According to many 'Green' organisations nuclear power is very expensive, in fact, one website claims it is three times as expensive as electricity generated from fossil fuels.
According to the World Nuclear Association it is about the same as electricity generated from fossil fuels.
Now if the two sides were out by 10% it could be explained away, but how come the two sides are out by a factor of three?!
It can be explained by assessing what each side in the debate is looking at.
Nuclear Power in Britain has been an expensive failure. After the second world war Britain was skint but wanted a nuclear weapons programme, and on a shoe-string budget set about it with no thought for waste disposal. As a consequence Sellafield is a radioactive mess which is going to take decades - and tens of billions of pounds - to clean up. In addition, the early Magnox nuclear power statons were built with no thought for their eventual decommissiong and it is believed they will cost up to £3bn each to decommission. ref: www.world-nuclear.org
Also, every nuclear power station in Britain has been built to a different design. Everyone understands that if you build things on a bespoke basis it is expensive and if you mass-produce something it is cheap, and that goes for cars, widgets and nuclear power stations.
If you look at nuclear power in Britain then you may indeed - rightfully- claim the whole thing is extremely expensive.
France, on the other hand, began their nuclear power station building programme later on and were able to learn from the mistakes of others. They built dozens of power stations to similar designs and therefore they managed it cheaply and quickly. It has been a big success story for the French.
The conclusion to this quite straightfoward. If you look backwards through the history of nuclear energy then it has indeed been very expensive. However, if you build a nuclear power station today, to an established design, then the decades of knowledge and experience mean that it is as cheap as any other form of electricity.