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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."
Just like hydro power, this one has the problem of disrupting the environment, albeit a very local environment. By moving water against the normal gradient, you will warm up water that's supposed to be cold, and cool off water that's supposed to be warm. I could imagine plankton blooms and oxygen depletion, among other side effects.
Passive solar collection (photovoltaic and otherwise) and wind power are really the only truly "green" power sources.
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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"!!!
Nice to see concepts popularized (though hardly invented) by Sid Meier's Alpha Centauri being realized, considering this is basically like a Thermocline Transducer.
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?
'Has developed'? How about 'is developing'?
I mean, in the last year, I've read about thermal stacks, hydrogen generation using thermal power, horizontally-oriented wind turbines, and probably some other alternative power methods. They're all great ideas, with great possibility, but the summary for every one reads like a sales pitch.
AC: Only on slashdot... could the sentence "My hovercraft is full of eels." be moderated "+4, Insightful
It's difficult to even quantify the amount of energy stored in the ocean. You know that oft-quoted tidbit of how a single large hurricane has, by far, more energy than all of the energy that would be produced from all of the nuclear arsenols in the world? That hurricane receives 99% of its energy from the sea, and at most, it lowers the local ocean by under a degree (and most of that isn't because of draining energy, but rather, from stirring up colder water from down below.)
I'm sure someone can go into the math of exactly how much energy the ocean contains by multiplying water's heat capacity to the amount of water in the oean, but I'm too lazy to do that. The fact of the matter is that there is more energy in the ocean than you can possibly imagine, and that even if we changed our entire electrical grid to run off of the ocean energy, it would barely have an effect, even locally.
In fact I think there are three sources of energy on earth:
Solar
Nuclear
Stored friction (hot core)
everything is a stored form of something else, and the three above are a stored form of the big bang.
-nB
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With this in mind, is it really wise to start monkeying with the thermal gradient of the oceans at the equator?
Do the math. The entire world's energy budget isn't enough to make even a microscopic change in the thermal gradients of the ocean.
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I think you forgot gravitational (I.e, the moon's influence on the ocean tides)
I've been reading about this since the 70s. It's a great idea and I can't understand why no one has built a prototype yet. Most of the systems I read about proposed using something like amonia since it was dealing with a temperature difference rather than high temperatures. Some chemicals like amonia boil at very low temperatures. They don't produce the power steam does but it's a stable source. Deep ocean temperatures are near freezing where as surface temperatures can be 40 to 50 degrees higher in the same area. Some have complained about cooling surface water. The ocean is a mighty big heat sink and it's doubtful plants that are spread out would have much affect. In truth it might help offset some of the surface warming caused by global warming. I'm not sure enough plants could be built that would drop ocean surface temperature one degree. Temperatures have already raised that much in the last 100 years.
The problem here is the huge quantity of thermal energy that needs to be exchanged for a small amount of useful work. To generate work between a 80 degree f source and a 50 degree f sink the best you can do is around 7 percent efficiency.
Because dolphins happen to live closer to the surface of the ocean than the bottom, along with the vast majority of sea life. And waves are plentiful near the shore, where they would be seen by people and interfere with ocean traffic.
This could be built out of sight and away from the vast majority of living sea creatures. You have to build it where the ocean is very deep, namely, away from where most people live.
The radical sect of Islam would either see you dead or "reverted" to Islam.
Waves depend on things like wind and tides to work. Winds change with the weather, and tides change all the time (at least tides are regular). Whereas it's *always* possible to get a 20degree heat gradient.
Besides, if you put your heatsinks below the surface of the water, you don't have to worry so much about storms and such.
--LWM
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.
Under-ocean electric generation methods are doomed to be radically costly to maintain. Damn, ever see what salt water does to most machines over time? Not pretty.
Horns are really just a broken halo.
Perhaps it's not a good idea, but if you justify it as cooling down oceans we've already heated up, then it's completely consistent with human history as it relates to science: No matter what we've screwed up, we always think we are, at the moment of thought, smart enough to fix the new problem.
for instance:
global warmng isn't really an issue. Truth be told we don't know what the hell is happening to the enviorment.
I really, really doubt that this thing is practical. Organic Rankine Cycle Turbines (which are proposed) are very expensive to operate on dry land, as has been shown by research into solar thermal power in California. At least in those cases the efficiency was around 20%. The best they can hope for with OTEC is about 1.5% efficiency. Theoretically they could get 3.25% (Carnot efficiency), but experience with Organic Rankine Cycle Turbines has shown that 300C solar plants (Carnot Efficiency ~50%) only get around 20%, so one could expect to get about 1.25% efficiency out of their OTEC setup.
On top of this, all the equipment must be marine grade (ie., pricey). Power must be transferred to shore. It also must be a functioning ship with all the expense associated with that.
But what makes me most suspect is the claim of making fresh water. Ordinary Rankine Cycle Turbines do produce fresh water via distillation, but the Organic Rankine Cycle is a closed cycle and no fresh water is produced. The only condensation you'll get are hydrocarbons, which are recycled to create more vapour.
You're right, this does have zero emissions in terms of greenhouse gasses, and the production of clean, fresh water as a result of condensation is quite useful. However, as an article that's linked to by the original article notes, there may be consequences that would arise from dumping heat into cold water over the long term. The environmental impacts that can cause some real problems are often the unexpected ones. After all, climate change as a result of global warming wasn't really forseen at the start of the industrial revolution when we started burning a lot of fossil fuels. At that time it would have been basically assumed that the atmosphere was vast enough to hold a virtually unlimited amount of emissions, just as with this process it is being assumed that the deep water can hold a virtually unlimited amount of additional heat.
GET THEM INSIDE THE VAULT!
In this case its survival of the smartest. Maybe the birds around the Altimont Pass are particularly stupid and are doing the rest a favour by removing themselves from the gene pool. If I look at my front window, a quarter mile away is one of the biggest wind turbines I've ever seen. Can't say I've spotted a single bird carcass lying on the ground underneath it.
Personally I don't believe wind turbines kill birds. I call bullshit. The blades just don't turn fast enough. And anyway, birds very quickly get out of the way of fast moving objects. When was the last time you ran over a bird in the road with your car? Drive at 'em as fast as you like. They see you coming and by the time you get there, they've moved.
Why does it matter whether the cycle is natural or not? Even if it did turn out to be a natural variation in climate, it's still going to have exactly the same effect on us as if it were caused by us.
What matters is whether or not the change in the world's weather patterns is going to make life on this planet difficult for us humans, and we don't really need a long historical analysis in order to determine that - we just need the short-term data & some decent climate models. And most of our current models are telling us that we're in deep doodoo and digging a hole deeper every day.
I'm not hearing any plans from our so-called leaders about what we are going to do about it - the loudest voices seem to be saying that we shouldn't do squat because they don't want to pay for it.
Even if we are incapable of changing the actual climate, then we should actually have a plan on how we (humanity) can adapt our lives to accomodate the changing conditions, but as far as I can tell the people with power & money are perfectly content to let the poor get fucked over while they (the well-off) are free to move to wherever is most comfortable to live.
Er, no. I challenge you to go somewhere up north, where there has been visible increases in the rate of ice shelf retreat and glacial calving, and say that global warming isn't really an issue. The world is getting warmer, period.
The question that I think you're alluding to, by "we don't know what the hell is happening to the environment" is that there's still a (somewhat) open debate as to whether the warming is caused by anything human beings did, or if it's part of some greater and not-yet-understood climactic cycle.
However in either situation, there are ongoing non-insigificant temperature increases and ice melt occurring, with resulting desalinization of regional oceans. The evidence for this is widespread and not in dispute by any reputable authority. Regardless of whether this is the result of fossil fuel consumption or "just nature," it's still something we're going to have to deal with the consequences of.
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"All power generating facilities are going to cause environmental damage"
Environmental changes. You can't just assume that those changes are "damage".
How pathetic are you that you follow me from topic to topic and waste all your mod points at once modding me down?