23 August 2017
Heat pump technology provides a significant potential for CO2 emissions reduction. Annex 41 revisits research and development work in different countries to examine technology improvements leading to successful heat pump experience in cold regions. The primary focus is on electrically driven air-to-air or air-to-water air-source heat pumps (ASHP), with air or hydronic heating systems, since these products suffer severe loss of heating capacity and efficiency at lower outdoor temperatures. Other heat pump technologies were also investigated, including ground-source heat pumps and solar-assisted heat pumps. The main technical objective is to identify solutions leading to ASHPs with heating SPF > 2.63 W/W, recognized as a renewable technology. The main outcome of this Annex is information-sharing on viable means to improve ASHP performance in cold climate locations – loosely defined for purposes of the Annex as locales with a significant number of hours having ambient temperatures < -7°C. Austria, Canada, Japan, and the US (OA) participated in the Annex, which officially began in July 2012.