#1 Drought Threatens To Cripple Southeast Nuclear Industry
Posted: Tue Jan 29, 2008 1:12 pm
Dailytech
So now... not only these plants will have to shut down, but the already over extended north america power network will be stretched even further at a critical point.Drought may shut down plants, lead to much higher energy bills in the Southeast
Whether climate change is a good or bad thing is open to debate, but change indeed appears to be happening in the Southeast U.S., which is being hit with record droughts. These droughts turned neighbors Florida and Georgia against each other in Federal courts over water rights for the water flowing into the Everglades. It also is having some startling consequences on one major U.S. alternative energy source.
Nuclear power is only recently gaining newfound respect in the U.S. and abroad, with the first application for a new nuclear plant in 30 years filed late last year and Canada pushing ahead to restart one of its major research reactors after criticism on government inactivity. Despite these modest gains nuclear remains much maligned among the U.S. public and still has yet to win broad support. Residents in the Southeast may soon be learning, though, that they didn't know what they had till it was gone, as the drought threatens to cripple the southeast nuclear industry and send energy costs in some areas skyrocketing.
Water is a key part of the process of generating nuclear energy. It is used to cool the reactor core and to create the steam which is used to drive turbines to convert the heat energy from the reactions into mechanical and finally electrical power.
Plants tend to fall into two categories. The first have tall cooling towers that discharge most of the water as steam, which is lost into the atmosphere. Others lack the tall cooling towers and exhaust hot water into reservoirs; however they are limited by environmental regulations as to how much hot water they can purge. These restrictions are due to the fact that the water is so hot it can easily kill fish and local plants. Exhausting heated water does recycle a small portion of the used water back into reservoirs, but much of the water still evaporates as it exits steaming hot.
Spokeswoman Julie Hahn for Progress Energy Inc., which operates four reactors in the drought zone, explains the massive water needs of the energy producing giants. She says one Progress reactor, the Harris reactor, intakes 33 million gallons a day, with 17 million gallons lost to evaporation within its megatonic cooling towers. Duke Energy Corp.'s McGuire nuclear plant consumes more than 1 billion gallons a day, though a lesser percentage is lost to evaporation than with the Harris reactor.
The situation has gotten extreme, and numerous plants have been shut down, are preparing to temporarily shut down, or are throttling back production. Nearly a fourth of the nuclear reactors in the U.S., 24 out of 104, are in drought afflicted regions. Nearly all, 22 of these 24, rely on lakes and rivers for their water needs. The Nuclear Regulatory Commission, the U.S. government body which regulates the nuclear power industry, has set minimum allowable water levels for these water sources. Most of the water sources are approaching these minimum levels. Falling below means a government mandated plant closure.
Even if the government relaxes its restrictions, the water levels are forecasted to drop below the level of the intake pipes for many of these plants. At other plants, the water is becoming too hot under the sun and from stored up heat to be used for cooling purposes.
Robert Yanity, a spokesman for South Carolina Electric & Gas Co. states grimly, "If water levels get to a certain point, we'll have to power it down or go off line."
There is no easy answer. The intake pipes are large and often up to a mile long and concrete and extending them would require months of effort and an overhaul of the plants pumping systems and an unpleasant price tag of millions of dollars. And the pipes could only dip so deep before they started sucking up sediment and organic materials, leading to blockages.
The shortage affects about 3 million customers in parts of the Southeast who get their power solely from nuclear energy. Even more people will likely be affected as the quasi-governmental Tennessee Valley Authority's (TVA) relies on 30 percent nuclear power to fuel the energy needs of its 8.7 million customers.
The plants need over a foot in rainfall over the next month to stay in business, but there is no relief forecasted in site. Donna Lisenby, executive director of the Catawba Riverkeeper environmental group that tracks conditions Lake Norman and other lakes along the 225-mile Catawba River system, bemoans, "If we don't get at least 10 to 15 inches of rainfall in January, February and March, lake levels could be lower in the fall of 2008 than they were in 2007 -- and that could be a disaster."
The Progress Energy Harris plant is currently at 218.5 feet, 3.5 feet above the legal limit. Progress officials say if the water dips below the limit, they will be forced to close and buy power from other sources. Duke's McGuire nuclear plant's lake dropped 4.5 feet since last year and only needs to drop one more foot to be below the legal limit, mandating closure.
The TVA reactor at Browns Ferry in Alabama already shut down once in August 16, 2007 due to the discharged coolant being too hot. As reservoir temperatures rise, this is expected to become a much more regular occurrence.
An additional call for concern was raised by David Lochbaum, nuclear project safety director for the Union of Concerned Scientists, who argues that most of the plants can't take the wear and tear of repeated shut-downs and start-ups.
So aside from forcing many Americans to adopt less clean source of energy, what exactly will these possible shutdown potentially cost them? Daniele Seitz, an energy analyst with New York-based Dahlman Rose & Co states, "Currently, nuclear power costs between $5 to $7 to produce a megawatt hour. It would cost 10 times that amount that if you had to buy replacement power -- especially during the summer."
Nuclear power, while unappreciated, provides cheap alternative energy power. With climate change threatening to shut down many of the reactors in the Southeast, many people may start to realize how great nuclear power really was when faced with the harsh reality of when it’s gone.