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Solar power in the desert southwest uses about as much land as coal power does when you include the area that is mined on the order of half a century to a century, and uses an order of magnitude less land than the reservoir of a hydroelectric plant. And while desert solar power uses "common" land, hydroelectric plants, by their very nature, use up the most scenic canyonlands and the most sensitive habitats. Really, desert solar power doesn't use much land at all compared to how much it produces.

250 megawatts would move an Aptera 3.1 million miles at 55mph, or 1.8 million miles at 85mph. Assuming no derate factor, of course; factor in that and you get down to 2.7 million @ 55mph / 1.5 million @ 85mph. Of course, if you can directly transfer DC to DC, you can do better than that.

This project sounds very exciting. Anything to ramp up thin film production is good in my book. I find the news coming out very optimistic for solar in the next few years; I see a price collapse and mass adoption on the horizon. Several traditional silicon companies are poised to fix the silicon shortage plaguing solar, 6N silicon thinks that they can drastically cut the price of silicon further (meaning we'd have a *glut* of silicon instead of a shortage), CIGS is claiming ~$1/W, and so on.

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Oh KarenRei, you're usually so good! Watts measure the RATE of energy delivery, not the total AMOUNT of energy. Over a fixed distance (at a fixed speed) the Aptera will us an AMOUNT of energy, so the two cannot be compared.

If the Aptera uses 100 W-h/mile at 55 mph, then it's consuming power at a rate of 55*100= 5500 Watts. If you applied 250 MegaWatts to it (assuming aerodynamic drag is the dominant energy sink and grows as V^3), that much POWER would have your going about 1963 mph.

... of course above the speed of sound (770 mph) all hell breaks lose with drag, so that's not right either.

Of course the energy generated by the array in 1 Hour is 250 MegaWatt-hours, which, (using the 100 W-h/mile number) would move you 2.5 million miles. I assume this is the calculation KarenRei did, but we used different energy consumption numbers.

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I also think that in the coming years solar and wind will get a dramatic price drop , only due to the early buyers and the invention of new easier to produce materials . When you divide a 5500 dollar electrical bill over 12 months you get 458 dollars a month . Seems a little bit high from my city ( new york )

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Your math is wrong!!!LOL

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@Kevin Nugent
That approximate 5500 dollars is the per powered-house cost of the total installation. That cost should be ameliorated over the total lifetime of the solar panels. Not just over one year.

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Kevin, the solar panels will cost $5500 for a lifetime of electricity - typically 25-30 years before output begins to fall off significantly. Assuming 25 years lifetime of the cells, that means a monthly cost of $18. Pretty good, and a LOT lower than the ~$50-$80 I pay a month now.

BTW, $458 electricity bill is not that absurd here in Southern California. My coworker's bill was that high before he made an attempt to reduce it.

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CALIFORNIA- COMMON SENSE FTW. now if only other states (cough- maryland) could follow suit.

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If covering up the desert southwest meant we'd get some shade that would be GREAT! Trust me, it's ~considerably~ larger than a human brain can imagine it to be. And all in all, I'd rather have relatively innocuous panels shading part of otherwise unused land than the results of lots of intensive mining and transporting of coal.

That said, it's of course considerably better to put the power sources right on top of the power consumers and eliminate transmission losses while increasing the resilience and redundancy of the grid. Rooftop solar ftw.

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Why don't we use the 50,000 miles of interstate highway and cover them with solar tunnels ? The environmental impact has already been taken on the area covered by the asphalt so why not use the same area to create a massive solar array across the country ? Why limit the area to the southwest when the whole country could benefit ? Use the printed thin film (like those from NanoSolar and others) to create a lightweight curved roof over the existing interstate. How's that for a solution to finding the land to build an extensive solar electric system for this country ?

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I say we start with structures that are already there and have a purpose (i.e. buildings, houses, car ports, etc) instead of creating new structures over the highways.

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Blah, GoodCheer, you're right -- I left off "hours". That's what I get for not proofreading :P

Dave: "typically 25-30 years before output begins to fall off significantly" -- I've never seen a solar cell that degraded "significantly" in 25-30 years. Perhaps 30% or so. And the degradation slows down, too. And now there are thin film CIGS cells, which in some cases can even *increase* their output with age. They're very resistant to degradation.

Of course, if your payback period is 30 years, you'll never beat interest (on the loan if you have to borrow, or on your investment if you aleady had the money and could have invested it elsewhere).

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Domenick: For the mileage figures above, multiply them by 24, then times the capacity factor (probably 15-25%, depending on the setup), and that's how many miles you'll get out of the Aptera per day.

I had just gone with 250 MWh for the above calcs.

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Umm, here in SoCal we only get about 5 hours of peak solar per day ... not 24 :)

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If your calculations are correct, GoodCheer, that mega-solar installation could power the equivalent 45,454 Apteras at 55 mph simultaneously, on a bright sunny day. Now all we need is a way to get the power to the cars while they are moving...

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How much power output would be possible with Solar Thermal in Mojave dessert for the same sum of money. I know Solarthermal is lowtech but is highly efficient.

Thin film solar cells on roof tops don't seem to be a bad idea too, but they are still quite expensive and don't have good efficiency. If you get an efficiency rate of over 50% with that it would even make sense in Raintown, Germany (also known as Aachen). But it still needs some research.

Furthermore you don't destroy a whole desert with some big 50 MW solarthermal powerplants like Andasol. Andasol needs 1300 m × 1500 m area for this and costs just about 60 million and has a very long lifetime.

And there is a new solar thermal tower powerplant in Jülich which just needs the area of three soccer fields to produce 1,5 Megawatt of power (350 German households) in one of the rainiest regions of Germany.

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"I've always thought that rooftops in the cities where we live would be the ideal location for solar panels."

I would also agree, however there are not enough rooftops to supply 100% of the power and the taller the building the smaller the percentage the rooftop will provide in power, not to mention the other green uses of a roof. You really think a 30 story office or larger can get 100% of its power off its roof? If so I've got some Ocean front property in Arizona to sell you. Not to mention where are you going to put the "green" earthen roof with rain collection and storage if you put solar panels up there? The world population that live in high density city's can not rely 100% on solar without relying on raw land for space to collect the energy. Wo while it may seem as you put it "wrong headed," If you want solar to provide 100 percent of your energy needs you will need raw land, or you will need GREATER urban sprawl to provide the space in roof tops for the panels. Currently you cant have your cake and eat it too you will have to wait 100 yrs or more before that happens.

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I'd suggest covering parking lots with solar panels. For one thing, they'd be easier to install. For another, you'd triple the utility (no pun intended) of the land use because in addition to parking and (daytime) electricity, you provide shade. Keeping cars from heating up reduces mobile air conditioning requirements and the risk of accidents.

The cheapest structures would use poles of two mildly different lengths and cable stays to support a tension surface composed of saddle-shaped elements, each projecting onto the ground as a rectangle. This would reduce efficiency a little bit but also eliminate glare for aircraft passing overhead and generally deliver more aesthetic appeal. Plus, it would be easier to drain rain water in a controlled fashion. However, I'm not sure if printed solar panels can already be stretched into ruled surfaces.

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Large-scale CSP solar power plants in the desert are much more cost-effective than photovoltaics, and they don't harm the environment nearly as much as conventional power sources would. If anything they'd provide a little shade to some of the desert critters. But regardless, I'm happy to see any progress on solar, in whatever form it comes. And I'm proud my state has a "sunny" governor :)

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rgseidl,

I also like the idea of using parking lots, But you run into issues there as well. In the city of Austin, you are required to have trees about every 15 to 30 foot in a typical parking lot. And especially with the new sub chapter E requirements. Also if that parking lot is in a downtown type Environment you wouldn't gather much energy due to the shadows of the surrounding buildings. You'd probably have better chances of catching sun light by placing the panels in the bottom of the Grand Canyon. The parking lot idea is best suited for the Large mall of the 80's that paved over everything and it receives a ton of sun, it would also be good for the Wal-Marts of the world. But again remember the back lash of the 80's pave over everything is the denser requirements for green space and trees. and those items are not the best for solar panels trying to collect sunlight, and frankly for some city's and most environmentalists is non-negotiable.

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Jeez, Arnold's getting old. Still, he looks like he could easily reach out and snap that old guy's neck like a twig.

Anyways, good for them! Bout time someone made use of those empty roof-tops. Also, creates jobs for people to clean up bird-poop off solar cells and scare off birds.

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