Mugunghwa on the Water, Giant Battery in the Mountains... Korea Hydro & Nuclear Power's New Energy Experiment [Report]

47.2MW Imha Dam Floating Solar Power Embracing the Taegeukgi and Mugunghwa
A "Cooperative Renewable Energy Model" with 4,000 Local Residents Participating
A Massive Water Battery 720 Meters Underground in the Mountains of Yecheon
Pumped-Sto

As you travel along the mountain roads in the northeastern part of Gyeongbuk Province, you encounter two completely different power generation landscapes. On the surface of Imha Dam in Andong, a gigantic Taegeukgi and Mugunghwa, illuminated by sunlight, float on the water. Deep within the mountains of Yecheon, massive generators powered by water quietly help sustain the power grid. Although Korea Hydro & Nuclear Power is widely known as a nuclear power company, it actually underpins the entire national grid by also embracing solar and pumped storage power generation.

On May 15, at the floating solar power complex on Imha Dam in Andong, Gyeongbuk, deep blue solar modules formed a massive pattern on the lake that appeared at the end of a winding mountain road. Viewed up close, the facility resembled more a monumental installation artwork than a conventional power plant. The floating solar modules were arranged in the shapes of the Taegeukgi flag and the Mugunghwa flower, combining the symbolism of Korea with an eco-friendly energy facility.

The Imha Dam floating solar power facility is the largest of its kind in Korea, with a total capacity of 47.2 MW. It was built across a 520,000-square-meter water surface spanning the Imhamyeon and Imdong-myeon areas of Andong City, and generates approximately 61,000 MWh of electricity annually—enough to supply about 20,000 households.

The largest floating solar power facility in South Korea, located on the surface of Imha Dam in Andong City, Gyeongbuk Province. Solar modules arranged in the shapes of the Taegeukgi flag and the Mugunghwa flower spread over the water. Korea Hydro & Nuclear Power.

Unlike land-based solar power, floating solar power causes almost no damage to mountainous terrain. Thanks to the cooling effect of the water surface, it is also relatively more efficient. In particular, the Imha Dam project stands out for its use of the existing hydropower transmission network. During the day, solar power is transmitted; at night, hydropower is sent through the same network—an “alternate generation” structure. Compared to other renewable energy projects nationwide that have stalled due to a lack of transmission infrastructure, this is a highly efficient model.

Another feature of this power plant is community participation. Led by Gyeongsangbuk-do Province and Andong City, and jointly implemented by Korea Hydro & Nuclear Power and Korea Water Resources Corporation, it is the nation’s first resident-participatory renewable energy cluster. More than 4,000 residents from 33 villages within a 1-kilometer radius participated as investors. Over the next 20 years, profits distributed to local residents are expected to total about 22.2 billion won. Thus, the power plant serves not only as an electricity generation facility but also as a local profit-sharing model.

The scene at Yecheon Pumped Storage Power Plant, visited the same day, was entirely different. Water originating from the upper dam near the mountaintop travels down to a power station deep underground. After descending a long tunnel by bus, two enormous generators came into view. The mechanical sounds in the damp, cold air evoked the atmosphere of a massive submarine interior.

Pumped storage works by using surplus electricity to pump water upwards, then releasing it to generate electricity when needed. Essentially, it stores electricity in the form of water’s potential energy.

Yecheon Pumped Storage Power Plant, completed in 2011, is Korea’s newest pumped storage station, equipped with two 400 MW generators for a total capacity of 800 MW. This accounts for about 12% of the country’s total pumped storage capacity.

A panoramic view of the upper dam at Yecheon Pumped Storage Power Plant in Gyeongbuk. During times of excess electricity, water from the lower dam is pumped up and stored, and when electricity demand surges, water is released to generate electricity, functioning as a 'giant water battery.' Korea Hydro & Nuclear Power.

Recently, the role of pumped storage has become increasingly critical as the proportion of renewable energy sources such as solar and wind has grown, leading to greater variability in electricity production. Power grids must always maintain a constant frequency, and pumped storage can adjust output within minutes, thereby stabilizing the system.

A site official explained, "The pumped storage power plant is the safest and largest high-capacity battery. It acts like an emergency rescue team, being the first to respond when there are sudden fluctuations in electricity supply and demand."

In fact, during a blackout situation, pumped storage is the first power source to be activated. Electricity generated from the upper dam is used to restart other large power plants, serving as the “starter power.” While nuclear plants reliably supply base load power, pumped storage helps stabilize the grid whenever its balance is shaken.

Korea Hydro & Nuclear Power currently operates not only nuclear plants but also seven pumped storage power plants nationwide, with a total of 16 pumped storage units and a capacity of 4,700 MW. The company is also pursuing new pumped storage projects in Yeongdong, Hongcheon, and Pocheon.

Beyond its reputation as a nuclear energy firm, Korea Hydro & Nuclear Power has already evolved into a comprehensive energy company, spanning hydropower, solar, and pumped storage. The floating solar project on the water in Andong and the pumped water battery in the mountains of Yecheon exemplify this transformation.

This content was produced with the assistance of AI translation services.