> Not a good investment. Even worse if the money is borrowed to fund the installation.
I agree that borrowing money is probably a poor choice for this stuff, but that's true in general for depreciating assets in general IMO.
As for "bad investment" -- not so fast. We do not have to convert solar to electric for all applications; there is a real possibility to make solar energy cost-effective when you use it to heat your home.
I'm currently looking at a product by CanSolair -- http://www.cansolair.com/productspecs.php. Their marketing literature says that a 1,000 square foot home can have its temperature maintained with 15 minutes of sunlight per hour.
Back of the napkin time --
According to their spec sheet, it can do up to 10,000 BTU/hr.
I have a 1200 square foot home, two levels (no basement), and an ideal unshaded south-facing wall upon which to put it (it will spill into the bedrooms' hallway) and a realistic outset. So, let's say I can get, on average, 40,000 BTU/day out of it during the heating season, which is Oct 20 - Mar 15 or thereabouts. That's ... 145 days or so, for a total of 5.8 MBTU in the season.
A cord of hardwood is worth about 22 MBTU. I burn 3 to 3.5/yr, at $300/cord. This makes my annual heating cost around $1000.
So, let's see, where was I... This means I use about 72 MBTU of heat a year, at a cost of about $13.6 per BTU. So this CanSolair thing would save me $74/yr, getting me to the break-even point in 40 years, assuming the cost of wood does not rise (which it will).
Jesus Christ, the numbers were much better when they were discussing them on the news. Can anybody see a problem with my numbers? Maybe they were comparing a more expensive fuel source than local hardwood?