Nuclear debate must keep up with changing reactor technology

Across the world, the contentious debate over the future of nuclear power continues apace. In East Asia, for instance, it emerged earlier this month that a nuclear plant in Taiwan may have been leaking radioactive water for three years. Meanwhile, Japan is still struggling to contain radioactive water from Fukushima; and, in South Korea, prosecutors are conducting a huge investigation into forged nuclear safety certificates.

The old controversies over nuclear reactors - their dangers, benefits and costs - remain at the fore. But as politicians, energy experts and the general public weigh the pros and cons, one key element in harnessing energy from the atom is being neglected.

That is, the link between the different methods of producing nuclear power and the nature - and longevity - of the radioactive waste that each method leaves behind. This in turn raises the issue of intergenerational justice: the technical choices we make today will determine the extent of the burden humanity will face in containing contaminated by-products that can remain radioactive for thousands of years.

While an increasing number of states are being swayed by the fact that nuclear power can enhance domestic energy security, produce large amounts of energy, and emit very low greenhouse gas by-products, critics nonetheless remain vociferous. They cite the risk of reactor accidents, the dangers of transporting nuclear fuel and fears of proliferation, and the vexing problem of how to deal with the long-lived nuclear waste.

However, little is said about the major distinctions between the various production methods, or nuclear fuel cycles. Rather than reducing nuclear power to a simple yes/no, good/bad dichotomy, we need to focus first on the advantages and disadvantages of each nuclear energy production method, including the burdens and benefits they pose now and in generations to come.

One of the key differentiating features between the various production methods is the nature of waste produced after irradiating fuel in a reactor. In the so-called open fuel cycle (common in the US and Sweden, for example) spent fuel is generally disposed of as waste that will remain radioactive for 200,000 years.

In the alternative, known as the closed fuel cycle, spent fuel is reprocessed to extract the redeployable uranium and plutonium, which are then re-entered into the fuel cycle. In the closed fuel cycle, the lifetime of radioactive waste is reduced to about 10,000 years.