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World's Largest Ocean Thermal Power Plant Planned For China
cylonlover writes "Lockheed Martin has been getting its feet wet in the renewable energy game for some time. In the 1970s it helped build the world's first successful floating Ocean Thermal Energy Conversion (OTEC) system that generated net power, and in 2009 it was awarded a contract to develop an OTEC pilot plant in Hawaii. That project has apparently been canceled but the company has now shifted its OTEC sights westward by teaming up with Hong Kong-based Reignwood Group to co-develop a 10 MW pilot plant that will be built off the coast of southern China."
This is ridiculous, the length limit algorithm needs to be updated, these jackoffs are breaking it somehow, I shouldn't have to hold Page Down for 2 seconds to skip past one comment.
In Stockholm, Sweden we have since many years been running the worlds largest heat pump facility, 225 MW. http://sv.wikipedia.org/wiki/Hammarbyverket.
It's using waste water from a nearby waste water treatment facility that serves a large fraction of the Stockholm metropolitan area of some 2M people.
Maybe I missed it but the picture gives me a vague impression that waves have something to do with it but I didn't see them mentioned? I suppose the water movement wouldn't be much use though.
No, it has nothing to do with waves. It uses the ocean's thermal gradient as a power source: because there is warm water on top, and cold on the bottom, we can use the difference to generate power (much like heat from a conventional power plant). Keep in mind it won't be very efficient, since the temperature difference is relatively low, but since you have quite a lot of seawater to utilize, efficiency isn't terribly important.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
This system requires deep water. The deeper the better. Think over a mile deep.
Seawater at that depth is rich in nutrients. Ocean thermal plants could be combined with aquaculture to make them more cost effective. After the water is drawn up and warmed in the heat exchanger, it is released at the surface. The nutrients result in a plankton bloom that can be eaten by fish, shrimp, oysters, etc.
Kinetic energy of water is 0.5*mv^2. For 1 ton of water moving 1 m/s, that's 500 joules per ton. If it's moving at 5 m/s (about the max you'll see in tidal areas), that's 12.5 kJ/ton.
Water has a specific heat of 4.2 kJ/kg*C. If there's a 1 degree temperature differential, that's 4.2 MJ per ton. You have to go a bit deep to get to colder water, but by about 1km down it's around 4 C. So relative to tropical surface water, you're talking about a 25 degree difference, or an energy potential of 100 MJ per ton. Nearly 5 orders of magnitude more per ton than the kinetic energy in tidal currents.
The catch being that it's much more difficult to extract power from temperature differentials than it is from kinetic energy. If it were easy, every car engine would have a stirling engine alongside it to extract energy from the waste heat. But stirling engines generate so little power per mass of the engine that it's more efficient just to forgo the additional weight and dump the waste heat via a radiator.
Back before we became a bunch of short-sighted corporatists who laugh at anything that doesn't turn a profit in one quarter.
I swear to God...I swear to God! That is NOT how you treat your human!
If it works China will use the partnership to steal any useful technology, produce it themselves and out compete Lockheed. See partnerships with high speed train manufacturers and solar cell production.