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Saving Power in your Home Office

cweditor writes "Rob Mitchell shows how he measured energy use of all his home office equipment, and then targeted the energy pigs for replacement. With better equipment choices, he'd save $90/year. If you've got more than a couple of computers and printers at home (and if you're a Slashdot reader, you probably do), the savings would be a lot higher. Includes detailed formulas as well as a spreadsheet on monitor energy usage."

11 of 285 comments (clear)

  1. Saving elsewhere by luvirini · · Score: 5, Insightful

    A typical slashdotter will likely save way more both nature and money in a year by just not buying one of the gadgets..

    Ofcourse saving electricity is good, but often the total enviromental cost of disposing of the previous thing and the making of the new more energy efficient thing is way above any savings made by the new one..

    1. Re:Saving elsewhere by Otter · · Score: 4, Insightful
      Sincere question -- why on earth does any one person need more than a laptop, a desktop computer with monitor and one printer at home? (OK, I'll throw in a "media center", also.) Not that one necessarily needs even that, but I'm always baffled by these comments here about home networks that sound more like 15 person businesses.

      Presumably there's an answer, but cross-platform development is the only one I can come up with, and are there really so many people compiling on VMS at home?

    2. Re:Saving elsewhere by timeOday · · Score: 3, Insightful

      If consumer prices more accurately reflected long-term environmental costs, you could answer this question simply by determining whether it made financial sense to replace the gadget. People thinking of dumping their car to get something more fuel efficient in order to save money make this calculation all the time: how much gas $$/mo will I save, how long would that take to pay off the difference between car X and car Y (though the high price of gas is due to scarcity and politics instead of reflecting long-term costs such as the environment). Correcting the fact that pricing does not reflect environmental impact in general is the #1 environmental step we could take IMHO. Granted, this would allow rich people to continue polluting all they want, but at least they'd have an incentive to clean up their factories. And yes, I think we could and should extend this to imported goods.

    3. Re:Saving elsewhere by plague3106 · · Score: 4, Insightful

      Hell, why do you need your own house? Surely an apartment is good enough for you? Even that's wasteful, why not just live in a building with shared bathrooms and beds. Who needs lights at night anyway, or a TV for that matter? Surely not buying a washing machine would be more efficent too, just do your dishes in the sink. Its also a waste to travel, so lets live at where ever we are employed. And you get one plate to call your own. Who needs more than that?

  2. Re:90 whole dollars by eln · · Score: 5, Insightful

    How much money does it cost to save that much energy as well? I kind of scanned the article, but one thing I did notice was that $200 was spent on a new LCD monitor to replace the CRT. If we assume 100% of the energy savings came from that one purchase (which it didn't), it will take more than 2 years to recoup the money spent on that one purchase, and there was no indication that there was anything wrong with the older monitor other than that it used too much energy.

    I would advocate buying newer more energy efficient equipment as your old equipment dies, but I would not advocate going out and replacing perfectly good equipment with more energy efficient (and more expensive) alternatives. It will not only cost you a lot of money, but will also mean more waste from throwing out perfectly good equipment that will likely end up in a landfill.

  3. Re:love to see more of this by pinkocommie · · Score: 5, Insightful

    Craigs List? Or any other classifieds variants. You're making the presumption that both of those are going to waste when in both cases you'll be passing them on to someone else who would've gotten them from another source otherwise (which could be new or used)

  4. Kill-A-Watt by keithjr · · Score: 3, Insightful

    I've got one of these little guys on hand, and I swear by it myself. Much easier than trying to use an amp-clamp to find your AC current usage. Anybody interested in monitoring home energy usages should invest in one.

  5. Re:Only $90/year???? by mdalal97 · · Score: 4, Insightful

    Why not do both? It is not that hard to reduce your consumption. Turn off your computers at night, unplug unused power bricks (for cell phones, cameras, chargers, etc...). It is easy. Just because it appears to be a relatively small benefit, it doesn't mean you shouldn't do it.

    I thought the article was OK, but it did seem like he we dwelling on the 'sacrifices' he had to make... really, how hard it is to turn off your computers when you are done for the day. It is not difficult to make the changes needed to reduce consumption.

  6. The problem implicit: no value for the individual by skoda · · Score: 4, Insightful

    The author spent $200 to buy an LCD monitor to replace a 19" CRT, saving $18 / yr electricity: more than a five year payoff. And he's putting a CRT into a landfill somewhere. There's no economic incentive to buy an LCD; savings are pocket change and doesn't realistically pay for itself. And the environmental cost could be a wash, since the reduced carbon footprint is weighed against a CRT dumped in the trash.

    This article is fun, and I might play a similar game at home. But people chasing $90 in electricity is nearly trite compared to the real energy users: home heating and cooling and clothes washers and dryers. Globally, this is spitting in the ocean compared to the real change that's (presumably) neeeded.

    It's reported that eliminating coal-mine fires (http://freakonomics.blogs.nytimes.com/2007/10/22/from-bagels-to-coal-fires-an-unorthodox-economist-keeps-pushing-for-change/) would reduce CO2 emissions annually equivalent to that produced by all cars and light-trucks in the US. There's little value in individuals replacing 3 W cable modems for 2 W versions when the "easy" targets are still ignored.

  7. Re:love to see more of this by MightyYar · · Score: 3, Insightful

    Parent is very insightful. Also, make sure your old items are recycled, which will at least partially offset the need to mine or pump new materials from the ground.

    When considering cars, there are other things besides CO2 to take into consideration. Older cars tend to emit more smog pollutants than newer cars, so local air quality should also be taken into consideration. Despite the current hype, CO2 is not the only type of pollution in this world. That's why I'm a little bit dubious of Gore when he seems to think that it is okay for his house to use so much energy simply because he buys carbon credits... What about strip-mining credits, mercury credits, sulfur credits, etc.?

    Then again, I still use some of those really inefficient halogen touchier lamps. I use CFL bulbs in the light fixtures that don't dim, but there's something really nice about being able to vary the light from intense and white for reading to warm and dim for movies or dinner.

    --
    W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  8. Re:Watts vs. VA by Smidge204 · · Score: 3, Insightful

    In an AC circuit with inductive or capacitive loads, Volt-Amps does NOT equal Watts.

    To use the common Beer analogy:

    Volt-amps drawn by the device is the size of a beer mug. Watts used by the device is the amount of beer in the mug. VAR (reactive VA) as the amount of foam in the mug. Your Power factor is therefore the percentage of beer in the mug. Problem is, you pay for beer by the mug (1 pint each, say). If you want 3 pints of beer but each mug is 35% foam (PF = 0.65), you pay for 4.6 mugs.

    So, if you have two devices that take the same number of "Watts" then PF=0.65 device is costing you 1 watt but delivering 0.65 watts of performance. If you only need 0.65 watts of performance you can replace it with a theoretical PF=1.00 device that costs 0.65 watts.

    In other words, the two devices in your question must have different outputs (same 1 watt input and different PF) and are therefore not equivalent.
    =Smidge=