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Future Looks Bright for Large Scale Solar Farms
Hugh Pickens writes "The economist reports that Concentrating Solar Power (CSP) systems that capture and focus the sun's rays to heat a working fluid and drive a turbine, are making a comeback. Although the world's largest solar farm was built over twenty years ago, until recently no new plants have been built. Now with the combination of federal energy credits, the enactment of renewable energy standards in many states, and public antipathy to coal fired power plant, the first such plant to be built in decades started providing 64 megawatts of electricity to Las Vegas this summer. Electricity from the Nevada plant costs an estimated 17 cents per kilowatt hour (kWh), but projections suggest that CSP power could fall to below ten cents per kWh as the technology improves. Coal power costs just 2-3 cents per kWh but that will likely rise if regulation eventually factors in the environmental costs of the carbon coal produces."
There's enough energy available from uranium that $724/pound (2006 dollars, according to the inflation calculator at http://www.westegg.com/inflation/) would not be a show-stopper.
Solar Tower - Large Scale Renewable Energy Animation
also take a look at this discovery channel video - @ about 3mins in
Absolutely. However, we have, AFAIK, around 500 years of coal reserves at our current rate of usage. We just need to figure out a better way to mine it. Natural gas availability is declining, with rising dependence on foreign imports of LNG. New nuclear technologies are important considerations, but not for an Executive Branch of oil men. Unfortunately, if the pendulum swings too far the other direction, NIMBYs (Not In My Back Yard) and BANANAs (Build Absolutely Nothing Anywhere Near Anything) will put a stop to anything nuclear because it's scary.
I don't understand where they get the number of 17 cents per kilowatt hour of production from this solar plant, unless it's ridiculously expensive to build. Solar, like wind and hydro, which are really just solar plants of a different nature, are mostly capital cost to construct, then operations cost (minimal) and maintenance down the line. Construction costs are commonly amortized over 20 years, so .17/kW, declining to .10/kW seems expensive.
The Spoon
Updated 6/28/2011
No they don't. Coal produces the most carbon-dioxide of any major fuel. This is elementary chemistry, because coal is mostly carbon.
They're also measuring KWh at the generating plant, and ignoring transmission costs. I suspect, however, that most of the electricity from the Las Vegas plant is being used locally. Doing that with a coal plant would mean situating the coal plant near the use site rather than near the coal mine, and would result in, among other things, a vastly increased cost / KWh, because the coal would be much more expensive after being transported.
Still, coal may well currently be cheaper under current laws and regulations. As I understand transmission losses for electricity don't amount to more than 50% of the energy, and it's a LOT cheaper to maintain the distribution system than to transport the coal. (And you might need to maintain that system anyway for other reasons. So perhaps it wouldn't be fair to include the cost of that system into the cost of coal powered electric plants.)
Nothing is free. You need to weigh the costs and calculate the relationships. Coal puts excess carbon into the air...that's a real cost, even if current laws don't assign a monetary figure to it. As such, coal is to be avoided when possible...but not without limit. Ideally there would be a dollar figure attached to coal (and gas, and gasoline, and...) and the proceeds used to repay those damaged by the effects. That's ideally, and probably impossible to manage. One can't even reasonably assign the effects of, say, any one hurricane to an particular emission of CO2. Rising sea levels are a bit less controversial...now, before they've affected anyone powerful enough to demand payment. They won't remain so. (The law of gravity would be thrown into doubt if there were a commercial interest involved." -- H.L. Mencken)
I think we've pushed this "anyone can grow up to be president" thing too far.
I think the most promising future energy sources, beginning with the best, are. . .
1. Aneutronic fusion / IEC Polywell reactors. If this works -- as seems likely, based on experimental results thus far -- it could begin displacing *all* other forms of power generation within 15 years. The potential is mind-boggling. This could make coal, fission, natural gas, wind, and the majority of solar power and petroleum fuels hopelessly obsolete. Rapidly.
2. Enhanced geothermal. According to a study from MIT, a relatively small R&D investment could open up enhanced geothermal energy production, at competitive costs, over wide geographical areas, including large parts of the USA. It could scale to meet a very large portion of electrical demand. An enhanced geothermal plant is conceptually similar to a nuclear plant, except that the atomic pile is safely tucked away under the earth's crust.
3. Nuclear fission. If fusion doesn't work out, there's good old fission, and you can build it anywhere, even places where enhanced geothermal won't work. We've learned a fair bit about designing and managing fission reactors, but very little has been put into practice in the USA since we haven't broken ground on any new nuclear plants for several decades. We need to start building *now* just to hold our ground as aging plants come up for decommissioning.
4. Solar. It's intermittent, expensive, and requires large amounts of land. And yet, the hype around solar is scary. Nuclear and geothermal have so many practical advantages, I have a hard time imagining solar providing most of the world's energy -- something all the faithful sun-worshippers expect. Still and all. . . Solar technology is being researched, progress is being made, and there's no question it will work at some price level. It may be useful for rooftop systems and assisting peak power demand, at the very least.
5. Biofuels. This is an inefficient method of gathering solar energy, and it competes with food production for the same resources. Realistically, we're not going to power our whole industrial society off this stuff. However, it does produce concentrated liquid fuels, which are highly useful for certain tasks. There will probably be some kind of long-term role for biofuels -- especially if we can get away from food crops and move to cellulose or algae.
It is kind of deceptive to compare a new solar plant (built today) with an old coal plant. The correct comparision is with new coal capacity which may come in closer to $0.04/kWh. With carbon capture and sequestration, $0.08/kWh might be expected. http://www.sciencedaily.com/releases/2007/05/070504151722.htm. Further, at present, solar competes with gas rather than coal because gas is used to meet peak demand. Gas costs less for construction than either coal or solar but it has volitile are rising fuel costs owing to declining production in North America. Over the long term, $0.15/kWh probably compares favorably with gas. Several recent studies have also noticed that coal energy (though not volume) production is declining in the US owing to substitution of lower grades of coal: http://mdsolar.blogspot.com/2007/05/three-cornered-ghost.html. This video on the coal resource is even more startling: http://www.youtube.com/watch?v=aTUcxYdMmj4. If, within the lifetime of the new solar power plant, coal becomes scarce as gas is already doing, then the cost of power from the solar plant will be quite competitive. It is not that we lack coal but rather that we have begun to exhaust the coal that is cheap to mine. This is why salvage operations like the one that led to the disaster in Utah are becoming more common. Higher coal prices make these marginal operations more economical.
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Rent solar power for your home: http://mdsolar.blogspot.com/2007/01/slashdot-users-selling-solar.html