On a much simpler level, one can purchase or (if so inclined) build a portable solar shower that provides enough hot water for an individual to take several showers. This is the design that lends itself well to use for camping, and the compact design and inexpensive construction also make it ideal for distribution to families in areas which are in need of such a necessity. My portable shower closely follows the design of a commercially available system, consisting of a collapsible bag (obtainable at any camping supply store) that holds 5 gallons of water, connected to tubing that has a conventional showerhead (from a local hardware store) affixed at the end. The bag was painted black with elastomeric paint to provide flexibility, but this turned out to be a less than ideal solution, as the paint did not adhere to the plastic material of the bag.

Possibly a more conventional paint might have better results, or a rigid-sided container might be substituted. The bag has a nozzle to which plastic tubing (also sourced from a hardware store) can be attached. The nozzle also functions as an on/off lever for water flow, which is dependent on gravity -- the bag must be placed higher than the showerhead when the shower is in use for the water to flow down the tube. To ensure maximum exposure to the sun, I constructed a reflector out of cardboard coated in typical kitchen-use aluminum foil, based on a design for a solar cooker. The reflector is collapsible (enhancing the portability of the system), and stays in the open position with the assistance of some velcro fasteners. The bag is placed within the reflector in an area where it will be exposed to direct sunlight for at least 2-3 hours. After several hours the temperature of the water should be somewhere in the range of 100 degrees Fahrenheit, suitable for a comfortable shower. The five-gallon capacity allows either one long shower or several short showers.

Assembly of the shower itself is minimal -- the bag is a pre-assembled unit, requiring only the attachment of the tubing on the nozzle to provide water flow. The showerhead was attached to the tube with a friction connector, which has threading on one end to mate with the showerhead. Once completed the bag has a hook system that allows it to be suspended at height using an S-hook to make use of gravity. The amount of time spent on assembling the shower components amounts to no more than about 1-2 hours at the most. More time-intensive is the construction of the reflector, which involved several hours of figuring out the best way to fold the cardboard and then gluing and taping the foil material onto the cardboard. Total cost for this portable system is minimal when compared to a more permanent setup -- figure about $20-25 for all the materials necessary to build your own portable solar shower.

A commercially available system can typically be had for less than this over the internet or at a camping supply store, so it's really a matter of whether or not you want to take pride in knowning that you built your own. The reflector, of course, is not a part of the commercial system, so that would have to be built as a separate component. While building your own portable solar shower isn't likely to save the world, if society made a collective effort to use solar energy we could reduce usage of and dependance on fossil fuels. The portable solar shower is an example of technology that is readily available at an inexpensive price, making it a good choice for use in lesser developed countries.