Kobe Steel Ltd. and three major Japanese power companies, Chubu Electric Power Co., Tokyo Electric Power Co. and Kansai Electric Power Co., announced on February 9, 2010, that they have jointly developed a high-efficiency hot water heat pump (HEM-HR90). The HEM-HR90 is the first heat pump of its kind to achieve a same-time supply of hot water at 90 degrees Celsius and chilled water at 7 degrees Celsius. The system is capable of dramatically reducing both costs and environmental impact.
In food and electronics factories, hot water is circulated to clean up materials through a boiler and chilled water is circulated for air conditioning or cooling through a refrigeration equipment. Conventional heat pumps supplying hot and chilled water efficiently from a single piece of equipment have previously been limited to supplying hot water at 70 degrees Celsius when supplying chilled water at 7 degrees Celsius.
However, the HEM-HR90 is able to efficiently and simultaneously supply hot water at 70 to 90 degrees Celsius and chilled water at 5 to 30 degrees Celsius by utilizing a two-stage screw compressor, by adjusting the electric motor to operate at higher temperatures and by selecting an adequate refrigerant. The system can be adapted to a heating process that yields hot water at 70 to 90 degrees Celsius, for applications such as thermal sterilization and hot-water washing.
When compared to conventional heat pumps that combine a boiler and refrigeration equipment, the HEM-HR90 can reduce running costs and energy consumption by approximately 60 percent, and reduce carbon dioxide (CO2) emissions by 70 percent.