If you've been wanting to reduce your home energy use, to save money and reduce dependence on fossil fuels, you've no doubt wondered how much electricity various appliances use. Without that knowledge, it's hard to know how to most strategically cut back. Incredibly, a $500,000 home gives its owner less feedback about its workings than a $500 car.
When I first explored this issue, I bought a Kill a Watt meter that can measure the energy use of most anything that plugs into the wall. But it couldn't measure the real energy hogs, like central air conditioners, electric dryers, recessed lighting or dishwashers. So I bought a $150 T.E.D. meter that provides a real time measurement of your home energy use. With that device, I learned that my A/C unit uses 3500 watts of electricity when on, and the electric dryer uses nearly 4000. But energy meters like the T.E.D. are potentially dangerous to install, because there sensor has to be attached to the fuse box.
So, I wondered, would it be possible to design a device that could be placed on the electric meter outside, where it could measure how fast the dial turns and transmit the measurement to a handheld device inside the house? Lo and behold, such a device has finally been made available by Black and Decker! It's safe and legal for any homeowner to install, and costs less than the other whole-house energy monitors (about $100). After an hour spent installing it, you'll be able to walk around the house with the handheld monitor, turn various appliances and lights on and off, and see how much energy each one uses. With this knowledge, it's much easier to make decisions about how to cut back on consumption.
UPDATE, Jan. 13, 2010: The Black and Decker model has some drawbacks, primary among them is that the meter only tracks energy use in 100 watt increments. A CFL lightbulb may use only 14 watts, so if you turn several of them off, the meter won't show any reduction in energy use. My house generally uses so little energy that I couldn't even get the B&D model to register anything. It may work best for houses that use lots of appliances. For now, I'm using my T.E.D. meter, which, though trickier to install, tracks energy use in 10 watt increments and is much more accurate.
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