this post was submitted on 21 Sep 2026
12 points (87.5% liked)

Gardening

6882 readers
154 users here now

Your Ultimate Gardening Guide.

Rules

  1. Be respectful and inclusive.
  2. No harassment, hate speech, or trolling.
  3. Engage in constructive discussions.
  4. Share relevant content.
  5. Follow guidelines and moderators' instructions.
  6. Use appropriate language and tone.
  7. Report violations.
  8. Foster a continuous learning environment.

founded 3 years ago
MODERATORS
scarabic@lemmy.world
sabbah@lemmy.world
ManamaKhan@lemmy.world
Spacebar@lemmy.world
Bitswap@lemmy.world
12
Why does no one seem to use peltier elements to heat small greenhouses? (feddit.org)
submitted 1 week ago* (last edited 1 week ago) by viertesauge@feddit.org to c/gardening@lemmy.world
24 comments fedilink hide all child comments
 

Genuine question. When I look up options for heating greenhouses its either propane, kerosene or electricity. So if you dont want to use fossil energy for any reason, why not use peltier elements which would boil down to resistive heating and moving heat from the outside to the inside?

Is it because they dont last in the weather? Or because they require a DC source? (couldnt you simply move the PSU inside the greenhouse and use any conversion losses as additional heating?) Or maybe its because you would have to possibly cut a hole in your greenhouse walls so that the peltiers cold side is actually on the outside?

you are viewing a single comment's thread
view the rest of the comments
[–] viertesauge@feddit.org 1 points 1 week ago* (last edited 1 week ago) (1 children)

thanks for the wall lol. yeah like another user and I said in my other comment the actual reason is probably marginal gains even if you can get it to work.

heat dissipation is solvable with a cpu heatsink and temperature sensitivity probably isnt that relevant in this application if all you want i to protect the greenhouse from frost for example, but thermal leaking might be a problem.

[–] zarathustrad@lemmy.world 2 points 1 week ago

It's possible future advances in materials science (the conducting alloys and heatsinks) could increase the efficiency but those are the major barriers in my non-expert opinion.

Commercial Bi₂Te₃ modules sit around ZT ≈ 1.0–1.2 at room temperature. Active research is pushing this closer to 2, but not at practical temperatures yet. (ZT is not the same as COP but it does directly relate to it for the purposes here. Even at ZT = 2, the COP gain for a heating application is modest because the device still must reject the pumped heat plus all Joule losses on the hot side.)