Curbing Energy Use In Appliances That Are Off

KarmaOverDogma writes "The New York Times has an interesting piece on the slow but steady movement to reduce the power drain for appliances that are never truly turned off when they are powered down. In the typical house that's enough to light a 100-watt light bulb 24/7, according to Lawrence Berkeley National Laboratories, a research arm of the Energy Department. In the United States alone, over $1 billion per year is spent powering devices such as TV's VCR's, Computers and Chargers while they are 'off.' Called 'vampires' and 'wall-warts' by Energy Experts, there has been growing support of their recommendations to adopt industry-wide standards, which would require manufacturers to build appliances with significantly lower consumption when not in use."

Comments

Re:Meter

[max_entropy99]

Thinkgeek.com just happens to have such a device: http://www.thinkgeek.com/gadgets/electronic/7657/

Measuring wall-wart power usage.

[Latent Heat]

Appliances of any kind are typically rated in volt-amps, which tells you the current they draw knowing the voltage, but under worst-case conditions without telling you the power factor to know the P (watts) instead of the |S| (volt-amps). Applicance rating plates are meant to tell you how much current draw and hence how big a circuit breaker or fuse you need -- they are not energy ratings.

My own house runs about 45 watts. The furnace alone has a microprocessor in it that takes a good 16 watts. Each GFI (ground fault interrupter circuit breaker that prevents you from getting shocked in wet places like kitchen, bathroom, outdoors) takes up a watt, but you can eliminate that draw by leaving them "popped." I have three motion detector lights -- they save energy, but they take about 2-3 watts each when the lights are off. The garage door opener has a radio receiver that draws about 4. We have a remote control TV that takes 6 watts. Phone answering machines are good for about 4-5 watts. Oh, and a PCI motherboard (it is always "on" when the computer is plugged in) is good for about 4 watts -- I have mine on a "power center", but I can't get my wife to put her computer on a "power center."

I know this info by using either a power meter that the local utility loans out through the public library or by counting turns on the outside electric meter (If you meter says 7.2 on it, it means it is 7.2 watt-hours for every turn. If it takes 10 minutes to make one full turn with everything turned of, it makes 3600/(10X60) turns or 6 turns per hour, or the house is using 6X7.2 or 43.2 watts -- instead of standing outside counting a full turn of the meter, you can turn on a light inside of known wattage to bias the reading higher so the meter turns faster. Also, you have to time a complete turn because there is runnout in the power meter rotor -- it goes faster and slower over different parts of a turn, but it is calibrated to read to better than 1 percent for a complete turn.).

Re:$4 a person?

[rtaylor]

Ahem.. That is $4 per person per year for the TV and VCR only (two devices).

Microwave, washer, dryer, printer, phone, monitors, lamps, battery chargers (cell phone, laptop, etc.), cradles, etc. also take energy when in standby mode -- or what most people call off.

They list 1000kw per year per household, so at 7 cents per kw that works out to closer to $70 per year. If it adds between $0.50 and $1 to the manufacturing cost to reduce that by 50% it would probably be a net-win for most devices plugged in for most than 6 months.

Depends on where you live...

[bluGill]

If you live in southern California this is a good idea, paybacks in as little as 4 years. (Including government subsidies) If you live in MN like I do, you are looking at a 30 year payback if all goes well - which is longer than many roofs last. If you shovel the roof you might do better, but that is both dangerous (Don't fall off the roof), and harmful to the panels (which tend to be easily damaged when walked on).

If you live in areas with a lot of sun you are stupid not to investigate this. Many people live in climates where they do not pay off.

Re:Meter Kill A Watt P3 results

[saskboy]

I got a P3 for my Dad, and have since borrowed it to meter nearly everything in my house just for fun. [Yeah I said fun, this is Slashdot and if I consider plugging things in to test for Wattage use as fun, that's fine.] I got the meter from eBay, it was about $30.

Here are some of my results:
Air Conditioner wall unit: 2 hours: 17 minutes 3.12 kWh and 1300W when running.

Fridge from the 1970s, about 126W when running.

Microwave from 1980, 888W when running

Clock Radio from 1986, with the radio on and volume low, 0W measured.

Computer 1800+ AMD, 3 IDE HD, and Radeon AIW 8500DV /Speakers/Monitor/Modems/Sony VCR, 13" TV, UPS, all typically used, but the computer running 24/7:
185W approximately
214 hours 38.62kWh
1083 hours 188kWh