Going green with air conditioning is complicated

But there's a lot of new technology that you should know about to find the best fit for your lifestyle, and your home.

First off, those clunky, chunky systems of the past are gone.

Depending on how much money you want to spend, there are new systems that can cut your electricity consumption in half, that make very little noise, and even allow you to set different humidity and temperatures levels throughout the house.

Price vs. environment

Your new air conditioner will be more efficient. The big question is whether buying the most efficient system, because you are worried about your carbon footprint, is worth it financially.

"If you can't earn your money back in five years, it's not cost effective," said Karen Schneider, a spokeswoman for Energy Star, an energy efficiency program run by the Environmental Protection Agency and Department of Energy.

The government has established an energy efficient ratings system for central air conditioners. The minimum since 2006 is 13. Systems 15 years old or older probably have a rating of 10 or lower.

A family in central Ohio might spend $250 to $350 on electricity for the four months or so that air conditioning is desired. A new air conditioner with a 13 rating could save about $75 a summer and drive down electricity consumption by about 25 percent. A family in Texas or some other warm-weather state, obviously, would save a lot more.

Most of the bids my wife and I received to replace our cranky 3-ton, 15-year-old air conditioner with a 13-rated system, plus some minor duct work, ranged from about $2,300 to $3,000.