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Idle Efficiency
Vinay Gupta, 17 Jun 04

Efficient Power Supplies is a site dedicated to the topic of cleanly converting AC power to DC power in consumer and other electronics.

While the best power supplies are more than 90% efficient, some are only 20 to 40% efficient, wasting the majority of the electricity that passes through them. As a result, today's power supplies consume at least 2% of all U.S. electricity production. More efficient power supply designs could cut that usage in half, saving nearly $3 billion and about 24 million tons of carbon dioxide emissions per year.

What's interesting about this site is that it's focus also casts a shadow: the economic and cultural processes which result in the deployment of inefficient power supplies. A cheaper, less efficient power supply may save two dollars of manufacturing cost, ten dollars at retail - and cost the consumer fifty dollars over the lifetime of the product. The most deeply hidden cost - provision of grid infrastructure to carry the extra power used - is almost impossible to estimate, but Small Is Profitable by the Rocky Mountain Institute makes a good try.

Could it be our way of measuring the cost of products is fundamentally skewed? If, for example, one purchased products inclusive of a lifetime supply of electricity to go with them, there would be no problem encouraging people to deploy efficient devices: the real cost would be as clear as the sticker price.

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How long is the life time use? And does it factor in the time-value of money?

Posted by: Chris Durnell on 17 Jun 04

The inefficiency of most AC-DC power supplies is easy to experience. The so-called "wall warts" for devices like laptops, mobile phones, digital cameras -- pretty much any battery-powered device that can recharge by being plugged in -- are the most commonplace examples of AC-DC converters. You probably have one plugged in near you right now.

Go touch it.

Chances are, you pulled your fingers away pretty quickly. Most wall-wart power supplies are horribly inefficient, and the AC power that isn't converted into DC power is converted into something else: heat. The hotter the power supply, the less efficient it is.

Posted by: Jamais Cascio on 17 Jun 04

The reason for uber bad power units is you and me wanting a thingy that contains one for 5 bucks when we dang well know that means it only cost 20 cents to make and the maker only got 1 penny each profit.

How DO you think people make 19 buck cd players folks? They sure as hell dont use great parts thats how.

Now in general puters have better psus because heat is BAD and because a puter uses alot of energy and so a bad one would burn down the house and blow the breakers.

A 3 watt cd player on the other hand likely uses a 20 cent power block and is likely actauly using up 9 watts of power.

But you know what its hopeless because people only care about money and they dont care about quality.

Posted by: wintermane on 17 Jun 04

A minimal lifetime supply of 3 volt DC electricity costs about $30. It's a solar/dynamo flashlight/radio from Sun-Mate (

You can use the solar panel to charge the internal battery as well as AAs in the battery bay. if the sun isn't shining, there's a hand-crank you turn to generate power.

The radio is am, fm, TV, and shortwave.

Posted by: gmoke on 17 Jun 04

While you're absolutely right about power supplies, and it is a valuable point, the same thing is true of electric motors, and instead of them using 2% of all US power, they use around 40%. Seriously. There are motors everywhere, from your refrigerator to your air conditioning system, several motors in every computer (cooling fan, CD player, HD), etc. And the same cutting of corners happens with motor efficiency vs. initial cost.

If something is to be done to regulate component efficiency, it should be done to motors first.

Posted by: Jer on 17 Jun 04

Good point Jer. Amory Lovins (of RMI) actually has a somewhat-serious proposal that inefficient electrical equipment, including motors, be treated in a similar fashion to toxic waste. The idea is that inefficient electrical equipment should be identified, tracked and stigmatized, so that people can't dump low quality motors on the third world, any more than they can dump toxic waste.

In one casual discussion, he suggested that the trade in inefficient electrical equipment caused suffering in the same class as the global drug trade, because capital-starved governments wind up building power generation and distribution systems to fuel these wasteful motors. The capital which could have built hospitals and schools goes into extra grid capacity to run the inefficient equipment.

It was all off the cuff, but pretty damn impressive and plausible enough to me.

Posted by: Vinay on 17 Jun 04

re: "the economic and cultural processes which result in the deployment of inefficient power"

i think that's part of a larger critique of negative externalities or public bads, described thusly:

"Many public bads, like pollution, go with increased profits, so, all else being equal, the more money you get from profits, the more of those public bads you will be willing to tolerate. If profits are highly concentrated (as today they are; in the United States, 10 percent of all households hold 83 percent of all stocks), there will be a small group of people who want much more of those public bads than the rest of the population, and, being powerful and rich, they are likely to get their way." [also see :]

also i thought this dissection of US energy/environmental politics and policy along conservative/liberal lines was pretty interesting, particularly the psychological dimensions/type-traits from which the conflict/impasse arises:

"The Republican idea of energy development is mired in awe at the steady cadence of industrial achievement; in a philosophy of nature that celebrates man’s powers of development; and in a belief that economic growth depends on expanding opportunities for oil, natural gas, coal, and nuclear power by improving existing technology and limiting government interference. It is a philosophy founded on what is more than what might be in the future, on current demands and opportunities more than future dreams and future nightmares. The Republican energy strategy is about “active exploration” throughout the hemisphere; it is a policy of muscular development over idle or “romantic” plan-making. It takes a certain pleasure in man’s superiority over the world he inhabits; it assumes or aims to demonstrate that environmental worries are misguided or overstated; and it believes that gradual technological progress will ameliorate the ecological problems that actually exist."

"The liberal idea of energy blends a romantic desire for Elysian Fields, a conservation ethic, and a vision of American energy independence that requires a technological revolution in the way we make and use energy. Liberals pine for better and more efficient energy production while expressing dismay over many entrenched industrial techniques. They worry about what is being “lost forever” and dream about what might be achieved with a “new energy paradigm.” Most Democrats yearn for a world devoid of coal-fired power, nuclear power plants, and oil refineries, and imagine a new age of bio-refineries, wind farms, and solar power initiatives, with some Democrats willing to bear “clean coal.” A good energy policy, they say, is one of “energy self-sufficiency,” rooted in a belief that renewable energy sources, constantly replenishing themselves, will one day allow us to transcend our energy problems."

perhpas no so different afterall!

Posted by: reflexorset on 19 Jun 04

One way to get rid of household phantom loads is to plug appliances into a power strip; and then after you turn off the appliance, turn off the power strip. For instance, your TV which has a phantom load to keep the instant on feature working. Plug it into a power strip, turn it off, turn the power strip off. No more phantom load.

Posted by: gmoke on 19 Jun 04



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