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Well the efficiency is more than 15% higher than you claimed. And your claim was absolute. No room for any other thought.

From my first post on I never claimed solar electric was a good economic alternative as of today. I did say it was improving.

Things change. Just like the improved inverter performance you so refused to accept. New thin film PV technology is driving the price down as we speak. It uses much less material and energy to manufacture.

It is not unreasonable to think that PV cell costs could drop to a fraction of what they cost today with new technology and high volumes. Even without any improvements in PV efficiency (conversion efficiency only reduces the area for a given output power not necessarily the cost) a panel that puts out 100 W that cost $100 (the panel you said currently costs $700) with an inverter that costs $1 a Watt would pay for itself in 5 to 8 years at my home at current California electricity rates.

To make the demand that solar energy has to provide 100% of our energy demand or its useless is just plain BS. Using 50% percent of the roof area of my new home (submit to city next week) could provide 18 kW-h a day at 10 W per m^2 with 8 hour average sun availability. That would put a big tent in my electric bill. So the real issue to make it practical is PV cell cost. It needs to improve at least 5 to 1 to be cost effective for use at one’s home. That 5 to 1 cost improvement lessens as utility electricity costs increase. I don’t think it is improbable at some point in the future they will converge.

Here's one more photon...

DB says: "I never claimed solar electric was a good economic alternative as of today."

Economics is the fundamental criteria for selecting a method of power generation. Every thing else is just sophistry.

DB says: "Just like the improved inverter performance you so refused to accept."

Incorrect, the only thing we've been arguing is whether or not those higher efficiency units were qualified for connection to the public utility grid, not whether those higher efficiency units existed.

DB says: "New thin film PV technology is driving the price down as we speak."

It is??? Somebody must have forgotten to pass that piece of wisdom on to the manufacturers. Here's some typical data from Shell Solar, one of the biggest producers of solar PV arrays.

	SP150 standard technology	ST40 Thin Film
$/watt	$4.62	$6.10
watts/m²	114 watts	94 watts
wattage warranty	25 years	10 years
Temp loss	.45%/ºC	.60%/ºC

DB says: "To make the demand that solar energy has to provide 100% of our energy demand or its useless is just plain BS."

I'm not making that claim, but it is by examining the economies of scale that the absurdity of solar power can best be seen.

--Boot Hill

I have a friend here at work that also just loves solar power, not that I don't I just like wind better, that is always pointing out that after 30 years they are still working. Solar panels last a long long time once you make the initial investment.

This person bought 4 55 watt panels for a thousand bucks. They have been in boxes in his garage for 3 or 4 years because he doesn't want to cut down the trees necessary to get the sun to the panels. He keeps talking about buying a Bergey windmill too.

He almost cried when I told him this country uses 3 quads per year which amounts to about 10 mwhr per person per year.