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8	“Sure, solar power is expensive, but isn't it just a one time expense, basically?...So solar power may cost a lot now, but it pays for itself in the future and you reap those savings year after year?”

Maybe you could point out those savings "you reap year after year"...

The Inefficiencies of Solar Power
(Based upon a horizontal PV array located at
the average continental U.S. latitude of 38º.)

ref.	source	loss (%)	power (per m²)
1.	Solar flux	-	1,368 W
2.	Atmospheric losses	45	752 W
3.	Night times losses	50	376 W
4.	Solar angle losses	50	188 W
5.	Cell conversion losses	88	22.6 W
6.	DC®AC inverter losses	10	20.3 W
7.	Net efficiency		1.5%
8.	Net energy (per m² per day)		0.5 kWh
9.	Value of energy (per m² per day)		4.3 ¢
10.	Solar panel cost (per m²)		$530
11.	Payback period		33 years

Notes:

1.	Above the atmosphere. Compare to solar constant.
2.	Loss = atmos. absorp. + atmos. reflect. + cloud absorp. + cloud reflect. See additional references: 1, 2, 3,
3.	Necessary for calculating average daily value of energy production.
4.	Effect of solar angle on efficiency. Line 4 equals 4.5kWh per day. Compare to U.S. Average Daily Solar Radiation.
5.	Shell SQ175-PC, including specified de-rating for cell temperature and irradiance level.
6.	5kW modular, certified, grid-interactive, inverter.
7.	Line 6 divided by line 1.
8.	Line 6 times 86,400 and divided by 3.6E6.
9.	From 2004 DOE stats for average U.S. residential price.
10.	Shell SQ175-PC solar panel, $699, 1.32m² area.
11.	Exclusive of installation, inverter, interest, etc.

--Boot Hill

There are certain assumptions that are not accurate in all cases. For instance, in the part of PA where I live, power is about 10 cents per kWh, not 8.6 cents. And the pricing of the panel, listed at $699, can be much less if you are a careful shopper. But I do agree that in general the payback is not there yet.

Yes but what is energy independence worth to a homeowner subject to shocks in terms of foriegn and domestic energy price jumps. To spend a couple of thousand bucks for a low maintenance energy production system that may not pay for itself for many years may seem foolish, but if you have energy when others don't due to price hikes, wars or natural disasters, the potential costs are insignificant compared to the freedom and flexibility such a system gives a home-owner!

Actually, your figure won't work if Dr. Alvin Marks' Lumeloid (solar cell on a roll) becomes a reality. Lumeloid, a photovoltaic film, has a theoretical conversion efficiency of 72-84% and can cost as little as $1/m2. The table you cited only used a conversion efficiency of 12% (88% cell converison loss). Even if one were to assume a sold frame will increase Lumeloid's cost to $10/sq meter; the payback ratio will definitely be positive within the first year alone even if one prices it at only 3 or 4 cents/kWh

Here are my figures for an equatorial site:

Solar Intensity above the Atmosphere 1,370 W/m2
Loss of energy from passing through the atmosphere
Absorbed by atmosphere (20%) 274.0
Scattered (6%) 82.2
Reflected back into space by clouds (20%) 274.0
Reflected back into space by earth’s surface (4%) 54.8
Total loss (50%) 685.0

Remaining insolation hitting the earth’s surface (50%) 685.0
Insolation for solar power purposes (54%) 739.8

P.S. I did a Project Proposal for Lumeloid but for a 1,5 and 20 sq km solar power plant located in Yuma (32.67 degrees) latitude. My studies have shown a Lumeloid power plant of 1 sq km in Yuma can break even within two years even if selling the power to utilities for only 2 cents/kWh.

Nice table, but it doesn't take into account that solar cells degrade and the energy output eventually drops to the point where they have to be replaced - most likely every ten years or so, so there is NEVER and time where you get your costs back.