Cooling Without the Worry: The Secret of Groundwater

[Anchor]

With temperatures soaring above 30°C (86°F), many people are likely worried about their air conditioning electricity bills. Recently, an increasing number of buildings are saving electricity and reducing carbon emissions by utilizing discarded groundwater.

In this installment of Signal, our year-long series examining climate change, reporter Seo Donggyun provides the details.

[Reporter]

This is a mixed-use complex in Gangdong-gu, Seoul.

As the summer heat sets in, the air conditioning is constantly running, but there is little concern about electricity costs.

The secret lies in groundwater.

Let us head down to the building's basement.

When the ground is excavated during construction, groundwater naturally springs up like this.

This is because water from nearby rivers and streams constantly seeps underground.

In most buildings, this water is pumped out and discarded—often incurring sewage fees—but this building pumps the water up and directs it to a heat pump located nearby.

Groundwater maintains a temperature of around 16°C (61°F) throughout all four seasons.

During the summer, the groundwater absorbs heat from the heat pump's refrigerant, which has been warmed by indoor cooling, keeping the refrigerant cool. Conversely, in the winter, it supplies heat that is warmer than the outside air to the heat pump, allowing for efficient heating.

This building has also applied a technology that returns the groundwater used for heating and cooling back into the ground, which helps prevent sinkholes caused by indiscriminate underground development.

Compared to conventional heating and cooling systems, the energy efficiency is also superior.

[Lee Young-il / Technical Committee Member, Korea Groundwater and Geothermal Energy Association: It is currently estimated to save about 50% compared to city gas and about 30% compared to standard electric air conditioners.]

Cases of using discarded groundwater for heat pumps are also increasing in private homes.

[Groundwater Heat Pump User: Since I have to heat and cool a large house, costs are a major concern. I can save more than 40% on electricity bills.]

Across the country, there are 13 billion tons of groundwater available for use as an energy source annually.

Experts predict that if just 10% of this is utilized for heating and cooling heat pumps, it could achieve 20% of the government's greenhouse gas reduction target for 2035.

The government is currently pushing to classify groundwater as a renewable energy source.

(Video coverage: Jo Chang-hyun, Park Jin-ho, Bae Moon-san | Video editing: Choi Hye-young | PD: Kim Do-gyun, Han Seung-ho | XR: Lee Jun-ho, Jeon Yu-geun)
※ Please note: This article was translated by AI and may contain errors.