Turning sunlight into hot showers: best kits or hacks?

Not knocking the glass frame idea - definitely clever - but I’ve always been a little wary of any setup that’s heavy or awkward to move. I get that it keeps the gunk down, but for me, the hassle of shifting a big glass panel just isn’t worth it. Plus, I’ve seen what happens when someone drops one of those old shower doors... not pretty.

If you’re worried about algae and smells, I’ve had good luck with just using black poly tubing coiled up on a pallet and covered with a cheap clear tarp. It’s not as efficient at holding heat as glass, but it’s way lighter, and you can just roll it up if you need to move it. For cleaning, I run a bit of hydrogen peroxide through every month or so - no bleach, no vinegar smell, and it seems to keep things from getting slimy.

I guess it comes down to how much you want to tinker versus how much you want to lift. I’d rather swap out a $20 coil than risk my back or a trip to urgent care.

That’s a good point about the weight - glass panels always make me nervous, too. I’ve seen one shatter in a garage and it was a nightmare to clean up. The poly tubing idea sounds way more practical, especially if you’re moving stuff around or just want to experiment. Have you noticed much difference in water temp compared to glass? I’m curious if the tarp makes up for the lower insulation or if it’s just “warm enough.” Also, does the hydrogen peroxide ever mess with the tubing over time? Just wondering if it makes the plastic brittle or anything.

I actually switched from glass to poly tubing last summer after a cracked panel left glass everywhere in my driveway - total headache. With the poly, I did notice the water doesn’t get quite as hot as it did with the glass setup, especially on cloudy days or late afternoons. The black tarp underneath helps a bit, but it’s more “pretty warm” than “steaming hot.” Still, it’s enough for a decent shower and way less stress about breakage.

About hydrogen peroxide - I’ve been adding a splash every week or so to keep algae down. Haven’t seen any brittleness or clouding in the tubing after a full season. Maybe if you went heavy with it, but at low concentrations it seems fine. If anything, the sun does more damage over time than the peroxide. I just try to coil the tubing up when not in use to keep it out of direct sun as much as possible.

Can definitely relate to the stress of glass - had a similar disaster with a solar water heater years ago. Poly tubing is a lot more forgiving, even if it doesn’t turn your shower into a sauna. I’ve found wrapping the coils tighter and stacking them in layers (sort of like a big coil cake) helps bump up the temp a bit, especially if you throw another black tarp over the top when the sun’s out. Still, you’re right, on cloudy days it’s more “lukewarm encouragement” than “spa day.”

I’ve been cautious with additives like peroxide too. A little goes a long way, and I’d rather clean out the tubing every few weeks than risk it getting brittle. UV from the sun seems to do most of the aging anyway - mine starts to get that faded look after a couple seasons no matter what. If you’re handy with a staple gun, tacking up some shade cloth when it’s not in use keeps things from getting cooked. Not fancy, but hey, it saves money for better shower soap...

I’ve wondered about the peroxide thing too - seems like it could be more trouble than it’s worth if it starts breaking down the tubing. Have you tried any of those UV-resistant poly tubes? I’ve seen some rated for longer outdoor exposure, but not sure if they actually hold up better. Also, curious if anyone’s managed to get decent temps on a partly cloudy day without going full greenhouse mode... is there a trick I’m missing, or is that just the limit with these setups?