Several years ago I reported that my average electricity usage in the non-summer months was a meager 4 KW-hr per day—not bad at all for a 2,500-square foot home. In the last couple years, my energy use has been higher: as much as 5-6 KW-hr/day.
What happened? Well, I acquired some kittens. While they rarely flip any light switches or turn on any energy-sucking electronic equipment, they do have a water fountain that runs 24 hours a day, although I don’t imagine that uses more than, oh, 20 watts. A bigger heavy-hitter was a dual-CPU high-powered HP workstation, replete with four fans and a relatively speedy graphics chip. I wondered how much energy this actually used so I purchased a Kill-A-Watt power-measuring device (~$20). The verdict: the computer uses up to 222 watts!
Below is a table of the measured energy consumption of other items in my home. After the computer, the TV and the stereo system are the next biggest energy hogs, although at roughly 80 watts each, they use less than a Thomas Edison-style 100-watt incandescent light bulb. (My compact refrigerator, shredder and printer actually use more while operating, but they are only on sparingly or intermittently.)
|Item||In Use (W)||Stand-by (W)||Hibernate or Plugged-in (W)|
|Yamaha P-70 electronic piano||7.5||7.0||2.8|
|Princeton VL1716 monitor||28.2||0|
|Samsung ML-2580 laser printer||100-500 (printing)||6.5||0.0|
|HP xw-6500 workstation||178-222||6.0||4.7 ;4.2 (plugged in)|
|Dell Mini 9 netbook||10 (fully charged); 20-29 (charging)||0 (fully charged); 20 (charging)||0 (fully charged); 20 (charging)|
|Thinkpad T60p laptop with iGo charger||37-44||1.0||0|
|Viewsonic VP930b monitor||38||0||0|
|Kyocera cell-phone charger||0 (charging complete)||0 (phone unplugged)|
|Light with 23W fluorescent light bulb||25||–||0|
|GE GMR04HASACS compact refrigerator*||96-118||0||0|
|Onkyo TX-DS484 receiver||59 without subwoofer; 68-79 with subwoofer||1.7||0|
|Philips DVDR3505||2.2||2.2 (can’t turn off entirely)|
|Philips 30PW850H TV||82||0||0|
*EnergyGuide estimated usage = 345 kWh/year = .95 kWh/day
Unfortunately, I never did get around to measuring the power consumption of the kitty water fountain, and I have since resold the Kill-A-Watt device. But it looks like I can’t really blame my two furry housemates too much for the increased energy usage, too bad.