The nuclear solution

It is not money that makes the world go round, it’s energy. A nation’s wealth can be crudely measured by energy consumption. The US has five per cent of the world’s population, yet uses 25 per cent of the world’s energy. When we talk about energy, we think of oil and gas. But will it last forever?

Our current dependence on fossil energy is the biggest crisis humanity has faced. We burn oil to feed people; without nitrogen fixation by the Haber-Bosch process 40 per cent of the world’s population would starve, even if we all had an organically-grown vegetarian diet. Current consumption is 20 million fossil years per year. This is not sustainable.

Michael Crichton says, in his latest novel State of fear, that global warming is a myth, but we all know that releasing carbon contributes to the greenhouse effect. He says we shouldn’t waste our time on future energy solutions because some new technology will come along in time - it always has in the past.

Having seen how devastating nature can be in the recent tsunami, however, we must be concerned about climate change. Like Pinnochio’s nose, Crichton’s neck grows ever longer but at least that allows him to bury his head in the sand alongside the US government.

One hope for the future is the hydrogen economy but it still needs an energy source. What will we use to generate hydrogen? Can we develop cheap and efficient solar cells to capture energy from the sun? Or will wind and waves be a source of cheap clean power? Will nuclear power ever become acceptable again?

The problem is energy capture and generation. Biomass faces the same problems as fossil fuel, it captures the sun’s energy and releases it on burning carbonaceous matter - the problem of CO₂ emissions and global warming remains.

More chemists are needed to work on solar power. Many already are and there are a number of potential photovoltaic solutions that are chemical, for example dye-activated silicon, small-molecule organics and polymers. Nature’s light harvesting complexes are essentially supramolecular chemistry and we need to understand the biological processes of many-electron transfers, apply that to synthetic systems and make solar power cheaper and more efficient.

For the hydrogen economy, we also need efficient local power sources - the fuel cell in the home or automobile. There is also the long-standing issue of hydrogen distribution. Moreover, are there cheap devices with the same energy density as a tank of petrol and an internal combustion engine?

Nuclear energy is the bridging solution between a fossil powered past and a solar future. The French generate 80 per cent of their electricity from nuclear power, but are now running it down due to public pressure. However, world famous ecologist, James Lovelock, says that nuclear power is the most environmentally friendly option. It has zero emissions and a minimal waste problem. For example, a teraWatt hour of electricity yields 20 tonnes of nuclear waste as opposed to 10 million tonnes of CO₂ from fossil fuels. The one real fear with nuclear energy is the potential for terrorist intervention. To mitigate that we need better security and a means to localise any release.

Our current nuclear waste problem is a cold-war legacy. Modern nuclear power stations, optimised for power generation not bomb production, generate very little high level waste and are designed to fail-safe - unlike Chernobyl. Chemists have a lot to contribute to nuclear waste clean-up. There is, for example, enough iridium in Sellafield, UK, to more than pay for the whole site to be cleaned up.

When will the government wake up to these long term issues? Public opinion can change very quickly. How popular will nuclear power be when petrol is ?10 per litre or when the average domestic heating bill is bigger than the mortgage? More parochially, when will chemists wake up? Why isn’t this subject embedded in the undergraduate curriculum?

We have a bright future. In the long-term we will take power from the sun but in real-time and not from fossils. Before we get there we need to take advantage of the zero emission benefits of modern, clean nuclear power. Most importantly, however, we should start training a new cohort of nuclear scientists, by building new nuclear power plants now, while we still have the expertise.

Tony Ryan is professor of physical chemistry at the University of Sheffield, UK