Korea finalizes plans to ramp up pumped-storage hydroelectricity

Yangyang Pumped-storage power plant in Yangyang, Gangwon Province [Photo by Yonhap]

Korea Hydro & Nuclear Power Co. (KHNP) will invest 4 trillion won ($3.13 billion) to build a total of 1.8GW capacity pumped-storage power plants in three locations - Gyeonggi, Gangwon, and North Chungcheong Provinces.

The move marks a significant resurgence in pumped-storage hydroelectricity in the country, coming 12 years after the last one was built in 2011.

The initiative aims to address the issues of power grid instability arising from the increasing proportion of renewable energy sources, such as solar power, and to meet the potential unsatisfied power demand that could result from transitioning towards a nuclear-centric energy strategy.

Maeil Business Newspaper has learned Thursday that KHNP finalized the investment plan for the construction of the three pumped-storage power plants with a total capacity of 1.8GW in Pocheon, Gyeonggi Province, Hongcheon in Gangwon Province, and Yeongdong in North Chungcheong Province at the end of last month.

The total project cost is estimated to be 4.3 trillion won, which includes expenses for land compensation, plant construction, and procurement of equipment.

KHNP’s decision to pursue additional pumped-storage construction is driven by the need to complement the drawbacks of nuclear and renewable energy in the country’s journey towards achieving carbon neutrality.

Pumped-storage power plants function by utilizing inexpensive electricity usually during the night to pump water from a lower reservoir to an upper reservoir.

When electricity demand increases, water from the upper reservoir is released back to the lower reservoir through turbines and generates electricity.

One significant advantage of this method is its ability to respond actively to sudden incidents in the power grid, as it can ramp up power production faster than other conventional power plants.

Given recent incidents of output restrictions on solar and wind power generation facilities in regions like Jeju Island and the western coastal areas, the importance of stable output regulation from pumped-storage power plants has gained attention.

The Ministry of Trade, Industry, and Energy previously revealed a plan to introduce 1.8GW pumped-storage facilities as part of its 9th Basic Plan for Electricity Supply.

Moreover, the formulation of the 10th plan highlighted last year the necessity of up to 45 trillion won in investments, which include the construction of storage facilities (20.85GW) and pumped-storage power plants (1.75GW), to address the volatility of renewable energy and provide backup facilities.

“An investment of 45 trillion won is required for securing backup facilities to cope with renewable energy fluctuations, but pumped-storage capacity can help reduce this cost,” said Seoul National University of Science and Technology Professor Yoo Seung-hoon.