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Computers Causing 2nd Hump In Peak Power Demand 375

Posted by CmdrTaco
from the that's-why-i-compute-with-the-monitor-off dept.
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."
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Computers Causing 2nd Hump In Peak Power Demand

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  • Re:Stupid Question (Score:4, Informative)

    by LWATCDR (28044) on Monday October 20, 2008 @12:38PM (#25442499) Homepage Journal

    I think that the problem is that very few people have 13 to 17 inch LCD TVs anymore.
    They are more power efficient but bigger. THe back light is the real killer.

  • by Anonymous Coward on Monday October 20, 2008 @12:41PM (#25442537)

    As prices fall, folks are bigger and more electronics, thereby nullifying any power savings. And when you consider that everything these days being developed needs to be plugged in, it's only going to get worse. I don't buy much, if any electronics, but the folks who need the latest blinky power hungry electronic gadget outnumber people like me.

  • Re:Stupid Question (Score:5, Informative)

    by mcgrew (92797) * on Monday October 20, 2008 @12:44PM (#25442607) Homepage Journal

    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.

  • Re:what about.. (Score:3, Informative)

    by sexconker (1179573) on Monday October 20, 2008 @12:55PM (#25442777)

    The other 90% is your standard generation.
    he 10% is a buffer for high-demand hours, for leeway in routing, minimizing outages during maintenance, and emergencies.

    It's (mostly) separate hardware that kicks in only when needed.

    They're saying that the power usage throughout the day has developed a second high point that often requires the extra hardware to kick in. They mention this period being a plateau, meaning it lasts a long time. Running extra hardware is expensive, running it for a long time is more expensive.

    Most of the time when those things are idle does NOT apply to the 50 hours when it's at 10%. (I believe you meant to ask if the time when it's at only 10% (and thus idle 90%) applies to the 50 hours when it's idle).

    They're either on of off, in large groups. They're expensive to start and stop. So the answer to your question is mu. T he extra hardware doesn't run at 10% like a CPU. The extra hardware runs at 100% and adds to the capacity of the grid.

    Taking the whole grid into account, you could classify banks of extra hardware, and at any given time find the % of which are on and off, but the only thing that matters is when they're on in your area. You par for generation and delivery separately, remember.

  • Re:I Thought (Score:3, Informative)

    by Chirs (87576) on Monday October 20, 2008 @12:57PM (#25442807)

    LCDs _do_ save power compared to equivalently-sized CRTs. Quite significantly, in fact. My 24" LCD monitor uses half as much power as my older 21" CRT.

    However, I suspect that when they moved to LCDs many people also upgraded to physically larger TVs.

    The other thing to consider is that many people have plasma displays, which consume significantly more power than LCDs.

  • Re:Stupid Question (Score:4, Informative)

    by pjt33 (739471) on Monday October 20, 2008 @12:59PM (#25442829)

    If a device's primary purpose is to heat something, it uses a shitload of electricity.

    The big power spikes in the UK are at the start of the ad breaks in soaps, when millions of people get up to turn on the kettle and make a cup of tea.

  • LED-source DLP FTW (Score:5, Informative)

    by raygundan (16760) on Monday October 20, 2008 @01:09PM (#25442999) Homepage

    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)

  • Re:what about.. (Score:3, Informative)

    by AlecC (512609) <aleccawley@gmail.com> on Monday October 20, 2008 @01:17PM (#25443115)

    The 90%, or a large slice of it, is nuclear and large coal fired power stations that are hard to turn on and off. These are the baseload stations, and they run 24/7. Then there are lighter-weight stations that can be turned on and off in an hour or two, which run during the day. Then you have some very lightweight stations using technologies such as gas turbines, which can spin up in seconds. These are turned on just at the peaks, and constitute the t10% which is rarely used.

  • Re:what about.. (Score:3, Informative)

    by Orne (144925) on Monday October 20, 2008 @01:21PM (#25443183) Homepage

    Well, most of the time, the plants sit locked up and offline. About a week before the projected peak, the regional entities will issue hot weather alerts indicating if it is projected that those "peakers" would be needed. On the bulk power level, electricity cannot be stored, it can only be produced in near-equal amounts to the energy being consumed by residential, commercial, and industrial demand sources. It does noone any good to have a powerplant on standby if its energy is not needed.

    In normal operations, you have a class of cheap-fuel plants (aka base load) running on Coal and Nuclear that pretty much run flat-out full output all 365 days of the year. Somewhere in there you also have your Wind, Solar and Hydro plants, no fuel cost but less predictability & control of their output. Next, you have your marginal Combined Cycle plants running on Oil and Natural Gas, which have the capability to control and maintain their output between minimum and maximum.

    At the top of the heap are those Combustion Turbine (jet engines strapped to the ground) and Diesel, very expensive but very very quick response -- these are the resources that run 50 hours a year. But that's ok, because 360/365 days of the year you don't need that amount of generation to be produced.

  • by neapolitan (1100101) on Monday October 20, 2008 @01:25PM (#25443261)

    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.

  • Re:Wow. (Score:5, Informative)

    by TooMuchToDo (882796) on Monday October 20, 2008 @01:31PM (#25443365)

    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.

  • Re:Stupid Question (Score:4, Informative)

    by TooMuchToDo (882796) on Monday October 20, 2008 @01:33PM (#25443387)

    As TV manufacturers move from Cold Cathode Fluorescent backlights to OLED backlights, you'll see a significant drop in power use. What really needs to be dropped is standby power, which is being sucked up the whole time the TV is off.

  • Re:Simple solution. (Score:3, Informative)

    by TooMuchToDo (882796) on Monday October 20, 2008 @01:42PM (#25443531)

    $0.07/KwH from ComEd (Nuclear) in Northern Illinois suburb.

  • by 0100010001010011 (652467) on Monday October 20, 2008 @01:48PM (#25443609)

    If you were to do this you wouldn't use a Car Battery. You'd use a deep cycle. Second you wouldn't get a deep cycle the size of a car battery. Get a Fork Lift battery. 1300+ Ah.

  • Re:Simple solution. (Score:3, Informative)

    by Fjandr (66656) on Monday October 20, 2008 @02:01PM (#25443775) Homepage Journal

    It's called time-of-use metering, and is offered a lot of places in the US. Contact your power company to see if it's available where you live.

  • Re:Wow. (Score:4, Informative)

    by Idiomatick (976696) on Monday October 20, 2008 @02:08PM (#25443901)

    A command economy declared to be a terrorist state which has been gimped repeatedly many/most countries not being allowed to trade with them at all.... Hey Somalia is a free trade market too right. Wonder why its not rolling in the money (Oh and its not as badly economically gimped as north korea by a longshot). Really really funny.

  • Re:Simple solution. (Score:3, Informative)

    by TooMuchToDo (882796) on Monday October 20, 2008 @02:28PM (#25444219)

    So I shouldn't tell you that with time of day metering, the price goes down to $0.01/KwH between midnight and 4am? =)

  • Re:Wow. (Score:2, Informative)

    by m0rph3us0 (549631) on Monday October 20, 2008 @02:38PM (#25444359)

    Given the amount of looting I would hardly say the situation in Somalia is a free market. Free markets should ideally be free from coercion by force. "Somalia" is a collection of small dictatorships that steal everything worth stealing.

  • by Teufelhunde (1159113) on Monday October 20, 2008 @03:02PM (#25444649)

    Without a doubt, there's demand,' for green PC's

    Not true, I sell computers and at my store we have a 'green' tower that uses 70% less power then the other towers. For the entire month that we have had these towers, I have sold 0 of them, and it isn't because I haven't been trying.

  • by Anonymous Coward on Monday October 20, 2008 @03:17PM (#25444833)

    Points of interest -

    1. The Shockley-Queisser Limit doesn't give a rat's ass whether you use twice as much electricity. There are limits to solar conversions.

    2. The point of the article is to solve a problem. Not to make less of a problem. To solve a problem. I repeated it for comprehension. The problem is that the cheapest forms of generation -- coal and (with caveats) nuclear -- are cheap because the plants work well at producing base-load power. They run at a constant rate. So they are ill-equipped to handle peaks in demand. That is done with less efficient gas plants that can handle being turned off and on quickly.

    So the problem solve is levelizing the peaks in demand. This is a problem of deviations from the mean, and is INDEPENDENT of the total amount consumed.

    *poof* there goes your argument. Since you didn't bother to understand the problem, I'm not sure why I should take your pro-consumption rant seriously.

  • Re:Simple solution. (Score:3, Informative)

    by BlackSnake112 (912158) on Monday October 20, 2008 @03:25PM (#25444925)

    Better off with a attic fan(s) or whole house fan. By lowering the heat load in the attic, your house will feel cooler. If the temp drops a little bit in the evening, a whole house fan is great. It sucks the air out of the house into the attic (the out) and cooler air is drawn in.

    Those are a lot cheaper the a heat pump. Heat pump vs normal AC (or normal heater) heat pump is a lot more expansive to run VS ac. No contest here in Virginia. Even though the winters are no whee near as cold as places north, a regular gas/oil forced hot air furnace costs less to run then the heat pumps do. I know this cause there is a new housing development. Same construction in the homes (2X6 in exterior walls with more insulation), different heating/cooling systems. The heat pump based houses have the highest heating and cooling bills. The best (lowest bills) are the homes that use the water/slurry geothermal heating based system. Almost free AC. The temp is average 68 degrees from the ground year round here. And heating from 68 degrees is a lot cheaper then from 30 (or lower) degrees.

  • by Cytotoxic (245301) on Monday October 20, 2008 @05:42PM (#25446621)

    Um.. car batteries are deep cycle batteries.

    Actually, they are not. Car batteries are starter batteries - used to provide a short burst of high current (cranking amps in the car application). Deep cycle batteries are used to provide long steady power at constant voltage - like in marine applications, forklifts, golf carts, etc. This is the type of battery you would use for off-peak power storage, or for your solar / wind power array. You don't want to deep cycle your car battery, it will likely shorten it's life.

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