Let’s go nuclear!

Since yesterday (14 April 2012) was the 30 year anniversary of Wellington (New Zealand) being nuclear-free, I thought it would be fitting to do a post looking at nuclear power, and all the reasons why it’s not the solution to the energy crisis. It’s a bad idea on so many levels, I hardly know where to start, but just for the fun of it, I will first look at the advantages of nuclear.

Yes, I will admit there are advantages to nuclear. In fact, there was a time when I too thought we needed to get more of our energy from nuclear. It packs a lot of energy: one pellet of uranium dioxide is only about the size of an eraser on a pencil, but it contains the energy equivalent of a ton of coal. Mining uranium is also less damaging than mining coal. And yes, you get far lower CO2 emissions and other air pollutants from a nuclear power plant than a coal power plant (but large amounts of CO2 are emitted in the construction of that nuclear power plant).

So much for the advantages – it’s not my fault it’s such a short list! Now for the disadvantages.

From a purely practical point of view, there is no way we can produce enough nuclear power to meet the world’s energy needs. If you don’t believe me, check out Tom Murphy’s blog post, where he crunches the numbers. Apparently we would need 1 million ton of uranium a year, but the World Nuclear Association reckons the total amount of uranium that exists worldwide is 5.4 million tons. So we have less than 6 years’ supply of uranium at current levels of use. And then I haven’t even talked about the rate at which we would need to start building nuclear power plants. According to the Oxford Research Group, we would need to build one nuclear power plant every week for the next 70 years! And it costs about US$14 million to build just one…

So we know uranium dioxide pellets contain a lot of energy. That must mean nuclear power plants are very energy efficient, right? Uhm, no. Energy returned on energy invested (EROEI) refers to the amount of usable energy you can get from a particular energy resource compared to the amount of energy expended to obtain that energy resource. For example, if it takes 9 units of energy to produce 10 units of ethanol fuel, the net energy ratio is about 1.1. And of course anything less than 1 is a net energy loss. The net energy yield from passive solar power, for example, is 5.8. From oil, it’s 4.5. Anyone want to guess what it is for nuclear? Some people might not like to hear it, but it’s a measly 0.3. That’s right – it’s a net energy loss. Part of the reason for that is because is takes so much energy to extract and process uranium ore, build and operate nuclear power plants, and then of course store the radioactive waste. But even if you don’t look at the entire life cycle of a nuclear power plant, a nuclear power plant loses about 75% as waste heat, so it’s inefficient even before you add the energy losses from mining, dealing with the radioactive waste, etc. The only reason nuclear power continues to exist on the open market is because of huge taxpayer-funded subsidies.

Then there are the environmental considerations, which are reasonably well-known. First the uranium must be mined, and that has certain environmental impacts. And the uranium fuel in a reactor lasts only 4 years or so before it must be replaced. The spent fuel rod assemblies need to be kept in water-filled, steel-lined concrete basins for several years to cool down, before being transferred to dry casks made from concrete and heat-resistant metal alloys. Because the pools and casks are usually outside the reactor buildings, they are vulnerable to accidents and sabotage. The nuclear power plants themselves also don’t last forever, and eventually need to be dismantled, leaving more radioactive material to be safely stored. And all of these wastes need to stored for at least 10,000 years. After 10 years, a spent fuel rod still emits enough radiation to kill someone standing 1 metre away in less than 3 minutes.

So maybe we just need to spend a bit more time and money on research to improve nuclear fission efficiency? But research has been ongoing since 1949, and in the US, about $70 billion a year is spent on research and development for nuclear fission and fusion. That’s more than half of total US expenditure on energy research and development. How much more do we need to spend on it before people accept it’s not feasible?

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