Slashdot Mirror
Harnessing Vertical Sea Temperature Gradient
Sterling D. Allan writes "Sea Solar Power Inc., run by three generations of James Hilbert Andersons, has developed a solar power technology that does not fluctuate with the weather, but is available constantly. Their solution is to harness the solar energy stored in the sea by tapping the thermal gradient that exists naturally between the surface and deep waters, using a reverse refrigeration cycle. The modeling and testing done by the Anderson family over three generations since 1962 predicts that the cost of energy generation through this method will be within a price range comparable to nuclear, coal, natural gas, and other contemporary grid power plants. Ocean Thermal Energy Conversion, or OTEC, was invented in 1881 by a French scientist, Jacques Arsene D'Arsonval. SSP should be ready to build their first full prototype 2-3 years from now."
Nuclear power doesn't derive its energy from the sun.
My blog
I knew I missed something...
Incidentally, does the thought of messing around with oceanic temperature gradients bother anyone slightly? It's probably not on a scale nearly wide enough to destabilise any currents, but it'd be good to have an oceanographer's opinion on this.
For the love of God, please learn to spell "ridiculous"!!!
I did a report on OTEC when I was in junior high--18 years ago--based on an article in Scientific American. There are prototype facilities in a number of countries--I visited the facility in Hawaii five years ago, which was at least a decade old then.
It's an intriguing idea, but this smacks of somebody trying to get publicity to bring in venture capital or something of the sort.
Somebody please think of the bird decapitations.
There are no trails. There are no trees out here.
The article says that the current world consumption of energy is about 1/300th of the energy available from the oceans in this way. I'm not sure if that's a tiny fraction or not, actually. Local effects on the ecology could be significant for a large power generation facility.
But the article also says that they can produce fresh water as a by-product, and that the process works best in the tropics (i.e. the developing world), so this might have a chance, since it'd probably be better for the environment than more fossil fuel consumption.
Have you read my blog lately?
The problem with any power generation scheme is that there are always side effects, you just have to pick your poison.
With photovoltaic systems you have the nasty chemicals currently associated with manufacture, with wind power you have what some people consider noise and landscape pollution, along with bird strike problems, although this problem is probably over hyped with newer windmill designs.
There is, as they say, no free lunch.
True. What we need is something like Trantor - use the (negative) heat gradient from deep in the earth instead of the gradient in the oceans. Of course, we'll have to do more research drilling, but we're already getting close to the mantle!
--LWM
ps - no "think of the earthworms", please.
First of all, the turbines killing birds myth is getting really tired. Buildings kill birds too, but we seem to be building those. Properly located wind farms do not kill significant numbers of birds. This myth comes from the fact that one particular wind farm was placed directly in a valley that birds migrated through, giving them no choice but to go through and risk being killed. There's tons of other wind farm installations which show birds who have a choice to go around them, do go around them.
And what do you think that solar energy is going to do if you don't turn it into electicity? The sun already raises the temperature last I checked.
No, but it does derive it's power from heavy elements that were created by the explosions of older stars.
"Prefiero morir de pie que vivir siempre arrodillado!"
A very important point to remember is that we will use an increasing amount of energy for the forseable future and that energy will be generated somehow. Coal is the default power technology. Every time a wind / nuclear / tidal / etc power plant doesn't get built another coal plant is built instead. So the question isn't "Is there an environmental impact from this power source?" - we know that answer, there always is - the question is "Is this better than coal?".
-- The act of censorship is always worse than whatever is being censored. Always.
No, even photovoltaic solar panels aren't passive. They prevent energy that would reaching the ground from doing so, altering the energy balance there. In short there is no form of energy that we can extract from nature that doesn't alter in some way (large or small) the natural energy flows and balance in nature.
I'd hardly call this "debunking". I happen to know David Battisti, and I think he's a good and credible atmospheric circulation researcher. On the other hand, plenty of other good and credible oceanographic circulation researchers I know would refute this, and have done extensive work on the amount of heat transported by the Gulf Stream, and its role in sustaining thermohaline circulation and associated climate effects. A press release about paper maketh noth scientific truth.
Not only that, but even if the Gulf Stream is not the primary deliverer of heat to northern Europe, the 20-line press release you cited does not claim that Europe's climate will not be affected by a change in thermohaline circulation.
So if you're searching for a thin vine to cling to the increasingly untenable view that carbon-loading of the atmosphere is not a major problem, better not grab too hard on this one.
I guess I am being punished by my mechanical engineering background.
It is possible that there is some good information on this site (somewhere), but quite frankly I do not know what you would want to waste time separating the real information from the quackery.
----- There are two kinds of people in this world, my friend; those with loaded guns, and those who dig.
Fission reactors, our only current form of nuclear power, split uranium nuclei into smaller fragments and thereby release energy. However, to form the uranium atom in the first place from smaller constituents therefore required energy. This energy is thought to have come from a supernova ~6 billion years ago, predating the formation of the solar system. Thus current reactors are, by some (possibly warped!) definition, still using fossilized "solar" power. The same can also be said of geothermal which relies mainly on natural decay of nuclei formed by the same supernova.
Only if we ever get fusion reactors working then we really say that we are no longer reliant on solar based power...and that's because we will have made our own mini-sun.
Won't somebody please think of the Balrogs!
Gosh, I am disappointed in the quality of nerds these days. Ever heard of the back of an envelope? For god's sake, units of energy are defined by how much they heat water, so it's not hard to figure this one out.
Projection from http://www.eia.doe.gov/oiaf/ieo/world.html is that the world will use 645 quadrillion BTUs of energy per year in 2025. If we assume this all comes from the ocean at 100% efficiency, this would be enough to raise a patch of water, 100m deep by 1024km on a side, by 1 degree C. Insignificant next to the whole ocean? sure. But certainly significant compared to local or even regional climate variation! (not that hydrocarbons aren't worse, or that this can't be spread out but hey, now all the slashdot blather can be vaguely informed. sheesh).
Also, the tidal force actually also gives energy to the moon, so its orbit is slowly getting bigger. Only a few cm per year, but there it is.