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welcome to the 21st century we now have laminate solar panels that are hail and vibration resistant.
http://www.affordable-solar.com/store/solar-panels/uni-solar-laminate-pvl-Series-136-watt
true they rely on plastics, for that flexible production, but technically this tech has existed for quite a while.

The W/sq ft isn't what really interests me - it's the sheer economics. I'll probably prove my lack of caffeination here, so feel free to correct.

BP makes a 200W solar panel, which you can buy for $1100

200W = 0.2kW

0.2kW * 10h/day * 30 days = 60kWh/month

Looking at my electric bill, I pay about $0.10 per kWh.

$0.10/kWh * 60kWh/month = $6/month saved by using the panel.

$1100/$6/month = 183 months or about 15 years before I would break even.

I fail to see why I would ever buy a panel at $5.5/W. It would have to be in the $2/W range before it would be economical for me to consider it. And that's assuming I get the full 200W out of the panel - not a guarantee in the NE of the US. It would probably be half that, averaged over the entire year. That's in the $1/W range.

Are there any panels anywhere near this range? I can see $4/W, and rumors but no real purchasing info on $3/W panels. And, of course, this doesn't count the cost of install and wiring.

An example of a currently available solar panel intended for roofing application is 136 watts, and about 30 would fit on that sample roof, for a total possible 4,080 watts at any given point. Where I am, I can expect an average of 4.5 hours of full production per day, or 18 kwh/day, or 540 kwh/month. That's possible, but would require avoiding high load items like electric cooking, dryers, heating, and cooling. Oh, and the total cost would be $775*30 or $23k, plus installation, charge controller, inverter and storage (batteries).

A much more efficient solar panel, not designed to be applied directly to the roof but which would require a frame mounted on the roof and fit in a 7x7 grid, or 49 panels, could generate 9,800 watts max, or 44kwh/day, or 1,323kwh/month. That's a much more useful number, and might even handle an electric dryer, cooktop, and cooling. Still doubt it could handle heating (excepting heat pump or geothermal). And it would cost $53,900, plus installation, charge controller, inverter, and storage. Amortized over 20 years of service, that's $225/month, which is probably cheaper than your electric bill. Though if you had to take a loan, it would cost $414/month for those 20 years, which is probably more than today's electric bill for that amount of power.

And none of that includes the cost of storage and storage maintenance, which is currently usually battery power.

Both the cost of the panels and the cost of the storage need to come down for the solution to be viable for the average person.

An example of a currently available solar panel intended for roofing application is 136 watts, and about 30 would fit on that sample roof, for a total possible 4,080 watts at any given point. Where I am, I can expect an average of 4.5 hours of full production per day, or 18 kwh/day, or 540 kwh/month. That's possible, but would require avoiding high load items like electric cooking, dryers, heating, and cooling. Oh, and the total cost would be $775*30 or $23k, plus installation, charge controller, inverter and storage (batteries).

A much more efficient solar panel, not designed to be applied directly to the roof but which would require a frame mounted on the roof and fit in a 7x7 grid, or 49 panels, could generate 9,800 watts max, or 44kwh/day, or 1,323kwh/month. That's a much more useful number, and might even handle an electric dryer, cooktop, and cooling. Still doubt it could handle heating (excepting heat pump or geothermal). And it would cost $53,900, plus installation, charge controller, inverter, and storage. Amortized over 20 years of service, that's $225/month, which is probably cheaper than your electric bill. Though if you had to take a loan, it would cost $414/month for those 20 years, which is probably more than today's electric bill for that amount of power.

And none of that includes the cost of storage and storage maintenance, which is currently usually battery power.

Both the cost of the panels and the cost of the storage need to come down for the solution to be viable for the average person.

Sorry, I misunderstood your tone. Google suggests Affordable Solar among others.

Steel and aluminum are not equivalents.

Chemically, sure. In practical terms, however, they're both generally made with high-temperature smelters. And I think you missed my point: iron, steel, and aluminum, despite needing these high-temperature industrial processes, are all fairly cheap. They need energy, but that energy doesn't increase the price that much. And raw silicon metal? Less than a dollar per pound. ( http://minerals.usgs.gov/minerals/pubs/commodity/s ilicon/760397.pdf ) The cost of the silicon in a 120 watt solar cell is probably less than $20. (Evergreen's $600 model weighs 28 lbs. ( http://www.affordable-solar.com/evergreen.ec.120.g d.120.watt.cedar.solar.panel.htm )

So if it's not the raw metal, and clearly it isn't, what stage(s) of turning sand, etc. into a solar cell are expensive? *That's* what I'm trying to figure out. It doesn't seem you know specifically either; your (reasonable) point is generally "if it could be made cheaper, it would have already." And you may be right, I'd just like to know what in the process is the tough point or points.

Not if it takes 3.5 volts and draws 3 watts. A light weight solar cell produces milliamps at around 1 volt. For comparison, I found this 3-watt solar array - it looks like it's about the size of a ping pong table.