The folks at GreenPowerScience have provided a free collection of great DIY solar power tutorials.
You may need engineering chops to want to do this sort of thing, but the GreenPowerScience team seems to break things down in a way that makes an engineering or technology background optional. Here's the example that got me inspired to create my own residential solar power system:
I am not sold on the idea that solar power can be cost-effective. In the 2nd quarter of 2011, the average cost of residential solar power systems was $6.42 per Watt. I've heard of DIY solar power gurus claiming to achieve $1 per Watt...but I have also read that solar cells alone cost $2.50/Watt, and that the cost of other components adds up fast. When/if I build my own system inspired by the GreenPowerScience team, I hope to document my costs and time investment for a future post. My swag on financial break-even is as follows:
Divide the initial cost per Watt at installation by 1W x hours/day of sun x (1kW/1000W) x days of sunshine/year x 0.7 to account for reduced generation when sunshine is less direct x $/kWh. According to my math, the $6.42 per Watt system would take 46 years to pay for itself at 15 cents/kWh. Using the map of average daily solar radiation from nationalatlas.gov could help tighten these numbers a bit.
Here's an informative post from Michael Bluejay on the cost of electricity, and here is another where he makes the case that (subsidized) solar is affordable. Data from the US Energy Information Administration, show that the average cost per kilowatt hour in the USA is 11.5 cents, with a low of 7.99 cents in Idaho and a high of 28.10 cents in Hawaii.
It could be an educational, exciting, and productive form of charity/volunteer work to build and install residential photovoltaic power systems for families who are having difficulty making ends meet, instead of making one-time monetary donations. That sort of project could fit well with Christmas in April initiatives like this one, or Habitat for Humanity.