Turning sunlight into hot showers: best kits or hacks?

Title: Turning sunlight into hot showers: best kits or hacks?

Yeah, the peroxide thing is a bit of a double-edged sword. I tried it once because I was worried about algae, but after a season the tubing got all brittle and started leaking... not worth the hassle for me. I switched over to some black UV-resistant poly tubing (think it was labeled for irrigation use), and it’s held up way better than the clear stuff. Still gets a little faded after a year or two, but I haven’t had it crack or anything yet. Not sure if it’s truly “UV-proof,” but it’s definitely less maintenance.

As for the partly cloudy days, that’s been my biggest frustration too. I’ve experimented with wrapping the tubing in those cheap emergency blankets to reflect more light back onto it, but honestly, the gains were pretty minimal unless the sun was really out. One thing that helped a bit was coiling the tubing tighter and putting it on a dark metal sheet—seems like the extra mass holds heat longer, so you don’t lose temp as fast when clouds roll in. Still, without a greenhouse or some kind of insulated box, I think there’s just a limit to how much you can squeeze out of these setups.

I’ve seen some folks build little mini-greenhouses just for their coils using old windows or even clear storage bins. Looks goofy, but apparently it helps trap enough heat to make a difference. Haven’t gone that far myself yet... I keep hoping for a hack that doesn’t involve building a whole sunroom just for hot water.

If anyone’s managed to crack the code for decent temps on those in-between days without going full DIY greenhouse, I’d love to hear about it. Otherwise, I guess we’re all just at the mercy of the weather gods. At least the cold showers build character, right?

Yeah, I’m with you on the peroxide—tried it once and my lines turned to mush by the end of summer. Black irrigation tubing is definitely the way to go, though I wish someone made a truly UV-proof version that didn’t cost a fortune. I’ve also played around with those “solar shower” bags, but honestly, they’re just not practical for daily use if you want more than a quick rinse.

On the cloudy days, I’ve had slightly better luck using foam board insulation under the coil and then covering it with an old glass door. It’s not a full greenhouse, but it traps enough heat to keep things warm-ish even when the sun dips behind clouds. Still not perfect—if there’s no sun at all, you’re out of luck—but it beats shivering every time a cloud rolls by.

Honestly, unless you’re willing to go all-in on a proper collector box or evacuated tubes (which gets pricey), there’s always going to be some compromise. At least we get bragging rights for doing it ourselves...

I get the whole “there’s always a compromise” thing, but honestly, I think people overestimate how much you need to spend for a decent collector box. I built one out of scrap plywood, some leftover insulation, and a busted window I found on the curb. It’s not pretty, but it gets the water hot enough for a real shower—even on days when the sun’s just peeking through. Sure, it took a weekend and a few curse words, but it beats fiddling with those solar bags or shivering under lukewarm water. Sometimes DIY doesn’t have to mean settling for “good enough.”

“I built one out of scrap plywood, some leftover insulation, and a busted window I found on the curb. It’s not pretty, but it gets the water hot enough for a real shower—even on days when the sun’s just peeking through.”

That’s actually pretty inspiring. I keep seeing all these fancy kits online with price tags that make my wallet sweat, but what you did sounds way more doable. Did you have to worry much about leaks or pressure? I always wonder if those DIY collector boxes can handle any kind of decent flow, or if it’s more of a trickle. Also, how did you connect it up to your shower setup—just gravity-fed, or did you rig up a pump?

I get what you’re saying about “good enough”—sometimes the homemade stuff ends up working better than the store-bought gadgets, at least for certain things. My uncle once made a solar heater out of black-painted copper coils and an old glass door, and it got so hot he had to mix in cold water just to keep from burning himself. Not sure I’d go that far, but it goes to show you don’t always need fancy materials.

One thing I’m curious about: does your setup hold heat well into the evening, or does it cool off pretty quick once the sun dips? I’ve read insulation makes a big difference, but never tried building one myself. Also, any issues with freezing if you leave water in there overnight?

Honestly, I’m tempted to try something similar. The worst part of camping for me is always those sad little solar bags that barely get lukewarm unless it’s July and there’s no wind. Your approach sounds like a solid upgrade—might not win any beauty contests, but who cares if it works?

I get the appeal of DIY, but honestly, I’ve seen a lot of these homemade setups end up leaking or losing heat way faster than folks expect. Even with insulation, plywood and scrap windows don’t hold up long-term—especially if you’re actually running a shower, not just filling a bucket.

“sometimes the homemade stuff ends up working better than the store-bought gadgets”