In Switzerland, they have a lovely solar power generation station on Mount Soleil. Here's what it looks like.
Here's the story.
The 110 silicon panels, standing in a field on a hilltop, have a total area of about 4,500 square meters (nearly 50,000 square feet). They are tilted at the best angle to catch the winter sun. The plant, which produces nearly 600,000 KWh annually, is one of the biggest in Europe.Using 2003 data, San Diego consumes 18,397 GWh of electricity per year. Note the unit differences. Consumption is in Gigawatt hours and production is in Kilowatt hours. If you used solar power to supply San Diego, you would need about 55 square miles of these panels, not accounting for the power lost in transmission lines or in the motors needed to track the sun.
Of course, San Diego would only be able to use the power during the day. At night, you'd be hosed. If you wanted to replace Southern California Edison, too, you're looking at covering another 245 square miles. Throw in the other Southern California electricity giant, Pacific Gas and Electric and you add 240 square miles of solar panels. That comes out to be around 540 square miles covered in solar panels, not including the roads needed to install and service the units nor the losses mentioned before. I imagine the costs of installing 540 square miles of solar cells in the middle of the desert would be trivial, right? I mean, how hard is it to get tens of thousands of workers and their equipment out to a piece of flat land? Criminy, if the Egyptians could do it, so can we!
Sounds like a plan! Alternative energy - yes, we can!
3 comments:
You are being far too pessimistic. Solar was never intended to completely replace current power plants. By stating the proposition as an all or nothing issue, you're just creating a straw man argument.
The best use of the photovoltaic generation of electricity is supplement an existing power system in order to avoid having to build additional plants. The peak energy demand is during the late afternoon, the exact time that solar would be producing its peak output. One could, in principle place a set of panels on their house that would offset between 60% to 90% of their daily use. Businesses could adopt a similar strategy by lining their warehouse roofs with photovoltaic cells. Most homes in southern California, as well as the majority of homes in the south and central west have no shade trees blocking the sun to the roof, therefore fixed panels in these climates can generate enough electricity to offset a large portion of daily use as well as provide shade to the roof.
The downside isn't the technology, but rather the cost. Either the efficiency of the cells must double or the cost drop in half to make it a commercially viable option with out either tax credits or subsidies. That said, this isn't really a fair comparison because the oil and coal industries receive huge government subsidies that rig the price in their favor. And even now in areas with high utility rates such as the Bay Area of California or Boulder Colorado, a home photovoltaic system will pay itself off in about 15-20 years because of state subsidies.
So suppose 10% of homes had systems that cover 60% of their day time power demand ( which can be up to 2/3 of the daily demand depending on lifestyle ) that works out to be roughly 3-4% of the total household demand. That is the difference between having and not having a brownout during a summer heat wave.
You are also seeing a movement of big box stores ( such as WalMart and Costco ) to install photovoltaic systems on their warehouses. The fact that they are willing to try it suggests that the proposition is near break even for them.
Lastly, lets address your primary myth - that at night you're out of luck. There are two very simple ways to store any additionally generated power.
The first is only an option if you have the geography that supports the hydroelectric generation of power. Simply pump water back behind a dam when there is excess electricity. This is already used extensively in the upper mid-west and the east. At night, when there is excess power from the coal fired plants, they pump water back behind local dams and release it again the next day. Since most conventual power plants can't throttle generation backward and forward with demand, converting the power into potential energy allows it to be used later.
The second approach to store excess power is to crack water for hydrogen. The hydrogen can be stored and later combusted on demand without producing any emissions. This approach has also been suggested for intermittent power generation from sources such as wind.
Actually, your energy storage methods simply compound the problem as they are all inefficient themselves. That means you'd need even more solar cells to store the power for the night as it would not be anything like a 1-1 energy conversion.
When we built our house here in San Diego, we looked into solar power on the roof. Even with big subsidies from the government, it didn't make any sense at all. Solar hot water was even worse. Our plumber said he was removing far more than he was installing.
I agree that it has applications as a supplement, but the scale of the problem is so vast that it's hard to see it being anything more than a symbol.
As for subsidies for coal and oil, man, that's a stretch. We were offered direct rebates for solar hot water and solar electricity. We were offered rebates for anything that reduced electricity consumption. The farm bill, year after year, pours gobs of cash down the ethanol rat hole.
Core taps. That's my solution. Direct geothermal heating of water to drive turbines. It's scalable and available 24-7. The technological hurdles are many, but we might as well get started now. This solar and wind junk isn't going to save us.
Kelly / KT Let's see..
First solar is ideal in that it produces power when we generally want it (during the day), as a supplement. The energy cost of producing the cells and the economic costs of installing and operating them are significant impediments keeping solar as demonstration vice viable alternative.
Sure pumping water, or producing hydrogen is a simple and relatively easy way to store excess daytime power, for use later.
Wind is too spotty, but certainly let's use it where possible.
Tides and geothermal are even more so.
But the bottom line is that the only practical method today that will significantly reduce the dependence on oil/coal is nuclear.
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