The leading two candidates to replace presidential incumbent Moon Jae-in — Lee Jae-Myung from the ruling liberal Democratic Party and Yoon Seok-Yeol of the conservative opposition People Power Party — are running neck and neck in the polls. While both have pledged to honour the country's emissions targets, their proposed roadmaps to reach that goal stand far apart from one another, most notably on the use of nuclear plants.
South Korea has already reduced its nuclear generation capacity in recent years, as president Moon pushed for halting construction of new nuclear plants and shutting down existing units nearing the end of their working lives.
The 679MW Wolsong reactor 1 was retired early in June 2018, despite the fact the country's nuclear commission (NSSC) had previously cleared it to operate until 2020. Plans to build the 1.4GW Shin-Hanul reactor 3 and 4, along with the 1.5GW Cheon-Ji reactor 1 and 2, were also scrapped under Moon's administration.
Moon's nuclear phase-out policies have faced criticism as the president set ambitious renewable targets to reach 2050 carbon neutrality, while simultaneously phasing out coal burn. Nuclear and coal-fired power generation accounted for around 27pc and 37pc of South Korea's power mix in 2019-21, respectively. In contrast, renewable output was around 5pc of the total power generation during the same period.
Lee Jae-Myung: Nuclear reduction not phase-out
The Democratic Party's Lee has proposed policies that are mostly in line with goals set by Moon, although one notable shift is towards a reduction in nuclear capacity rather than a full nuclear phase-out.
Under Lee's announced policies, no new nuclear units would be built, but plants already in operation or under construction would be maintained. Lee also plans to review plans to build the Shin-Hanul reactors 3-4.
The change in tack probably comes in response to both a public backlash to the nuclear phase-out policy and Lee's earlier target date to reach carbon neutrality by 2040 rather than 2050. He aims to achieve a 40pc reduction in greenhouse gas emissions, compared with 2018 levels, already by 2030.
To reach this goal, the Democratic Party candidate has proposed bringing forward coal-fired plant closures, relying instead on other forms of generation to meet power demand, and introduce carbon taxes. He also plans to gather the dispersed energy governmental ministries under a new climate and energy ministry, and increase government investment to build an AI-based power transmission and distribution network nationwide to better enable trade of renewable energy.
Yoon Seok-Yeol: Revival of the nuclear industry
While People Power Party candidate Yoon Seok-Yeol has yet to announce any detailed climate and energy policies, he has pledged to put an end to Moon's nuclear phase-out plan.
The opposition candidate has not only pledged to resume construction of the 1.4GW Shin-Hanul reactors 3-4, but also revive South Korea's nuclear industry to strengthen exports of equipment, material and technology. That said, Yoon has not announced immediate plans to build new capacity, as he would first invest in developing new technologies aimed at extending the life span of nuclear reactors, including Small Modular Reactors (SMRs), as well as producing green hydrogen using nuclear energy.
The People Power Party candidate has pledged to slash the share of fossil-fuel output in the country's generation mix by a third, and fine-dust air pollution by more than 30pc, although details of such plans are scarce.
Yoon has criticised Moon for an increasing reliance on "expensive" gas-fired generation to enable his nuclear programme, resulting in state-owned Kepco's financial losses, and emphasised instead the role of nuclear energy in base-load power supply as coal-fired output is phased out. The candidate has pledged to maintain a level of nuclear output that would help to cut consumer energy costs in an effort to protect low-income families.