I just heard an NPR broadcast, reporting that a scientist has found that the top layers of the earth’s oceans have increased in temperature (by around 0.1 C, over the past 50 years). Since this represents an enormous amount of thermal energy, can this be tapped?
Years ago, I read about the work of the French engineer, Georges Claude. Back in the 1930’s, he built an experimental power plant, on the Bay of Matanzas, in Cuba. Basically, he ran a low-pressure turbine on the temperature difference between the surface water (around 80 deg. F), and the deep bottom water in the bay (around 40 F). Has anybody repeated Claudes’s work? I assume we’ve advanced a bit in turbine design since 1930-wouldnt we be able to get unlimited energy from the oceans?
This looks like it was meant for GQ. Lemme bounce it over there. Unfortunately, the power of our server isn’t unlimited; I hope it doesn’t get lost along the way.
The amount of energy that we can extract via this method is probably huge and might be unlimited for all practical purposes but it will not be free. The turbines cost money the plant must be maintained.
google is great search for Georges Claude Power.
http://www.sciencenews.org/20000715/timeline.asp
http://www.sciencenews.org/20000715/timeline.asp a paper on the subject.
Apparently Georges also invented the neon sign.
I blew making the link to the paper
http://www.wws.princeton.edu/cgi-bin/byteserv.prl/~ota/disk3/1978/7815/781504.PDF
Keep incrementing the last number before PDF to get the next chapters.
Not having read the links, my first question would be how much energy can be extracted per unit area? If that is a small number, than you may need a ridiculously large power plant to provide enough power to be useful to anyone.
Interesting idea though.
There is no such thing as a free lunch. If you extract energy from the temperature differentials in the ocean, eventually, if you extract a LOT of it, you’re going to change the temp levels in the ocean (even if only at deep waters). That’s got to have some sort of ecological effect. You can’t fool Mother Nature.
Yes, but since many climatologists argue that the oceans are the biggest mover in global warming (rise in ocean temp. has far more impact on global weather, etc., than rise in air temp.), couldn’t we help alleviate the damage we’ve already caused? Perhaps by sucking some of that thermal energy back out of the oceans, we could prevent a global catastrophe.
Old idea resurfacing. On Maui they have plans to get energy this way but it’s not yet practical. The temp of the water on the ocean floor is low & on the surface, high.
Might be practical for them cause they have no other way to get energy from nearby states.
You suck it out of the oceans, and put it where? Most likely, it stays here on Earth.
Just making a guess here, but I don’t think they are pumping water out of the ocean Anth.
I think with the two temparature differences in the deep water and the surface will cause sort of a current. That current (I assume) will spin a turbine, therefore spinning a Generator. So instead of burning coal to boil water and turn the turbines or causing a nuclear reaction to boil the water, (Causing the steam to turn the turbines I mean) they will not have to boil water at all.
I looked at the science news link but am not presently ready to download the PDF file. It said that the cold deep water was to be used as “cooling water” for the power plant. Are you sure he was trying to get energy by using it? I’m not quite sure how he meant to extract the thermal energy (presumably from the warmer surface water).
I think I heard the same NPR report you did and I doubt there’s any way to effectively extract the vast amount of thermal energy dispersed in such a huge amount of water. If I recall correctly, many power plants operate by heating the water up to the point where the water is moving fast enough or evaporates into steam to turn a turbine. This water in the ocean is not heated up to anywhere near the degree it would be in a power plant.
You could generate tidal power from the oceans as a renewable resource, but I have no idea how you could go about extracting such dissapated thermal energy.
Amedeus I don’t follow you, how does having cold and hot water generate an electrical current? A convection current, yes (which doesn’t occur too often because the cold water is usually at the bottom of the oceans). An electrical current? I have no idea how that would work.
Whenever you have two supplies of material (called “resevoirs”) at different temperatures, you can get useable energy out of them: The hot resevoir gets cooler, and some of that energy goes towards heating the cool resevoir, and some is usable output. This would, in fact, produce a net cooling of the oceans… However, that energy goes somewhere, and after it’s down lighting up your house or whatever, almost all of it gets converted to heat, and almost all of that heat stays on Earth, so there’s no net cooling of the planet that way.
I know that. I was asking because it seemed like the issues of heat and the conservation of the heat within the biosphere were being mixed. Like Chronos said, I notice on preview.
It’s hard to get a serious amount of hydraulic potential because the ocean is already pretty stratified the way it should naturally be - it is already at a low potential energy. I do know there are all sorts of plans for trying to come up with greater potentials, including one where they proposed having a desalinization process at great depths, where the changing water density would drive fresh water up and out of the ocean to turn a turbine. These systems typically have tremendously low efficiencies - so low they do not cover the energy cost of making and maintaining the equipment. Everybody loses then.
The article states that the power plant works by vaporizing a liquid with the higher temperature surface water then using the gas to run a turbine. The vapor is then condensed by cooling it with the cold water you have pumped from deep below. Then the liquid would be boiled again by the warm water.
It also goes on to state that Georges’s power plant generated 23 Kwatts of power. Unfortunately it used 80 KWatts to run the pumps. This article was written in 1976 the hieght of the old energy crisis as was ment to be used to decide how much congress should fund more research into this type of plant.
The article didn’t really propose using the power for cities in the US because there are a limited number of places where the surface temperature was warm and there was near by cold water. The thought is would best be used for off shore aluminum refining plants or some manufacturing process like that. They also go on to point out the really huge amount of water that needs to be pumped. For a 100 MW plant (this is pretty small) 30,000 cubic feet of water needs to be pumped. They say this is 1.5 times the flow of the Patomic river.
That is 30,000 cubic feet of water per second.