DIY Solar Shower Design

Everyday in developed areas, people generate tons of global warming gasses when they burn fossil fuels to take showers. Personally, I’m not against showering every once-in-a-while. In fact, when I go to action gatherings, etc., I sometimes think we would have an easier time getting out of the activist ghetto and connecting with regular folks if a few of us showered a bit more often. I grew up with the “shower every morning” ritual. But with increasing evidence that the burning of fossil fuels is the biggest human threat to the environment — the Center for Applied Biodiversity Science just released a study indicating that up to 37 percent of the world’s species could go extinct by 2050 because of human-cause climate change — I started questioning my upbringing.

First, I started showering less — every 2 or 3 days is really sufficient even when you do physical work and sweat a lot like I do.

But I still didn’t like the thought that my getting clean meant I was connected to a natural gas drilling rig ruining some natural area — and global warming. If you take a 5 minute shower 3 times a week and your shower head puts out a typical 1.6 gallons per minute, you’re using 24 gallons of heated water a week, or 1248 gallons a year. When you figure that heating a gallon of water with gas releases 1 ounce of carbon dioxide, and you multiply by the billion or so people who have developed standards of living sufficient to allow them to shower, you can see that our little showers have a big environmental impact.

It turns out, there is an excellent, non-polluting and abundant alternative to fossil fuels for heating water — low tech solar power. You can use solar power to heat your shower if you have 1-2 hours of sun, which means that folks living anywhere can greatly reduce their use of fossil fuels for water heating by switching to solar. Even if you can only use solar in the summertime, it will change your perspective on using energy. For many folks in the southern part of the country, you can use solar hot water most of the year. If millions of people switched, it wouldn’t be the revolution, but it would help. In fact, since my vision for the revolution is that we would learn how to live in a more sustainable way, switching to solar is a tiny way to begin living the revolution now, instead of waiting for some far off future event.

DIY solar shower design

There are fancy ways to use the sun to heat residential water, but they’re pretty expensive and unless you own where you live, you probably can’t get solar hot water the fancy way. Basically, they involve circulating water through black piping enclosed in an insulated glass-topped box. Sun shines into the box which acts as a greenhouse and gets super hot, heating up the water flowing through it. You need a circulating pump (which can be run by solar electricity), a huge storage tank to store the heated water until you need it, and a lot of pipe from the panels on the roof to the storage tank. Even if you do it all yourself, you’re looking at $2,000 or more just for materials! I think it would be great to install a lot more of the fancy solar hot water heaters, but until then, you can rig up this do-it-yourself system.

Ingredients (get these at any decent hardware store for about $30)

4 1/2 feet 3 inch diameter black ABS pipe

2 3 inch 90 degree black ABS pipe fittings with 2 female ends

2 3 inch 90 degree fittings with 1 female and 1 male end

1 3 inch T fitting with 2 female 3 inch ends and 1 female 2 inch end

1 3 inch T fitting with 2 female 3 inch ends and 1 1.5 inch end

1 2 inch male to 2 inch female threaded fitting

1 2 inch threaded plug

1 1 1/2 inch male to 1/2 inch threaded female fitting

1 1/2 inch ball valve with 2 female ends

1 1/2 inch male to male threaded fitting

1 1/2 inch 45 degree male to female fitting

1 un-restricted, high flow shower head (I use a plant watering can attachment — a hose fan spray attachment would also work — a low flow showerhead won’t work because it requires high water pressure to work, which this system won’t create)

Two bike hooks for your shower stall

Multi-purpose plastic pipe cement

You cut the section of pipe into 2 14 inch sections and 2 12 inch sections and then connect all this stuff together with the plastic pipe cement as show in the diagram. Don’t glue any of the threaded joints — the one on top is for filling and the one at the bottom is so you can remove the shower head assembly for cleaning, etc. What you have at the end of the process is a square of black pipe that holds about 2 gallons of water — enough for a 5 minute shower.

You fill the shower with a garden hose, etc., through the threaded 2 inch hole, and then screw down the threaded plug. Then set it out flat in the sun for 1-2 hours, depending on the air temperature. The black pipe absorbs the sun’s energy and the water inside will get super hot! Then, you screw the two bike hooks into your shower stall (or if you like outside showers, onto the side of your house, etc.) so that you can hang the shower on the wall. Put the hooks high enough so that the shower head will be above your head, but not so high that you can’t actually hang the shower on the wall. Put one hook in slightly above the other, so the thing will hang a little diagonally, with the shower head at the bottom for full draining, and the filling plug at the top so it won’t leak when full.

It will weigh about 20 pounds when full, which might seem heavy at first but you’ll get used to it (and build upper body strength!) I suggest sort of sliding the thing up the wall and then over the hooks.

Before you take your shower, you have to loosen the filling plug at the top so air can get into the shower as it drains. Then, get naked, stand under the shower, and turn the ball joint. The water will run out the shower head and make a really nice shower running just on gravity.

You can fill it in the morning and leave it out all day for a shower in the afternoon or evening, or if you have a good spot that gets morning sun, you can generally put it out the night before and take a mid-morning shower. If you leave it out all day, the water will get too hot to use, so you’ll have to put it in some shade so it can cool down before you use it.

By the way, the shower saves water as well as fossil fuels — about 2 gallons instead of about 8 for a comparable shower. You also save water because most piped in showers require that you run the water while you wait for it to get hot. My shower at home wastes almost as much water waiting for it to get hot as the solar shower uses for the whole shower!

Best of all, having a DIY shower really makes you think about where your shower is coming from, which eventually makes you think about all the energy you use. During the winter when there isn’t any sun, I usually still use the DIY shower. I put a 2 gallon pan over the pilot light on our gas stove overnight and by morning, the water is hot. Have fun getting naked.