For those who care a lot about climate change and reducing the carbon intensity of our energy systems, nuclear seems like a bit of a Faustian bargain. On the one hand, nuclear power plants have all of the advantages of fossil fuel plants – they offer controllable and (in the hands of skilled operators) highly reliable electricity supplies; can be built at very large scales (and increasingly smaller scales), and cost very little to operate once they are built – but have basically none of the greenhouse gas emissions. On the other hand, there are serious challenges that come with having an electrical system that depends a lot on nuclear. Plants are very expensive to build, which is why the cost of nuclear energy is so high (more than 6 times as much as wind power). Managing waste products has been difficult, particularly in the United States, where most of our waste is stored at the power plants in a "temporary" mode. Finland is about to begin storing their waste in a safe, long-term facility deep within the Earth, but a similar solution in the US, at Yucca Mountain in Nevada has stalled due to politics. And when nuclear power plants fail – as happened at Three Mile Island in Pennsylvania; Chernobyl in what is now the Ukraine; and most recently Fukushima Daichi in Japan – the results can range from striking terror into the hearts of thousands of people (as was the case with Three Mile Island, which as far as we can tell did not actually kill anyone outside of the plant) to utterly catastrophic (Chernobyl and Fukushima). As bad as these accidents are, it is important to understand that nuclear power plants cannot explode like a nuclear weapon — a fact that not everyone is aware of.
Part of the reason that nuclear energy can become an emotional topic is that nuclear power plants are extremely complex, despite their basic similarity to any other power plant that uses a steam turbine design. While it’s easy to understand how burning coal or natural gas can produce steam (and greenhouse gas emissions) to run a power plant, how nuclear reactions manage to create steam is a bit more complex. When you add in the thorny problem of how to manage a waste product that could potentially pose environmental and human health risks for thousands of years, it’s easy to see why a number of countries are deciding that the potential social costs are not worth the benefits. On the other hand, the global nuclear power industry actually has one of the best safety records of any energy source. Because nuclear power plants can be operated relatively safely in the right hands and because producing electricity from nuclear plants releases virtually no air pollution, some countries are actually seeking to rapidly increase their nuclear energy production. But, as we saw in the introduction to this module, on a global scale, nuclear energy production has not been growing over the past 20 years.
Is nuclear power truly renewable? The supplies of uranium ore that we know about today, given our current rate of consumption, will last for more than 150 years; increased exploration could increase that by a bit, but the fact remains that it is a finite resource. So, nuclear energy, as it is mainly produced today, using the isotope U-235, is not truly renewable. But, there are other types of nuclear reactors called "breeder" reactors, which use the far more abundant stable isotope of uranium, U-238, as the primary fuel. Because there is so much U-238, nuclear energy generated with these breeder reactors is virtually limitless.