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Reinforcement Learning Model for Energy System Management to Ensure Energy Efficiency and Comfort in Buildings
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作者 Inna Bilous Dmytro Biriukov +3 位作者 Dmytro Karpenko Tatiana Eutukhova Oleksandr Novoseltsev Volodymyr Voloshchuk 《Energy Engineering》 EI 2024年第12期3617-3634,共18页
This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within buildings.Enhancing the comfort o... This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within buildings.Enhancing the comfort of living or working in buildings often necessitates increased consumption of energy and material,such as for thermal upgrades,which consequently incurs additional economic costs.It is crucial to acknowledge that such improvements do not always lead to a decrease in total pollutant emissions,considering emissions across all stages of production and usage of energy and materials aimed at boosting energy efficiency and comfort in buildings.In addition,it explores the methods and mechanisms for modeling the operating modes of electric boilers used to collectively improve energy efficiency and indoor climatic conditions.Using the developed mathematical models,the study examines the dynamic states of building energy supply systems and provides recommendations for improving their efficiency.These dynamic models are executed in software environments such as MATLAB/Simscape and Python,where the component detailing schemes for various types of controllers are demonstrated.Additionally,controllers based on reinforcement learning(RL)displayed more adaptive load level management.These RL-based controllers can lower instantaneous power usage by up to 35%,reduce absolute deviations from a comfortable temperature nearly by half,and cut down energy consumption by approximately 1%while maintaining comfort.When the energy source produces a constant energy amount,the RL-based heat controllermore effectively maintains the temperature within the set range,preventing overheating.In conclusion,the introduced energydynamic building model and its software implementation offer a versatile tool for researchers,enabling the simulation of various energy supply systems to achieve optimal energy efficiency and indoor climate control in buildings. 展开更多
关键词 Building energy management building heating system dynamic modeling reinforcement learning energy efficiency comfortable temperature
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Thoughts on Energy Solutions to Alleviation of Air Pollution during the Heating Period in Key Areas
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作者 Zhao Wei Hu Zhengxin Wang Sheng 《Meteorological and Environmental Research》 CAS 2019年第4期7-10,共4页
Since the implementation of the Action Plan for Air Pollution Prevention and Control , all regions of China have steadily promoted the prevention and control of air pollution and achieved results continuously. However... Since the implementation of the Action Plan for Air Pollution Prevention and Control , all regions of China have steadily promoted the prevention and control of air pollution and achieved results continuously. However, the atmospheric environment in key areas such as Beijing-Tianjin-Hebei region, the Yangtze River Delta region, and Fenwei Plain is still severe, and especially during the heating period heavy pollution occurs frequently, which has become the focus and difficulty of improving the quality of the atmospheric environment and is also the weakest link of China s air pollution control at present. How to alleviate air pollution, how to win the battle of pollution prevention and control, how to hold the fruits of the blue sky defense war, energy consumption is key. 展开更多
关键词 Alleviation KEY areas KEY CITIES heating period Prevention and control of air pollution Blue SKY defense energy solution
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Experimental study and energy saving analysis of a novel radiant ceiling heating system 被引量:1
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作者 汪峰 梁彩华 张小松 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期118-123,共6页
In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experi... In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experiments. In addition, the energy saving potential of the novel heating system is discussed in terms of the COP (coefficient of performance) of the ground source heat pump and the exergy efficiency of the radiant terminal. The results indicate that the heating system shows high thermal stability and thermal comfort. When the system reaches a stable condition, the radiant heat transfer accounts for 62.7% of the total heat transfer, and the total heat transfer can meet the heating demands of most buildings. Compared to a radiant floor heating system, it offers advantages in a shorter preheating time, a lower supply water temperature and a stronger heating capability. The COP of the ground source heat pump is increased greatly when the supply water temperature is 28 to 33 ℃, and the exergy efficiency of the metal ceiling with capillary tubes is 1.6 times that of the radiant floor when the reference temperature is 5 ℃ The novel radiant ceiling heating system shows a tremendous energy saving potential. 展开更多
关键词 radiant heating system capillary tube heatingperformance energy saving exergy efficiency
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Energy Efficient Air Conditioning System Using Geothermal Cooling-Solar Heating in Gujarat, India 被引量:1
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作者 Sneha Shahare T. Harinarayana 《Journal of Power and Energy Engineering》 2016年第1期57-71,共15页
It is well known that one unit of electrical energy saved is equal to more than two units produced. One way of economizing the power is utilization of energy efficient systems at all locations. In the present study, t... It is well known that one unit of electrical energy saved is equal to more than two units produced. One way of economizing the power is utilization of energy efficient systems at all locations. In the present study, the air conditioning system is analysed and an innovative way is suggested. We use natural low temperature of shallow sub surface (1 - 3 m) of the earth—geothermal cooling system. It is known that majority of the households and the apartment complexes in India have two tanks for water storage. One is the underground water sump and the other is the overhead water tank. In our study, we use these two water storage systems for space cooling during summer and also for heating during winter. The main aim of our paper is air-conditioning of the space in an economic way to save electricity. It is based on a simple idea of transferring the low temperature from underground water sump to the room in the house using water as a mode of transport. Since India is a tropical country located at low latitude, most of the year, the air temperature is high and demands space cooling. However, for a couple of months during severe winter months (Dec.-Jan.) at Ahmedabad, heating of the space is required. For heating the space, we suggest to use the well-known solar water heater. Effective use of heat exchanger is shown through computation, modelling schemes and lab experiment. We recommend geothermal cooling for 10 months in a year and solar hot water system during 2 months of winter. It is observed that the ambient air temperature of 35°C - 40°C in the room can be brought down to 26°C without much consumption of electricity. In a similar manner, the room temperature at night (13°C) during winter in Ahmedabad can be increased to 27°C through circulation of water from solar water heater in the heat exchanger. 展开更多
关键词 energy efficiency Geothermal Cooling Air Conditioning CFD Thermal Comfort Earth Water Heat Exchanger
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EFFICIENT HEATING AND COOLING SYSTEMS FOR LOW-ENERGY HOUSES
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作者 Vasile Minea 《Journal of Green Building》 2012年第4期16-35,共20页
Buildings account for a large amount of land use, energy and water consumption, and atmospheric pollution. For example, in the United States, they use 40% of the total national energy consumption (56% by residential d... Buildings account for a large amount of land use, energy and water consumption, and atmospheric pollution. For example, in the United States, they use 40% of the total national energy consumption (56% by residential dwellings), produce 38% of the total carbon dioxide emissions, and account for 12.2% of the total quantity of water consumed (2006). In this context, buildings with considerably reduced energy consumption are a key strategy to achieving energy savings and climate protection targets in both the residential and commercial/institutional sectors [1]. This article reviews a number of heating and cooling systems-existing and/or under development- available for residential buildings and briefly outlines some research projects and initiatives, as well as technical achievements in Canada and other developed countries over the last few years. 展开更多
关键词 low-energy house building integrated photovoltaic thermal system energy efficiency heat pump heat recovery
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Initiative Optimization Operation Strategy and Multi-objective Energy Management Method for Combined Cooling Heating and Power 被引量:4
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作者 Feng Zhao Chenghui Zhang Bo Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第4期385-393,共9页
This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power U+0028 CCHP U+0029 with storage systems. Initially, the initiative ... This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power U+0028 CCHP U+0029 with storage systems. Initially, the initiative optimization operation strategy of CCHP system in the cooling season, the heating season and the transition season was formulated. The energy management of CCHP system was optimized by the multi-objective optimization model with maximum daily energy efficiency, minimum daily carbon emissions and minimum daily operation cost based on the proposed initiative optimization operation strategy. Furthermore, the pareto optimal solution set was solved by using the niche particle swarm multi-objective optimization algorithm. Ultimately, the most satisfactory energy management scheme was obtained by using the technique for order preference by similarity to ideal solution U+0028 TOPSIS U+0029 method. A case study of CCHP system used in a hospital in the north of China validated the effectiveness of this method. The results showed that the satisfactory energy management scheme of CCHP system was obtained based on this initiative optimization operation strategy and multi-objective energy management method. The CCHP system has achieved better energy efficiency, environmental protection and economic benefits. © 2014 Chinese Association of Automation. 展开更多
关键词 CARBON COOLING Cooling systems energy efficiency energy management heating Multiobjective optimization OPTIMIZATION Pareto principle
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Country-level meteorological parameters for building energy efficiency in China 被引量:3
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作者 LIU Yan WANG Shang-yu +2 位作者 CAO Qi-meng LU Mei YANG Liu 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第7期2301-2316,共16页
Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal eng... Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal engineering design,heating ventilation and air conditioning design,and energy consumption simulations.Focusing on the key issues such as low spatial coverage and the lack of daily or higher time resolution data,daily and hourly models of the surface meteorological data and solar radiation were established and evaluated.Surface meteorological data and solar radiation data were generated for 1019 cities and towns in China from 1988 to 2017.The data were carefully compared,and the accuracy was proved to be high.All the meteorological parameters can be assessed in the building sector via a sharing platform.Then,country-level meteorological parameters were developed for energy-efficient building assessment in China,based on actual meteorological data in the present study.This set of meteorological parameters may facilitate engineering applications as well as allowing the updating and expansion of relevant building energy efficiency standards.The study was supported by the National Science and Technology Major Project of China during the 13th Five-Year Plan Period,named Fundamental parameters on building energy efficiency in China,comprising of 15 top-ranking universities and institutions in China. 展开更多
关键词 building energy efficiency building thermal engineering heating ventilation and air conditioning meteorological parameters solar radiation
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An innovative trigeneration system using biogas as renewable energy 被引量:1
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作者 Grazia Leonzio 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1179-1191,共13页
One of the ways to decrease the global primary energy consumption and the corresponding greenhouse gas emissions is the application of the combined cooling, heating and power generation technologies, known as trigener... One of the ways to decrease the global primary energy consumption and the corresponding greenhouse gas emissions is the application of the combined cooling, heating and power generation technologies, known as trigeneration system. In this research an innovative trigeneration system, composed by an absorption heat pump, a mechanical compression heat pump, a steam plant, and a heat recovery plant is developed. The low tem- perature heat produced by absorption chiller is sent to a mechanical compression heat pump, that receives pro- cess water at low temperature from the heat recovery plant and bring it to higher temperatures. The trigeneration system is fed by biogas, a renewable energy. A design and a simulation of the system are developed by ChemCad 6.3 software. The plant produces 925 kW of electrical energy, 2523 kW of thermal energy and 473 kW of cooling energy, by the combustion of 3280 kW of biogas. Primary energy rate (P.E.R.) is equal 1.04 and a sensitivity analysis is carried out to evaluate the effect of cooling capacity, produced electrical energy and process water temperature. The first has a negative effect, while other parameters have a positive effect on P.E.R. Compared to a cogeneration system, the tdgeneration plant produces the 28% higher of power and the 40% lower of carbon dioxide emissions. An economic analysis shows that the plant is economically feasible only consid- ering economic incentives obtained by the use of heat pumps and steam plant at high efficiency. Saving 6431 t.a-1 corresponding to 658000 EUR.a-1 of incentives, the plant has a net present value (N.P.V.) and a pay back period (P.B.P.) respectively equal to 371000 EUR and 4 year. Future works should optimize the process considering cost and energetic efficiency as the two objective functions. 展开更多
关键词 Trigeneration system BIOGAS energy efficiency Process simulation Heat pumps Environmental analysis
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Energy Efficiency in Building: Case of Buildings at the University of Ibadan, Nigeria 被引量:1
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作者 K. M. Odunfa T. O. Ojo +1 位作者 V. O. Odunfa O. S. Ohunakin 《Journal of Building Construction and Planning Research》 2015年第1期18-26,共9页
Nigeria today faces serious challenge in providing adequate energy to meet the needs of her citizenry. Efforts are currently geared towards generation of more energy to ease the problem. While these efforts are commen... Nigeria today faces serious challenge in providing adequate energy to meet the needs of her citizenry. Efforts are currently geared towards generation of more energy to ease the problem. While these efforts are commendable, it is equally desirable to explore ways to minimize consumption of generated energy. The objective of this work is to investigate the effect of building orientation on energy demand in buildings. This paper considered the use of standard design considerations, fundamental cooling load equations and the guidelines stipulated by the American Society of Heating, Cooling and Air conditioning Engineers (ASHRAE). The study takes the designs of three buildings within the University of Ibadan, Nigeria into consideration with the view to harness the energy saving potentials through building orientation and selection of efficient cooling equipment. The results obtained were 155.34, 224.75, 86.35 kW and 163.60, 232.04 and 90.64 kW for the three lecture envelopes including the Faculty of Science, CBN and the Department of Chemistry lecture theatres using the North-South and East-West building orientations respectively. Increase in energy demand of 7.96, 7.29 and 4.29 kW was thus obtained with the East-West building orientation over North-South. Energy efficiency is thus guaranteed with North-South building orientation. 展开更多
关键词 energy efficiency ORIENTATION COOLING Load heating Ventilation and AIR-CONDITIONING
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Energy-Efficient Optimal Guaranteed Cost Intermittent-Switch Control of a Direct Expansion Air Conditioning System 被引量:1
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作者 Jun Mei Zhenyu Lu +1 位作者 Junhao Hu Yuling Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第11期1852-1866,共15页
To improve the energy efficiency of a direct expansion air conditioning(DX A/C) system while guaranteeing occupancy comfort, a hierarchical controller for a DX A/C system with uncertain parameters is proposed. The con... To improve the energy efficiency of a direct expansion air conditioning(DX A/C) system while guaranteeing occupancy comfort, a hierarchical controller for a DX A/C system with uncertain parameters is proposed. The control strategy consists of an open loop optimization controller and a closed-loop guaranteed cost periodically intermittent-switch controller(GCPISC). The error dynamics system of the closed-loop control is modelled based on the GCPISC principle. The difference,compared to the previous DX A/C system control methods, is that the controller designed in this paper performs control at discrete times. For the ease of designing the controller, a series of matrix inequalities are derived to be the sufficient conditions of the lower-layer closed-loop GCPISC controller. In this way, the DX A/C system output is derived to follow the optimal references obtained through the upper-layer open loop controller in exponential time, and the energy efficiency of the system is improved. Moreover, a static optimization problem is addressed for obtaining an optimal GCPISC law to ensure a minimum upper bound on the DX A/C system performance considering energy efficiency and output tracking error. The advantages of the designed hierarchical controller for a DX A/C system with uncertain parameters are demonstrated through some simulation results. 展开更多
关键词 energy efficiency hierarchical control open loop optimal control optimal guaranteed cost periodically intermittent-switch control
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A New Type of Paper-frame Cavernous Material and Its Application in Energy Efficiency in Buildings
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作者 袁海庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第4期80-82,共3页
This paper introduces a new type of paper-frame cavernous material, which is a made-up hollow material, by using silicate-cinder size to drench and daub. It possesses excellent performances such as light-weight, high-... This paper introduces a new type of paper-frame cavernous material, which is a made-up hollow material, by using silicate-cinder size to drench and daub. It possesses excellent performances such as light-weight, high-intensity, fire-resistance, sound-insulation, heat-insulation and no-pollution. Composed with concrete materials, a new type of bearing and energy-efficient block can be gained, which is kind of excellent wall materials and has a wide application prospect. 展开更多
关键词 energy efficiency in buildings wall material heat transfer coefficient coefficient of thermal conductivity heat resistance paper-frame cavernous material
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Economic feasibility and efficiency enhancement approaches for in situ upgrading of low-maturity organic-rich shale from an energy consumption ratio perspective
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作者 LU Shuangfang WANG Jun +5 位作者 LI Wenbiao CAO Yixin CHEN Fangwen LI Jijun XUE Haitao WANG Min 《地学前缘》 EI CAS CSCD 北大核心 2023年第1期281-295,共15页
The technical feasibility of in situ upgrading technology to develop the enormous oil and gas resource potential in low-maturity shale is widely acknowledged.However,because of the large quantities of energy required ... The technical feasibility of in situ upgrading technology to develop the enormous oil and gas resource potential in low-maturity shale is widely acknowledged.However,because of the large quantities of energy required to heat shale,its economic feasibility is still a matter of debate and has yet to be convincingly demonstrated quantitatively.Based on the energy conservation law,the energy acquisition of oil and gas generation and the energy consumption of organic matter cracking,shale heat-absorption,and surrounding rock heat dissipation during in situ heating were evaluated in this study.The energy consumption ratios for different conditions were determined,and the factors that influence them were analyzed.The results show that the energy consumption ratio increases rapidly with increasing total organic carbon(TOC)content.For oil-prone shales,the TOC content corresponding to an energy consumption ratio of 3 is approximately 4.2%.This indicates that shale with a high TOC content can be expected to reduce the project cost through large-scale operation,making the energy consumption ratio after consideration of the project cost greater than 1.In situ heating and upgrading technology can achieve economic benefits.The main methods for improving the economic feasibility by analyzing factors that influence the energy consumption ratio include the following:(1)exploring technologies that efficiently heat shale but reduce the heat dissipation of surrounding rocks,(2)exploring technologies for efficient transformation of organic matter into oil and gas,i.e.,exploring technologies with catalytic effects,or the capability to reduce in situ heating time,and(3)establishing a horizontal well deployment technology that comprehensively considers the energy consumption ratio,time cost,and engineering cost. 展开更多
关键词 shale gas content in situ upgrading energy consumption ratio high-efficiency heating efficient organic matter transformation
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Evaluation of Energy Efficiency Performance of Heated Windows
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作者 Hari Swarup Jammulamadaka Bhaskaran Gopalakrishnan +3 位作者 Subodh Chaudhari Senthil Sundaramoorthy Akash Rajesh Mehta Roseline Mostafa 《Energy Engineering》 EI 2022年第1期1-16,共16页
Fenestration systems are widely used across the world.There is expansive research on window configurations,frames,and glazing technology,but not enough research has been published on reducing window heat loss through ... Fenestration systems are widely used across the world.There is expansive research on window configurations,frames,and glazing technology,but not enough research has been published on reducing window heat loss through heat application to a pane.The presented study attempted to evaluate the performance of heated windows by developing an experimental setup to test a window at various temperatures by varying the power input to thewindow.Heated double pane window was installed in an insulated box.Atemperature gradient was developed across the window by cooling one side of the window using gel-based ice packs.The other face of the window was heated by enabling power at different wattages through the window.The temperature of the inside and outside panes,current and voltage input,and temperature of the room and box were recorded.The data was used to calculate the apparent effective resistance of the window when not being heated vs.when being heated.The study concluded that,when window temperature was maintained close to the room temperature,the heated double pane window is effective in reducing heat loss by as much as 50%as compared to a non-heated double pane window.When temperature of the window was much higher than the room temperature,the heat loss through the window increased beyond that of a non-heated window.The issues encountered during the current stages of experiments are noted,and recommendations are provided for future studies. 展开更多
关键词 Heated windows perimeter heating window efficiency building energy models floor heating
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Energy Efficiency Classification for Agricultural Heater
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作者 Yonngiung Kim Geumchoon Kang Youngj in Kim Chungkil Kim Jiwon Seo 《Journal of Agricultural Science and Technology(A)》 2012年第10期1149-1154,共6页
Classification of energy efficiency system for agricultural heater was discussed and analyzed in order to derive an energy efficiency classification scheme for agricultural heater. Current practices of energy efficien... Classification of energy efficiency system for agricultural heater was discussed and analyzed in order to derive an energy efficiency classification scheme for agricultural heater. Current practices of energy efficiency programs for other products such as residential gas boiler were investigated and analyzed. Test items including energy efficiency and standby power for agricultural heater were analyzed. With the data of residential gas boiler, grade distribution of energy efficiency system was made and evaluated. An energy efficiency classification scheme for agricultural heater was proposed and applied to agricultural heaters, and the scheme was justified. Introducing a new energy efficiency classification system to the agricultural heater industry, it is expected that considerable amount of fossil fuels can be reduced by adopting energy efficiency classification system. 展开更多
关键词 energy efficiency agricultural heater heating capacity classifying.
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Clean Coal &High Carbon Efficiency Energy Engineering
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作者 Stefan Petters Kalvin Tse 《Journal of Power and Energy Engineering》 2015年第4期348-355,共8页
Today we live in a world of Hydrocarbon Energy Carriers, where Carbon is always used as a Carrier for Hydrogen 1) Biomass (CH1.44O0.66 or C6H12O6);2) Natural Gas [NG] (CH4);3) Water Gas [C+H2O];4) Gasoline (C6H12, C7H... Today we live in a world of Hydrocarbon Energy Carriers, where Carbon is always used as a Carrier for Hydrogen 1) Biomass (CH1.44O0.66 or C6H12O6);2) Natural Gas [NG] (CH4);3) Water Gas [C+H2O];4) Gasoline (C6H12, C7H18, C8H18, etc.);5) Kerosene (C17H36, C18H38, C19H40, C20H42, C21H44, C22H46, etc.) and;6) Crude Oil. The Carbon aggregates are all storable and have worthwhile, logistically manageable energy densities. But whenever recovering Energy from the Carbon molarities, CO2 gets emitted into the atmosphere, while separate use of Hydrogen Energy contents carried by the Carbon moieties would just generate water vapor. Hydrogen is also the most important intermediary in Refineries, hydrogenating lower grade Hydrocarbons into higher potencies, or for removing Sulfur by the formation of Hydrogen Sulfur, that can be dissociated after its segregation from the Hydrocarbon products. But most of the internal Hydrogen yields in Refineries today is used for onsite production of Ammonia as a basis for Energy fertilizers in high performance agriculture. Because Hydrogen is awkward to store and transport, most of it is currently used captive within large size centralized plants as a reactant for producing Hydrocarbon energy carriers, using the Carbon as a carrier for the Hydrogen moieties, to then be distributed over big enough areas for consumption of the such large scale plants’ volumes. With recently proven achievements of Hydrogen production from excess Wind & Solar Power by electrolysis, Hydrogen could become available in abundant quantities, to be distributed locally within the coverage area of the transmission grid such Wind & Solar installations are feeding into. In combination with Carbon as a reactant such abundant Hydrogen could also be synthesized into Hydrocarbon Energy Carriers and substitute fossil commodities. 展开更多
关键词 Atmospheric CARBON CARBON efficiency CARBON Metabolism CARBON Re-Use Chemical energy Content Controlled Microbial Composting energy Carriers Fossil Substitute Commodities INTERMEDIARIES heating Value Hybrid Power Plant Hydrocarbon Hydrogen Organic Waste VALORIZATION Photosynthesis Productivity REFINERIES
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Evaluation of Energy-Efficiency Standards for Room Air Conditioners in the US
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作者 Alex Lekov Victor Franco Steve Meyers 《Open Journal of Energy Efficiency》 2012年第2期9-20,共12页
This article describes an analysis of the energy and economic impacts of possible energy efficiency standards for room air conditioners on both U.S. consumers and the nation as a whole. We used two metrics to determin... This article describes an analysis of the energy and economic impacts of possible energy efficiency standards for room air conditioners on both U.S. consumers and the nation as a whole. We used two metrics to determine the effect of standards on a representative sample of U.S. consumers: life-cycle cost change and payback period. For the national impact analysis, we evaluated national energy savings attributable to each potential standard, the monetary value of the energy savings to consumers of room air conditioners, the increased total installed costs because of standards, and the net present value of the difference between the value of energy savings and increased total installed costs. Our analysis indicates that standards for room air conditioners at efficiency level 3, which is 17% more efficient than today’s typical unit in the case of room air conditioners less than 6000 Btu/h with louvers and 12% more efficient in the case of room air conditioners 8000 - 13,999 Btu/h with louvers, would save close to one quad of energy over 30 years and have a net present value of consumer benefit of between ?$0.14 billion and $1.82 billion, depending on the discount rate. In addition, such standards would reduce carbon dioxide emissions and NOx emissions. 展开更多
关键词 energy efficiency STANDARDS Room Air Conditioners Consumer Benefit energy SAVINGS LIFE-CYCLE Cost Payback period Emissions REDUCTIONS
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Polish District Heating Systems--Development Perspectives
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作者 Krzysztof Wojdyga 《Journal of Civil Engineering and Architecture》 2016年第3期268-279,共12页
The most economical and rational means of heat supply for city inhabitants are district heating systems. Heat generated in power plants and large heat sources is cheaper than heat from individual sources. The reason f... The most economical and rational means of heat supply for city inhabitants are district heating systems. Heat generated in power plants and large heat sources is cheaper than heat from individual sources. The reason for that is the amount of the generated heat and the used fuel (coal for most heat sources). District heating, a very important energy sub-sector for the Polish economy, provides heat supply to centralised heating systems, which, on average, satisfy 72% of the demand for heat in Polish cities. Therefore, several million Polish citizens use heat from district heating systems that produce heat in professional, industrial and municipal power plants. In Europe, over 100 million citizens use district heating systems. The present situation of the Polish district heating sector is a result of Poland's transformation that took place at the beginning of the 1990s. The reform put the obligation of heat supply on the local authorities, on the municipality, instead of the state. Along with the transformation, district heating also made huge technological and technical progress. Increasing expectations of recipients posed new challenges for the branch, however. 展开更多
关键词 District heating energy efficiency COGENERATION energy planning
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A Neuro-Fuzzy Based Adaptive Set-Point Heat Exchanger Control Scheme in District Heating System
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作者 Liang Huang Zaiyi Liao Zhao Lian 《Journal of Civil Engineering and Architecture》 2012年第11期1584-1588,共5页
The control of heat exchange stations in district heating system is critical for the overall energy efficiency and can be very difficult due to high level of complexity. A conventional method is to control the equipme... The control of heat exchange stations in district heating system is critical for the overall energy efficiency and can be very difficult due to high level of complexity. A conventional method is to control the equipment such that the temperature of hot water supply is maintained at a set-point that may be a fixed value or be compensated against the external temperature. This paper presents a novel scheme that can determine the optimal set-point of hot water supply that maximizes the energy efficiency whilst providing sufficient heating capacity to the load. This scheme is based on Adaptive Neuro-Fuzzy Inferential System. The aim of this study is to improve the overall performance of district heating systems. 展开更多
关键词 District heating system NEURO-FUZZY inferential sensor energy efficiency CONTROL
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Geothermal Energy Heating and Hot Water for a Detached House Project
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作者 Elena M. Femandez Rodriguez Eunice Villicaria Ortiz Jorge Xiberta Bernat 《材料科学与工程(中英文A版)》 2013年第7期499-504,共6页
关键词 地热能源 住宅项目 热水 供暖 立式 可再生能源 应用程序 安装设计
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Net energy of corn,soybean meal and rapeseed meal in growing pigs 被引量:11
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作者 Zhongchao Li Yakui Li +6 位作者 Zhiqian Lv Hu Liu Jinbiao Zhao Jean Noblet Fenglai Wang Changhua Lai Defa Li 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第4期875-884,共10页
Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to val... Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to validate the NE of these four ingredients using pig growth performance.Methods: In Exp.1, 24 barrows(initial BW = 36.4 ± 1.6 kg) were allotted to 1 of 4 diets which included a corn basal diet,a corn-soybean meal basal diet and two rapeseed meal diets containing 20% EP-RSM(9.5% ether extract) or SE-RSM(1.1% ether extract) substituted for corn and soybean meal. The design allowed the calculation of NE values of corn,soybean meal and rapeseed meals according to the difference method. In Exp.2, 175 growing pigs(initial BW = 36.0± 5.2 kg) were fed 1 of 5 diets for 28 d, with five pigs per pen and seven replications(pens) per treatment in order to validate the measured energy values. Diets were a corn-soybean meal diet and four diets including 10% or 20% EP-RSM and 10% or 20% SE-RSM.Results: The NE of corn, soybean meal, EP-RSM and SE-RSM were 12.46, 11.34, 11.71 and 8.83 MJ/kg DM, respectively. The NE to ME ratio of corn(78%) was similar to tabular values, however, the NE to ME ratios of soybean meal(70%) and rapeseed meal(76%) were greater than tabular values. The greater NE value in EP-RSM than in SE-RSM is consistent with its higher EE content. Increasing EP-RSM or SE-RSM did not affect the growth performance of pigs and the caloric efficiency of NE was comparable for al diets.Conclusions: The NE of EP-RSM was similar to soybean meal, and both were greater than SE-RSM. The DE, ME and NE values measured in Exp.1 are confirmed by results of Exp. 2 with comparable caloric efficiencies of DE, ME or NE for all diets. 展开更多
关键词 Caloric efficiency GROWING PIG Heat production NET energy RAPESEED MEAL
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