It drastically would increase the amount of energy absorbed by the Earth for every square meter installed. That means more energy and “Thermal Pollution”.

Some of the zany suggestions to scale up the size to represent what kinds of areas would be needed to harness an equivalent of the present US electric grid with solar,make the problemplain. The area needed rapidly climbs to areas equivalent to the States of Arizona, Nevada, and New Mexico combined.

Consider trying to apply for an EIS. Raising the temperature by several degrees in these states would likely kill or barbecue all life in those states, as well as create enormous local climate changes. For example: “Explain on your EIS application, how many tens of thousands of species you propose to drive to extinction. Please be specific.”

Solar energy is only 10 or 12% efficient and lots of the heat additionally absorbed, that extra 90% energy is just waste heat, useless to do anything except thermally pollute.

Nuff said.

Nuff said.

They often “disagree” with me when I suggest that they first look at energy efficiency upgrades or reducing consumption, or by signing up for any one of the local utilities “time of use” type plan that saves you money by shifting their usage. The key to saving money on a PV system is to require as small a system as possible.

Of course, if you really want a short term payback, you should invest in solar water heating. Solar water heating is more efficient than PV energy production. Considering that water heating is the second biggest consumer of energy, the savings can be realized in a few years with subsidies.

One piece of technology I’m looking into is the heat pump water heater (HPWH). Instead of using resistors to convert electricity into heat, a heat pump is used to “pump” heat from the surrounding air into the water in the tank. This can cut energy consumption by over half. Other benefits include cooling of the surrounding air by the heat pump, which benefit those that live in a hot climate where the water heater is in a conditioned space, as in my case.

Have you considered using mirrors to increase the light falling on the collection area?

This sort of back-of-envelope calculation is all very interesting, but misses out most of the actual considerations in whether the technology is economically viable. Peak power is not really a very interesting metric, since it is virtually never achieved and never sustained. Barring a major breakthrough, I’m personally not expecting it to make economic sense for a few decades yet. But so long as you don’t try to sell it to people on economic grounds (or saving-the-world), there are all sorts of other reasons why people could legitimately want one.

I took 4 feet as just over 1 meter, and 8 feet as just over 2 meters, to get a little over 2 square meters. Then I applied the same 1 kW/m^2 (which I remember from my college solar engineering course) and a little conservative rounding down, all without actual calculation.

Now the true area of a full 4′x 8′ panel is just under 3 m^2 (2.97 m^2) not 4.26 m^2. So I did underestimate, but not by a factor of over 2. I’d estimate now 400W peak.

But hey, technology is well known to always fail its promises, ain’t it? Just look at the iPhone. Isn’t that a perfect example of how bad can a phone become?

Hogwash. You’re turning your criticisms against vaporware. Technology is really ramping up on solar and other renewables because of the price of the barrel of oil and of coal, which are soaring. Check the investments. They are really betting in any alternative solution. So, it’s not as if we are stuck in the 90s here.

When they announced they were starting to ship production units at the turn of the year, they said they were already sold out through mid-2009, mostly to Germany, where the utilities have to pay ridiculous amounts for solar-generated electricity. So even if all true, it will still be a while before you could get your hands on some.