There are commercial home wind towers you can buy, rather than build yourself, for local wind generation. It requires an average annual wind speed of 4-6 mph or higher to be effective. (I don't have that requirement in place, here.)

You can lay out enough solar panels, using today's efficiencies, on an 1800 square foot house, to completely supply all lighting, appliances and heating requirements for a small family, at least in the Southwest region. All it would need (going through a commercial contractor) is about 2% of the market value of the house!!!

The least costly benefit available imemdiately as MarkS says above is sensible conservation and passive means.

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