The problem: Most bills don't break down energy consumption by category, such as heating, cooking, and lighting, making it almost impossible to target where you are overspending.
How to spot it: Sign up for one of the dozens of new pilot programs offered by regional utility companies to help homeowners pinpoint and control their usage with a digital energy-management system.
How to stop it: Hook major appliances and electronics up to smart plugs, or relays, which transfer information to a Wi-Fi–enabled control panel that sits at a central location in your home, such as the kitchen counter. This device—it can also switch appliances on or off and adjust a programmable thermostat from home or remotely via a computer or smartphone—gives you a real-time look at how much energy you're using in kilowatt hours and dollars. "You can determine immediately what's costing you the most money and decide if it's worth keeping that item plugged in," says Paige Layne of Duke Energy, which is currently supplying customers with Cisco's Home Energy Controller (shown at left) free of charge in select markets in the South and Midwest. If your utility isn't offering such trials, you can buy a monitoring kit at an electronics store, such as Best Buy, for as little as $100.
The payoff: Save 10 to 25 percent on your electric bill by tracking
down unwanted energy hogs and using the consumption data to change your habits.