Korean geothermal heat pump system uses municipal water supply
Geothermal heat pump installation is now a booming market in Korea, with the number of installations approximately doubling every year.
Because the amount of groundwater used by residents and industry is up to 5 million cubic meters per day , researchers have begun to point towards this source as a means of producing a huge amount of thermal energy for heating and cooling buildings. Connecting heat pumps to the existing groundwater well head or municipal pipelines offer great potential for economical energy savings.
There are several pumping wells for municipal water along the Nakdong River, in southeastern Korea, utilizing a “bank infiltration” system to supply potable water to the city of Changwon. In a demonstration project, a small heat pump with a capacity of 52.8 kW was installed to supply heat and cooling to nearby office buildings. A bypass was made to the main water line from a well producing 2,000 cubic meters per day of drinking water. The temperature of the pumped water is about 18 degrees Celsius (about 64 degrees F) throughout the year. Flowrate to the heat pump was about 4 - 5.5 cubic meters per hour, depending on heating or cooling requirements.
The proof-of-concept system reported good results, with a maximum heat pump coefficient of performance (COP) of 5.7, while overall system COP was 4.1.