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Power Demand From US Homes Expected To Fall For a Decade

We hear all the time that household energy consumption is rising, both in the U.S. and around the world. That's been true in the big picture for several decades at least, but reader captainkoloth, with his first accepted submission, points to an Associated Press article with some encouraging news on this front: the rate of growth in U.S. household energy use, and household energy use itself, is expected to decline slightly over the next 10 years. Take it for what you will, but that conclusion is drawn by the Electric Power Research Institute, "a nonprofit group funded by the utility industry."

14 of 261 comments (clear)

  1. Not a huge surprise by NoNonAlphaCharsHere · · Score: 4, Insightful

    As the last of the vacuum tubes (incandescent light bulbs and CRTs) get phased out, power consumption goes down. Now if we could just find a way to get rid of (most) fractional horsepower motors.

    1. Re:Not a huge surprise by bunratty · · Score: 5, Interesting

      California's per capita electricity use has been nearly level for decades due to their energy efficiency standards. Now that similar standards are being adopted nationwide, nationwide electricity use is leveling off. If we try even harder, we can reduce electricity use. Not only does it not harm the economy, it helps us all save money because we're paying for less energy, and we're paying less per unit of energy because demand is lower.

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      What a fool believes, he sees, no wise man has the power to reason away.
    2. Re:Not a huge surprise by Chris+Burke · · Score: 5, Informative

      What a lot of people don't realize about CFL's is that they can have really fucking poor power factors, we are talking in the region of 0.3 for the really cheap ones, so you may only be getting billed for 20W but the power company is feeling the burn of 60.

      If by 'burn' you mean transmission losses then yes. If you mean 'burn' as in they have to actually produce 60W to run a 20W CFL then no, power factor does not work that way.

      Power factor comes from the fact that CFLs are not a purely resistive load. But energy stored in a capacitor or inductor is not lost. It is returned to the grid. Your utility does need extra equipment to manage apparent vs real power and make their distribution more efficient (mostly eliminating the one downside of low power factor, but that's as far as it goes (and they already have this equipment).

      Power factor as a negative of CFLs is a complete red herring, and whoever told you it was a big deal was taking advantage of you in order to slander a fine energy-saving technology. In reality all you can say is that there advantage over incandescents is slightly less great.

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      The enemies of Democracy are
    3. Re:Not a huge surprise by PPH · · Score: 4, Informative

      Now if we could just find a way to get rid of (most) fractional horsepower motors.

      Make that fixed speed, single phase fractional horsepower motors. Three phase motors are more efficient. And even more system efficiencies can be squeezed out by varying motor speed to match the mechanical load.

      As power semiconductor prices come down, small variable frequency drives (VFD) will become common. These take single phase input and produce variable frequency, multiple phase outputs for a motor and provide power factor correction and other efficiency improving functions as well.

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    4. Re:Not a huge surprise by Technician · · Score: 5, Interesting

      Fractional HP motors are not the problem. Bad motors are a problem. Case in point, the circulation pump on a solar installation used a 1/10th HP pump. The pump drew about 300 watts or about the energy of 1/2 hp. The pump was replaced with a DC brushless motor. A single 60 watt PE panel was placed on the roof. Now when the sun shines on the collector the pump runs. This eliminated the differential thermostat controller and 3/4 of the power use to circulate the water. It removed 100% of the need for utility power to run the pump.

      The move was made for two reasons. One was power efficiency. The other was for reliability. The old system would boil over in a power outage. The new one is unaffected by power outages.

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    5. Re:Not a huge surprise by hawguy · · Score: 5, Informative

      What a lot of people don't realize about CFL's is that they can have really fucking poor power factors, we are talking in the region of 0.3 for the really cheap ones, so you may only be getting billed for 20W but the power company is feeling the burn of 60. Add to that the fact that they are essentially an attempt to cram a LPMV lamp into a really awkward form factor (because for some reason having a strip light in the living room is unthinkable, but having it as a point source and then wrapping a shade round it to diffuse the light is fine) subjectively poor spectrum, mercury content (I know it's not a lot, but if I cant have lead in my solder you can't have mercury in your bulbs) and poor performance in cold weather they are a really a bad solution to an already solved problem.

      While it's true that CFL's can have bad power factors, it's not quite as bad for the power companies as it sounds.

      First, regardless of the PF, a 20W CFL uses 20W of energy, the power company doesn't have to burn 60W of coal to feed your .3 PF 20W bulb - they only burn 20W of coal.

      It is true that they have higher current draw from a CFL due to the 60VA apparent load, but that doesn't really matter since for most homes, lighting energy is dwarfed by other uses, so the power infrastructure to your home is sized to handle your 3000W oven heating element and 7000W tankless water heater. Granted, the low PF can lead to higher resistive losses in wiring, but not nearly enough to erase the gain in efficiency by moving from incandescent to CFL's.

      Large commercial installations with hundreds or thousands of lamps do take the power factor into account and size the electrical infrastructure accordingly. Those that are billed by power factor can use power factor correction to correct the power factor (or use high PF lamps), and still save money due to the efficiency of CFL's. Labor costs alone in reduced bulb replacement make CFL's a good deal for business with a lot of lights.

      Poor power factors are nothing new - many newer computer power supplies have built-in PFC to give them a decent PF, but older power supplies could dip to around .6.

    6. Re:Not a huge surprise by Chris+Burke · · Score: 5, Informative

      Returned to the grid arbitrarily out of phase, which requires utility companies to employ large PFC installations and / or take the hit with extra generating capacity.

      Only to compensate for the extra line loss! Which is important, but small compared to the real power consumed. You can measure watts produced at a generator, volt-amps in the load, and power in the load and see that the power produced by the generator is only slightly more than the real power consumed by the load. Implying that it is more, that CFLs don't save power and use the full volt-amps worth of power even with 0 PFC is pure ignorant bullshit FUD.

      But they do have PFC installed.

      Suggesting that widespread adoption of low power factor equipment is a non-issue is just another attempt at green-washing with bullshit.

      We're just talking about low-power usage lighting when the PF for the home will be dominated by HVAC and large appliances. Acting like the claim that PF is a red herring for CFLs is the same as saying it's a non-issue if your whole house was running a low PF is just a bullshit way to cover for you getting called out on your flagrant ignorance.

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      The enemies of Democracy are
    7. Re:Not a huge surprise by Darkness404 · · Score: 5, Insightful

      Um... utility companies have a legal monopoly. They have already gamed the system and are outside of the free market.

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      Taxation is legalized theft, no more, no less.
    8. Re:Not a huge surprise by iamhassi · · Score: 4, Interesting

      Not only does it not harm the economy, it helps us all save money because we're paying for less energy, and we're paying less per unit of energy because demand is lower.

      Maybe in California, but some parts of the country have seen almost yearly rate increases, so cutting your energy usage by 30% doesn't help much when they raise rates 30%.

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      my karma will be here long after I'm gone
  2. Probably true by drinkypoo · · Score: 5, Insightful

    If you can't afford to pay the light bill, your electricity consumption is going to decrease sharply.

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    "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  3. Efficiency is only part of the equation by antifoidulus · · Score: 4, Insightful

    demographic changes and societal changes are probably at least as responsible, if not more responsible, for the changes. Due to the "great recession" American kids are finally figuring out what their counterparts in other rich countries(Italy and Japan foremost among them) that living with mom and dad after graduation and even employment isn't as bad as either forking out massive amounts of money in rent to someone else every month or buying a house/apartment that is pretty much guaranteed to be worth less than you paid for it the second you sign the lease.

    As such, as more people live in the same household per capita energy consumption tends to fall as there are more "economies of scale" in things like refrigeration and heating/cooling.....

    Whether or not this will be a long term trend like it is in Italy and Japan still remains a question and is critical to long term residential energy consumption estimates.

  4. Re:Headline is wrong then by AdamHaun · · Score: 4, Informative

    Both are right. The rate of demand increase is falling and is expected to go negative in a few years. From the article:

    Over the next decade, experts expect residential power use to fall, reversing an upward trend that has been almost uninterrupted since Thomas Edison invented the modern light bulb. ...

    From 1980 to 2000, residential power demand grew by about 2.5 percent a year. From 2000 to 2010, the growth rate slowed to 2 percent. Over the next 10 years, demand is expected to decline by about 0.5 percent a year, according to the Electric Power Research Institute, a nonprofit group funded by the utility industry.

    Overall demand, including from factories and businesses, is still expected to grow, but at only a 0.7 percent annual rate through 2035, the government says. That's well below the average of 2.5 percent a year the past four decades.

    The article is actually pretty detailed and quantitative (at least for the AP). It lists the big drivers as being more efficient lighting and appliances, federal and state efficiency subsidies, and people trying to save money. Over the next couple decades they're projecting ~20-25% reduction in appliance energy use and ~50% reduction in lighting energy use.

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  5. Re:Obviously by roman_mir · · Score: 5, Interesting

    Of-course, this is consistent with the depression that US and many other Western nations are in.

    Depression is huge loss of production capacity - too few people have meaningful goods producing jobs in the market. The way USA is dealing with the loss of production is by abusing the status of its reserve currency, so it's printing dollars to buy consumer goods and the producers also vendor financing this spending.

    So there are fewer and fewer jobs, the production capacity is going down (53Billion USD/month trade deficit), the debt is growing because government spending is constantly increasing in absolute numbers. The so called main stream 'economists' are saying that commodity prices do not matter because consumers are not buying commodities, this is completely dismissing the fact that somebody must buy the commodities to build all those consumer goods. Gold is going up only relative to the destroyed currency. Silver is almost a monetary metal itself, and Apple is selling not only in USA (which has no real purchasing power left since it has almost no production capacity left), but it's selling world wide. Of-course at some point the government will come after all of these American companies that are still making money abroad, saying that they must pay more for 'fairness' sake and will force them to liquidate various assets and to pay gigantic taxes on what will be called their "windfall" profits.

    Money destruction is the same reason HFT is up, and bogus government "Job Acts" will only worsen the situation, while the crowd will be calling for various misplaced solutions that come out of general misunderstanding of what is happening.

  6. How to Lie with Statististics by WebManWalking · · Score: 4, Insightful

    You were absolutely right to be concerned about the rate of growth metric. Consider 1 + 2 + 3 + 4 + ...

    The 2 represents a doubling of the sum so far (200%). Now the sum is 3, so the 3 represents a 100% increase. Now the sum is 6, so the 4 represents a 67% increase. Now the sum is 10, so the 5 represents a 50% increase. Now the sum is 15, so the 6 represents a 40% increase. And so on.

    Now suppose that these numbers represent electricity usage. Although usage is monotonically increasing, the rate of growth is monotonically decreasing. Other commenters have pointed out that "TFA" says actual usage will go down. But you were right to be concerned. If actual usage is expected to go down, why didn't they say that? Why did they say that the rate of growth is expected to go down?? That phrase is a major red flag to identify someone who's trying to lie with statistics.