I hiked the Colorado Trail, all 468 miles at the time. Its been rerouted a little so its somewhat longer. Do it if you get a chance. Its a marvelous above treeline experience.
Nearing a resupply point, we came upon a trail crew by Copper Mountain. They invited us to stay for supper, enjoy a hot solar shower and spend the night. We accepted and had a great time of companionship. The shower held five gallons, and was plenty warm. Amazing experience. Many thanks to the Colorado Trail crew for their generosity.
Today I bought a solar shower made by Coleman. Surprisingly it only cost $7.88 at Walmart. Holds 5 gallons, and the directions say it takes about 3 hours to heat.
I have plans to use it for outdoor showers this summer, washing dishes, and basically have it for base camping.
This heat wave we've been going through made me think of turning this "lemon" into lemonade by utilizing the constant sunshine. I have it laid across the trunk of my Geo, a naturally hot spot anyways.
The red shower end is adjustable. I'll report back after more testing.