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Tidal Power a Reality
updog writes "Here's an interesting story about a city in Norway using an underwater
turbine to generate electricity. It doesn't produce much power (300kW) but maybe it'll pave the way for these types of power plants. Maybe one under the Golden Gate someday??"
For those of you that don't know, this is something that author Marshall T. Savage proposed in his "Millenium Project", a book in which he set out a plan for how human beings can colonize the universe. Though I think he's far-fetched, the plan to build world-wide floating cities on top of hydrolical power-generating hexagons is feasible.
Check out information on the Millenial Project here or here.
This also brings me to the interesting Free State project, mentioned on Libertarian Candidate Rachel Mill's Homepage which links to The Free State Project. Interestingly, Rachel Mills decided to raise money for her run for office by selling pushup calendars of the female Libertarian candidates. Yep, Libertarians stand up for your rights and (some of them) do it while looking good too. A much better way to raise money than what the corrupt Democrats and Republicans do, which is by accepting tacit bribes from special interest groups.
social sciences can never use experience to verify their statemen
What kind of environmental concerns will be raised about this? I remember the project in Canada or whatever (name slips me right now, some big bay) that was being considered for damming to produce tidal power. However, because of the amount of water involved, it would change water levels all over the world.
Um, no.
The tide is actually a huge double-lobed bulge around the whole planet. To grossly simplify, two quarters of the planet have higher than normal water levels, and the other two have lower than normal.
Even if you built dams around all continents, the amount of water you'd trap would be about 0.1% of the surface area of the ocean, for a sea level change of one thousandth the height of the _dam_ (not the ocean). This is truly miniscule.
The real problem with dams is that when you build one, you flood a large region of land behind it. For areas that wouldn't normally be flooded (e.g. with hydroelectric projects), this causes environmental upset, and leaches all sorts of crud out of the rocks and soil far faster than rain leaching would (so you get a large spike in, say, mercury levels for a few years). This is unpopular.
Tidal areas are already flooded regularly, so the effects are far less drastic there. All you end up doing is making it very difficult for marine creatures to reach the shore (bad if you built in something like a turtle breeding ground), and change with the timing of the tide cycle (you need to drain the dam when the ocean is near the low mark and fill it when it's near the high mark to generate power, meaning a much more abrubt change in water level for the beach).
Not sure if this is part of the project you're refering to, but Nova Scotia Power uses the tides of the Bay of Fundy to generate power... page also gives a BRIEF overview of how tidal power works for those interested - but not THAT interested :)
Actually, It would.
Friction between the Earth and water, drags the tidal bulge a little bit ahead of the moon. This, in turn, cuases an unbalanced pull that slows the Earth's rotation and transfers angular momemtum to the Moon.
The result is that the moon moves about 3.8cm further form the Earth every year and the Earth's Day increases by about 1.5 ms per century.
Tidal power plants would increase this drag and slighty speed up this process, (very, very very slightly, not enough to make much of a noticealbe difference, but a difference none the same.)
In effect, tidal power plants derive their energy from the difference between the Earth's period of rotation and the Moon's orbital period. Pulling extra energy from this system slighty hastens the day when the Earth eternally shows only one face to the Moon.(Not enough to worry about, though)
Isn't it strange that the publisher of Penthouse (Bob Guccione) is the only celebrity to ever endorse nuclear fusion, which is the only viable solution we are ever going to have to our insatiable lust for energy?
Funding for nuclear fusion is scarce, probably due to energy companies' opposition to anything that could possibly mean free energy.
Actually, this is wrong on pretty much all counts.
Fusion reactors are very big, and very expensive. This is why funding for fusion projects tends to get cut when economic belts are tightened. This is also why fusion energy will never be free - your plant has yearly costs (maintenance, and the amortized cost of building the plant over a reasonable payback window). These costs are passed directly on to the consumer, in the form of a nonzero price for electricity. The same happens with things like hydroelectric and fission power - the cost of the fuel required is low (or zero, for hydroelectric). You're paying for the plant/dam.
Lastly, the fact that electricity never will be free (due to the cost of facilities for producing/distributing it) means that a) there will be no magic free-energy solution, and b) our lust for energy had damned well *better* be sated, because otherwise we'll be awfully disappointed when we find out there isn't a free (beer) supply.
Oh, and if anything, I'd expect the big fossil fuel companies to be the strongest _supporters_ of alternative power sources. They're on top of the market now, and as soon as fossil fuel supplies wane and prices go up (or taxes on fossil fuel emissions rise), they'll want to be right there ready to sell the alternatives.
The process for creating a fusion reactor has been mapped out since the 1970s -- however, it would require the equivalent of 7 fission reactors to start the reaction before it can sustain itself, and materials including a very large 3-foot thick shield of lithium.
Startup power isn't really an issue. The real problem is that producing fusion isn't as simple as building a big donut and watching it go. Fusion ignition is harder than anyone thought 30 years ago, and the engineering problems involved with building a useful fusion reactor are orders of magnitude harder that we'd thought as well. Progress is (slowly) being made, but it's going to be a while, and it's *not* going to be cheap.
In summary, I'd suggest doing a bit more reading about fusion and power generation in general before extolling it's virtues as a cure-all.