Why do nuclear power plants raise the temperature of sea water?

Why do nuclear power plants raise the temperature of sea water, and how does this change the environment that the sea life is accustom to?

Why do nuclear power plants raise the temperature of sea water?
Rok is correct but I have this to add... you do have a choice how much heat you emit. The heat from a nuclear reactions is used to create steam and run a turbine, and some of the heat from the waste steam is recaptured. There comes a point, though, when it is no longer economically advantageous to install heat exchangers and you just let the waste heat go.



This does not mean that it cannot be recaptured - only that we have decided that it is not worth capturing. Depending upon the value you put on discharging water at "environmentally friendly" temperatures you can design a plant any way you want.



Half of the battle is putting a value (or penalty) on environmental burdens. If there is no way to factor environmental issues into the economic equation then they will be overlooked - because it is obviously more expensive to do things in a friendly manner than in an irresponsible manner.



As engineers we face this all the time. We know how to do something the right way, but have a hard time justifying it to shareholders when there is a cheaper way. Believe it or not we are usually happy when a piece of legislation comes down because then we have an excuse to do the right things that we wanted to do all along.



It may surprise you that the industrialist ends not to be the enemy. The real enemy is the guy next door who screams about the environment while investing his 401K in whatever fund or company gives him the highest economic return.
Reply:nuclear power plants raise water temps because they use the water as a coolant. the plants are placed next to a river or something of the sort so they can easily have the water flow in, cool things down, and flow right back into the stream/river. when the water goes back, its much hotter than it was to begin with.
Reply:Simple as it gets. Nuclear power plants give off max heat, and I mean M-A-X heat. Without water to cool them down they could either explode or melt down, given the right combo of situations. So, they're placed near a constant source of water. Prob is, over a long-enough time the warmer water from the plant can actually raise the water's temperature. This is a long-used argument against such plants by anti-nuke groups, by the way.
Reply:I MIGHT HAVE WORDED IT DIFFERENTLY BUT I CONCUR WITH ROK