.

    De Gisi, Sabino; Chiarelli, Agnese; Tagliente, Luca; Notarnicola, Michele

    2018-03-01

    A methodology based on the ISO 14031:2013 guideline has been developed and applied to a full-scale fluidized bed waste to energy plant (WtE) burning solid recovered fuel (SRF). With reference to 3years of operation, the data on energy and environmental performance, on raw materials consumptions such as sand and diesel fuel, accidental reasons of plant shutdown, have been acquired and analyzed. The obtained results have allowed to quantify the energy and environmental performance of the WtE plant under investigation by varying the amount and mixings of the inlet waste, available in form of thickened and fluff (similar to coriander) SRF. In terms of the energy performance, the fluidized bed technology applied to the SRF was able to guarantee an adequate production of electricity (satisfying the market demands), showing a relative flexibility with respect to the inlet waste. In terms of net energy production efficiency, the plant showed values in the range of 13.8-14.9% in line with similar installations. In terms of the environmental performance, the adoption of a cleaning system based on SNCR (Selective Non Catalitic Reduction)+semi-dry scrubbing+Fabric filter generated emissions usually well below the limits set by the EU Directive 2000/76/EC as well as the Italian Law 46/2014 (more restrictive) with reference to all the key parameters. In terms of the plant shutdown, the majority of problems focused on the combustion chamber and boiler due to the erosion of the refractory material of the furnace as well as to the breaking of the superheaters of the boiler. In contrast, the mechanical and electrical causes, along with those related to the control and instrumentation system, were of secondary importance. The sand bed de-fluidization was also among the leading causes of a frequent plant shutdown. In particular, results showed how although the SRF presents standard characteristics, the use of different mixtures may affect the number of plant shutdowns. The full

  8. Experience relevant to safety obtained from reactor decommissioning operations in the French Atomic Energy Commission

    Giraudel, B.; Langlois, G.

    1979-01-01

    From among the nuclear facilities constructed in France the authors cite eight large reactors, ranging from critical assemblies to power reactors, that have been finally shut-down since 1965. A brief account is given of the way in which the various operations were carried out after the final control rod drop, a distinction being drawn between the shut-down proper and the containment and dismantling work. A description is also given, from the technical and regulatory standpoint, of the final stage attained, and mention is made of French safety arrangements and of the part played by the safety services during decommissioning operations. Among the lessons derived from French experience, the authors mention the completion of operations without any serious safety problems, and with guarantees for the protection of personnel and the population as a whole, by conventional techniques; the advantage of planning decommissioning operations from the very beginning of construction of the facilities; and the importance of filing descriptive documents. In view of the experience gained, the French Atomic Energy Commission has devised internal procedures for facilitating the application of regulations governing the shut-down and decommissioning phases, which are aimed at preserving surveillance procedures similar to those in force during normal operation. (author)

  9. Implementing energy efficiency: Challenges and opportunities for rural electric co-operatives and small municipal utilities

    Wilson, Elizabeth J.; Plummer, Joseph; Fischlein, Miriam; Smith, Timothy M.

    2008-01-01

    Challenges in implementing demand side management (DSM) programs in rural electric co-operatives and small municipal utilities are not well understood, yet these organizations sell roughly 15% of electricity in the US, many are more coal-intensive than investor-owned utilities (IOUs), and they are politically important-rural electric co-operatives cover about 75% of the US land area and municipal utilities are found in every state except Hawaii. We provide a background on rural co-operatives and municipal utilities in the context of the US electric sector and highlight the challenges and opportunities of implementing DSM programs in these institutions. Where past studies of utility DSM have mostly focused on IOUs or consisted of qualitative case studies of municipal utilities with exemplary DSM performance, this study makes a unique contribution to the DSM literature by systematically analyzing an entire co-operative and municipal utility population in Minnesota through the use of a survey. In doing so, we provide policy recommendations relevant to energy planners and policy makers to support DSM in rural electric co-operatives and municipal utilities

  10. Operating cycle optimization for a Magnus effect-based airborne wind energy system

    Milutinović, Milan; Čorić, Mirko; Deur, Joško

    2015-01-01

    Highlights: • Operating cycle of a Magnus effect-based AWE system has been optimized. • The cycle trajectory should be vertical and far from the ground based generator. • Vertical trajectory provides high pulling force that drives the generator. • Large distance from the generator is required for the feasibility of the cycle. - Abstract: The paper presents a control variables optimization study for an airborne wind energy production system. The system comprises an airborne module in the form of a buoyant, rotating cylinder, whose rotation in a wind stream induces the Magnus effect-based aerodynamic lift. Through a tether, the airborne module first drives the generator fixed on the ground, and then the generator becomes a motor that lowers the airborne module. The optimization is aimed at maximizing the average power produced at the generator during a continuously repeatable operating cycle. The control variables are the generator-side rope force and the cylinder rotation speed. The optimization is based on a multi-phase problem formulation, where operation is divided into ascending and descending phases, with free boundary conditions and free cycle duration. The presented simulation results show that significant power increase can be achieved by using the obtained optimal operating cycle instead of the initial, empirically based operation control strategy. A brief analysis is also given to provide a physical interpretation of the optimal cycle results

  11. Morteros acumuladores con parafinas microencapsuladas para el aprovechamiento de la energía solar en suelos radiantes

    Zetola Vargas, Vicente Andrés

    2013-01-01

    Esta Tesis plantea la pregunta de si el uso de morteros con parafinas microencapsuladas combinado con colectores solares térmicos puede reducir el consumo de energías convencionales, en un sistema tradicional de suelo radiante. Se pretende contribuir al conocimiento acerca del efecto que produce en el edificio, el calor latente acumulado en suelos radiantes, utilizando morteros de cemento Portland con material de cambio de fase (PCM), en conjunto con la energía solar. Para cumplir con este pr...

  12. Control characteristics and heating performance analysis of automatic thermostatic valves for radiant slab heating system in residential apartments

    Ahn, Byung-Cheon [Department of Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea); Song, Jae-Yeob [Graduate School, Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea)

    2010-04-15

    Computer simulations and experiments are carried out to research the control characteristics and heating performances for a radiant slab heating system with automatic thermostatic valves in residential apartments. An electrical equivalent R-C circuit is applied to analyze the unsteady heat transfer in the house. In addition, the radiant heat transfer between slabs, ceilings and walls in the room is evaluated by enclosure analysis method. Results of heating performance and control characteristics were determined from control methods such as automatic thermostatic valves, room air temperature-sensing method, water-temperature-sensing method, proportional control method, and On-Off control method. (author)

  13. Optimization of operating conditions of distillation columns: an energy saving option in refinery industry

    Alireza Fazlali

    2010-01-01

    Full Text Available While energy prices continue to climb, it conservation remains the prime concern for process industries. The daily growth of energy consumption throughout the world and the real necessity of providing it, shows that optimization of energy generation and consumption units is an economical and sometimes vital case. Hence, the optimization of a petroleum refinery is aimed towards great production and an increase in quality. In this research, the atmospheric distillation unit of the Iran-Arak-Shazand petroleum refinery was subject to optimization efforts. It was performed by the means of using a simulator with the aim to earn more overhead products. In the next step the optimization results from the simulators were carried out in the real world, at the above mentioned unit. Results demonstrate that the changes in the real operating conditions increase the overhead products with desirable quality. Finally, a net economical balance between the increments of the overhead products and the energy consumption shows an energy saving in this refinery.

  14. Effect of operating conditions on energy efficiency for a small passive direct methanol fuel cell

    Chu Deryn; Jiang Rongzhong

    2006-01-01

    Energy conversion efficiency was studied in a direct methanol fuel cell (DMFC) with an air-breathing cathode using Nafion 117 as electrolyte membrane. The effect of operating conditions, such as methanol concentration, discharge voltage and temperature, on Faradic and energy conversion efficiencies was analyzed under constant voltage discharge with quantitative amount of fuel. Both of Faradic and energy conversion efficiencies decrease significantly with increasing methanol concentration and environmental temperature. The Faradic conversion efficiency can be as high as 94.8%, and the energy conversion efficiency can be as high as 23.9% if the environmental temperature is low enough (10 deg. C) under constant voltage discharge at 0.6 V with 3 M methanol for a DMFC bi-cell. Although higher temperature and higher methanol concentration can achieve higher discharge power, it will result in considerable losses of Faradic and energy conversion efficiencies for using Nafion electrolyte membrane. Development of alternative highly conductive membranes with significantly lower methanol crossover is necessary to avoid loss of Faradic conversion efficiency with temperature and with fuel concentration

  15. China Building Energy Consumption: Definitions and Measures from an Operational Perspective

    Wei Wei

    2017-04-01

    Full Text Available China building energy consumption (BEC has been gradually derived and also sparked attention. However, something worth discussing is estimating the BEC based on the definition of life cycle or building operation. In addition, there exists discrepancy in the previous studies and the real status of BEC has not been known well. In order to settle the disputes over the calculation of BEC, this paper establishes an appropriate accounting method of building energy to present the BEC situation in China and lays the foundation for policymakers to develop appropriate energy saving policies. Meanwhile, this study attempts to clarify the BEC to help policymakers assess the effect of environmental policies. Using the method in this document, we find that the energy consumption of buildings just accounts for 15%–16% of the final total energy consumption in China; by contrast, the previous studies usually have double accounting through a top-down approach if central heat supply of buildings was taken into additional consideration.

  16. ANALYSIS OF ENERGY EFFICIENCY OF OPERATING MODES OF ELECTRICAL SYSTEMS WITH THE TRACTION LOADS

    V. E. Bondarenko

    2017-03-01

    Full Text Available Innovative scenarios of reliable energy supply of transportation process aimed at reducing the specific energy consumption and increase energy efficiency of the systems of electric traction. The paper suggests innovative energy saving directions in traction networks of railways and new circuit solutions accessing traction substations in energy systems networks, ensure energy security of the transportation process. To ensure the energy security of rail transport special schemes were developed to propose the concept of external power traction substations, which would increase the number of connections to the networks of 220 – 330 kV, as well as the creation of transport and energy corridors, development of its own supply of electric networks of 110 kV substations and mobile RP-110 kV of next generation. Therefore, the investment program of the structures owned by the Ukrainian Railways (Ukrzaliznytsia need to be synchronized in their technological characteristics, as well as the criteria of reliability and quality of power supply with the same external energy investment programs. It is found that without any load on left or right supplying arm one of two less loaded phases of traction transformer begins generating specific modes in the supplying three-phase line. Thus, modes of mobile substation cause leakage in one of the phases of the supply line of traction transformers of active-capacitive current, and as a result generating energy in the main power line of 154 kV, which is fixed and calculated by electricity meters. For these three phase mode supply network is necessary to use 1st algorithm, i.e. taking into account the amount of electricity as the energy in all phases. For effective application of reactive power compensation devices in the AC traction power supply systems it is proposed to develop regulatory documentation on necessity of application and the order of choice of parameters and placement of compensation systems taking into

  17. EnergySolution's Clive Disposal Facility Operational Research Model - 13475

    Nissley, Paul; Berry, Joanne [EnergySolutions, 2345 Stevens Dr. Richland, WA 99354 (United States)

    2013-07-01

    EnergySolutions owns and operates a licensed, commercial low-level radioactive waste disposal facility located in Clive, Utah. The Clive site receives low-level radioactive waste from various locations within the United States via bulk truck, containerised truck, enclosed truck, bulk rail-cars, rail boxcars, and rail inter-modals. Waste packages are unloaded, characterized, processed, and disposed of at the Clive site. Examples of low-level radioactive waste arriving at Clive include, but are not limited to, contaminated soil/debris, spent nuclear power plant components, and medical waste. Generators of low-level radioactive waste typically include nuclear power plants, hospitals, national laboratories, and various United States government operated waste sites. Over the past few years, poor economic conditions have significantly reduced the number of shipments to Clive. With less revenue coming in from processing shipments, Clive needed to keep its expenses down if it was going to maintain past levels of profitability. The Operational Research group of EnergySolutions were asked to develop a simulation model to help identify any improvement opportunities that would increase overall operating efficiency and reduce costs at the Clive Facility. The Clive operations research model simulates the receipt, movement, and processing requirements of shipments arriving at the facility. The model includes shipment schedules, processing times of various waste types, labor requirements, shift schedules, and site equipment availability. The Clive operations research model has been developed using the WITNESS{sup TM} process simulation software, which is developed by the Lanner Group. The major goals of this project were to: - identify processing bottlenecks that could reduce the turnaround time from shipment arrival to disposal; - evaluate the use (or idle time) of labor and equipment; - project future operational requirements under different forecasted scenarios. By identifying

  18. Standardization of the energy performance of photovoltaic modules in real operating conditions

    Viganó Davide

    2014-01-01

    Full Text Available The performance of a PV module at STC [1] is a useful indicator for comparing the peak performance of different module types, but on its own is not sufficient to accurately predict how much energy a module will deliver in the field when subjected to a wide range of real operating conditions [2]. An Energy Rating approach has to be preferred for that aim. It is currently under development the standard series IEC 61853 on Energy Rating, for which only part 1 [3] has been issued. It describes methods to characterize the module performance as a function of irradiance and temperature. The reproducibility of the power matrix measurements obtained by the three different methods specified in the standard, namely: under natural sunlight using a tracking system; under natural sunlight without tracker; and a large area pulsed solar simulator of Class AAA were evaluated and discussed [4,5]. The work here presented is focused on the second method listed above, which explores the real working conditions for a PV device and therefore it represents the situation where Energy Rating procedures are expected to give the largest deviations from the STC predictions. The system for continuous monitoring of module performances, already implemented at ESTI, has been recently replaced with a new system having a number of improvements described in the following. The two system results have been compared showing a discrete compatibility. The two power matrices are then merged together using a weighted average and compared to those acquired with the other two remaining “ideal” systems. An interesting tendency seems to come up from this comparison, making the power rating under real operating conditions an essential procedure for energy rating purposes.

  19. Micro combined heat and power operating on renewable energy for residential building

    Aoun, Bernard

    2008-01-01

    The building sector consumes more than 43% of the total national energy consumption in France leading to more than 25% of CO 2 emissions associated to this energy consumption. A large number of options exist to limit CO 2 emissions and to improve the performance of buildings. One of these options is developed in this thesis, the use of renewable energies (solar and biomass) in combined production of heat and power. Conventional systems of combined heat and power production are briefly analyzed. The major part of this work has been focused on the development of a micro-CHP system based on an organic Rankine cycle operating on renewable energies intermittent and non-intermittent (solar and wood). The working fluids have been analyzed to allow reaching high thermodynamic performance. The different promising technologies, for each components of the system are identified, depending on the working fluid. A special test bench has been designed and realized to test and characterize an oil-free vapor scroll expander suitable for our application. The different components have been sized using computerized tools developed for the modeling of the Organic Rankine cycle. A dynamic simulation tool has been developed to simulate the annual performance of the micro-CHP system operating under different climate conditions and thermal loads. Results show that the micro-CHP system could save more than 40% of the primary energy consumption and up to 60% of CO 2 emissions. The Levelized electricity cost has been calculated using economic analysis; results show that the electricity cost (50 c-euros/kWhel) is still high compared to other technologies. (author)

  20. Operational design and pressure response of large-scale compressed air energy storage in porous formations

    Wang, Bo; Bauer, Sebastian

    2017-04-01

    With the rapid growth of energy production from intermittent renewable sources like wind and solar power plants, large-scale energy storage options are required to compensate for fluctuating power generation on different time scales. Compressed air energy storage (CAES) in porous formations is seen as a promising option for balancing short-term diurnal fluctuations. CAES is a power-to-power energy storage, which converts electricity to mechanical energy, i.e. highly pressurized air, and stores it in the subsurface. This study aims at designing the storage setup and quantifying the pressure response of a large-scale CAES operation in a porous sandstone formation, thus assessing the feasibility of this storage option. For this, numerical modelling of a synthetic site and a synthetic operational cycle is applied. A hypothetic CAES scenario using a typical anticline structure in northern Germany was investigated. The top of the storage formation is at 700 m depth and the thickness is 20 m. The porosity and permeability were assumed to have a homogenous distribution with a value of 0.35 and 500 mD, respectively. According to the specifications of the Huntorf CAES power plant, a gas turbine producing 321 MW power with a minimum inlet pressure of 43 bars at an air mass flowrate of 417 kg/s was assumed. Pressure loss in the gas wells was accounted for using an analytical solution, which defines a minimum bottom hole pressure of 47 bars. Two daily extraction cycles of 6 hours each were set to the early morning and the late afternoon in order to bypass the massive solar energy production around noon. A two-year initial filling of the reservoir with air and ten years of daily cyclic operation were numerically simulated using the Eclipse E300 reservoir simulator. The simulation results show that using 12 wells the storage formation with a permeability of 500 mD can support the required 6-hour continuous power output of 321MW, which corresponds an energy output of 3852 MWh per