Nuclear power, which is a zero-emission source, also has limited greenhouse gas (GHG) emissions at below 500 kilograms per megawatt hour each year.

Is renewable energy a viable alternative to coal and nuclear in South Korea? The simple answer is no. There are already no rivers in South Korea that flow to the ocean without passing through a hydropower station. Solar power is not feasible due to low levels of solar irradiance. And even if all South Korea’s wetlands were used for tidal power, all the terrestrial and marine natural parks were changed to wind farms and all buildings were covered by photovoltaic cells, the maximum electricity generation from renewables could not provide more than 30 per cent of total electricity consumed in 2010.

Since 2011 there have been a series of nuclear-related events that could change not only South Korea’s future nuclear policy, but also its environmental and economic sustainability. The Fukushima-Daiichi nuclear accident prompted aggressive anti-nuclear movements. This could have been a blow to South Korea’s nuclear industry, but there was practically no adverse impact.

A survey conducted a year after the accident found that about 90 per cent of respondents still understood the need for nuclear power and about 80 per cent agreed with maintaining or increasing the share of nuclear energy in South Korea. To safeguard public support for nuclear power, the government has spent US$1 billion on safety measures to improve technological systems, including higher seismic resistance design requirements that well exceed the strongest earthquake ever observed in South Korea.

But the South Korean government still decided to reduce the planned nuclear capacity share from 41 per cent to 29 per cent by 2035 after considering ‘public emotion’. This decision was not based on any scientific or economic reasoning and did not even match with the public consensus. Due to this decision, coal power capacity will increase by 85 per cent compared with 2012, while the current share of renewables will be maintained. This change does not align with the national climate change policy target of reducing GHG emissions by 30 per cent compared with ‘business as usual’ by 2035.

In fact, to reduce the electricity sector’s GHG emissions while maintaining cheap prices, the share of nuclear power capacity needs to increase by over 50 gigawatts — or more than 70 per cent of total electricity consumption — by 2035. Given the current construction trend of 1.4 gigawatts per year, this target is achievable. But financing the additional nuclear power plants would cost about $US55 billion.

Increasing the share of nuclear power could cause two additional problems: spent-fuel management and aged nuclear plants. By the end of 2014, overall accumulated spent-fuel in South Korea amounted to about 80 per cent of the total storage capacity. Between 2023 and 2029, 12 nuclear power plants with the capacity of 9.7 gigawatts will reach their expiration date.

At the end of April 2015, the US and South Korea signed a new US–South Korea Civil Nuclear Agreement. The details have not yet been fully revealed, but this agreement is regarded as the most important move so far in dealing with spent fuel in South Korea. Since South Korea imports all its nuclear fuel, pyro-processing — which is partly allowed by the agreement — would be the ideal approach for dealing with spent fuel while securing a stable nuclear fuel supply.

In the long term, new generation IV reactor technologies that will be available commercially before 2030 in South Korea could provide a technical solution for these issues. These technologies, coupled with full fuel recycling, can generate a huge amount of energy from spent fuel. The advanced reactors also have inherent passive safety features that do not require any external manipulation in the case of an emergency. But a delicate medium-term plan is also needed to extend the reactors’ lifespans. This plan should focus not only on technical issues but also on regaining public trust after widely publicised corruption scandals.

After the issue of forged evaluation documents was reported in 2012, installed service parts with fake certificates were re-evaluated and replaced, following an intense investigation. There is no simple, short-term answer to tackling the endemic transparency and corruption problems in South Korea. In the long term, a public body with fairness, like a nuclear safety commission, must be established to monitor nuclear power plants, alongside internal measures proposed and implemented by KHNP.

South Korea must embrace nuclear power for environmental and economic reasons. Contrary to the expectations of many ‘green’ organisations in Korea, a nuclear phase-out policy will not increase the share of renewables. Instead, it will increase coal power production to maintain the price of electricity, while abandoning the hope of a more sustainable future. The main issues surrounding nuclear power in South Korea are social and institutional problems, not technological issues. To ensure a sustainable future for South Korea, public trust must be regained and issues concerning the safe management of nuclear power plants must be resolved.

Sanghyun Hong received his PhD degree at the University of Adelaide.