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I'll grant you that, despite having relatively high levels of THD, the inverter models you both referenced are in the 90% efficiency range and are qualified to be connected to the utility grid as synchronous inverters. However, that changes this thread premise and conclusions by "mouse nuts".

--Boot Hill

Note that I never said my system would pay for itself any time soon. I'd get better interest in a bank savings account.

That being said, I still favor solar power, not as a whole solution, but as part of a suit of solutions.

Further improvements in the whole system tend towards it becoming a larger part of the energy equation.

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.