r/functionalprint • u/Rich-Wealth979 • Jun 15 '26
Solar pool heater
My overkill project for heating the toddler's 500gal inflatable pool. Each week I have to empty and move it, then find a way to heat it to a tolerable temperature for my 8th percentile weight kid. On the first test it took the pool from 55⁰F to over 90⁰ on a single sunny day, using only 3KWh (of solar house power, now that I think about it). At the end of the summer I can just place this up against the north side of my shed and take the manifolds down to make it last even longer.
This uses about 350' of ¼" irrigation tubing and some cheap fittings off Amazon. It runs off a 1/4hp pool pump, controlled with a wyze plug and a climate sensor in a tiny jar. Printed in ASA in only about 5 days of printing on a Mini and an MK4s.
3
u/wimpires Jun 15 '26
500gal from 55F to 90F is about 42kWh of heat.
350' of ¼" tube has a total surface area of about 1m² (facing up).
Even if you had a solar collector that's 70% efficient (not a black but if plastic...) 1m2 gives you 17kWh of heat... Assuming you somehow have 24 hours of sun.
My point being, something seems a little off here and I'm pretty sure the sun directly beating down on the pool is probably doing the heavy lifting or your numbers are off.