The cost of solar power is collapsing to the point that its use is about to explode across the United States, according to Kees Van Der Leun at Grist:
[T]he fact that 30 pounds of silicon, an amount that costs $700 to produce, is enough to generate a lifetime of household electricity baffled me. Over 25 years, the family would pay at least $25,000 for the same 100,000 kilowatt-hours (kWh) of electricity from fossil fuels — and its generation cost alone would total over $6,000!
Paul Krugman weighs in too, criticizing those who just can’t stop touting dirty coal and natural gas derived from tracking. Then he turns to the quickly falling cost savings of PV solar:
[P]rogress in solar panels has been so dramatic and sustained that, as a blog post at Scientific American put it, “there’s now frequent talk of a ‘Moore’s law’ in solar energy,” with prices adjusted for inflation falling around 7 percent a year.
Even more falling cost data at CNET.
The last I shopped, PV panels were approaching $5/peak watt. If you are very efficient and only use 1kw on average, and live in a place with about 10% average useable sunlight (like eastern Missouri), this means that you only need 1,000w / 10% x $5 = $50,000 to supply your electrical needs. This solar array will cover at least 600 square feet of south-facing full-sun-all-day surface.
If you use an air conditioner, and cannot store power up through the winter, you’ll probably need about five times that much. Or if you use electric heat or hot water, similar increase.
But if you get rid of refrigerators, freezers, and parasitic electronics (TV’s, stereos, alarm systems, etc) you can get by with less.
I am in favor of using wind and solar where reasonable. But check the numbers before getting rid of your $0.00008 per watt-hour grid power (cost read from my latest electric bill). That comes to $0.70 per watt-year, or 7 years before you pay for that solar watt (not including installation, repairs, and maintenance).
I recently got a bid from a solar provider: $30,000 would cover 70% of my home’s electrical bill. With tax credits and rebates, that would be decreased to $13,000. It would pay for itself in about 12 years.
I’ve been following PV for more years than I can remember and as much as i like/love the idea, it has been prohibitively expensive. Three years ago, I priced $7-9 per installed watt for our municipal facilities, and the payback on that was atrocious. I would not recommend solar PV unless you had tax incentives or other offsets. The cost has come down considerably and we just awarded a 30kW project for three buildings that works out to be $4.35 per installed watt (turnkey). It could have been cheaper if the low bidder hadn’t been non-responsive. The payback is much better, obviously.
Four months ago, I found PV panels for $1.79 per watt. They will bottom out eventually, but I don’t know at what level.
Wind is another matter and the ROI has not improved nearly as much as solar. I live in a rather windy area, but on the scale of 1 to 6, with six being the windiest sustained, Dallas-Fort Worth is only a 2. Unlike solar, wind is inconsistent and unpredictable. Unless I have a grant, I’m not paying for wind turbines on my facilities.
I also take a reduced demand and not off-the-grid approach to solar with my projects, meaning no batteries – the maintenance and life cycle costs make the payback far, far worse.
If you want to live off the grid, there are ways. But you really have to take the Greek austerity measures to heart.