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Computers Causing 2nd Hump In Peak Power Demand
Hugh Pickens writes "Traditional peak power hours — the time during the day when power demand shoots up — run from 4 p.m. to 7 p.m. when air conditioning begins to ramp up and people start heading for malls and home but utilities are now seeing another peak power problem evolve with a second surge that runs from about 8 p.m. to 9 p.m. when people head toward their big screen TVs and home computers. 'It is [not] so much a peak as it is a plateau,' says Andrew Tang, senior director of the smart energy web at Pacific Gas & Electric. '8 p.m. is kind of a recent phenomenon.' Providing power during the peak hours is already a costly proposition because approximately 10 percent of the existing generating capacity only gets used about 50 hours a year: Most of the time, that expensive capital equipment sits idle waiting for a crisis. Efforts to reduce demand are already underway with TV manufacturers working to reduce the power consumption in LCD and plasma while Intel and PC manufacturers are cranking down computer power consumption. 'Without a doubt, there's demand' for green PCs, says Rick Chernick, CEO of HP partner Connecting Point, adding that the need to be green is especially noticeable among medical industry enterprise customers."
CRTs are power hogs, but your laser printer is the biggest power hog of your computer system. The fuser gets up to 2k F to melt the toner on the paper.
Plasma displays use less than CRT, LED uses less than plasma.
A space heater uses more juice than just about anything in your house save your AC or (if it's electric) your water heater. Your toaster comes in a good second (while it's actually toasting, which isn't long) followed by your microwave.
If a device's primary purpose is to heat something, it uses a shitload of electricity.
All your electric appliances/gizmos are rated in watts. Just RTFM, it's usually listed on the back page. If you have no FM it usually says on the back of the appliance how many watts it consumes.
Free Martian Whores!
You won't find a more efficient design on the market right now. Samsung's 67" LED DLP set draws about 120 watts.
A quick google finds these:
65" Panasonic Plasma at 800W.
65" Olevia LCD (probably CFL backlit) at 540W.
55" Samsung LED-backlit LCD at 250W (note that this set is smaller than the rest)
Car battery capacity is usually between 40-60 amp-h. That is, if you wanted to use battery power for three hours of peak, you would get (generous estimation) of 20 amp-h per battery. Your battery gives 12 volts, and, again under ideal conditions you should get 12*20 = 240 W-h per battery for the peak time.
A standard light bulb is 100 watts. Your plasma TV may be 800-1200 watts.
Thus to run the TV for three hours you would need five batteries, and that assumes that you could run them to dry. Lead acid batteries can produce surge power pretty well, but it would likely be cost prohibitive unless you could get a lot of duty cycles out of them.
Looking at Sears -- a cheap car battery is around $50. Electricity costs $0.08 per kwh where I am. Thus to equal the cost of one battery you would need to produce 50/.08 = 625 KW-h of electricity before being spent. That is 625,000 W-h or 1,000 charge cycles.
I'm not sure if a battery can handle this before getting corroded and functioning badly. Of course, this is only the cost of the battery, and really what you care about is the delta cost from night and day electricity. Additionally, people could not use retail car batteries but could get cheaper lead-acid apparatuses.
At delta cost of $.05 per kw-h, then if you could get more than 1000 charge cycles from the battery, then anything above this is profit on the order of $.05 KWh * 1kW * 3h = $.15 = 15 cents per day for your plasma. Is it worth it?
The short answer is no. The long answer is probably not.
Slashdotter, ID #101. UIDs are in binary, right?
FYI, you don't need to notify the power company if your main disconnect only switches between utility and generator power (can't backfeed power because generator power can't get to the utility with the power transfer switch). On the other hand, you do need to notify the utility if you have a grid-tied inverter that feeds power back into the grid from solar/wind/etc. Note though that the utility needs to do nothing to disconnect you when they're working on the lines. NEC code requires grid-tie inverters to completely disconnect the utility feed when it detects utility power has been shutdown, so they can't feed power back when line workers are working on the lines (like after a large storm). Also, you are required to have master disconnection on the exterior of your home that the utility or line workers can lock, but that shouldn't affect power to your house if you're generating, only your ability to sell power back to the utility during the disconnect time.
Disclaimer: My experience on this is from permitting/installing solar and wind grid-tie systems, as well as from a good friend who is an electrical line worker.