Water Shortage Shuts Down TVA Nuke Plant

I posted this yesterday at Daily Kos – under a different title “Nuclear is Not the Answer”.  The pro- nuke shills immediately descended upon the diary and I’m only now coming up for breath.  Maybe some folks here will read it for what it’s about – our current (and future) shortage of cool water is a major problem for nuclear plants.

Here’s the diary:

Nuclear power is not the answer to global climate change. Other than the safety issues connected to nuclear waste, which are pretty well-publicized, there is a major problem with thermal load, which is not so well known.

Nuclear plants need cool water for cooling.  Hotter water temperatures in the Tennessee River this summer caused TVA to suspend operations at their Browns Ferry Plant.  Browns Ferry is downstream from 3 other TVA nukes which had already heated up the river to a point to prohibit further heating.

France and Germany have had the same problem – in the 2003 heat wave.  The rivers on which their nuclear plants were built were heating up beyond their environmental agenies’ standards for aquatic life. A choice had to be made between nuclear power and the health of their rivers and aquatic life. 

As folks who read the great diary this weekend on Atlanta’s water shortage must recognize, with climate change and rising temps, the cool water necessary for nuke plants will be a scarcity

In August,  the Tennessee Valley Authority had to shut down one of three units at the Browns Ferry nuclear plant because water drawn from a river to cool the reactor was too hot.

Nuclear power plants use water as a cooling agent. Two gallons of water are needed by nuclear power plants for every kWh they produce.  After the water is used, it is put back into a water supply at 9-20 degrees C warmer.

From the TVA website:

The nation’s largest public utility shut down Unit 2 about 5:42 p.m. CDT because water drawn from the Tennessee River was exceeding a 90-degree average over 24 hours, amid a blistering heat wave across the Southeast.

“We don’t believe we’ve ever shut down a nuclear unit because of river temperature,” said John Moulton, spokesman for the Knoxville, Tenn.-based utility.

He said TVA would compensate for the loss of power by buying power elsewhere. The utility announced earlier Thursday that it was imposing a fuel surcharge on customers because of lower hydroelectric power production caused by drought conditions.

Two other units at the plant were operating, as well as towers to cool the water. But searing temperatures and a lack of cooler water in the upper part of the Tennessee River system made it too difficult to provide cool water for all three reactors. There was no safety threat posed by the shutdown.

Moulton said the average high temperature Thursday was 103 for five of the largest cities in TVA’s coverage area: Huntsville and Knoxville, Chattanooga, Memphis and Nashville in Tennessee “It’s the hottest in 20 years,” he said..

TVA: http://www.tva.gov

From the local paper, the Athens News-Courier:

High water temperatures in the Tennessee River have forced the Tennessee Valley Authority to shut down the Unit 2 reactor at Browns Ferry Nuclear Plant in Athens.

TVA spokesperson Terry Johnson said Thursday night the utility had to shut down one of the three reactors at the plant about 5:42 a.m. Thursday when the water temperature in the river went over the limit.

“When the water temperature remains at an average of 90 degrees or higher over a 24-hour period, we have to take steps to try and reduce that temperature,” Johnson said. “We had reduced power output from all three units by 15 percent earlier, but that did not bring the temperature down enough.”

The massive cooling towers at the plant usually are sufficient to control the temperature of water released from the plant, Johnson. Due to the historic heat wave currently enveloping much of the Tennessee Valley, however, it now may be necessary to bring cooler water down from tributaries in East Tennessee, Johnson said.

TVA cannot determine when the Unit 2 reactor may go back on line, Johnson said, “it just depends on when we can bring the water temperature down to an acceptable level.”

http://www.enewscour….

We’re still in a heatwave in the Southeast and an Exceptional Drought in Tennessee, northern Georgia and Alabama. http://drought.unl.e…

As early as June, the water level at Douglas Lake in Dandridge, Tenn., upstream of TVA’s nuke plants, was below average. TVA officials said at the time that unless the area gets unexpected rainfall this summer, lake levels are unlikely to rise.

Effects of increased water temperature on aquatic biota include thermal shock. Aquatic life adapted to a certain water temperature can go into shock when the temperature is changed even 1 or 2 degrees.  Oxygen dissolved in water decreases.  The rate of photosynthesis increases, which increases the amount of plant growth, developing eutrophic conditions.  The metabolic rate of fish increases, which increases their need for oxygen.

Thermal pollution may cause possible  migration of organisms to another, more suitable environment, and to in-migration of organisms that normally only live in warmer waters elsewhere. As a result there is the problem of compromising food chains of the old and new environments. Biodiversity can be decreased as a result.

Changes of even one to two degrees Celsius can cause significant changes in organism metabolism and other adverse cellular biology effects. Principal adverse changes can include rendering cell walls less permeable to necessary osmosis, coagulation of cell proteins, and alteration of enzyme metabolism. These cellular level effects can adversely affect mortality and reproduction.

Under drought conditions,  less water is absorbing more heat.  Water flow is lower and slower. There is insufficient water to function as a heat exchanger.  The Water gets hotter.  This summer, Chickamauga Lake near  Chattanooga had a temperature of 89 degrees, making the cooling of the TVA’s Sequoyah Plant, upstream of Brown’s Ferry inefficient.

I’ve written before about the great success my husband and I have had with the 4kw of photovoltaic panels we put on our roof last year.  I really think that solar is the answer to our need for a clean, renewable energy source. Even in what I always considered cloudy, humid, wet Tennessee, we made plenty of solar power this year.

Of course, we’re also in a sort of mini-climate change here right now. Lot’s of blue sky, sunny, dry days – more like a Claifornia or Mediterranean type climate.  I fear the beginning of desertification.

We won’t have water to drink, much less cool nuke plants.