Original sentence: All other things being equal, the bigger our power plants and power lines get, the more frequent and widespread regional blackouts will become.All sources of electrical power sometimes fail, differing only in why, how often, how much, for how long, and how predictably.Also, nuclear plants must instantly shut down in a power failure, for safety reasons, but for nuclear-physics reasons, they can’t be restarted quickly.Because about 98% of power failures start in the grid, bypassing the grid (by shifting to efficiently used, diverse, dispersed resources sited at or near the customer) enhances reliablity, and a portfolio of many smaller units is unlikely to fail simultaneously: its diversity makes it particularly reliable even if its individual units are not.During the August 2003 Northeast blackout, nine normally operating U.Even the most reliable giant power plants are intermittent: they fail unexpectedly, often for long periods.For the first three days, when they were most needed, their output was below 3 percent of normal.Heavily nuclear-dependent areas are particularly at risk of intermittency because drought or a terrorist incident could close many plants simultaneously.Normally operating nuclear plants must shut down, on average, for 39 days every 17 months for refueling and maintenance.Of all 132 U.On 16 July 2007 a severe earthquake hit the Kashiwazaki-Kariwa Nuclear Power Plant in Japan.Some release of radioactive material occurred and all of the reactors were shut down and are expected to remain closed for damage verification and repairs for at least one year.The big transmission lines that nuclear plants require are also vulnerable to lightning, ice storms, rifle bullets, and other interruptions.The plant with seven units is the largest single nuclear power station in the world.To cope with such intermittence in the operation of nuclear (and large fossil-fuel power plants) electric utilities must install a reserve margin of extra capacity, roughly 15 percent, some of which must be spinning ready for emergency use.Twelve days of slow restart later, their average capacity loss had exceeded 50 percent.nuclear plants built (52 percent of the 253 originally ordered), 21 percent were prematurely and permanently closed due to reliability or cost problems, while another 27 percent have completely failed for a year or more at least once.nuclear units had to shut down