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Did you know that three-quarters of the energy your appliances burn is used while they’re turned off? It’s true. Our ever wise and helpful green advice columnist, Umbra Fisk, looked it up. She tells us that Americans waste an estimated $1 billion a year powering “vampire appliances” we’re not even using.

In this classic from the video archives, Umbra has a few thoughts on how to put a stake through the heart of these silent budget killers — or at least put them to sleep at night. The first key: Just because the switch says “OFF,” don’t assume that the little monster isn’t sucking your wallet dry.

This year marks the 10th anniversary of our Ask Umbra advice column, and to celebrate, we’re pulling a favorite gem of eco-advice out of the archives each week.

Send your green-living questions to Umbra.

For even more green goodness, you can follow Umbra on Twitter (@AskUmbra) or become a fan on Facebook.