Please welcome today’s poster, Chris, who is a lecturer at a university in Australia. Chris blogs at A Free Man.

I’ve been thinking a lot about energy lately. If you are reading this site, you are probably convinced that our current carbon-dependent system is unsustainable over the long run and that we need to come up with alternative energy sources. There has been a flurry of research in the last decade OR SO into sustainable energy. Research that has spurred frequent news stories about the next saviour of the planet – wind, solar, hydroelectric, ethanol, biodiesel. Switch grass. Remember switch grass? But as it stands, 86% of the world’s electricity still comes from fossil fuels.

This is because there is not yet a renewable energy source that can sate our gluttonous appetite for cheap energy. But there is a cleaner, and thus greener option. Unfortunately it isn’t very popular among those of us who care about the future of the planet.

I was listening to the Australian Broadcasting Corporation’s outstanding public affairs program ‘Counterpoint‘ the other day and the lead segment was an interview with Barry Brook, the director of the Research Institute for Climate Change and Sustainability at the University of Adelaide (Brook’s blog is here). Brook is a controversial fellow in the environmental community (such that it is) as he recognizes that the world’s power needs are going to continue to increase and the best way to match our species’ requirements is expansion of nuclear power.

Brook is not opposed to using renewable energy sources such as wind or solar, but can see the cold reality that they will not be “able to supply sufficient energy to power an industrial economy or indeed to allow the economy to grow.” Brook says that as we make the transition away from fossil fuels what we’re moving toward is an electrical society. If we are currently a 30% electrical society and we become, say, a 90-95% electrical society our demand for electrical power is going to triple. Brooks believes what a lot of us know in our hearts to be true – we’re going to need something more robust than windmills and solar panels.

Nuclear power fits that bill with the bonus that it is a relatively clean energy source. Nuclear power generation emits no greenhouse gasses and thus doesn not contribute to climate change. Nuclear power uses small amounts of a very concentrated power source rather than massive amounts of coal, oil or natural gas. Therefore, even though uranium is not a renewable resource, much less of the mineral is required to generate a large amount of power – less mining, less pollution. New technology, so-called “fast reactors,” burn up to 99% of nuclear fuel reducing the amount of waste generated and the waste that remains is “hot” for 300 years, rather than 100,000 years. This eliminates the primary problem with nuclear power – what to do with all that waste.

Most environmental groups are very much against the nuclear option. The Environmental Defense Fund, for example, opposes any expansion of nuclear power. The EDF recognizes that nuclear power is a possible “wedge” technology for reducing carbon dioxide emissions, but has serious concerns about safety, security, effects on the environment, waste and proliferation.

I thought today that I would try to break down some of the science around nuclear power. Break through the hype, so to speak. I’m a biologist, not a physicist, so I can’t speak about the new technologies that Brook discusses. From a quick glance at the literature it seems his claims regarding the reduction But I can look at a couple of the major issues surrounding nuclear power – safety and environmental effects.

Safety

When most people think of nuclear accidents, two names come to mind – Three Mile Island and Chernobyl. In terms of power generation, Chernobyl is irrelevant for our discussion as it was primarily a military plant designed to make bombs rather than energy. The Three Mile Island accident, the only significant nuclear power accident in the last half century, occurred in 1979 and while it was a major incident there were no fatalities and there was no significant release of radiation or long term detrimental effects on heath. The average radiation dose to people living within 10 miles of the plant was equal to that of a chest X-ray. A study undertaken last year by Roger Levin at the Penn State University of Medicine looked at the incidence of thyroid cancer in residents surrounding the Three Mile Island Nuclear Facility. Ionizing radiation has been linked to increased risk of this type of cancer, so Levin sought to determine if the accident at TMI caused an increase in thyroid cancer in those living nearby. He found no causal link. In my survey of published scientific articles, there has never been a study linking the Three Mile Island accident with any long-term health problems. There has not been a major nuclear power incident since Three Mile Island and the newest generation of nuclear plants are reported to be far safer than the Three Mile Island facility. To be objective, however, I’m not qualified to verify this.

Effects on the environment

One of the biggest impediments to an expansion of nuclear power plants is the NIMBY syndrome. Nobody wants a nuclear power plant near their home. A number of radiological studies have been undertaken that indicate that if a person lifves on the boundary of a nuclear power site they would get more radiation than the general public. However, that amound of radiation is very small – about 0.3% more radiation a year than a person gets from natural sources. While out of favor in the U.S. and Australia, nuclear power has provided much of continental Europe’s electricity since the early 1980′s. For example, France gets 87.5% of the power from nuclear plants. A study undertaken this year by Électricité de France found no significant radioactive contamination in the terrestrial ecosystem, waterways, marine waters or in people surrounding nuclear sites. In other words, while most of us probably would not want to live near a nuclear reactor it is unlikely that it would hurt us if we did.

I did find a couple of disturbing recent studies looking at the effects of thermal discharge on biodiversity. Thermal discharged refers to heated (but non-radioactive water) that is a byproduct of electricity generation at nuclear (and fossil fuel) plants. In some cases, this heated water (which is not radioactive) is discharged into ponds or directly into the sea. A Brazilian research group found that there was a significant decrease in fish species richness and diversity due to thermal pollution from a nuclear power plant in that country. A second study in South Korea found that algal species richness appears to be strongly affected by heated water from a nearby nuclear plant. However, it is worth noting that any form of power generation that uses steam turbines (including coal and natural gas) generates this type of thermal discharge. So, nuclear power is likely neither better or worse for marine biodiversity than any other means of power generation.

I know that this post is going to make me unpopular with some of our readers. The last thing that I want to do is pimp for the nuclear power industry. There are serious concerns about waste disposal and security of nuclear materials. These, however, are political rather than scientific issues and I’m your science guy, not your politics guy. From a scientific point of view, nuclear power is likely as safe as coal or natural gas to both people and surrounding ecosystems. Nuclear power is indisputably better than fossil fuels in terms of greenhouse gas emissions. Hopefully in the long run we can develop a truly renewable alternative, but in the interim nuclear power is, by most measures, a ‘green’ alternative to fossil fuels.