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Heat Wave Shuts Down Alabama Reactor
mdsolar writes "In a first for the US, one of three nuclear reactors at the Browns Ferry nuclear plant in Alabama has been shut down because the Tennessee River is too hot to provide adequate cooling for the waste heat produced by the reactor. This is happening as the TVA faces its highest demand for power ever, reports the Houston Chronicle. This effect has been seen in Europe in the past, forcing reduced generation, but the US has until now been immune to the problem. The TVA will buy power elsewhere and impose higher rates, blaming reduced river flow as a result of drought."
In Soviet Russia, overheating nuclear reactor shuts down YOU!
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
>but the US has, until now, been immune to the problem.
no, not immune. it just hasn't happend until now.
I work at a nuclear power plant. We have a limit for the temperature of the river downstream of our returned cooling water for environmental reasons, not reasons related to the power generation process. I suspect the TVA has a similar requirement.
I noted from the nrc website (www.nrc.gov) that their other reactors are operating at reduced load, which is what our reactors must do to limit the heat input into the river.
So this is nothing remarkable.
Why not just run the river through a refrigerator to cool it down? After all, you can generate the electricity for the refrigerator in the plant.
(I'd patent the idea, but the patent office has a silly rule regarding perpetual motion machines that gets in the way...)
Help! I'm a slashdot refugee.
It ain't about problems with the cooling itself, for that the rivers would need to be far hotter. The problem is enviromental, if you add extra heat to an already warm river you risk that it rises to the point were you destroy the eco-system. Simply put, the fishes get cooked and the algea grow out of control.
This is considered to be a bad thing.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
The cooling problem is a result of TVA's interest in building more reactors. Browns Ferry is now operating with two reactors instead of three because they recently added a reactor. They are also planning on adding a reactor upstream at Watts Bar http://www.tva.gov/news/releases/julysep07/wbu2.ht m adding to the heat load on the Tennessee River. So, next time, they may have to take two Browns Ferry reactors off line at seasonal peak demand. This makes electricity more expensive because it requires buying rather than selling electricity when it is most expensive.
s -selling-solar.html
But, the fairly natural solution to the problem, reducing summer demand through net metering of customer generated solar power, a solution being implemented in 41 states and DC, is hampered in the TVA service territory by TVA's net metering policy: http://www.tva.gov/purpa/net_metering.htm which is a billing period-by-billing period policy rather than an annual carryover policy used in net metering states. Adopting a reasonable net metering policy would allow TVA to become a summer time peak demand power exporter and gain by arbitrage, reducing the risk of higher overall rates it is building for itself by not paying attention to the capacity of the river system to handle the 60% of wasted energy nuclear power generation creates.
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Power when you want it most: http://mdsolar.blogspot.com/2007/01/slashdot-user
Interesting in the article that the journalist doesn't include power generated by hydroelectric dams as renewable energy...
"TVA gets about 60 percent of its electricity from coal-fired power plants, 30 percent from nuclear plants and 10 percent from its 29 hydroelectric dams. Renewable energy sources such as wind and solar account for less than 1 percent."
Any idea why that might be? Political slant? ignorance?
Umm, I mean the water flows through the dam, it goes out to sea, it evaporates, and it rains back up in the mountains and comes through the dam again. Seems pretty renewable to me.... at least some of it is coming back up through that cycle if not all...
If only it were that simple.
Imagine one of those old-style water wheels. Your question is akin to asking, "Why not figure out a way to use the energy of that flowing water without wasting it by allowing it to flow away?"
s/ice cold beer/frosty piss/
If the beer's Bud, don't bother - there's no difference.
It's true I tell you, feller at work's next door neighbour read it in the paper.
To heat domestic water, space heating and even to power adsorption chillers which can reduce AC requirements. Even coal power stations can hit 88% efficient.
t s.html
... Well you decide for yourself.
http://www.helsinginenergia.fi/en/tuotanto/benefi
US power stations are still only 40% efficient because
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The bicycle as a commuter vehicle works only under ideal conditions and only for the young and fit. You won't be taking a bicycle into Buffalo, NY in mid-winter. You won't be taking a bicycle into Houston, TX in mid-summer.
Sure. Now if only someone in Alabama living close to the power plant needed to heat his house in the middle of a heat wave...
"The South never had a "carbon footprint" before yankee glutons moved to Miami and Atlanta."
It sure burned the heck out of wood, Bo! The spelling is "Yankee gluttons", BTW.
"Most of us grew up without air conditioning and were happy that way. We used clothes lines to hang and dry our clothes, not electric driers. Life was good."
HAHAHAHA! When I see local folks volunteering to go back to an AC-free life I'll buy the connection between "no AC" and "happiness".
I still use clothes lines to dry clothes (clothes smell fresher besides the energy savings), but there is good reason AC is popular among non-Yankees. I don't see any nostalgia for doing washing in wooden tubs and ironing it with (aptly named) "sad irons" either. The tubs are planters and the irons are doorstops, the shotgun shacks whose layout helped somewhat with cooling are empty, and (most) of the people don't look the the folks in a James Agee book.
I'm a "Damn Yankee" (the ones that came and stayed) myself, though I'm far more genuinely countrified (and right wing) than most locals.
If you wanted to keep out the sort of Yankees that wouldn't fit, not selling them everything at fire-sale prices would have done it. The Southeast got rich and is getting richer by urban and suburban sprawl, so if ya want things the way they used to be, move into the Deep South and away from the coast.
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
Your open-cycle system will never be more efficient than a carnot cycle at the same temperatures.
I'm afraid Wonko's right. The total efficiency converges to Carnot's. If there is any *usable* waste heat left at the end of a cycle to put into another heat engine, then the first cycle wasn't running at full (reversible) Carnot efficiency.
BTW, if a heat engine were ever to be used in a closed system, then its efficiency would quickly converge to 0%, since the hot source would cool down and the cold source would heat up! The Carnot cycle, as I said in my other post, assumes infinite, constant temperature hot and cold sources, i.e. effectively the same as a system where heat is constantly added to the hot source (by a nuclear reactor) and taken away from the cold source (by a running river) to maintain a constant temperature.
What's purple and commutes? An Abelian grape.
A little noted fact of the cold war is that a very large amount of the US total electrical generation capacity is in the TVA region (Tennessee River - Dependent) The loss of this reactor is serious as the whole USA has no reserve capacity at peak load and with the heat wave over the East USA this is a critical loss. If it were the only reactor in danger this might be of no concern. The US TVA operates 5 big reactors and numerous coal fired plants all of which have the Tennessee River at thermal capacity to cool them and the river is dropping daily.
If heavy sustained rain does not fall on the Tennessee River Valley over the next 3 to 4 months an event which is historically unlikely, the loss of something close to 15 times the Browns Ferry reactor in capacity is likely to hit the USA. There is nothing to pick up the load. The loss of this one reactor is nearly equal to all the wind energy the USA generates. This loss threatens the operations of every one of the 48 US States. With the possible loses in Alabama Power pools and their reactors etc as well as Georgia Power, this poses the very real risk of cutting the energy supply of the USA by a very large fraction. As I write the North Alabama region is short 60 inches of rain over the past 18 months. The US TVA has been drawing down storage for 5 years now. There is no reserve and little prospect of one for some years to come.
I had warning of this imminent event when the City of Huntsville requested from TVA more water for its treatment plant and was turned down for supply. I knew then that the supply was gone.
Never Politically Correct ~ I prefer the facts If you don't like what I say, get a life, or comment yourself.
Generally they don't transport steam, they transport hot but liquid water. See, engineers are not idiots. You must be new here.
Terrorists can't threaten a country's freedom and democracy. Only lawmakers and voters can do that.
The reactor was shut down because the water exiting the plant's cooling system exceeded an average of 90 degrees F over a 24 hour period. The plants have an agreement with the state to limit the temperature of the water they put into the river. The water in the river is not even remotely 90 degrees F.
Brown's Ferry also just recently started one of its reactors after a long downtime, so this only kicked us back a few months. It's not a big impact to the nation's grid, not even to the local area.
As for why we don't recapture the energy in the heated water to make even more power, well, they just didn't think it was necessary back when we used to build power plants back in the 60's. Investing money in anything nuclear in the US is political suicide.