There was an article in the New York Times this week about one man’s “energy diet.” The writer, Andrew Postman, managed to reduce his carbon emissions by almost one ton, without selling his house and moving into a cave. Heck, he didn’t even give up his flat-screen high-def 37-inch TV.

He replaced his regular light bulbs with compact fluorescents, lowered his thermostat in the winter, shortened his shower, and lowered the water temperature on his washing machine. He canceled a bunch of catalog subscriptions, and turned off his cable and satellite box when he went on vacation. He wrapped his hot water heater in a thermal blanket.

My family engaged in a similar pursuit this past month. We and several of our neighbors organized an “Energy Star” challenge. While our goals were noble, our form of feedback was as selfish as we could get: dollars off our monthly electricity bill.

Here were the rules: every participating household paid $10 to enter. We watched a documentary, Kilowatt Ours, together, and both got inspired and informed about how to reduce our electricity usage. The winner was the household whose September electricity bill was the smallest, compared to their August bill. (Greatest percentage decrease in average daily kilowatt hours, to be precise.)

The winner (we’ll compare our bills this Saturday night around a full-moon campfire) will receive half of the total entrance fee. The other half will go towards improving the energy efficiency of our Common House.

For the first time in my 41 years, I learned how to read an electricity bill (it isn’t hard). We installed compact fluorescents everywhere (total cost of bulbs, at Costco, was under $20. We put the TV, VCR, DVD, Boombox, and computer on power strips and switched them off when not in use. We unplugged phone and battery chargers when they weren’t actively charging, and we were careful to switch off lights we weren’t using. I took shorter showers.

The result: our energy usage dropped from 31 kWh/day to 16. Our August bill was $81. Our September bill was $41. By spending $20 and making tiny changes to our lives, we are on track to save almost 500 bucks a year, as well as make a big difference in the world.

How big? Our electrical utility, Duke Energy, is considering building two new coal-fired electricity plants in North Carolina to meet the expected demand surge. If conservation became a trend down here, those two plants, along with their smells, pollution and strip-mining, would not be needed.

For information on how to save big on your electric bill, visit KilowattOurs.org.