The energy and environmental impacts resulting from the buildings sector are one of the impending problems which address the international action. The main strategies implemented to answer to this problem are the ener...The energy and environmental impacts resulting from the buildings sector are one of the impending problems which address the international action. The main strategies implemented to answer to this problem are the energy efficiency improvement, the CO2 emissions reduction and the renewable energy share increase in the energy mix. The key subject discussed in this paper is the ＂building energy impact＂, aimed to leading the building sector towards the energy efficiency improvement. The paper＇s aim is to show that an energy assessment is not able to give a consistent evaluation of building energy use, and it could be misleading. Therefore, the paper proposes the exergy assessment as complementary evaluation method, in order to achieve a complete description of the concept ＂building＇s energy impact on the environment＂. In the first section, we describe the parameters currently used for the building energy assessment, focusing on the primary energy index and the CO2 emissions index. In the second section, we introduce the exergy as a complementary index. This index is a possible answer to the problems previously identified. Finally, in the third section, we present three test-cases, analyzed through transient simulation software TRNSYS. The purpose of the test-cases analysis is to show the difference between energy and exergy assessment.展开更多
China achieved major progress in low-carbon development during the period of the 11th Five Year Plan (2006-2010). The increasing trend of energy intensity and carbon intensity of the economy as seen prior to 2005 was ...China achieved major progress in low-carbon development during the period of the 11th Five Year Plan (2006-2010). The increasing trend of energy intensity and carbon intensity of the economy as seen prior to 2005 was reversed to a sharp decreasing trend, leading to a 19% decrease in energy intensity and 21% decrease in carbon intensity in five years. The enhanced energy efficiency, mostly due to efficiency improvement in power and manufacturing sector, is the major driver of the decrease in carbon intensity of the economy. The development of renewable energy, despite its impressive growth rate, played a minor role because of its small share in the energy mix of the country. Energy con-sumption and energy-related carbon emissions per unit of area in building continued to grow at a lesser rate, which, combined with the fast growth of total building volume, led to fast growth in total energy consumption and carbon emissions in the sector. Similar trend is observed in the transportation sector whose total energy use and carbon emissions continued to grow fast despite slight improvement in energy efficiency. Agricultural energy use experienced a slight change and forestry made a major contribution to carbon sinks. Policy and institutional innovations helped build a solid system of rules for low-carbon development. Improving cost effectiveness of the system remains a major challenge for the next five year plan period.展开更多
Transport is a major component of energy consumption and 002 emissions in travelling. Understanding changes in the energy efficiency of tourism transport （EETT） and factors affecting this is important to the promoti...Transport is a major component of energy consumption and 002 emissions in travelling. Understanding changes in the energy efficiency of tourism transport （EETT） and factors affecting this is important to the promotion of low-carbon tourism. This paper established a new method following the top to bottom principle and analyzed EETT variation characteristics and influencing factors from 1994 to 2013 in China. We found that the energy consumption of tourism transport （ECTT） increased from 178.21 PJ in 1994 to 565.82 PJ in 2013 at an average annual growth rate of 6.27%; CO2 emissions of tourism transport （CETT） went up from 14.96×10^6t to 47.94×10^6 t due to person-trip and trip distance growth. EETT went from 3.22×10^6 person-trips PJ^-1 in 1994 to 5.99×10^6 person-trips PJ^-1 in 2013 at an average annual growth rate of 4.90%, and the CO2 emissions of tourism transport unit person-trips （CETTU） shifted from 26.07 kg person-trips^-1 in 1994 to 14.01 kg person-trips^-1 in 2013. Energy intensity decline, scale effects and policy promotion were key factors that enhanced EETT. Meanwhile, trip mode changes and enjoyment-oriented transport hindered EETT. Based on our analysis, we suggest methods to decrease ECTT and CETT. and enhance EETT.展开更多
China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provi...China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provides the most comprehensive COemission inventories of 287 Chinese cities from 2001 to2019.The emission inventories are compiled for 47 economic sectors and include energy-related emissions for 17 types of fossil fuels and process-related emissions from cement production.We further investigate the state of the emission peak in each city and reveal hidden driving forces.The results show that38 cities have proactively peaked their emissions for at least fve years and another 21 cities also have emission decline,but passively.The 38 proactively peaked cities achieved emission decline mainly by effciency improvements and structural changes in energy use,while the 21 passively emission declined cities reduced emissions at the cost of economic recession or population loss.We propose that those passively emission declined cities need to face up to the reasons that caused the emission to decline,and fully exploit the opportunities provided by industrial innovation and green investment brought by low-carbon targets to achieve economic recovery and carbon mitigation goals.Proactively peaked cities need to seek strategies to maintain the downward trend in emissions and avoid an emission rebound and thus provide successful models for cities with still growing emissions to achieve an emission peak.展开更多
文摘The energy and environmental impacts resulting from the buildings sector are one of the impending problems which address the international action. The main strategies implemented to answer to this problem are the energy efficiency improvement, the CO2 emissions reduction and the renewable energy share increase in the energy mix. The key subject discussed in this paper is the ＂building energy impact＂, aimed to leading the building sector towards the energy efficiency improvement. The paper＇s aim is to show that an energy assessment is not able to give a consistent evaluation of building energy use, and it could be misleading. Therefore, the paper proposes the exergy assessment as complementary evaluation method, in order to achieve a complete description of the concept ＂building＇s energy impact on the environment＂. In the first section, we describe the parameters currently used for the building energy assessment, focusing on the primary energy index and the CO2 emissions index. In the second section, we introduce the exergy as a complementary index. This index is a possible answer to the problems previously identified. Finally, in the third section, we present three test-cases, analyzed through transient simulation software TRNSYS. The purpose of the test-cases analysis is to show the difference between energy and exergy assessment.
基金Parts of the research funding comefrom International Climate Policy Initiative funded by the Soros Foundation
文摘China achieved major progress in low-carbon development during the period of the 11th Five Year Plan (2006-2010). The increasing trend of energy intensity and carbon intensity of the economy as seen prior to 2005 was reversed to a sharp decreasing trend, leading to a 19% decrease in energy intensity and 21% decrease in carbon intensity in five years. The enhanced energy efficiency, mostly due to efficiency improvement in power and manufacturing sector, is the major driver of the decrease in carbon intensity of the economy. The development of renewable energy, despite its impressive growth rate, played a minor role because of its small share in the energy mix of the country. Energy con-sumption and energy-related carbon emissions per unit of area in building continued to grow at a lesser rate, which, combined with the fast growth of total building volume, led to fast growth in total energy consumption and carbon emissions in the sector. Similar trend is observed in the transportation sector whose total energy use and carbon emissions continued to grow fast despite slight improvement in energy efficiency. Agricultural energy use experienced a slight change and forestry made a major contribution to carbon sinks. Policy and institutional innovations helped build a solid system of rules for low-carbon development. Improving cost effectiveness of the system remains a major challenge for the next five year plan period.
基金National Natural Science Foundation of China(41501159)Key Research of Hebei Education Department Foundation(SD151019)China Postdoctoral Science Foundation(2014M560731)
文摘Transport is a major component of energy consumption and 002 emissions in travelling. Understanding changes in the energy efficiency of tourism transport （EETT） and factors affecting this is important to the promotion of low-carbon tourism. This paper established a new method following the top to bottom principle and analyzed EETT variation characteristics and influencing factors from 1994 to 2013 in China. We found that the energy consumption of tourism transport （ECTT） increased from 178.21 PJ in 1994 to 565.82 PJ in 2013 at an average annual growth rate of 6.27%; CO2 emissions of tourism transport （CETT） went up from 14.96×10^6t to 47.94×10^6 t due to person-trip and trip distance growth. EETT went from 3.22×10^6 person-trips PJ^-1 in 1994 to 5.99×10^6 person-trips PJ^-1 in 2013 at an average annual growth rate of 4.90%, and the CO2 emissions of tourism transport unit person-trips （CETTU） shifted from 26.07 kg person-trips^-1 in 1994 to 14.01 kg person-trips^-1 in 2013. Energy intensity decline, scale effects and policy promotion were key factors that enhanced EETT. Meanwhile, trip mode changes and enjoyment-oriented transport hindered EETT. Based on our analysis, we suggest methods to decrease ECTT and CETT. and enhance EETT.
基金supported by the National Natural Science Foundation of China(72140001 and 41921005)Shandong Provincial Science Fund for Excellent Youth Scholars(ZR2021YQ27)+1 种基金the National Social Science Fund of China(21ZDA065)the Natural Environment Research Council(2021GRIP02COP-AQ)。
文摘China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provides the most comprehensive COemission inventories of 287 Chinese cities from 2001 to2019.The emission inventories are compiled for 47 economic sectors and include energy-related emissions for 17 types of fossil fuels and process-related emissions from cement production.We further investigate the state of the emission peak in each city and reveal hidden driving forces.The results show that38 cities have proactively peaked their emissions for at least fve years and another 21 cities also have emission decline,but passively.The 38 proactively peaked cities achieved emission decline mainly by effciency improvements and structural changes in energy use,while the 21 passively emission declined cities reduced emissions at the cost of economic recession or population loss.We propose that those passively emission declined cities need to face up to the reasons that caused the emission to decline,and fully exploit the opportunities provided by industrial innovation and green investment brought by low-carbon targets to achieve economic recovery and carbon mitigation goals.Proactively peaked cities need to seek strategies to maintain the downward trend in emissions and avoid an emission rebound and thus provide successful models for cities with still growing emissions to achieve an emission peak.
