Geothermal energy offers effective heating, cooling: GGK CEO

GGK Co. Chief Executive Officer Ahn Geun-mook

Geothermal energy is an ideal energy source for South Korea, where the underground temperature is consistently stable regardless of the season and the occurrence of earthquakes is low, according to GGK Co. Chief Executive Officer Ahn Geun-mook. GGK is a small and mid-sized company specializing in geothermal heating technology.

During a recent visit to GGK’s office in Pangyo, Seongnam, Gyeonggi Province, Maeil Business Newspaper learnt that the office was heated and cooled using geothermal energy.

Although the outside temperature was a relatively hot 28 degrees Celsius, the office was cool even without the use of air conditioning.

“We cool the air by using energy drawn from 300 meters underground via two underground heat exchangers installed outside the building and in the basement,” Ahn said.

GGK has secured exceptional technology in the geothermal heating and cooling systems field, which helps buildings with heating and cooling using geothermal energy.

In Korea, the underground temperature always remains between 15 and 20 degrees Celsius. The geothermal heating and cooling system use the relatively warm underground heat in winter and the cool underground heat in summer to control the building’s temperature.

The geothermal heating and cooling system consist of an underground heat exchanger, which involves drilling holes in the ground and inserting pipes via which heat-exchange liquids such as water or antifreeze circulate, and a heat pump installed above ground that is connected to the underground heat exchanger. The liquid inside the underground heat exchanger transfers the geothermal energy from deep underground to the ground heat pump for heating and cooling.

As large companies like Samsung Electronics Co. and LG Electronics Inc. manufacture the heat pumps, the quality is consistent, and maintenance or replacement is easy as they are above ground.

The underground heat exchangers that are underground, on the other hand, face different challenges. They need to be used for over 30 years, similar to the lifespan of a building, but it is impossible to inspect or refurbish them if problems occurred, often rendering expensive geothermal systems useless.

[Courtesy of GGK Co.]

GGK has developed a new method for geothermal heating and cooling systems that eliminates the PVC pipes, which are the most frequently damaged components of the underground heat exchanger. The system simplifies the circulation by allowing groundwater to mix with the heat-exchange water that goes back into the ground after passing through the heat pump.

Ahn noted that “90 percent of the defects in underground heat exchangers are due to deforms or damage to the PVC pipes that are inserted and installed hundreds of meters deep.”

“GGK’s system, which applies a new design that eliminates PVC pipes, improved heat exchange efficiency by more than 11 percent compared to the conventional open systems,” he said.

If a problem occurs with the underground heat exchanger, maintenance and repairs are also possible using simple methods such as opening the lid above ground to replace the internal circulation pump or remove foreign substances. This unique technology is exclusive to GGK.

“GGK’s system can be used for over 30 years, comparable to the lifespan of a building,” Ahn said. “Based on these strengths, GGK’s technology has been applied to or contracted for a total of 124 new public building projects since 2019 that are awaiting construction.”

The geothermal energy market is expected to grow rapidly from 2025 onwards. The Zero Energy Building Certification System will be implemented from January of that year, making the adoption of renewable energy mandatory for private buildings with a total floor area of over 1,000 square meters.

“The renewable energy facilities applicable to buildings currently include solar, geothermal, and fuel cells,” Ahn said. “Given the same investment, geothermal can produce more than three times the energy produced by solar energy and more than ten times that of fuel cells.”

He added that over 70 percent of the renewable energy facilities chosen by public institutions constructing new office buildings are geothermal.

The Seoul Metropolitan Government recently announced that it would come up with a comprehensive plan to promote geothermal energy supply, which aims to supply 1 GW of geothermal facilities by 2030, or the equivalent to one nuclear power plant, which is a positive step.

“GGK’s sales target for 2024 is 15 billion won, with a new contract target of 25 billion won,” Ahn said. “Sales hit 6.3 billion won by the end of April, or 42 percent of the target, and new contracts totaled 12.2 billion won, or 48.8 percent, making it possible to exceed our goal for the year,” Ahn said.