Underwater Ocean Kites To Harvest Tidal Energy 203
eldavojohn writes "A Swedish startup has acquired funding for beginning scale model trials of underwater kites, which would be secured to a turbine to harness tidal energy for power. The company reports that the kite device allows the attached turbine to harvest energy at 10 times the speed of the actual tidal current. With a 12-meter wingspan on the kite, the company says they could harvest 500 kilowatts while it's operational. This novel new design is one of many in which a startup or university hope to turn the ocean into a renewable energy source."
sweet (Score:5, Insightful)
now whales can enjoy the "renewable revolution" like migratory birds and bats do with windmills.
Stupid question, but one that's always bugged me.. (Score:2, Insightful)
Is it possible to exhaust the wind or sea's natural momentum, if there is such a thing? Where does the energy ultimately come from? In other words, is it theoretically possible to have so many wind farms (or, in this case, tide farms) that the atmosphere becomes still?
(captcha: "universe". heh.)
10x the speed? (Score:1, Insightful)
last i checked power wasn't measured in meters/second.
very confused summary.
Another energy-diffuse, capital-intensive system (Score:4, Insightful)
Re:Stupid question, but one that's always bugged m (Score:3, Insightful)
Wind farms are unlikely to stop the wind. Wind is a byproduct of temperature differentials, and as such, as long as the earth isn't exactly the same temperature everywhere all the time, there will be wind.
Tidal farms, on the other hand, I don't know. Tides are due to the difference in gravitational fields at different points on the earth. As such, the tidal energy comes from the Sun's and the moon's gravitational field. Since neither the sun nor the moon are losing mass through the use of tide turbines, what has to change is the distance between the sun, moon and earth. Somehow, I think the time scales on which this becomes a problem are large enough that we'll have entirely different problems then.
The only real problem I can see with tidal turbines is that if they are large enough, they will restrict the flow of the tides, and tides will become less pronounced - which will have an immediate impact on any tidal areas. And since tidal areas and shallow bays are pretty much where the food chains for a lot of marine animals reside, this could be a real problem. But again, it would have to be something on the scale of putting turbines across the entire straight of Gibraltar, and reducing the flow to near zero. Unlikely to happen, but not impossible.
Re:You are overlooking the obvious... (Score:3, Insightful)
No, because the rest of us know that Funny gives no karma, so people choose other options.
Re:What's wrong with it (Score:3, Insightful)
Why, yes, from economic activity derived from burning fossil fuels.
Yes, like essentially everything we do today, no matter if it is something that is trying to get us off of fossil fuels or not. Our economy is based on burning fossil fuels, ergo all economic activity is based on burning fossil fuels.
Spending some of that activity to stop using fossil fuels is, if you consider using fossil fuels bad, what we would call "intelligent".
We should be looking at truly sustainable energy solutions, not scams.
If they produce more energy in their lifetimes than they take to produce -- which, if the system works, they almost certainly will -- then it's not a scam, it's a viable energy source. The more of these we build, the less of our economic activity will be based on fossil fuels, and the problem in the first part of this post will be resolved.
Up-front costs can prevent the development of new technologies, even if in the longer term they are a net positive. Something can be economically viable (which is what it means to have a net positive return on investment) without necessarily being economically practical for a particular entity at a particular time. Subsidies offset this, and get us to the point where we are using fewer fossil fuels faster. This is a good thing.
Different tools for different jobs (Score:3, Insightful)
Then there is the obvious niche filled since the 1970s of small installations off the grid where PV solar etc is competing against internal combustion engines. Then there's things like google's solar in datacentres - effectively just a giant UPS which makes perfect sense if California's electrity supply is as poor as it used to be.