It's astounding what Americans will get excited about. A metal can heats up when it's in sunlight....who would have thought it?

There was a big push a couple of years back, here in Australia under our previous Government, on subsidised solar panels and insulation. It was all around the time of the Copenhagen summit on the end of the world or something. I don't know and don't subscribe to the doomed and dammed notion.  Anyway, I investigated the solar panel issue pretty thoroughly and crunched the numbers to find that the "break-even" point in terms of cost V savings pretty well coincided with the likely life expectancy of the panels.  Apparently, they begin to deteriorate in efficiency fairly soon after they are put into operation and there is a gradual decline until they are no longer viable.

ie: No noticeable net savings in the long term and considerable up front cost. 

Then, as they were winding back the subsidy scheme, the Environment and Energy Minister came out on ABC national radio and said that residential on-roof Solar Electricity was "the most expensive form of electricity generation available". It also creates a whole heap of problems when it is fed back into the grid due to instability.  Why then were they subsidising it? Who knows, but the Green vote has a big pull.  You have to admire those tree huggers for their ability to scare and influence the politicians.

This was for electricity generation. I am however, a convinced and enthusiastic supporter of solar hot water. Although I don't have it on my present house I have lived in houses which had it and will say that it was brilliant.  Here in Australia we have an abundance of powerful sunny conditions and free hot water saves a lot of money. I also had it plumbed into the combustion heater for winter water heating.  The electric boost switch was rarely used at all, in the whole time I owned the house.

As for the Government funded insulation program, it was mismanaged, rorted and ended up causing deaths to several young installers, house fires and the collapse of the industry as it had previously been running.  Many pre-existing viable businesses were dissolved due to the poor implementation of what could have been a good project.

My m8 when he lived in gran canaria used similar principle to heat his swimming pool using long lengths of water filled black hosing snaked out on top of his garage roof. Worked a dream. Every hour or so a 45 gallon drum worth of 80 deg C water would come into his pool from it.

Out here with temps reaching near 50'C in some places recently, it is possible to fry eggs on a shovel.  I'd imagine it would be a bit tricky to cook a naan or a good madras though.