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Electricity from steam at home?

  1. Sep 7, 2011 #1
    The idea I have is that on a multi fuel stove I could have a boiler attached to it to heat water for the purpose of steam, then the steam in turn to drive a small steam turbine to produce electricity and the steam then to condense and return to water. Thus allowing the process to start again??

    So is there anyway this is done, or can be done on a domestic scale?

    Please bear in mind that I'm not an engineer or a physicist. I'm just a guy with an idea???
     
  2. jcsd
  3. Sep 7, 2011 #2

    russ_watters

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    Yes, it certainly can be done, but why would you want to? It is dangerous and unlikely to save you any money.
     
  4. Sep 7, 2011 #3
    I guess the goal is to have all home energy coming from burning wood? If you live deep in the woods, this makes sense. Trees block wind and sun, thus disabling the option for renewable energy (assuming there is no nearby stream to stick a turbine in). And, such a location makes fuel delivery very expensive. What's left? Trees to burn like crazy!
     
  5. Sep 7, 2011 #4

    Drakkith

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    You might want to look into a Stirling Engine instead of a boiler. Boiling water takes a lot of energy for the amount of expansion you get I believe. Using compressed gas instead might be more efficient.
     
  6. Sep 7, 2011 #5

    Pengwuino

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    Yup as others have said, it will work but why? The gas/wood you use from the stove will be far far more expensive than whatever you're hoping to use the electricity to save money for.
     
  7. Sep 8, 2011 #6
    Well as my stove is running all through the winter, it's not as it is going to cost me any more to run? And I thought if it I could use it to produce some energy it would ease my out goings during the winter?
     
  8. Sep 8, 2011 #7

    Drakkith

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    Sure, you could use the exhaust heat to power a heat engine to run a generator. However I don't think you will be able to boil water very well with your setup, so I would suggest using something like a Stirling Engine.
     
  9. Sep 9, 2011 #8

    russ_watters

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    Unless you are only recovering exhaust heat, converting heat to electricity means less heat available to heat your house(so you'll have to increase your fuel consumption). And if there is a lot of wasted exhaust heat, it would be easier, safer and cheaper to try to recover it as heat.

    Is the furnace fan forced draft? From outside? Does it have an exhaust heat exchanger? If the answer to these questions is no, then you are sending at least a quarter of your usable heat up the stack while simultaneously pulling cold outside air into your house. Adding a combustion air supply fan and exhaust heat exchanger could legitimately reduce your fuel costs by a third while simultaneously reducing drafts.

    Could you give us more details of the stove?
     
    Last edited: Sep 9, 2011
  10. Sep 9, 2011 #9
  11. Sep 9, 2011 #10
    Yes, it will cost you more. If you're using it to heat your house, the fuel will cost you x. If you use it to heat your house and boil water for your steam cycle, it'll cost you x + y.

    As someone remarked, you might extract heat from the gases going up the flu to be used in a Stirling engine. Your extractor will gunk up rather quickly, though.
     
  12. Sep 10, 2011 #11

    Borek

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    Google thermophotovoltaic cells.
     
  13. Sep 11, 2011 #12
    http://www.oekofen-usa.com/" [Broken] (in German). They will be using a Stirling engine, btw.
    So far they´ve only started testing.
    There´s a website for the project http://www.okofen-e.com/en/index.html" [Broken], but the English translation is not online yet.
     
    Last edited by a moderator: May 5, 2017
  14. Sep 12, 2011 #13
    These guys already have one on the market, so that at least proves something.

    http://www.whispergen.com/

    The basic idea may be relevant to you Leejay - use the high temperature heat to run a generator, then use the low temperature exhaust to heat the hot water for central heating/showers. You don't need high temperatures to heat a house, but you do to generate electricity with any efficiency. It doesn't matter how inefficient the generator is because all the waste heat is used productively.

    In principle you could generate electricity in the home more "efficiently" than a power station, because you can make use of the waste heat while they have to dump it.
     
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