Is nuclear power truly green? How do we solve decommissioning and waste issues?

Nuclear power is efficient and environmentally friendly, but decommissioning costs and nuclear waste disposal are significant challenges. This article analyzes the economics and environmental impact of nuclear power, and discusses potential solutions in the form of fourth-generation reactors and fusion power.

 

Proponents of nuclear power argue that it is highly efficient, environmentally friendly, and relatively resource-rich. In fact, it is possible to generate the same amount of electricity with a small amount of uranium compared to the amount of fossil fuels used in thermal power generation. It takes about 7.5 times as much oil to generate the same amount of electricity as uranium. Also, the disadvantage of so-called “renewables” such as solar and wind power is that they generate little electricity, which is not the case with nuclear power, which can produce electricity in large quantities. On the other hand, they also produce very little environmental pollution compared to thermal power generation, which produces a lot of greenhouse gases such as carbon dioxide. These advantages are undeniable, and it’s safe to say that nuclear power plants are an essential part of modern society. Nevertheless, there are several reasons to oppose the expansion of nuclear power plants like the models currently in place.
First, it costs a lot of money to decommission a nuclear power plant. It costs about $158 million to build a nuclear power plant, but after 15 to 20 years of depreciation, it can make a lot of money. The problem is that decommissioning a nuclear plant is also expensive. For the 23 reactors currently in operation, the cost of decommissioning them is about $1.1 billion using KEPCO’s 2012 adjusted decommissioning costs, or about $2.37 billion to $3.16 billion using the International Atomic Energy Agency formula. Nuclear power plants are economical because of their low unit cost of electricity generation, but the cost of decommissioning them at the end of their life, more than 30 to 40 years after completion, is not ideal. Therefore, if nuclear power plants are expanded for economic reasons, the burden on future generations will increase in the decades to come.
On the other hand, there are strict conditions that must be met in order for a nuclear power plant to be built. As with hydropower, there are not many places that meet these conditions, and building a nuclear power plant will inevitably destroy the environment. The extent to which the environment will be disrupted cannot even be estimated before the site is surveyed, as it is only after the site is surveyed that the site will meet the conditions. By expanding nuclear power plants, we are accepting that nature will be further damaged. On the other hand, as mentioned above, nuclear power plants are astronomically expensive to demolish, so there is a difference between installing a nuclear power plant and installing another power plant, even if they use the same site. In the case of other power plants, the site can be used for reconstruction or replacement of parts even when the building is aging, but in the case of nuclear power plants, the main building is contaminated with radioactivity and requires a lot of money to rebuild, so there is a big difference in the actual period of use of the site. Therefore, the expansion of nuclear power plants should be approached with caution. As we will see later, nuclear fusion power, which is not the current third-generation nuclear power plant, is relatively less constrained by the site and can be used for a long time, and until it is developed, renewable energy and individual/corporate efforts can serve as an alternative to nuclear power. At the individual level, individuals can make efforts to conserve electricity, and companies can reduce their electricity consumption by efficiently adjusting their production processes and developing highly efficient products. Still, the growing demand for electricity can be met through renewable energy.
On the other hand, many people are concerned about the safety of nuclear power plants. Citing tragic precedents such as Chernobyl and Fukushima, anti-nuclear activists question the safety of nuclear power plants. The Korean nuclear industry has set high design standards and has already created a manual of safety measures. Since the Fukushima accident was caused by a disaster that exceeded design standards, the KEPRI is currently working on a manual for managing major accidents through simulations and experiments. However, we cannot assume that the probability of an accident is zero. In particular, in the event of a war with North Korea, one of the first targets would be nuclear power plants, and expanding nuclear power plants would make it harder to defend each one of them because the manpower would be dispersed and the number of cases would increase. Therefore, from a reliability point of view, expansion is not desirable.
Perhaps the most problematic issue, however, is the disposal of nuclear waste, specifically high-level waste. The current generation of nuclear power, the third generation, uses uranium as fuel to generate energy through nuclear fission. However, radioactive waste is generated from this process, which is categorized into low-, intermediate-, and high-level waste according to its half-life. Low-level waste, which has a short half-life, is usually buried after compression or incineration, while intermediate-level waste is usually cemented with concrete or asphalt and stored in a repository. However, high-level waste, also known as spent nuclear fuel, cannot be disposed of as easily as low- and intermediate-level waste. Currently, South Korea temporarily stores high-level waste in specially built repositories inside power plants. However, there is only so much storage space left. It is a logical conclusion that as more nuclear power plants are built, the amount of high-level waste will increase, making it even more difficult to dispose of.
Some might argue that pyroprocess technology is a complementary solution. If the U.S.-ROK Nuclear Agreement (an agreement between the governments of the Republic of Korea and the United States for cooperation on the civilian use of nuclear energy) is revised to allow for the reprocessing of spent nuclear fuel, pyroprocessing, which is currently being researched by PRIDE at the Korea Atomic Energy Research Institute, could be used to dramatically reduce the volume, heat, and radiological toxicity of spent nuclear fuel, and the separated nuclear material (plutonium) could be used in a fourth-generation reactor. However, there are two crucial problems with this alternative. One is a possible revision of the South Korea-U.S. nuclear agreement. The main reason the US does not allow reprocessing is that it can be used to develop nuclear weapons. Because of this, South Korea has said that it will use dry reprocessing using pyroprocessing, which it claims will produce impure plutonium and thus prevent proliferation. However, according to a joint report by seven U.S. nuclear laboratories in 2009, impure plutonium from pyroprocessing can be wet reprocessed to obtain pure plutonium, so it cannot be considered highly nonproliferation-proof. Therefore, there is no reason to be optimistic about the revision of the KORUS nuclear agreement. Another is the fourth-generation reactors, especially fast breeder reactors. The plutonium produced through pyroprocessing is to be used in fast breeder reactors using sodium, but many advanced countries, including the United States, France, and Japan, have stopped researching or operating fast breeder reactors, so even the realization of fast breeder reactors is skeptical.
Clearly, nuclear power is still indispensable due to its high efficiency. However, relying heavily on nuclear power is bound to have side effects, and in the case of third-generation nuclear reactors, the problems outlined above are not uncommon. However, a new model of reactor, the fourth-generation reactor, can overcome the disadvantages of high-level waste to some extent. Of particular interest to South Korea are liquid metal reactors and hydrogen production reactors. The former uses nuclear fuel repeatedly, increasing the utilization rate of nuclear fuel by 60 times. The latter is a model that can produce hydrogen as well as electricity, which also increases energy efficiency for the same amount of fuel. There are several other models of fourth-generation reactors, which allow for more energy to be produced for the amount of high-level waste produced, reducing concerns about nuclear waste. If fusion reactors, the ultimate energy source of the future, were developed, they would eliminate the problem altogether, as they would produce no high-level waste. The downside of the fourth-generation nuclear reactor or fusion reactor is that it has not yet been developed. However, it is expected to be developed within a few decades, with South Korea having set a roadmap to commercialize nuclear fusion in the 2040s, so rather than expanding the third-generation nuclear power plants, it is better to rely on people’s efforts and other alternatives, and to invest heavily in areas such as fourth-generation nuclear reactors and fusion power generation to solve the problem of spent nuclear fuel as soon as possible.