The renewable energy will play significant role in the world primary energy consumption in the future. Geothermal energy is immense with 5 000 EJ/a of technical potential, and geothermal heat pumps (GHPs) are one of t...The renewable energy will play significant role in the world primary energy consumption in the future. Geothermal energy is immense with 5 000 EJ/a of technical potential, and geothermal heat pumps (GHPs) are one of the fastest growing applications of renewable energy in the world with annual increases of 10 % and much faster in China. With high coefficient of performance (COP) up to 6, GHPs make efficiency of primary energy more than 240 % with assumed a 40 % of electricity generation efficiency, which means energy savings and CO2 emission reduction. In this paper,the geothermal resources and its utilization are talked about, and GHPs technology was introduced. Due to its high efficiency, there will be energy savings by using GHPs. There is also CO2 emission reduction because of using geothermal heat pumps, which is analyzed in the end.展开更多
The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bo...The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bored 368 m deep underground.Carbon dioxide(CO_(2))is used as working fluid.In the TPCT there is no condensation section.CO_(2)is condensed by the evaporator pf the heat pump,flows into the head of the TPCT and nuns down as a falling film along the inner wall of the pipe.For the heat transfer simulation in the TPCT,a quasi-dynamic model in which the mass transfer between the liquid and vapor phases as well as the conduction heat transfer from the surrounding soil towards the pipe is treated dynamically.However the film flow modeling is based on the Nusselt theory of frilm condenssation.The compauison of the experimental data with the numerical simulation is presented and discussed.展开更多
INTRODUCTION Community Housing Partners(CHP)is a 501(c)(3)community development corporation that serves the needs of low-income and low-wealth individuals and families in the southeast.CHP’s mission is to create affo...INTRODUCTION Community Housing Partners(CHP)is a 501(c)(3)community development corporation that serves the needs of low-income and low-wealth individuals and families in the southeast.CHP’s mission is to create affordable,green,sustainable housing opportunities and services for the people and communities they serve.Since 1975,CHP has served over 206,000 people,including the elderly,women and children in transition,formerly homeless people,single female heads-of-household.展开更多
文摘The renewable energy will play significant role in the world primary energy consumption in the future. Geothermal energy is immense with 5 000 EJ/a of technical potential, and geothermal heat pumps (GHPs) are one of the fastest growing applications of renewable energy in the world with annual increases of 10 % and much faster in China. With high coefficient of performance (COP) up to 6, GHPs make efficiency of primary energy more than 240 % with assumed a 40 % of electricity generation efficiency, which means energy savings and CO2 emission reduction. In this paper,the geothermal resources and its utilization are talked about, and GHPs technology was introduced. Due to its high efficiency, there will be energy savings by using GHPs. There is also CO2 emission reduction because of using geothermal heat pumps, which is analyzed in the end.
基金The present research work was supported by the Federal Ministry for Economic Affairs and Energy of Germanyunder the funding code FKZ:03ET1050B.
文摘The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bored 368 m deep underground.Carbon dioxide(CO_(2))is used as working fluid.In the TPCT there is no condensation section.CO_(2)is condensed by the evaporator pf the heat pump,flows into the head of the TPCT and nuns down as a falling film along the inner wall of the pipe.For the heat transfer simulation in the TPCT,a quasi-dynamic model in which the mass transfer between the liquid and vapor phases as well as the conduction heat transfer from the surrounding soil towards the pipe is treated dynamically.However the film flow modeling is based on the Nusselt theory of frilm condenssation.The compauison of the experimental data with the numerical simulation is presented and discussed.
文摘INTRODUCTION Community Housing Partners(CHP)is a 501(c)(3)community development corporation that serves the needs of low-income and low-wealth individuals and families in the southeast.CHP’s mission is to create affordable,green,sustainable housing opportunities and services for the people and communities they serve.Since 1975,CHP has served over 206,000 people,including the elderly,women and children in transition,formerly homeless people,single female heads-of-household.
