Don’t fall victim to the Snackwell effect: turn off lights and appliances when finished. (Photo: Flickr)

Consumers may be undermining their own energy-saving efforts by using efficient appliances more often, recent studies reveal. The phenomenon, called the Snackwell Effect, has been compared to dieters binging on low-calorie cookies, and it occurs when homeowners upgrade their homes or appliances but then use energy more frivolously. For example, a 2008 study found that people given energy-efficient washing machines washed more clothes. One couple, the Kings of W. Virginia, confess that they sometimes wash just one piece of clothing in their new high-efficiency clothes washer, something they would not have done before.

“It could be that by doing something virtuous, it gives you license to do something indulgent somewhere else,” says Loren Lutzenhiser of Portland State University.

The Effect continues to put a dent in many homeowners’ well-intentioned efforts. People who install efficient lights lose 5-12% of the expected energy savings by leaving them on longer, explains Karen Ehrhardt-Martinez of the American Council for an Energy Efficient Economy. People who buy an efficient furnace may lose 10-30% of their savings, probably from raising the thermostat.

One solution is to invest in devices that show consumers their electricity use by appliance or by household, so they know how much power they are consuming. Such devices include the Kill-a-Watt appliance monitor, or whole home monitors such as the PowerCost Monitor.

Whatever the solution, the take-away message is simple: when you upgrade, don’t slip into indulgent habits. Better yet, upgrade your habits as well and maximize your savings with a combination of efficiency upgrades and simple, satisfying conservation efforts.

• Read our top energy saving habits
• Invest in an energy-efficient appliance and flex your power to resist the Snackwell Effect
• Read background: “Consumers Can Sabotage Energy-Saving Efforts,” by Traci Watson (USA Today, 3/24/09)