Its similar to the people why try to chill water with a dorm refrigerator, the power costs far outweigh the benefit.
You are right there is a question of "is it worth it?", but this is not to say it won't work. :smile: Those dorm fridge chillers do work, at least in the elemental sense...as do the "bucket heaters" for RO.
If you're on city water where your waste line just gets recycled back into the municipal water treatment system, then aside from initial cost of the water (which is usually insignificantly cheap) there isn't really any "waste". To me it would be a little hard to justify running "bucket heater", but that does depend on how often/for how long the heater cycles on.
However, your feelings may vary if you're on well water (or other source where there are higher "acquisition costs") and there's not a good recycle option for all that waste water. A rain barrel - or a few - outside coupled with a soaker hose would make great use out of a lot of it. In this kind of scenario a "bucket heater" may actually be worth it, but it's also possible a zero waste system or at least a booster pump may be variously better and more economical in the long run.
Just to throw it out there, I've thought about scavenging waste heat from my ridiculously inefficient MaxiJet saltwater mixing pumps by coiling the RO tubing in the salt mixing vat. Never measured it, but my mix water is always
warm.
I don't suppose there's any reason this idea couldn't extend to be a "coil chiller" when you wind the RO tubing around inside your sump? :xd:
Of course, if your system doesn't need a chiller already, you're just going to be running a "rectangular bucket heater". LOL
Good luck!
-Matt
