I recently put solar panels on the house. Well when they calculated my wattage needs they did if off the the energy needs of 2 1k hps and 1- 8" and 2 6" inline fans. Well whilst they were installing them, covid happened. So when my first deposit of Trump Bucks came in, i invested in my ChilLed x5s. Then I talked the wife into letting me get out from under the old school inlines and get a couple of AC infinity with Controller 67s. Now its middle of winter, I got both lights running full power, and my electric bill is $16.78. My solar panel bill is 165 bucks. My average bill before all this was between 280-400 depending on time of year.
Thermal electric wine fridges are great for storing product. No compressor. So they dont rob your humidity. For energy efficiency, peltier still require an electrical charge, fans, ect to work. I saw a peltier cpu cooler that was then ran through a ss wortz chiller coil as a hydroponic water cooler. From what I remember, once they got everything well insulated, with good reflective material it actually worked. I think the issue was that for what they spent building it, insulated everything it would have been cheaper to just buy a chiller.
Im actually planning on a small mushroom tent in my grow room. Mushrooms are cheap to grow, cheap to set up. I dont run a sealed grow but I am also finding im not fighting heat. My idea is that once the mushroom are pinning I can start blooming and the co2 from the tent will give me a nice boost. Maybe it wont and ill just come out with some wonderful homegrown mushrooms. Cant lose.