Heat Pump System Tested in Jeju for Heating, Cooling, and Hot Water

"The current hot water temperature is about 46.5 degrees Celsius," said a Samsung Electronics representative, pointing to a control panel installed on the wall in the basement of a single-family home in Jeju's Donam-dong on September 14. The panel displayed the flow and temperature of water circulating in the house, as well as the air conditioning status. Nearby were a 200-liter hot water tank and a thermal storage tank, with insulated pipes running along the ceiling and walls.

One outdoor heat pump unit outside the house manages cooling, underfloor heating, and hot water supply. In summer, it uses heat generated during cooling to warm water, while in winter, it extracts heat from the outside air to create heating water. This system operates without burning oil or gas, relying solely on electricity for heating, cooling, and hot water.

This home features Samsung's integrated heating and hot water heat pump, the Eco Heating System (EHS) All-in-One. The government supply program utilizes heat pump boilers that provide heating and hot water without cooling capabilities. Unlike electric heaters that generate heat directly, heat pumps draw heat from the outside air to warm heating water and hot water, allowing them to supply more thermal energy than the electricity consumed.

The housing supply program for heat pumps is gaining momentum. Since April, the government and Jeju have been promoting a "Heat Pump Supply Project" with a total budget of 34.4 billion won. By the end of the year, they plan to install air-source heat pumps in 2,460 homes in the Jeju area.

Eligible participants include single-family and multi-family homes equipped with solar power systems of 3 kW or more. The project will install heat pumps under 20 kW, thermal storage tanks, and virtual power plant (VPP) systems. Of the maximum project cost of 14 million won per household, 70% (9.8 million won) will be subsidized by the national and provincial governments, with residents contributing 4.2 million won.

Demand is high, with 2,507 households applying for the 1,042 spots available in the first half of the year. An additional 1,418 households will receive installations in the second half, completing the project by year-end.

Jeju's proactive approach to heat pump distribution aims to reduce fossil fuel use in heating while easing renewable energy output control. When solar and wind power generation exceeds electricity demand or grid capacity, heat pumps can be activated to heat water, which is then stored in thermal tanks for later use in heating or hot water. This effectively converts surplus electricity into thermal energy for storage.

By managing multiple households' heat pumps through VPP systems, energy usage can be increased when there is excess power and reduced during peak demand. The reduction in greenhouse gases achieved through heat pump installations is also being considered for recognition as a carbon credit revenue model.

However, challenges remain before nationwide expansion can occur. Currently, the program is limited to single-family and multi-family homes with solar power systems. The need for space to install hot water tanks, thermal storage tanks, and piping makes it difficult to apply in existing apartments. The winter performance and actual cost-saving effects, which vary based on the home's insulation level and external temperatures, also need to be verified.

Developing an electricity rate plan that encourages heat pump usage during renewable energy generation periods while lowering household costs is another challenge. Jeju is reviewing options for introducing a rate plan that reflects the characteristics of heat pumps.