Using Solar Hot Water to Address Piping Heat Losses in Multifamily Buildings

Springer, David¹  Seitzler, Matt¹  Backman, Christine¹  Weitzel, Elizabeth¹ 

[1] National Renewable Energy Lab. (NREL), Golden, CO (United States)

关键词: residential;    Residential Buildings;    ARBI;    Building America;    TRNSYS;    multifamily;    domestic hot water;    solar water heater;    recirculation;   

DOI  :  10.2172/1225932
RP-ID  :  NREL/SR--5500-64662
RP-ID  :  DOE/GO--102015-4716
PID  :  OSTI ID: 1225932

学科分类：能源（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

Solar thermal water heating is most cost effective when applied to multifamily buildings and some states offer incentives or other inducements to install them. However, typical solar water heating designs do not allow the solar generated heat to be applied to recirculation losses, only to reduce the amount of gas or electric energy needed for hot water that is delivered to the fixtures. For good reasons, hot water that is recirculated through the building is returned to the water heater, not to the solar storage tank. The project described in this report investigated the effectiveness of using automatic valves to divert water that is normally returned through the recirculation piping to the gas or electric water heater instead to the solar storage tank. The valves can be controlled so that the flow is only diverted when the returning water is cooler than the water in the solar storage tank.