Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were i...Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were investigated by OCA30 automatic contact angle test instrument,metallography microscope and XRD instrument etc.Results suggests:adding alloy element to Cu may increase its surface free energy,and the more kinds of alloy elements are added,the more surface free energy increases;the alloy element Sn an increase the surface free energy of Cu-Zn alloy;Cu-Zn alloy with fir-tree crystal structure,great phase discrepancy and obvious composition aliquation has greater surface free energy;Cu-Zn alloy with compounds and serious surface crystal lattice distortion has greater surface free energy.展开更多
Many researches discussing reduced energy consumption for environmental protection focus on machine efficiency or process redesign. To optimize the machine operation time can also save the energy, and these researches...Many researches discussing reduced energy consumption for environmental protection focus on machine efficiency or process redesign. To optimize the machine operation time can also save the energy, and these researches have received great interests in recent years. This study considers three different states of machines, among processing there are two different speeds, to solve the problem of minimizing energy costs under time-of-use tariff with no tardy jobs in flexible flow shop. This problem is basically NP-hard, we proposed a hybrid genetic algorithm (GA) to solve problems in reasonable timeliness. The result shows that to optimize different states of machines under time-of use tariff can reduce energy costs significantly in on-time delivery.展开更多
It is researched that rural residential buildings in Heilongjieng consume high energy and the living environment is poor. The research aimed at designing low-carbon and energy-saving buildings in order to reduce energ...It is researched that rural residential buildings in Heilongjieng consume high energy and the living environment is poor. The research aimed at designing low-carbon and energy-saving buildings in order to reduce energy consumption by applying energy storage. Besides, the research used composite solar panel, waste- based inorganic foam materials, and polystyrene board as construction materials and integrated energy collection, living environment and farming by energy storage system. It is notable that the research would reduce pollution on environment caused by residential buildings, which coincides with national economy development and en- ergy strategy, promoting construction material industry development, with high social and economic benefits.展开更多
According to the high operating costs and a large number of energy waste in the current data center network architectures, we propose a kind of trusted flow preemption scheduling combining the energy-saving routing me...According to the high operating costs and a large number of energy waste in the current data center network architectures, we propose a kind of trusted flow preemption scheduling combining the energy-saving routing mechanism based on typical data center network architecture. The mechanism can make the network flow in its exclusive network link bandwidth and transmission path, which can improve the link utilization and the use of the network energy efficiency. Meanwhile, we apply trusted computing to guarantee the high security, high performance and high fault-tolerant routing forwarding service, which helps improving the average completion time of network flow.展开更多
A ceramic gas turbine can save energy because of its high thermal efficiency at high turbine inlet temperatures. This paper deals with the thermodynamic and economic aspects of a ceramic gas turbine cogeneration syste...A ceramic gas turbine can save energy because of its high thermal efficiency at high turbine inlet temperatures. This paper deals with the thermodynamic and economic aspects of a ceramic gas turbine cogeneration system. Here cogeneration means the simultaneous production of electrical en-ergy and useful thermal energy from the same facility. The thermodynamic performance of a ceramic gas turbine cycle is assessed using a computer model. This model is used in parametric studies of performance under partial loads and at various inlet air temperatures. The computed performance is compared to the measured performance of a conventional gas turbine cycle. Then, an economic evaluation of a ceramic gas turbine cogeneration system is investigated. Energy savings provided by this system are estimated on the basis of the distributions of heat/power ratios. The computed economic evaluation is compared to the actual economic performance of a conventional system in which boilers produce the required thermal energy and electricity is purchased from a utility.展开更多
The rapid development of China’s automobile industry has brought ever-increasing impact on resources,energy and environment,the energy-saving and new energy vehicles come into being accordingly.This article firstly s...The rapid development of China’s automobile industry has brought ever-increasing impact on resources,energy and environment,the energy-saving and new energy vehicles come into being accordingly.This article firstly systematically introduces the technical route of energy-saving and new energy vehicles of China,focusing on the key bottleneck problems arising from the construction process of current assessment system of the technical route for energy-saving and new energy vehicles,establishes the energy-saving and new energy vehicle business model assessment index system afterward based on the comparative analysis on energy-saving and new energy vehicle business assessment model and the full life cycle theory,and finally makes prospects and forecasts on vital problems of system boundary,dynamic optimization,simulation system of full life cycle assessment of energy-saving and new energy vehicle.展开更多
This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it ...This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.展开更多
The performance of a solar lighting and heating system(SLHS)based on the spectral splitting effect of nanofluids is presented in this paper.SLHS through nanofluids would split the sunlight spectrum into different wave...The performance of a solar lighting and heating system(SLHS)based on the spectral splitting effect of nanofluids is presented in this paper.SLHS through nanofluids would split the sunlight spectrum into different wavelength,and then introduce the visible light into the offices for lighting and absorb infrared energy to generate hot water.The Energy Plus software was used to analyze the energy consumption of typical office building located in the city of Harbin in China coupled with SLHS.Based on the simulation results two lighting zones were identified in the offices and the optimal lighting control strategy was developed for a full year.The performance models of SLHS with different light-receiving areas of 10 m^(2)and 40 m^(2)were simulated and validated using the existing experimental data.The overall energy-saving of the offices over a full year were analyzed using the validated model.Results demonstrated that for SLHS with the area of 40 m^(2),the rate of the energy saving in the offices due to lighting and hot water systems were 58.9%,and 19.3%,respectively.The system also had the additional benefit of reducing the cooling load of the air conditioning system during summer period together with improving the quality of the indoor environment resulting in better health and productivity of the occupants.展开更多
Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger a...Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.展开更多
At the scheme design stage,the potential of daylighting is significant due to the saving for electric lighting use. There are few simple tools for architects to optimize the daylighting design. Therefore,it is useful ...At the scheme design stage,the potential of daylighting is significant due to the saving for electric lighting use. There are few simple tools for architects to optimize the daylighting design. Therefore,it is useful to develop a design guideline related to the evaluation of lighting energy saving potential and sunlight design strategies. This paper analyzes the impacts of different artificial lighting control methods and design parameters on daylighting. A direct correlation between lighting energy consumption and parameters such as orientations,window to wall ratio (WWR) and perimeter depth is established. A simplified prediction model is proposed to estimate lighting energy consumption with the given perimeter depth,WWR,and window transparency. Validation of the model is carried out compared with detailed lighting simulation software for an office building. After the variation analysis for these parameters,design advises for the daylighting design at scheme design phase are summarized.展开更多
Applying energy-saving measures in residential buildings is usually constrained by the increase of initial investment. "However, if it is analyzed from the view of energy cost and life-cycle cost, the energy-saving b...Applying energy-saving measures in residential buildings is usually constrained by the increase of initial investment. "However, if it is analyzed from the view of energy cost and life-cycle cost, the energy-saving benefit can offset ~he increase of initial investment. An analysis method based on life-cycle concept was developed to calcu- late the energy cost of residential building flats. Several uncertain factors were included into the model, making it more accurate to reflect practical situation. The model was solved using the software DeST and applied to one resi- dential building project in Shanghai. The case study shows that the initial investment (cost) is paid back during the operational phase through less consumption of energy. It further indicates that the investment recovery period is between 10 and 19 years which are acceptable to households and developers in China.展开更多
It is necessary for China to refocus its energy conservation effort from the industrial sector (field) to all three sectors simultaneously, i.e. industry, construction and transport. In addition, it should also make s...It is necessary for China to refocus its energy conservation effort from the industrial sector (field) to all three sectors simultaneously, i.e. industry, construction and transport. In addition, it should also make significant effort for conserving energy on general technical equipment that are used in large quantities and for a variety of applications. Therefore, there is a need to integrate industrial, construction and transport sectors, i.e. the integration between key technologies and widely used technologies, between hard and soft management, between energy-saving technologies and comprehensive resource utilization technologies. According to estimates, if China’s energy consuming sectors adopted appropriate energy-saving technologies, total energy-savings (using 2010 as the baseline) would be 200 million, 450 million, 650 million and 800 million tons of standard coal in 2015, 2020, 2025 and 2030, respectively.展开更多
The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study poi...The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study points:1)The multiple events are merged into a single event;2)the high-order mode is changed to the low-order mode.For this rea⁃son,we seek that multiple events in wireless transmission links are fused into a single event from Shannon formulas.We also analyze the relationship between the information modula⁃tion and the error correction,and give a fusion structure of error-corrected modulation.The energy-saving performance of the error-corrected modulation method is further analyzed through comparison with the traditional methods of modulation plus error correction.The re⁃sults of numerical analysis demonstrate the wireless energy saving methods for wireless sys⁃tems based on Shannon formulas are the achievable efficient schemes.展开更多
The Yangtze River Basin in China is characterised by hot-and cold-humid climates in summer and winter, respectively. Thus, increased demand for heating and cooling energy according to the season, as well as poor indoo...The Yangtze River Basin in China is characterised by hot-and cold-humid climates in summer and winter, respectively. Thus, increased demand for heating and cooling energy according to the season, as well as poor indoor thermal comfort, are inevitable. To overcome this problem, this study focused on the influence of passive design and heating, ventilation, and air conditioning equipment performance on the energy performance of residential buildings, and explored potential energy-saving technology paths involving passive design and improved coefficient of performance through a multi-objective and multi-parameter optimisation technique. A large-scale questionnaire survey covering a typical city was first conducted to identify family lifestyle patterns regarding time spent at home, family type, air conditioner use habits, indoor thermal comfort, etc. Then, the actual heating and cooling energy consumption and information of model building were determined for this region. Subsequently, the design parameters of an individual building were simulated using Energyplus to investigate the cooling and heating energy consumption for a typical residential building with an air conditioner. The results indicated an improvement of approximately 30% in energy efficiency through optimisation of the external-wall insulation thickness and the external-window and shading performance, and through use of appropriate ventilation technology. Thus, a multi-objective and multi-parameter optimisation model was developed to achieve comprehensive optimisation of several design parameters. Experimental results showed that comprehensive optimisation could not only reduce cooling and heating energy consumption, but also improve the thermal comfort level achieved with a non-artificial cooling and heating source. Finally, three energy-saving technology paths were formulated to achieve a balance between indoor thermal comfort improvement and the target energy efficiency(20 kWh/(m2?a)). The findings of this study have implications for the future design of buildings in the Yangtze River Basin, and for modification of existing buildings for improved energy efficiency.展开更多
Building retrofit procedures play a crucial role in improving the energy performance and economic indicators of a building.In this context,an energy audit is typically recommended,but it is seldom used as a comprehens...Building retrofit procedures play a crucial role in improving the energy performance and economic indicators of a building.In this context,an energy audit is typically recommended,but it is seldom used as a comprehensive approach due to the complexity and associated costs.This article aims to conduct a holistic energy audit approach for a university building in Malaysia,with the objective of diagnosing energy efficiency deficiencies,identifying areas of energy waste and proposing practical retrofit measures accordingly.The approach involved multiple stages,including measurements,surveys and simulation work.Eight energy-saving measures were proposed,targeting improvements in envelope elements,cooling and lighting systems,and operation and control.The Design-Builder software was utilized for energy simulation,assessing the annual energy savings.Economic evaluation indices,such as net present value and simple payback period,were used to assess the economic feasibility of the measures.The results demonstrated significant potential for energy reduction,with each measure achieving annual energy reductions ranging from 2%to 18%,and a cumulative im-pact of 41%on annual energy consumption when combined.The investment payback period for the energy-saving measures varied from 0.8 to 8.9 years,with a payback period of 3.9 years for the combined energy-saving measures.Furthermore,the net present value was positive,indicating the economic feasibility of investing in the proposed energy-saving measures.These findings provide valu-able energy-saving opportunities that can be applied to improve similar buildings on the university campus.展开更多
Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industr...Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industry is its huge energy consumption and carbon emissions, but the development of a comprehensive energy consumption assessment has lagged. Here, a comprehensive energy consumption and carbon emission model suitable for hospitality is established, using comprehensive data collected for hotels over six years and with reference to general international methods, decomposition analysis methods as recommended by the IPCC, and related standards in China. Our study shows that the maximum comparable unit energy consumption per building area among four- and five-star hotels is 73.26 kg ce m-2 y-l. Through energy-saving reconstruction, the comprehensive energy consumption of five-star hotels has declined by 4.1% in six years and is smaller than the advanced comparable value of 55 kg ce m2 y4. The comparable unit energy consumption per area building of most two- and three-star hotels (53 kg ce m2 y-l) is higher than the reasonable value. There are large numbers of hotels of this type in China and the potential energy savings are huge. Analyzing factors of energy consumption, we found that indirect carbon emissions from electricity usage are the most significant. From an energy consumption structural perspective, Heating, Ventilation and Air Conditioning (HVAC) System accounts for most energy consumption. This research provides a foundation for further examination of energy-savings, emission reduction plans and Monitoring Reporting Verification (MRV) in the hospitality sector.展开更多
Precision energy management is very important for sustainability development of solar greenhouses,since huge energy demand for agricultural production both in quantity and quality.A proactive energy management,accordi...Precision energy management is very important for sustainability development of solar greenhouses,since huge energy demand for agricultural production both in quantity and quality.A proactive energy management,according to the optimal energy utilization in a look-ahead period with weather prediction,is presented and tested in this research.A multi-input-multi-output linear model of the energy balance of solar greenhouses based on on-line identification system can simulate greenhouse behavior and allow for predictive control.The good time allocation of available solar energy can be achieved by intelligent use of controls,such as store/retrieve fans and ventilation windows,i.e.solar energy to warm up the air or to be stored in the storage elements(wall,soil,etc.)or to be exhausted to outside.The proactive energy management can select an optimal trajectory of air temperature for the forecasted weather period to minimize plants’thermal‘cost’defined by an‘expert’in terms of set-points for the specific crop.The selection of temperature trajectory is formulated as a generalized traveling salesman problem(GTSP)with precedence constraints and is solved by a genetic algorithm(GA)in this research.The simulation study showed good potential for energy saving and timely allocation to prevent excessive crop stress.The active control elements in addition to predefining and applying,within energy constraints,optimal climate in the greenhouse,it also reduces the energy deficit,i.e.the working hours of the‘heater’in the sustained freezing weather,as well as the ventilation hours,that is,more energy harvest in the warm days.This intelligent solar greenhouse management system is being migrated to the web for serving a‘customer base’in the Internet Plus era.The capacity,of the concrete ground CAUA system(CAUA is an abbreviations from both China Agricultural University and Agricultural University of Athens),to implement web‘updates’of criteria,open weather data and models,on which control actions are based,is what makes use of Cloud Data for closing the loop of an effective Internet of Things(IoT)system,based on MACQU(MAnagement and Control for QUality)technological platform.展开更多
The transportation buildings alongside the expressways(TBE)have comprehensive characteristics,providing shopping and accommodations for drivers and passengers.However,the indoor thermal environment and energy consumpt...The transportation buildings alongside the expressways(TBE)have comprehensive characteristics,providing shopping and accommodations for drivers and passengers.However,the indoor thermal environment and energy consumption of such service buildings was not covered in most studies.To this end,based on some typical TBEs,this study investigated the thermal environment and energy consumption characteristics for TBEs.And the men-tioned TBEs are located in Xiong’an New Area,a national special zone with requirements of low carbon and low energy consumption in China’s cold region.The thermal environment study included questionnaire survey and on-site investigation by adopting dynamic thermal comfort evaluation index(i.e.,Relative Warmth Index(RWI)and Heat Deficit Rate(HDR)).Then,the TBE energy consumption was investigated with the main influencing factor analyses.Finally,numerical simulations were conducted to analyze the energy efficiency approaches in TBE.The results showed that RWI and HDR were able to evaluate the thermal comfort of personnel in transi-tional environment of TBE in winter.Meanwhile,when the room temperature was set as 16℃,it was still able to maintain the thermal environment for the indoor staff.The main energy influencing factors of TBEs are building scale,system equipment and usage characteristics.Besides,it was practicable to adopt the heat pump system to replace conventional space heating and cooling system,of which the total energy consumption of geothermal heat pump reduced by 38.1%.展开更多
The essential requirements for evaluating the sustainable development of a system and the thermodynamic framework of the energy conservation mechanism in the waste-removal process are proposed.A thermodynamic method o...The essential requirements for evaluating the sustainable development of a system and the thermodynamic framework of the energy conservation mechanism in the waste-removal process are proposed.A thermodynamic method of analysis based on the first and second laws of thermodynamics is suggested as a means to analyze the theoretical energy consumption for the removal of organic contaminants by physical methods.Moreover,the theoretical energy consumption for the removal by physical methods of different kinds of representative organic contaminants with different initial concentrations and amounts is investigated at 298.15 K and 1.01325 × 105 Pa.The results show that the waste treatment process has a high energy consumption and that the theoretical energy consumption for the removal of organic contaminants increases with the decrease of their initial concentrations in aqueous solutions.The theoretical energy consumption for the removal of different organic contaminants varies dramatically.Furthermore,the theoretical energy consumption increases greatly with the increase in the amount to be removed.展开更多
Rural residents have unique lifestyle characteristics,energy consumption methods,energy-saving behaviors,and awareness.And the direct carbon emission from rural residents is based on the combined effect of multiple fa...Rural residents have unique lifestyle characteristics,energy consumption methods,energy-saving behaviors,and awareness.And the direct carbon emission from rural residents is based on the combined effect of multiple factors.In order to address the complexity of factors affecting the direct carbon emissions from rural household,this study used a structural equation model to examine the effect of multi-factor variables on direct carbon emissions from rural households in central China.Data were collected using questionnaires and surveys in six cities in central China to reflect the daily reality of rural residents.The results show that quality of life and awareness of energy conservation can affect the direct carbon emissions of rural residents.Family characteristics and awareness of energy conservation affected carbon emissions indirectly by affecting the daily behaviors and quality of life of the residents;consumption characteristics,energy-saving behaviors,and energy conservation policies are not the main factors contributing to the direct carbon emissions of the residents.Based on the results,future studies can focus on energy conservation education,improvement of the living habits,coal energy use efficiency,and energy consumption structure of residences.展开更多
基金This work was financially supported by the Key Technologies R&D Programme of Tianjin(06YFGZGX02400).
文摘Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were investigated by OCA30 automatic contact angle test instrument,metallography microscope and XRD instrument etc.Results suggests:adding alloy element to Cu may increase its surface free energy,and the more kinds of alloy elements are added,the more surface free energy increases;the alloy element Sn an increase the surface free energy of Cu-Zn alloy;Cu-Zn alloy with fir-tree crystal structure,great phase discrepancy and obvious composition aliquation has greater surface free energy;Cu-Zn alloy with compounds and serious surface crystal lattice distortion has greater surface free energy.
文摘Many researches discussing reduced energy consumption for environmental protection focus on machine efficiency or process redesign. To optimize the machine operation time can also save the energy, and these researches have received great interests in recent years. This study considers three different states of machines, among processing there are two different speeds, to solve the problem of minimizing energy costs under time-of-use tariff with no tardy jobs in flexible flow shop. This problem is basically NP-hard, we proposed a hybrid genetic algorithm (GA) to solve problems in reasonable timeliness. The result shows that to optimize different states of machines under time-of use tariff can reduce energy costs significantly in on-time delivery.
文摘It is researched that rural residential buildings in Heilongjieng consume high energy and the living environment is poor. The research aimed at designing low-carbon and energy-saving buildings in order to reduce energy consumption by applying energy storage. Besides, the research used composite solar panel, waste- based inorganic foam materials, and polystyrene board as construction materials and integrated energy collection, living environment and farming by energy storage system. It is notable that the research would reduce pollution on environment caused by residential buildings, which coincides with national economy development and en- ergy strategy, promoting construction material industry development, with high social and economic benefits.
基金supported by the National Natural Science Foundation of China(The key trusted running technologies for the sensing nodes in Internet of things: 61501007The outstanding personnel training program of Beijing municipal Party Committee Organization Department (The Research of Trusted Computing environment for Internet of things in Smart City: 2014000020124G041
文摘According to the high operating costs and a large number of energy waste in the current data center network architectures, we propose a kind of trusted flow preemption scheduling combining the energy-saving routing mechanism based on typical data center network architecture. The mechanism can make the network flow in its exclusive network link bandwidth and transmission path, which can improve the link utilization and the use of the network energy efficiency. Meanwhile, we apply trusted computing to guarantee the high security, high performance and high fault-tolerant routing forwarding service, which helps improving the average completion time of network flow.
文摘A ceramic gas turbine can save energy because of its high thermal efficiency at high turbine inlet temperatures. This paper deals with the thermodynamic and economic aspects of a ceramic gas turbine cogeneration system. Here cogeneration means the simultaneous production of electrical en-ergy and useful thermal energy from the same facility. The thermodynamic performance of a ceramic gas turbine cycle is assessed using a computer model. This model is used in parametric studies of performance under partial loads and at various inlet air temperatures. The computed performance is compared to the measured performance of a conventional gas turbine cycle. Then, an economic evaluation of a ceramic gas turbine cogeneration system is investigated. Energy savings provided by this system are estimated on the basis of the distributions of heat/power ratios. The computed economic evaluation is compared to the actual economic performance of a conventional system in which boilers produce the required thermal energy and electricity is purchased from a utility.
文摘The rapid development of China’s automobile industry has brought ever-increasing impact on resources,energy and environment,the energy-saving and new energy vehicles come into being accordingly.This article firstly systematically introduces the technical route of energy-saving and new energy vehicles of China,focusing on the key bottleneck problems arising from the construction process of current assessment system of the technical route for energy-saving and new energy vehicles,establishes the energy-saving and new energy vehicle business model assessment index system afterward based on the comparative analysis on energy-saving and new energy vehicle business assessment model and the full life cycle theory,and finally makes prospects and forecasts on vital problems of system boundary,dynamic optimization,simulation system of full life cycle assessment of energy-saving and new energy vehicle.
文摘This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.
基金The authors gratefully acknowledge the funding support from the Natural Science Foundation of Heilongjiang Province(No.YQ2020E019).
文摘The performance of a solar lighting and heating system(SLHS)based on the spectral splitting effect of nanofluids is presented in this paper.SLHS through nanofluids would split the sunlight spectrum into different wavelength,and then introduce the visible light into the offices for lighting and absorb infrared energy to generate hot water.The Energy Plus software was used to analyze the energy consumption of typical office building located in the city of Harbin in China coupled with SLHS.Based on the simulation results two lighting zones were identified in the offices and the optimal lighting control strategy was developed for a full year.The performance models of SLHS with different light-receiving areas of 10 m^(2)and 40 m^(2)were simulated and validated using the existing experimental data.The overall energy-saving of the offices over a full year were analyzed using the validated model.Results demonstrated that for SLHS with the area of 40 m^(2),the rate of the energy saving in the offices due to lighting and hot water systems were 58.9%,and 19.3%,respectively.The system also had the additional benefit of reducing the cooling load of the air conditioning system during summer period together with improving the quality of the indoor environment resulting in better health and productivity of the occupants.
基金supported by National Natural Science Foundation of China(Grant No. 50875233)National Hi-tech Research and Development Program of China(863 Program, Grant No. 2010AA044401)+3 种基金Open Fund of the State Key Lab of Flow Power Transmission and Control(Grant No. GZKF-201111)National Youth Science Foundofion of China(Grant No. 51205140)Fundamental Research Funds for the Central University of China(Grant No. JB-ZR1208)Scientific Research Funds of Huaqiao University, China(Grant No. 11BS409)
文摘Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.
基金Project(2006BAJ02A02) supported by the National Key Technologies R & D Program of China
文摘At the scheme design stage,the potential of daylighting is significant due to the saving for electric lighting use. There are few simple tools for architects to optimize the daylighting design. Therefore,it is useful to develop a design guideline related to the evaluation of lighting energy saving potential and sunlight design strategies. This paper analyzes the impacts of different artificial lighting control methods and design parameters on daylighting. A direct correlation between lighting energy consumption and parameters such as orientations,window to wall ratio (WWR) and perimeter depth is established. A simplified prediction model is proposed to estimate lighting energy consumption with the given perimeter depth,WWR,and window transparency. Validation of the model is carried out compared with detailed lighting simulation software for an office building. After the variation analysis for these parameters,design advises for the daylighting design at scheme design phase are summarized.
基金The Research on Key Technologies of Sustainable Building and Their Demonstration,Shanghai Commission of Science of Technol-ogy(No03dz12009)
文摘Applying energy-saving measures in residential buildings is usually constrained by the increase of initial investment. "However, if it is analyzed from the view of energy cost and life-cycle cost, the energy-saving benefit can offset ~he increase of initial investment. An analysis method based on life-cycle concept was developed to calcu- late the energy cost of residential building flats. Several uncertain factors were included into the model, making it more accurate to reflect practical situation. The model was solved using the software DeST and applied to one resi- dential building project in Shanghai. The case study shows that the initial investment (cost) is paid back during the operational phase through less consumption of energy. It further indicates that the investment recovery period is between 10 and 19 years which are acceptable to households and developers in China.
文摘It is necessary for China to refocus its energy conservation effort from the industrial sector (field) to all three sectors simultaneously, i.e. industry, construction and transport. In addition, it should also make significant effort for conserving energy on general technical equipment that are used in large quantities and for a variety of applications. Therefore, there is a need to integrate industrial, construction and transport sectors, i.e. the integration between key technologies and widely used technologies, between hard and soft management, between energy-saving technologies and comprehensive resource utilization technologies. According to estimates, if China’s energy consuming sectors adopted appropriate energy-saving technologies, total energy-savings (using 2010 as the baseline) would be 200 million, 450 million, 650 million and 800 million tons of standard coal in 2015, 2020, 2025 and 2030, respectively.
基金This work was supported by National Natural Science Foundation of Chi⁃na(NSFC)under Grant No.61631018.
文摘The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study points:1)The multiple events are merged into a single event;2)the high-order mode is changed to the low-order mode.For this rea⁃son,we seek that multiple events in wireless transmission links are fused into a single event from Shannon formulas.We also analyze the relationship between the information modula⁃tion and the error correction,and give a fusion structure of error-corrected modulation.The energy-saving performance of the error-corrected modulation method is further analyzed through comparison with the traditional methods of modulation plus error correction.The re⁃sults of numerical analysis demonstrate the wireless energy saving methods for wireless sys⁃tems based on Shannon formulas are the achievable efficient schemes.
基金supported by the National Key R&D Programme “Solutions to Heating and Cooling of Buildings in the Yangtze River Region” (Grant No: 2016YFC0700301)the UK-China collaborative research project “Low carbon climate-responsive Heating and Cooling of Cities (LoHCool)” supported by the National Natural Science Foundation of China (NSFC Grant No. 51561135002)+1 种基金UK Engineering and Physical Sciences Research Council (EPSRC Grant No. EP/N009797/1)the China Scholarship Council (CSC) for one-year study at the University of Cambridge
文摘The Yangtze River Basin in China is characterised by hot-and cold-humid climates in summer and winter, respectively. Thus, increased demand for heating and cooling energy according to the season, as well as poor indoor thermal comfort, are inevitable. To overcome this problem, this study focused on the influence of passive design and heating, ventilation, and air conditioning equipment performance on the energy performance of residential buildings, and explored potential energy-saving technology paths involving passive design and improved coefficient of performance through a multi-objective and multi-parameter optimisation technique. A large-scale questionnaire survey covering a typical city was first conducted to identify family lifestyle patterns regarding time spent at home, family type, air conditioner use habits, indoor thermal comfort, etc. Then, the actual heating and cooling energy consumption and information of model building were determined for this region. Subsequently, the design parameters of an individual building were simulated using Energyplus to investigate the cooling and heating energy consumption for a typical residential building with an air conditioner. The results indicated an improvement of approximately 30% in energy efficiency through optimisation of the external-wall insulation thickness and the external-window and shading performance, and through use of appropriate ventilation technology. Thus, a multi-objective and multi-parameter optimisation model was developed to achieve comprehensive optimisation of several design parameters. Experimental results showed that comprehensive optimisation could not only reduce cooling and heating energy consumption, but also improve the thermal comfort level achieved with a non-artificial cooling and heating source. Finally, three energy-saving technology paths were formulated to achieve a balance between indoor thermal comfort improvement and the target energy efficiency(20 kWh/(m2?a)). The findings of this study have implications for the future design of buildings in the Yangtze River Basin, and for modification of existing buildings for improved energy efficiency.
基金The authors would like to thank the maintenance department(Pejabat Harta Bina)and express their appreciation for the assistance received from the E07 block staff at the College of Mechanical Engineering at Universiti Teknologi Malaysia(UTM)during the survey and measurement processes.Lastly,the authors would like to acknowledge and appreciate the support provided by UTM.
文摘Building retrofit procedures play a crucial role in improving the energy performance and economic indicators of a building.In this context,an energy audit is typically recommended,but it is seldom used as a comprehensive approach due to the complexity and associated costs.This article aims to conduct a holistic energy audit approach for a university building in Malaysia,with the objective of diagnosing energy efficiency deficiencies,identifying areas of energy waste and proposing practical retrofit measures accordingly.The approach involved multiple stages,including measurements,surveys and simulation work.Eight energy-saving measures were proposed,targeting improvements in envelope elements,cooling and lighting systems,and operation and control.The Design-Builder software was utilized for energy simulation,assessing the annual energy savings.Economic evaluation indices,such as net present value and simple payback period,were used to assess the economic feasibility of the measures.The results demonstrated significant potential for energy reduction,with each measure achieving annual energy reductions ranging from 2%to 18%,and a cumulative im-pact of 41%on annual energy consumption when combined.The investment payback period for the energy-saving measures varied from 0.8 to 8.9 years,with a payback period of 3.9 years for the combined energy-saving measures.Furthermore,the net present value was positive,indicating the economic feasibility of investing in the proposed energy-saving measures.These findings provide valu-able energy-saving opportunities that can be applied to improve similar buildings on the university campus.
基金Key Discipline Project of Shanghai Municipal Education Commission(No.J50402)Key Research of Shanghai Institute of Tourism(No.RS2015-B3)
文摘Recent years have witnessed a rapid development of star-rated hotels in China, especially high- end star-rated hotels. Consequently, there are now approximately12 000 hotels in China. One bottleneck within the industry is its huge energy consumption and carbon emissions, but the development of a comprehensive energy consumption assessment has lagged. Here, a comprehensive energy consumption and carbon emission model suitable for hospitality is established, using comprehensive data collected for hotels over six years and with reference to general international methods, decomposition analysis methods as recommended by the IPCC, and related standards in China. Our study shows that the maximum comparable unit energy consumption per building area among four- and five-star hotels is 73.26 kg ce m-2 y-l. Through energy-saving reconstruction, the comprehensive energy consumption of five-star hotels has declined by 4.1% in six years and is smaller than the advanced comparable value of 55 kg ce m2 y4. The comparable unit energy consumption per area building of most two- and three-star hotels (53 kg ce m2 y-l) is higher than the reasonable value. There are large numbers of hotels of this type in China and the potential energy savings are huge. Analyzing factors of energy consumption, we found that indirect carbon emissions from electricity usage are the most significant. From an energy consumption structural perspective, Heating, Ventilation and Air Conditioning (HVAC) System accounts for most energy consumption. This research provides a foundation for further examination of energy-savings, emission reduction plans and Monitoring Reporting Verification (MRV) in the hospitality sector.
基金This research was supported by the National Key Research and Development Program of China(2016YED0201003)the Yunnan Academician Expert Workstation(Wang Maohua,Grant No.2015IC16)。
文摘Precision energy management is very important for sustainability development of solar greenhouses,since huge energy demand for agricultural production both in quantity and quality.A proactive energy management,according to the optimal energy utilization in a look-ahead period with weather prediction,is presented and tested in this research.A multi-input-multi-output linear model of the energy balance of solar greenhouses based on on-line identification system can simulate greenhouse behavior and allow for predictive control.The good time allocation of available solar energy can be achieved by intelligent use of controls,such as store/retrieve fans and ventilation windows,i.e.solar energy to warm up the air or to be stored in the storage elements(wall,soil,etc.)or to be exhausted to outside.The proactive energy management can select an optimal trajectory of air temperature for the forecasted weather period to minimize plants’thermal‘cost’defined by an‘expert’in terms of set-points for the specific crop.The selection of temperature trajectory is formulated as a generalized traveling salesman problem(GTSP)with precedence constraints and is solved by a genetic algorithm(GA)in this research.The simulation study showed good potential for energy saving and timely allocation to prevent excessive crop stress.The active control elements in addition to predefining and applying,within energy constraints,optimal climate in the greenhouse,it also reduces the energy deficit,i.e.the working hours of the‘heater’in the sustained freezing weather,as well as the ventilation hours,that is,more energy harvest in the warm days.This intelligent solar greenhouse management system is being migrated to the web for serving a‘customer base’in the Internet Plus era.The capacity,of the concrete ground CAUA system(CAUA is an abbreviations from both China Agricultural University and Agricultural University of Athens),to implement web‘updates’of criteria,open weather data and models,on which control actions are based,is what makes use of Cloud Data for closing the loop of an effective Internet of Things(IoT)system,based on MACQU(MAnagement and Control for QUality)technological platform.
基金supported by National Natural Science Foundation of China(Project No.51978231)Natural Science Foundation of Hebei Province(Project No.E2017202136)+1 种基金Hebei Province Funding Project for Returned Scholars,China(Project No.C20190507)Research and Development Project of MOHURD,China(Project No.2018-K11-001).
文摘The transportation buildings alongside the expressways(TBE)have comprehensive characteristics,providing shopping and accommodations for drivers and passengers.However,the indoor thermal environment and energy consumption of such service buildings was not covered in most studies.To this end,based on some typical TBEs,this study investigated the thermal environment and energy consumption characteristics for TBEs.And the men-tioned TBEs are located in Xiong’an New Area,a national special zone with requirements of low carbon and low energy consumption in China’s cold region.The thermal environment study included questionnaire survey and on-site investigation by adopting dynamic thermal comfort evaluation index(i.e.,Relative Warmth Index(RWI)and Heat Deficit Rate(HDR)).Then,the TBE energy consumption was investigated with the main influencing factor analyses.Finally,numerical simulations were conducted to analyze the energy efficiency approaches in TBE.The results showed that RWI and HDR were able to evaluate the thermal comfort of personnel in transi-tional environment of TBE in winter.Meanwhile,when the room temperature was set as 16℃,it was still able to maintain the thermal environment for the indoor staff.The main energy influencing factors of TBEs are building scale,system equipment and usage characteristics.Besides,it was practicable to adopt the heat pump system to replace conventional space heating and cooling system,of which the total energy consumption of geothermal heat pump reduced by 38.1%.
基金supported by the Chinese National Key Technology Research and Development Program (2006AA03Z455)National Basic Research Program of China (No 2009CB226103)+2 种基金the National Natural Science Foundation of China (20976080)NSFC-RGC (No 20731160614)the Program for Changjiang Scholars and Innovative Research Teams in University (No IRT0732)
文摘The essential requirements for evaluating the sustainable development of a system and the thermodynamic framework of the energy conservation mechanism in the waste-removal process are proposed.A thermodynamic method of analysis based on the first and second laws of thermodynamics is suggested as a means to analyze the theoretical energy consumption for the removal of organic contaminants by physical methods.Moreover,the theoretical energy consumption for the removal by physical methods of different kinds of representative organic contaminants with different initial concentrations and amounts is investigated at 298.15 K and 1.01325 × 105 Pa.The results show that the waste treatment process has a high energy consumption and that the theoretical energy consumption for the removal of organic contaminants increases with the decrease of their initial concentrations in aqueous solutions.The theoretical energy consumption for the removal of different organic contaminants varies dramatically.Furthermore,the theoretical energy consumption increases greatly with the increase in the amount to be removed.
基金supported by the National Natural Science Foundation of China(71573015,71521002)the National Key Research and Development Program of China(2016YFA0602801).
文摘Rural residents have unique lifestyle characteristics,energy consumption methods,energy-saving behaviors,and awareness.And the direct carbon emission from rural residents is based on the combined effect of multiple factors.In order to address the complexity of factors affecting the direct carbon emissions from rural household,this study used a structural equation model to examine the effect of multi-factor variables on direct carbon emissions from rural households in central China.Data were collected using questionnaires and surveys in six cities in central China to reflect the daily reality of rural residents.The results show that quality of life and awareness of energy conservation can affect the direct carbon emissions of rural residents.Family characteristics and awareness of energy conservation affected carbon emissions indirectly by affecting the daily behaviors and quality of life of the residents;consumption characteristics,energy-saving behaviors,and energy conservation policies are not the main factors contributing to the direct carbon emissions of the residents.Based on the results,future studies can focus on energy conservation education,improvement of the living habits,coal energy use efficiency,and energy consumption structure of residences.