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bigflamingtaco t1_j4oltp7 wrote

Reply to comment by dogswontsniff in How do non electric heat operated fans work? by ranman12953

How is free fan operation less cost effective than paying for electricity?

I don't think many are expecting tec fans to blast air across the room. Anyone that knows anything about peltier knows you don't get a tremendous amount of power out of them for the same reason they consume a lot of power to cool anything.

Mounting one to my Big Buddy heater is a heck of a lot cheaper than supplying the internal fan with D-Cells, which can't even make it through a single weekend of camping.

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joalheagney t1_j4pbw10 wrote

Because you can just allow more heat to go up a tall, well designed/balanced chimney, at a lower fuel to heat efficiency, than taking that heat, converting it to electricity, then to kinetic energy.

Same overall effect with extra (unnecessary) steps. Chemical PE -> heat (-> electricity) -> kinetic energy -> gravitational PE.

A better overall strategy is mass heater fires, like mass heater rocket stoves, or Scandinavian masonry stoves. Burn a small fire, hot, fast and about 70% efficient. Let the heat soak into a massive thermal mass and allow the heat to slowly soak out into the dwelling.

An even better solution are Chinese fire-beds, where you sleep directly on a very flat, very short stove. Heat the body, not the house.

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bigflamingtaco t1_j4zxrx2 wrote

I don't think we're on the same page here. I'm talking about using a tec fan with a portable propane heater instead of using batteries to run its internal fan, not using tec fans as a solution for all heat distribution requirements. You use tec fans with Mr Heater style propane burners and micro stoves as often used for winter camping. If you're running your buck stove in the living room and want to distribute the heat to the other end of the house, tec fans aren't going to do it.

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joalheagney t1_j51th4w wrote

Ah. The OP was talking about installing a stove so I was thinking like a wood stove.

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bigflamingtaco t1_j5319nn wrote

Sorry, I probably should have been clearer about my transition to small heaters.

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