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Ideas for collecting back energy

  1. Dec 2, 2008 #1
    While cooking, I noticed how much heat energy is lost using the grill. Isn't there some way to rig up the stove so that the heat from the coils on their underside is collected? Can't stoves be made more efficient this way? If I could, I'd have numerous collectors throughout my apartment. Heck, even the heat from some bulbs should be transferred.

    It looks like there is so much energy lost all around us.
     
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  3. Dec 2, 2008 #2

    Pythagorean

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    thermocoupling, I guess... which is terribly inefficient itself.

    sterling engine would be expensive to build/buy, don't think it would be worth it (don't know if the gradient is enough, even)

    I don't think it would really be that much energy because you lose a lot converting it from thermal to electrical and it's not a lot to start with.

    Up here in Alaska, it may as well stay heat :P it will just reduce (ever so slightly) your heating bill. Might as well not convert it over and back, losing a bunch of the power.
     
  4. Dec 2, 2008 #3

    turbo

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    My wife and I do a lot of baking in the winter. Baked beans, biscuits, roasts and turkeys... We need to make meals, anyway, and the waste heat from the oven can get this little cabin toasty on a mild day.
     
  5. Dec 2, 2008 #4

    Ivan Seeking

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    I realized that here in Oregon, CF lightbulbs make little sense as we can use the excess heat anyway. In reality, we are only saving energy about 3 months out of the year. The rest of the time, the incandescent bulbs help to heat the house.
     
  6. Dec 2, 2008 #5

    Pythagorean

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    It's surprising how much an oven (or incandescent lights in Ivan's case) can contribute to heat in the long-term. I have a friend who turns on his burners and his oven when he runs out of heating fuel!
     
  7. Dec 2, 2008 #6

    turbo

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    We use CF bulbs here, in part because electricity is so expensive. It's a racket. The dams that supply our electricity were all built many years ago, and hydro-power is very cheap. Maine is an exporter of electrical power because of these dams, but somehow the Public Utilities Commission lets the utilities charge us 'way more than people elsewhere on the grid.
     
  8. Dec 2, 2008 #7

    Pythagorean

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    In my hometown, we all "own shares" in our electric company (it's also hydro)
     
  9. Dec 2, 2008 #8

    Ivan Seeking

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    We have cheap hydro power here in Oregon. Even given your arguments that wood heat is environmentally acceptable, it isn't worth it for us, so we're all electric anyway [less emergencies].

    We used wood heat for about twelve years, but what a dangerous pain in the butt! We've had a couple of close calls.
     
  10. Dec 2, 2008 #9

    Ivan Seeking

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    I think the short answer to the op is that it would be too inefficient to try to capture that heat in some usable fashion. It would be cost prohibitive.
     
  11. Dec 2, 2008 #10
    :rofl: Yeah, so I see. Thanks everyone.
     
  12. Dec 2, 2008 #11

    turbo

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    I have gotten ahead of my firewood to the point that I have about a whole year in reserve. Burn short, hot fires with very dry hardwood in a clean-burning stove, and you can't see smoke coming out of our chimney - just a shimmer of heat-based refraction. I haven't had to clean the chimney since we bought this place. I shovel a bit of creosote out of the cellar clean-out every year and look up the chimney with a mirror - I can see the mortar-joints of every flue-tile all the way up. I can't imagine heating with any other fuel at this point. I have an oil furnace in the cellar, but it's only used if I am going to be away for the day in bitterly cold weather. I have used less than 1/4 tank in three years.
     
  13. Dec 2, 2008 #12

    Ivan Seeking

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    If we burn the excess wood from our property, then we would burn a lot of fir. Hardwoods can cost $130 a chord, so at that price, electricity is competitive. And since we don't have a stove with an exterior intake, then we are just sucking cold air into the house when we use the woodstove.

    I must say though, a load of dry oak can produce an amazing amount of power. I once estimated that we were producing about 100,000 watts of heat at full throttle. When we first moved here, before we learned to control the "thermal momentum", we about ran ourselves out of the house one day. It was twenty degrees F outside, we had the windows wide open, and it still was something like eighty degrees in the house!
     
  14. Dec 2, 2008 #13
    do you live on a farm?

    http://www.hedon.info/FuelEfficientCookstovesUsingCowDungCakes
    http://www.repp.org/discussiongroups/resources/stoves/apro/dung/Aprodung.htm
     
  15. Dec 2, 2008 #14

    JasonRox

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    It's not about costs!!! It's about being green!!!

    Kidding.
     
  16. Dec 2, 2008 #15

    turbo

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    I pay $65/cord for good-quality hardwood, cut to length, split, and delivered. I have a hydraulic splitter, and I split the wood even finer than it was delivered because we have a really small stove, and it's easier to control the fires with smaller chunks of wood. Small, efficient fires in a well-insulated house keep us comfortable. I don't tighten my house to ridiculous extents - we have to have some air infiltration to keep the place healthy. I insulate the windows to reduce heat losses, but leave gaps around doors, sills, etc, so that the wood fires can draw in fresh air from the outside. It's a balance.
     
  17. Dec 2, 2008 #16

    Ivan Seeking

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    It is ALWAYS about the cost. If it's not practical and cost effective, then almost no one will use it.

    Also, dollar cost equates in some fashion to energy cost of production. Many technologies are challenged because the energy input to produce the technology or product rivals the liftetime energy production or savings. This is particularly true of ethanol fuel production, for example. It may take more energy to make ethanol [from corn] than we get back from it as a fuel.

    If something isn't cost effective, that can be an indicator that it is not energy effective either. Ethanol production is heavily subsidized.
     
    Last edited: Dec 2, 2008
  18. Dec 2, 2008 #17
    yes, but have you included taxes on the income for wood you sell? if the biomass on your property has enough turnover to provide your heat, you may be better off to burn it.
     
  19. Dec 2, 2008 #18

    Ivan Seeking

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    Heh, Jason, I obviously didn't see your hidden "kidding". But the point is still worth making,
     
  20. Dec 2, 2008 #19

    Ivan Seeking

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    I don't sell wood. And it takes so much work to get the wood off the hill, I can't even give it away. I have about six chords of uncut fir [from two diseased old-growth trees that we had to drop] laying around now. No one will take it.


    When we first bought the place, I liked the exercise, but my feelings about that have changed. :biggrin:
     
  21. Dec 2, 2008 #20
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