Another thing I’d do is give some information away free as a teaser.
If you make a flyer or brochure, target it to a particular neighborhood. Find out what they pay for kilowatts per hour and figure up how much they could save by doing X.
For instance you could go out at 3 in the morning to all of the houses with porchlights on and hang a little card on the light that said, “If you had turned off this light instead of leaving it on all night, you could have saved $X.XX this year. For more tips, contact me!”
Of course walking up to people’s doors at 3am might not be the best idea, but you could just hang it on every porch light instead.
Or if you wanted to spend a little money you could buy an eco-friendly lightbulb or something and leave it on people’s porches and say how much that bulb will save them over a year, and say to contact you if they want to save more.
If you want to go door to door you could simply walk up to people’s houses and take a quick glance of the things they could improve just on the front of the house. Replacing the lightbulb on the front porch, fixing a leaky faucet, cutting the grass less often, whatever you see that could improve and give them a little breakdown of just what you see in the front yard. That may be enough to get them hooked and invite you in for more info.
Seems like a rough business to actually make money at, though I guess if you pick the right neighborhoods you may find clients. Many of the eco-friendly tips I’ve seen only save a couple of dollars a month, so assuming your consultation costs a couple hundred dollars, they aren’t going to see a return on their investment for a few years, most likely.