Pollution from coal-fired power plants is responsible for more than 100,000 deaths per year, whereas the crisis at the Fukushima nuclear plant is unlikely to kill a single person

People are getting nervous about nuclear power in the wake of the problems at the Fukushima nuclear power plant in Japan, questioning whether nuclear power is a sensible option for energy production in light of the perceived risks.

It has been three weeks since the earthquake and tsunami in Japan. There have been problems at the Fukushima plant with cooling, gas explosions (not nuclear), and radiation leaks – all serious issues, but so far no one has died. The earthquake and tsunami have killed more than 10,000 people.

In fact, the disaster shows how safe nuclear reactors actually are. Reactors designed half a century ago survived an earthquake many times stronger than they were designed to withstand, immediately going into shut-down (bringing driven nuclear reactions to a halt). But the radioactive products in the reactor keep decaying, producing heat, so they must be cooled.

The real problems began when the tsunami took out all the back-up generators that were meant to provide power to circulate the coolant. Loss of site power is the worst-case scenario for a nuclear power plant, so for Fukushima this was the worst crisis imaginable. New reactors have improved safety features, including passive systems that allow cooling to take place without power.

Radiation leaks are undoubtedly serious. But it is worth remembering that we are subjected to background radiation every day as a result of natural processes – some people more than others. Those living in UK areas with a lot of granite rocks, such as Cornwall, will have higher exposure than those who live somewhere like the Thames Valley. People who take flights expose themselves to radiation from cosmic rays, and airline pilots flying high-altitude routes can receive doses that put them in the top 5% of all workers in terms of radiation exposure.

People routinely and willingly expose themselves to large amounts of radiation for medical checks, with dental x-rays providing perhaps the highest doses, often for purely cosmetic reasons.

Safety limits for nuclear facilities are necessarily stringent and contamination is taken extremely seriously. However, these precautionary limits can cause unnecessary alarm. For example, there were recommendations for restrictions on drinking water, which have now been lifted, but the radiation dose received by drinking Tokyo water for a year would have been less than that from moving to Cornwall and living there for a year.

So far the releases from Fukushima have been relatively low, but continual monitoring is essential. Calls to widen the exclusion zone or to evacuate must be weighed against the risks of evacuation, which itself leads to many deaths, especially among the old and infirm. Also of concern is the breach of containment leading to the contamination of cooling water, and the reports of radioactive material leaking into the sea. While very serious, it is fortunate that the worst effects are contained on the site and that anything that flows into the ocean – either by accident or to relieve storage problems on land – will be greatly diluted.

Clearly we should learn from the mistakes that have been made during the crisis. However, we should remember that Japan has few natural energy resources, so nuclear power is important for its self-sufficiency. The country has been generating nuclear power for 45 years and currently produces almost 30% of its electricity this way.

Is it reasonable to decry nuclear power because of a crisis that has killed no one, caused by a natural disaster that killed thousands?

Compared with other sources of energy, nuclear power is one of the safest. We worry about radiation but are happy to accept air pollution from fossil fuels. Coal-related air pollution from power plants is globally responsible for more than 100,000 deaths per year.1,2 The World Health Organisation estimates that indoor air pollution from biomass and coal causes 1.5m premature deaths per year.3

Coal mining accidents also kill thousands every year, but are seldom reported.

I do not wish to trivialise the problems at Fukushima. I dislike the radioactive waste and safety issues of nuclear fission as much as anyone, which is why I work in research into a new form of nuclear energy – fusion. It's the energy source that powers the sun and has none of the downsides of fission.

Fusion will produce abundant energy cleanly and safely, but it is not yet ready. With continued political and financial support we hope to have fusion power stations by the 2050s.

However, I believe we cannot sideline nuclear fission because of Fukushima. We are in a critical situation. The threat of climate change is much greater than the threat of radiation, but no one is scared of carbon dioxide.

Millions of people in the developing world still live in poverty, which access to energy can alleviate. Global energy demand will continue to rise, so energy will continue to get more expensive as fossil fuels become more and more difficult to extract.

The use of renewables is increasing and will play an important part in the future energy mix, but it's questionable whether renewables alone will be able to satisfy rising energy demands. Technical advances in storage, transportation and efficiency are still required.

In the meantime, if we want to provide sufficient carbon-free energy we will have to use nuclear fission. I don't think this is incompatible with an environmentalist attitude. People working in nuclear power often care deeply about the environment and the energy problem. Despite some obvious downsides, they see nuclear power as the best solution.

Sitting back and doing nothing, or – worse still – cutting off possibilities, is not an option.

Dr Melanie Windridge is a freelance science communicator and academic visitor in nuclear fusion research at Imperial College London

References

1. IEA Key World Energy Statistics 2010

2. Power Generation and the Environment – a UK Perspective, vol 1, European Commission DGXII

3. International Energy Agency, World Energy Outlook: Implication of Energy Poverty on Health and Environment