Sunrain Group, a global low-carbon clean energy integrated service provider with core competencies in air-source heat pump and solar energy technologies. Established in 1999, Sunrain has been dedicated to the efficient collection, storage, and utilization of renewable energy. Through "PV-ESS-heat pump" intelligent multi-energy system coupling, which delivers electricity, heating, and hot water supply, offering comprehensive, one-stop clean energy innovation solutions for diverse client scenarios. The company was awarded the Second Prize of the National Science and Technology Progress Award for its innovative application of ultra-low temperature heat pumps, high-efficiency large flat-plate solar collectors, along with system integration and smart operation & maintenance (O&M) technologies in buildings located in extreme cold regions.