Current Nuclear Plants still leave tax payers in debt billions after service lifespan while running beyond that life to squeeze out amortize costs while further adding waste on to a pile radioactive stockpile destined for nowhere while fuel sources get more scare than oil? Nuclear energy answers are in this blog, but the current program is in more trouble than our nations job market and economy.
NY Times ...Contractors generally designed plants to last for 40 years — a standard enshrined in the United States in the adoption by the Nuclear Regulatory Commission, or N.R.C., of a 40-year licensing regime. A large part of the world's installed nuclear power capacity is now coming to the end of that designed life span.
Caught between approaching retirement deadlines and public opposition to new plants, industry operators are pushing to extend the life of their plants to 60 or even 80 years — and this despite problems of premature aging of major components that have already obliged many to replace their plants' steam generators at heavy capital expense.
Running plants longer is one way to recoup the extra cost and raise returns on investment over the full life of the plant. But it has safety implications.
The 40-year life span was a design specification, said Guillaume Wack, director for nuclear plants at the Autorité de Sûreté Nucléaire, or A.S.N., the French nuclear regulator.
"It's like a car," Mr. Wack said in an interview. "The manufacturer says it will run for 100,000 kilometers" — 60,000 miles — "and last two years. That's the theoretical life...
...Since the 1970s, regulators and operators have identified premature aging problems including vibrations in pipes, with consequent cracking, leaks and ruptures that in turn cause severe corrosion, leading to worse leaks and ruptures. Some of these result from high fuel burn rates, Mr. Wack said.
Most plants worldwide have, in fact, already replaced their generators, at a cost of around $50 million for each new generator, after operating for 20 years or less, according to Steve Kerkedes, press officer for the Nuclear Energy Institute, an industry lobby group.
The problem is further complicated by the fact that each reactor heats three or four generators. Anything done to one must also be reproduced on the others in order to avoid pressure imbalances: If one generator has to be changed, all the others must be swapped out, Mr. Wack said.
Most plants worldwide have, in fact, already replaced their generators, at a cost of around $50 million for each new generator, after operating for 20 years or less, according to Steve Kerkedes, press officer for the Nuclear Energy Institute, an industry lobby group.
While extending the operating life beyond 40 years may help to amortize that cost, it intensifies another problem — finding replacements for other components. Manufacturers are few, and the backlog for many parts is long.
...Still, there is no proof that the reactor vessel or the containment building is sufficiently robust to last beyond 40 years. Cracks in vessel heads, the lids that cover reactor vessels, were discovered in various reactors around the world as long ago as 1991, French and U.S. regulatory documents show.In addition, N.R.C. documents show, design flaws identified in 1991 raise the specter of possible long-term fatigue degradation in the reactor vessels themselves due to the heat and high radiation to which they are subjected. A leak in the reactor vessel would result in a core meltdown — the most serious accident possible — with an inevitable release of radioactive materials, Mr. Wack said.
This year, some plants in the United States will hit the 40-year mark but will continue to operate under licenses that have already been renewed. Please read full at NY Times
