So how expensive is a nuclear power plant?

Wall St Journal reports that utility companies (electric companies) are cringing from the $5 to $12 billion dollar quotes on new nuclear plants. The article goes on to say that the existing nuclear plants built in the 60's and 70's cost about $3 billion. Hmm. There's been a bit of inflation since the '70s. In the '70's a new Caddy went for $10K. A 2008 Caddy goes for $43K. If the cost of a nuclear plant is only up from $3 to $12 billion, that's no big surprise to me, and it shouldn't be a surprise to electric companies or the WSJ.
Second, you gotta wonder how much gold plating has been done on the designs. The word "nuclear" raises the cost of things. For instance, the mess tables on nuclear aircraft carriers cost more than the mess tables on oil fired carriers. What with the current population of ambulance chasing lawyers, to say nothing of skittish insurance companies, every conceivable safety device will be incorporated whether it does any good or not. Nuclear safety people make Alice in Wonderland look rational. As you may remember Alice once met a white knight. The knight's horse had spiked steel anklets on all four legs. When Alice inquired about them, she was told that the spikes protected the horse against shark bites. Alice asked how often the knight's horse had been attacked by sharks. The knight replied the horse had never been bitten which meant the spiked anklets were doing their job. I'm sure the new nuclear designs have plenty of expensive spiked anklets protecting against shark bite.
If the plant cost $10 billion, it will take a long time to pay itself off. I pay $0.10 per kilowatt hour, of which half goes to the generating company and the other half goes to PSNH who owns the power poles, transformers and electric meters. A nuclear plant will generate 1000 megawatts. Run the plant for an hour, and you bill $0.05 times 1,000,000 kilowatt/hours, or $50,000 an hour. $10 billion divided by $50,000 an hour means 200,000 hours (about 22 years) to pay off the construction costs. That's a long time, and this back of the envelope calculation ignores operating costs, fuel costs, taxes, and interest on the debt, all of which would stretch out the repayment time. Better go for the low end $5 billion dollar plant.