[HN Gopher] Thermoelectric Stoves: Ditch the Solar Panels?
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Thermoelectric Stoves: Ditch the Solar Panels?
Author : Shared404
Score : 10 points
Date : 2020-09-05 18:33 UTC (4 hours ago)
(HTM) web link (solar.lowtechmagazine.com)
(TXT) w3m dump (solar.lowtechmagazine.com)
| jacinabox wrote:
| Wood burning contributes unnecessarily to deforestation and emits
| a lot of air pollution, things people used to think were no
| bueno.
| magicalhippo wrote:
| My cabin, which was put up by my grand parents, has a picture
| of the view back in the 50s. When comparing it to the view
| outside today it's easy to see the treeline has moved up
| hundreds of meters in altitude. Mountains that were bare are
| now part of the forest.
|
| Not saying we should promote wood burning, but I'm not tossing
| out the old wooden stove.
| m463 wrote:
| I thought it was thinner air that caused the treeline, is it
| temperature?
|
| or is it air, which just has more CO2?
| throwaway5752 wrote:
| It's temperature. Which, of course, is because the air has
| more CO2.
| Ma8ee wrote:
| Temperature. The tree line moves down the further north you
| go.
| millstone wrote:
| Wood pellets are efficient, produce low pollution, and are one
| of the most renewable fuels.
| dr_dshiv wrote:
| Mind blown. Yet, Life Cycle Analyses show conflicting
| results. Here is a recent review. Would be very good to know
| whether this has potential as a future biofuel.
|
| https://www.sciencedirect.com/science/article/pii/S136403212.
| ..
| gpm wrote:
| Thermoelectrics generate power by allowing heat to flow from a
| hot area to a cold area. Almost certainly you would be better off
| efficiency-wise by putting insulation in place of the
| thermoelectric element and generating electricity in a central
| steam power plant (fueled with the fuel you save via the
| insulation).
| ChuckMcM wrote:
| I chuckled at this: _" With appropriate stove design, the heat
| from electricity conversion can also be re-used for cooking or
| domestic water heating."_
|
| Except that thermodynamics gets in the way :-). The heat that is
| converted into electricity is, electricity. So it is no longer
| part of heat available for heating. If you did have 100%
| efficient thermoelectrics they would be pretty neat since you
| could put as much wood or fuel into your stove as you wanted and
| the surface of the stove wouldn't change temperature at all, but
| there would be electricity available!
|
| That said, using thermoelectric conversion to charge your cell
| phone when camping[1] (and using the fire for toasting
| marshmellows) is a win :-). But it isn't going to replace solar
| any time soon sadly.
|
| [1] https://gazettereview.com/2016/06/powerpot-after-shark-
| tank-...
| yodelshady wrote:
| Saving you a click - "it's efficient if you count waste heat as
| useful".
|
| As a rule of thumb, a good PV panel and a good thermal engine
| will give you similar efficiencies - a little under 20%, more if
| you want to spend lots, but really very tricky to exceed mid-30s.
| A thermoelectric generator, quoted as "1/3rd as efficient as PV"
| - sounds about right, so maybe 6%.
|
| PV panels consume land. A wood-fired generator as suggested would
| need _at least_ 10x the land to grow the trees for the same
| energy input, even _forgetting_ the difference in efficiency.
| Probably closer to 100x.
|
| Oh, and PV works in literal deserts, where land is cheap, because
| it's useless to grow food or as a reserve, so you're sacrificing
| nothing!
|
| The closest practical variant of this is district heating with a
| _regular_ fossil- or nuclear- turbine generator. IIRC, a few
| towns in Russia have genuinely too cheap to meter heat because of
| this.
| m463 wrote:
| I think the article is worth the click, even if just for the
| soviet history.
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