11:00 AM - 1:00 PM
[AHW27-P06] Demonstration of the ground-source heat-pump system in Saitama
-Report of the latest cooling operation test-
Keywords:groundwater heat, ground-source heat-pump system, Kanto plain
Geothermal energy systems are a type of renewable energy system. They are superior in energy efficiency and are spreading in Japan and overseas. The ground-source heat-pump (GHP) system is widely used for room heating and cooling and hot water supply in large facilities and housings. It is important to quantitatively compare the operating efficiency, cost, and environmental effects of GHP and air source heat pumps (AHP) through experiments to promote the use of GHP in the future. The operating efficiency of both heat pumps varies with the weather conditions and heat loads at the installation sites and only the efficiency of GHP varies with the subsurface environmental conditions.
In 2018, the Local Government of Saitama Prefecture installed both GHP and AHP in five small-scale buildings in the prefecture. Among the five sites, four sites (Hanyu site, Miyashiro site, Kasukabe site, and Hanno site) contain atmosphere-monitoring stations and the fifth site (Kazo site) is the Eco-Lodge of the Center for Environmental Science in Saitama. At the atmosphere-monitoring stations in four sites where the demonstration experiments were conducted, the continuous cooling and heating operation tests were conducted for examination of the operation efficiency of the GHP and AHP. These systems operated from April 2018 to October 2021.
The final operational demonstration was the cooling operation test in August 2021, and the results are presented in this presentation. In the previous operation tests in the summer of 2019 and the summer of 2020, the GHP and AHP were operated alternately for 10 days or 15 days, but operation test in the summer of 2021, the performance was compared by comparatively long term operation (1 month) focusing on the GHP.
As a result of the test, good data (inlet/outlet temperature and circulating fluid flow rate) were obtained at three atmosphere-monitoring stations (Hanyu site, Kasukabe site and Hanno site). On the other hand, at the atmosphere-monitoring station (Miyashiro site), an abnormality occurred in the temperature sensor of the secondary circulation system, which seemed to be caused by age-related deterioration. The average SCOPs (preliminary data) were obtained were 5.5 for Hanyu site, 5.4 for Kasukabe site and 4.8 for Hanno site. These results are consistent with the results of the cooling operation tests in the summer of 2019 and the summer of 2020. It is significant that the reproducibility of the results and the operation performance over a relatively long period of time were confirmed.
Acknowledgment: We express our gratitude to Prof. Masakatsu Sasada (the president of the Geo-Heat Promotion Association of Japan) for his advice during the research. The experimental systems were constructed by PEC Corporation, Agricluster Corporation, Home Enesys Corporation, and Corona Corporation. Oyo Corporation cooperated in the data collection and the analysis.Besides, the demonstration experiment was conducted based on the knowledge from the Grants-in-Aid for Scientific Research, 19K12436, 19K12364, and 19K12365.
In 2018, the Local Government of Saitama Prefecture installed both GHP and AHP in five small-scale buildings in the prefecture. Among the five sites, four sites (Hanyu site, Miyashiro site, Kasukabe site, and Hanno site) contain atmosphere-monitoring stations and the fifth site (Kazo site) is the Eco-Lodge of the Center for Environmental Science in Saitama. At the atmosphere-monitoring stations in four sites where the demonstration experiments were conducted, the continuous cooling and heating operation tests were conducted for examination of the operation efficiency of the GHP and AHP. These systems operated from April 2018 to October 2021.
The final operational demonstration was the cooling operation test in August 2021, and the results are presented in this presentation. In the previous operation tests in the summer of 2019 and the summer of 2020, the GHP and AHP were operated alternately for 10 days or 15 days, but operation test in the summer of 2021, the performance was compared by comparatively long term operation (1 month) focusing on the GHP.
As a result of the test, good data (inlet/outlet temperature and circulating fluid flow rate) were obtained at three atmosphere-monitoring stations (Hanyu site, Kasukabe site and Hanno site). On the other hand, at the atmosphere-monitoring station (Miyashiro site), an abnormality occurred in the temperature sensor of the secondary circulation system, which seemed to be caused by age-related deterioration. The average SCOPs (preliminary data) were obtained were 5.5 for Hanyu site, 5.4 for Kasukabe site and 4.8 for Hanno site. These results are consistent with the results of the cooling operation tests in the summer of 2019 and the summer of 2020. It is significant that the reproducibility of the results and the operation performance over a relatively long period of time were confirmed.
Acknowledgment: We express our gratitude to Prof. Masakatsu Sasada (the president of the Geo-Heat Promotion Association of Japan) for his advice during the research. The experimental systems were constructed by PEC Corporation, Agricluster Corporation, Home Enesys Corporation, and Corona Corporation. Oyo Corporation cooperated in the data collection and the analysis.Besides, the demonstration experiment was conducted based on the knowledge from the Grants-in-Aid for Scientific Research, 19K12436, 19K12364, and 19K12365.