Like in other sectors of activity, the sustainability in refrigeration systems is a mandatory goal to achieve, namely at house holdings, bars and restaurants, where small-scale refrigerators and freezers are widely us...Like in other sectors of activity, the sustainability in refrigeration systems is a mandatory goal to achieve, namely at house holdings, bars and restaurants, where small-scale refrigerators and freezers are widely used. The aim of this work is to demonstrate experimentally, trough measurements carried out in these equipments, the improvement that can be achieved if several modifications are implemented in traditional household refrigeration systems. In addition, it was also simulated and analysed experimentally a slightly different equipment, a refrigeration system used for draught beverages. Both systems work on a single vapour compression refrigeration with R-134a as working fluid. In the end, by implemented the modifications tested in the virtual model, it was possible to improve their thermal behaviour, a decrease in electrical energy consumption, as well as, the associated CO2 emissions reduction can be attained. In this project, the CFD （Computational Fluid Dynamics） soffware--ANSYS Fluent was used to simulate the ambient temperature and velocity fields inside the refrigerator and in that way to validate the measured results.展开更多
Based on the Chinese thermal coal and power generation data,such as ultimate analysis,proximate analysis,low heat value(LHV)on as received basis,power generation volume,thermal coal consumption volume and net coal con...Based on the Chinese thermal coal and power generation data,such as ultimate analysis,proximate analysis,low heat value(LHV)on as received basis,power generation volume,thermal coal consumption volume and net coal consumption rate,several mathematical models for calculating CO 2 reduction by Chinese coal-fired power plants are established.Calculations of the CO 2 emission factor(CEF),the CO 2 emission volume and reduction volume are made according to these models.The calculation results reveal that between 1993 and 2010,the CO 2 emission volume reached 31.069 Gt,reduced by 0.439 Gt,averaging 28.83 Mt each year.展开更多
Due to ongoing growth in carbon emission, many governments＇ have taken measures to curb it. Thus, it is of great importance to measure carbon emissions in international trade and probe into the causes behind them. Th...Due to ongoing growth in carbon emission, many governments＇ have taken measures to curb it. Thus, it is of great importance to measure carbon emissions in international trade and probe into the causes behind them. This paper first applies inputoutput model then it estimates the carbon emissions embodied in China＇s international trade in 2002, 2005 and 2007. Using structural decomposition analysis, this paper measures carbon emissions in international trade by their scale effect, composition effect and intensity effect. Our results illustrate： （1） a rapidly-rising net export of carbon emissions for China, and （2） scale effect and composition effect stimulates carbon emissions embodied in exports, while intensity effect discourages it.展开更多
Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a...Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a formula that was applicable to carbon-emission calculation, and discussed carbon-emission characteristics of concrete structures and steel construction.Owing to the difference of electrical and mechanical equipment used in construction phase, the results show that under the same conditions, the carbon emission intensity of a concrete structure building is much higher than that of a steel building.At last, we also put forward some emission reduction measures based on the calculation data of different buildings.展开更多
The objective of this research is to quantify the EEC （embodied energy/CO2） of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building＇s life-cycle, such as constr...The objective of this research is to quantify the EEC （embodied energy/CO2） of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building＇s life-cycle, such as construction （including manufacture of materials and equipment）, renewal （including repair work） and demolition. Energy and CO2 emission intensities in terms of 401 sectors were calculated, using the 2005 I-O （input-output） table in Japan. According to our case study conducted from the construction phase to demolition, the EC （embodied CO2） of an office building used for 60 years is 12,044 t-CO2 and 1,093 kg-CO2/m^2 in total. CO2 equivalent emissions （CO2e） by Freon gases, contained in building materials, equipment and devices, were also calculated. As the results, CO2e by insulators was 2% of the building＇s EC and CO2e by refrigerants was 9%-12% of the building＇s EC. It is important to keep reducing emissions of Freon gases contained in refrigerators.展开更多
The study on greenhouse gas inventory in urban China lags far behind the global level. The important factor that curbs the carbon inventory of cities of China is inventory methodology and scope. Given the insufficienc...The study on greenhouse gas inventory in urban China lags far behind the global level. The important factor that curbs the carbon inventory of cities of China is inventory methodology and scope. Given the insufficiency of Chinese cities carbon inventory, a system and accounting model （scopel＋ scope2） as well as principles and boundaries were proposed for China. The carbon emissions in scopel and scopel＋ scope2 were calculated in Chinese prefecture-level cities. The EDGAR dataset was used for the calculation of scopel carbon emissions in cities in China and the level of uncertainty was analyzed as well. The results showed that the direct carbon emission of cities in China was about 31.65% of China total emissions. The scopel＋ scope2 carbon emissions in cities of China were calculated based on the GIS and RS model. The results showed that the sum of direct （scopel） and indirect （scope2） carbon emissions of cities in China accounted for 38.80% of total China carbon emissions.展开更多
We evaluate economic and environmental impacts of climate change mitigation in a country scale considering various time horizons in the analysis applying a single-country dynamic computable general equilibrium model w...We evaluate economic and environmental impacts of climate change mitigation in a country scale considering various time horizons in the analysis applying a single-country dynamic computable general equilibrium model with endogenous technological change. Although there is a possibility that Gross Domestic Product （GDP） becomes larger for the abatement cases than the baseline case in the earlier years, it tends to be lower than that in the later years. The longer the time horizon and/or the more severe the abatement, the larger the negative impacts will be. When subsidizing R＆D investment, increase in GDP compared to the baseline case is realized in the middle of the time horizon, and the larger increase tends to be observed for the longer-term cases. These results would be due to technological change induced by the subsidies and emission abatement. Environmental indicators are also improved. We showed that the results were influenced by the target time horizon when using an intertemporal dynamic model.展开更多
The determination of carbon emission from foundation pit engineering is a tough and complex project owing to its characteristics including large material consumption,short use time,difficult recycling and no operation...The determination of carbon emission from foundation pit engineering is a tough and complex project owing to its characteristics including large material consumption,short use time,difficult recycling and no operation stage.To overcome these limitations,the calculation boundary and calculation method for carbon emission of foundation pit project are defined in this paper,which is successfully applied in the carbon emission analysis of the actual engineering project,i.e.the construction of large-scale foundation pit of Kunming comprehensive transportation international hub.All the carbon emissions coresponding to four working stages including building materials production,building materials transportation,construction and demolition were calculated and anatomized.The results revealed that the content of CO_(2) released in the stage of building materials production accounts for 89.3%of the total carbon emission,which means the amount of building materials consumed in the engineering project is the crucial factor to control the carbon emission.Besides,two kinds of carbon reduction measures,i.e.optimization design of support scheme and recycling waste materials of internal support demolition,were explored by analyzing the proportion and average value of carbon emission from different sub project of the support structure.A pronounced effect of carbon reduction was achieved.Furthermore,both a fast calculation method of carbon emission factor of unit work volume and general carbon reduction measures are proposed in this paper,which could provide a reference and new viewpoint for the engineers and designers to calculate and analyze the carbon emission and to take effective carbon reduction measures.展开更多
文摘Like in other sectors of activity, the sustainability in refrigeration systems is a mandatory goal to achieve, namely at house holdings, bars and restaurants, where small-scale refrigerators and freezers are widely used. The aim of this work is to demonstrate experimentally, trough measurements carried out in these equipments, the improvement that can be achieved if several modifications are implemented in traditional household refrigeration systems. In addition, it was also simulated and analysed experimentally a slightly different equipment, a refrigeration system used for draught beverages. Both systems work on a single vapour compression refrigeration with R-134a as working fluid. In the end, by implemented the modifications tested in the virtual model, it was possible to improve their thermal behaviour, a decrease in electrical energy consumption, as well as, the associated CO2 emissions reduction can be attained. In this project, the CFD （Computational Fluid Dynamics） soffware--ANSYS Fluent was used to simulate the ambient temperature and velocity fields inside the refrigerator and in that way to validate the measured results.
文摘Based on the Chinese thermal coal and power generation data,such as ultimate analysis,proximate analysis,low heat value(LHV)on as received basis,power generation volume,thermal coal consumption volume and net coal consumption rate,several mathematical models for calculating CO 2 reduction by Chinese coal-fired power plants are established.Calculations of the CO 2 emission factor(CEF),the CO 2 emission volume and reduction volume are made according to these models.The calculation results reveal that between 1993 and 2010,the CO 2 emission volume reached 31.069 Gt,reduced by 0.439 Gt,averaging 28.83 Mt each year.
文摘Due to ongoing growth in carbon emission, many governments＇ have taken measures to curb it. Thus, it is of great importance to measure carbon emissions in international trade and probe into the causes behind them. This paper first applies inputoutput model then it estimates the carbon emissions embodied in China＇s international trade in 2002, 2005 and 2007. Using structural decomposition analysis, this paper measures carbon emissions in international trade by their scale effect, composition effect and intensity effect. Our results illustrate： （1） a rapidly-rising net export of carbon emissions for China, and （2） scale effect and composition effect stimulates carbon emissions embodied in exports, while intensity effect discourages it.
基金Funded by Regional Transportation Integration Technology of FAFU (No.Pytd 12006)Science and Technology project of Fujian Education Department (No.JB 11046)
文摘Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a formula that was applicable to carbon-emission calculation, and discussed carbon-emission characteristics of concrete structures and steel construction.Owing to the difference of electrical and mechanical equipment used in construction phase, the results show that under the same conditions, the carbon emission intensity of a concrete structure building is much higher than that of a steel building.At last, we also put forward some emission reduction measures based on the calculation data of different buildings.
文摘The objective of this research is to quantify the EEC （embodied energy/CO2） of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building＇s life-cycle, such as construction （including manufacture of materials and equipment）, renewal （including repair work） and demolition. Energy and CO2 emission intensities in terms of 401 sectors were calculated, using the 2005 I-O （input-output） table in Japan. According to our case study conducted from the construction phase to demolition, the EC （embodied CO2） of an office building used for 60 years is 12,044 t-CO2 and 1,093 kg-CO2/m^2 in total. CO2 equivalent emissions （CO2e） by Freon gases, contained in building materials, equipment and devices, were also calculated. As the results, CO2e by insulators was 2% of the building＇s EC and CO2e by refrigerants was 9%-12% of the building＇s EC. It is important to keep reducing emissions of Freon gases contained in refrigerators.
文摘The study on greenhouse gas inventory in urban China lags far behind the global level. The important factor that curbs the carbon inventory of cities of China is inventory methodology and scope. Given the insufficiency of Chinese cities carbon inventory, a system and accounting model （scopel＋ scope2） as well as principles and boundaries were proposed for China. The carbon emissions in scopel and scopel＋ scope2 were calculated in Chinese prefecture-level cities. The EDGAR dataset was used for the calculation of scopel carbon emissions in cities in China and the level of uncertainty was analyzed as well. The results showed that the direct carbon emission of cities in China was about 31.65% of China total emissions. The scopel＋ scope2 carbon emissions in cities of China were calculated based on the GIS and RS model. The results showed that the sum of direct （scopel） and indirect （scope2） carbon emissions of cities in China accounted for 38.80% of total China carbon emissions.
文摘We evaluate economic and environmental impacts of climate change mitigation in a country scale considering various time horizons in the analysis applying a single-country dynamic computable general equilibrium model with endogenous technological change. Although there is a possibility that Gross Domestic Product （GDP） becomes larger for the abatement cases than the baseline case in the earlier years, it tends to be lower than that in the later years. The longer the time horizon and/or the more severe the abatement, the larger the negative impacts will be. When subsidizing R＆D investment, increase in GDP compared to the baseline case is realized in the middle of the time horizon, and the larger increase tends to be observed for the longer-term cases. These results would be due to technological change induced by the subsidies and emission abatement. Environmental indicators are also improved. We showed that the results were influenced by the target time horizon when using an intertemporal dynamic model.
基金supported by Science and Technology Program of the Ministry of Housing and Urban-Rural Development[2022-S-031]CSCEC1B Technical and Development Plan[Grant No.CSCEC1B-2021-33].
文摘The determination of carbon emission from foundation pit engineering is a tough and complex project owing to its characteristics including large material consumption,short use time,difficult recycling and no operation stage.To overcome these limitations,the calculation boundary and calculation method for carbon emission of foundation pit project are defined in this paper,which is successfully applied in the carbon emission analysis of the actual engineering project,i.e.the construction of large-scale foundation pit of Kunming comprehensive transportation international hub.All the carbon emissions coresponding to four working stages including building materials production,building materials transportation,construction and demolition were calculated and anatomized.The results revealed that the content of CO_(2) released in the stage of building materials production accounts for 89.3%of the total carbon emission,which means the amount of building materials consumed in the engineering project is the crucial factor to control the carbon emission.Besides,two kinds of carbon reduction measures,i.e.optimization design of support scheme and recycling waste materials of internal support demolition,were explored by analyzing the proportion and average value of carbon emission from different sub project of the support structure.A pronounced effect of carbon reduction was achieved.Furthermore,both a fast calculation method of carbon emission factor of unit work volume and general carbon reduction measures are proposed in this paper,which could provide a reference and new viewpoint for the engineers and designers to calculate and analyze the carbon emission and to take effective carbon reduction measures.
