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Measuring the Energy You Use?

centdollarman asks: "Everyone keeps talking about how energy is being wasted here and there. Energy bills keep soaring for me, and now I'm back to paper and pencil: just taking notice of the power meter values. Mine is nice, as it has a cute LED that blinks at 1/1000 of a KWh. However, there has to be a better way to do this, and I've started searching the web for someway to count my usage, automatically. Of course, this is easier said than done. It would also be nice to have some way to (cheaply!) measure the power consumption of a single device." So, for the energy conscious among us: how are you measuring the power you use?

7 of 184 comments (clear)

  1. For an individual device by keithmo · · Score: 4, Informative
    1. Re:For an individual device by djmurdoch · · Score: 3, Informative

      The Kill-a-watt has a pretty bad user interface:

        - It is big, so it blocks both parts of a duplex receptacle if you plug it in directly. Use it on a small extension cord.

        - It is powered by the source you plug it into, with no retention of results when unplugged, and no light on the display when in place. Bring a flashlight and/or a longer extension cord if you're using it behind an appliance.

      But in a well lighted location, it is quite informative.

    2. Re:For an individual device by subreality · · Score: 4, Informative

      That's why we have the Watts Up Pro: http://www.thinkgeek.com/gadgets/electronic/7acf/ . It even has an RS232 interface. But it's relatively expensive.

      I have a Kill-A-Watt, and it has all the problems you mentioned, but it also does everything it promised to do, for cheap. I'm quite happy with it.

  2. Datacentre by IckySplat · · Score: 4, Informative

    The Datacentre we have our kit in has these small LED based ammeters on each of the power strips.
    Very handy for figuring out where our power budget is going.

    Google provides the following in quick order
    http://www.energyoptimizersdirect.co.uk/acatalog/E nergy_Devices.html?gclid=CJ2il5S3r4cCFTpsEAod3n1L- Q
    http://www.blackbox.com/Catalog/Detail.aspx?cid=18 3,1324,1328&mid=4084

    Enjoy :)

    --
    Help! help!, the termites are eating my DRAM!!!
  3. well, by joe+155 · · Score: 4, Informative

    I agree with some other comments about conserving energy as a good way for going and stopping your bills from going up... as for a way of measuring you can see that kill-a-watt device some people have shown, it seems like a good idea. One issue is that it doesn't really tell you how much power things like lights and your oven use though (because they don't have standard plugs - at least not here).

    The only way I can think of doing that, although it would be a hastle, would be to switch off all items in your house and verify that with your little light not blinking, then switch your oven on and time how long it takes you to use a Watt/hour. Then switch that off and see about the lights you would normally have one. This would give you some ideas on how much these things use. As a way of reducing the amount of power that they use you could get energy efficient bulbs (they cost more innitially but less in the long term) and if you need to replace your oven you can look for the most energy efficient one you can find (and if gas or electric is cheaper in your area angle your purchase towards that).

    There are also good savings to be made by changing your fridge/freezer and your washing machine to something more efficient (If you live in England we already have a rating service for these, buy only A rated things and you'll save - if not then you'll have to do some investigating on your own)

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    *''I can't believe it's not a hyperlink.''
  4. Re:cheaply measure a single device by Myself · · Score: 4, Informative

    I love my kill-a-watt but I've been thinking of picking up a Watt's Up? for the datalogging capabilities. But the price is silly, I should just build one.

    Anyway, a clamp-on ammeter should be in your toolkit. (Get a DC-capable model and watch motherboard/peripheral power draw inside your PC!) Instead of slicing open an extension cord, consider an AC line splitter to make your measurements with. The 10-winding side makes small measurements more accurate, and it looks more professional if you end up using it on the job.

  5. But I know the culprit by Coppit · · Score: 4, Informative

    For my house, A/C is by far the biggest chomper of energy. During the summer months my electric bill gets as high as $270, and during the winter it gets as low as $70. Not only that, but on hot (97 degrees f) days my upstairs never gets cooler than about 78f.

    It's a fairly new house, so I can't simply replace the upstairs unit, but I think it's clear that they didn't install a large enough one. What can I do? Put another powered roof ventilator in? Add more insulation in the attic? Put a radiant barrier on the underside of my roof?

    This website helps to answer these questions. It provides some analysis of the different scenarios. Dunno if the analysis is accurate or not...