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The Solar constant is 1,366 watts per square meter. I have trouble envisioning metric units, so let's say you get a 4' x 8' solar panel. Ideal energy impingement of the panel would be (1366W/m^2)(32 ft^2)(2.54/100)^2(m^2/in^2)(144 in^2/ft^2) = 4,061 W when the panel is facing the sun perfectly. Even if you track the sun the power received by your panel will vary sinusoidally due to atmospheric attenuation, so the average power you get in the daytime is 0.6366*4,061 = 2,585 W. I'm unsure about the efficiency of solar panels, but I suspect it is no greater than 50%, taking you down to 1,293 W. Motor-generator inverters are capable of delivering up to 94% efficiency, but electronic inverters are limited to a maximum efficiency of 50%. Now you're down to 646 W average power, with a peak of no more than 1,015 W, or about 1 KW per panel. You need to feed the output of the solar panel(s) into a battery (bank) to store up energy for night use, dropping you to an average of 323 W per panel., or fudging a little bit, 3 A. at 110 V. That's enough to power a TV, a computer, and maybe 2 60 W lamps. Sizing the system up to be able to handle your furnace fan and refrigerator will require at least 10 panels to prevent repeated motor or compressor burnout. That's an area maybe 20 ft x 16 ft. The bank of panels or each indivudual panel must be on an equatorial mount (like a telescope) so you can track the sun not only daily, but throughout the year, although annual tracking can be dispensed with if you mount the panels ar an angle of (Latitude - 23.5). If you want to dispense with tracking altogether, multiply the number of panels by at least π/2. Remember, too, that these calculations are only good for clear days. Cloud cover can render solar panels totally ineffective.

2007-02-06 09:37:47 · answer #1 · answered by Helmut 7 · 0 0

Very Effective if you use it right.

When the electric goes off my system auto switches to the solar back up system and I never know the city power went down. But if you are grid tie only you will lose power the second the city power goes off line.

Where I live the power goes off seems like once or twice a month so my solar electric system payed for it's self many times over. Just simply because I had electric.

2007-02-06 15:12:26 · answer #2 · answered by Don K 5 · 0 0

If you're doing it to save money, then it is effective, but only if you, or the company installing it, figures out exactly how much energy you need to generate on a monthly basis. When solar energy is used in your home, your meter runs backwards, so you don't have to pay the electric company for electricity used. So if you have too much power coming in, you're not going to use it all, but if you don't have enough, then you will still have to pay a portion of your electricity bill.

if you're doing it save preserve energy on a larger scale, for the benefit of the world, then it's a nice effort...but it's not quite there yet. It costs so much energy and money to produce the solar panels that the ends usually don't justify the means...

2007-02-06 08:30:10 · answer #3 · answered by Sgt. Pepper 5 · 0 0

Popular Mechanics has been doing a series of articles about this with a family that lives too far from the power grid to buy electricity. Basically they have concluded that it would take a very long time (over 25 years of electric bills) to recoup the investment. If you can get your hands on it, check out the January 2007 issue of Popular Mechanics.

2007-02-06 08:27:05 · answer #4 · answered by boogie2510 3 · 1 0

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2017-02-01 12:20:06 · answer #5 · answered by ? 3 · 0 0

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