Photo by the MacAllen Brothers

Showers are overrated. The first step in considering whether to build an outdoor solar heated shower is to take a step back and consider boring old conservation. Shower less and make sure that your domicile is equipped with a low-flow shower head. Not only will you be saving water and burning less fossil fuels to heat that water, but your body odor will soon separate your real friends from superficial hangers-on.

But we urban homesteaders don’t need to be stinky since it’s possible and easy to build an outdoor solar shower. There are two reasons this makes sense, particularly in a place with as warm a climate as LA. First of all, you can direct the water straight into the garden and in so doing irrigate some plants and keep that water from uselessly running down the sewer line. Secondly, placing the shower outdoors makes rigging up a solar heating system somewhat easier and less expensive. Of course, the solar heating part isn’t completely necessary, and it’s possible to run the hot water line out into the garden, especially since you don’t need to worry about the pipes freezing here in sunny LA. One thing to remember–however you rig the shower, make sure to keep the water directed away from your foundation.

Let’s say you’re ready to build your own solar heated shower and you’ve overcome your fear of being nude under the all seeing eye of LA’s police and media helicopters, what we like to call our “ghetto birds”. We’ll start with the most simple solar shower designs and proceeding to the deluxe models.

First off is the camping shower in a bag concept. The principle is simple–you fill a black bag with water, leave it out in the sun, and hang it somewhere for your very brief shower. We’ve not tried one of these things, but we suspect that the result would be less than luxurious, and after all, part of the reason to bathe is the relaxation it offers. But, for the mortifier of the flesh out there, one of these things might just suffice. They are certainly cheap at around $18. If you are really cheap, you can improvise the solar bag shower by filling a car inner tube with water and leaving it out in the sun.

A variation on the bag shower can be constructed out of inexpensive black ABS pipe. Basically you construct a square out of pipe, put water in it and let the sun heat it up for a few hours. Your shower lasts as long as the amount of water contained in the ABS pipe. Plans can be found here. ABS is easy to work with, and this particular design could be scaled up for longer showers. SurviveLA will run some experiments with this design and let you know about the results.

In terms of other do it yourself options several folks have experimented with simply coiling up a length of black garden hose on the roof. A nice example can be found here, and also at the Path to Freedom. The problem with this approach is that when the water is out of the hose, that’s the end of your hot shower.

A more advanced DIY solar shower that resembles commercially available (and expensive) solar water heaters can be made by constructing a glass covered collector box containing a manifold of copper pipes that feed into a used water heater. Hot water contained in the copper pipes in the collector box rises up into the water heater that is kept above the level of the collector. Hot water rises just like hot air and the cold water from the tank sinks back into the collector thus forming a circulation loop–this phenomenon is known as thermosiphoning. Some plumbing skills, are necessary, but it’s relatively easy to learn how to sweat copper pipe. We’ve used a system like this provided by the National Park Service on SurviveLA’s trip to Santa Rosa Island. The nice thing about storing the water in a tank is that you can take a shower well after the sun goes down. Plans for this project can be found on the Mother Earth News website.

Whatever approach you try, the key thing is to keep the costs down and to use as many found materials as possible. The water and gas savings per year are minimal, so in our opinion it does not make sense to buy expensive commercial outdoor showers (like the one made by Hammacher Schlemmer) when you can make something yourself.

An excellent roundup of DIY solar projects including water heating can be found at Build It Solar.

Here’s the truth, I’m lazy. So when it comes to the aforementioned greywater strategies such as bucket flushing and siphoning, while we might try them for a while we’ll most likely quickly tire of all the repetitive effort barring some apocalyptic water shortage. SurviveLA agrees with Art Ludwig, author of Create an Oasis with Greywater that the best greywater systems are the simplest, and involve the least amount of effort and maintenance.

One of the easiest and more permanent greywater solutions is simply rerouting your shower straight out a pipe and into the garden. Here’s how to do it:

1. Confirm that your shower is higher than the point you are watering. The minimum fall for waste pipes is 1/4 inch per foot — any less and you’ll risk a backup.

2. Cut the waste line from your shower, making sure that you are cutting the pipe before the point it meets up with anything coming out of the toilet. Remember you don’t want blackwater in your garden. If possible (i.e. if easily accessible via a trap door or some other configuration), install a three way diverter valve like the one pictured above, so that water can be shifted back to the sewer, if needed, such as during a long rainy period. Keeping the minimum fall rate in mind, run the pipe out to where you want to water.

3. Choose plants whose watering requirements match the amount of water coming out of your shower. To do this you’ll need to estimate how many showers and how much water you use per shower. Odds are it will be water hungry plants such as banana trees.

4. Create a mulch basin around the plants you are watering. The mulch could be gravel, wood chips or leaves. The mulch basin has multiple purposes – it slows the flow of greywater, preventing runoff and it stops greywater from forming stinky pools. Mulch also prevents contact by kids and pets and helps keep down the mosquito population.

5. Some precautions – put a screen over the end of the pipe to prevent rats and other critters from climbing up the pipe and surprising you in the shower. Keep the destination of the pipe well away from your house’s foundation, especially if you have clay soil.

So it’s back to greywater today with a tip on siphoning your bathtub water. The concept goes like this. When you take a shower keep the plug in. Yes it’s a bit gross at first, but you get used to it. When you are finished, submerge a length of tubing in the bath water. Hold your finger over one end and pass it to an accomplice waiting outside in the garden. As long as your bathtub is higher than the part of your garden being watered, you will have created a siphon and the water will drain out of the tub.

Now if this sounds like a pain in the ass, or if you have no accomplices there is (or perhaps was as the website does not seem to be working) a siphon device on the market for just this purpose. Called the “Ban Beater” this siphon pump was being sold in the UK as a result of the draught that struck south-east England this year. However, this greywater siphoning tool is on the expensive side and it’s hard to justify spending a lot of money just to save a few cents worth of water, especially when the siphon devices themselves are produced with plastic and other petrochemical products. Devices like these suddenly become popular when governments institute water rationing as did the British earlier this year. There are less expensive siphoning devices available in hardware and auto parts stores made for siphoning gas, but SuviveLA has not tested them yet.

If siphoning is too much effort for ya, it’s time to move on to more permanent solutions involving rerouting your plumbing that we’ll get into in subsequent posts.