Construct a simple, inexpensive rainwater shower system heated with an off-grid solar water heater.
If you collect rainwater, there are a few ways you can use that water beyond giving it to your plants. One way is to build an outdoor rainwater shower. Then, take it a step further by constructing a simple off-grid solar water heater.
Using materials found at my local hardware store, I made a rainwater shower. I crafted a rectangular rack to hold the showerhead using 2x4s and 2x2s. Then I screwed eye hooks into the top that allow me to hang the rack wherever it’s convenient or nail it to a tree. I mounted a low-volume showerhead to the rack, which is attached to a submersible pump with a garden hose and galvanized fittings.
Making an Off-Grid Rainwater Shower System
I use a painted-black 5-gallon bucket to hold the rainwater and pump for the shower. If the water is too cold, move the bucket into the sunshine and let the water warm up for a while. If your rainwater-collection system includes a debris filter, the collected rainwater should be clean enough for showering. If you’re concerned about sanitation, you can add a small amount of unscented bleach to the shower water several hours before you plan to shower. When showering, use biodegradable soaps and shampoos so you don’t contaminate the environment.
I also built a solar water heater to accompany the shower. I built the water heater frame out of plywood I painted black. On top of the plywood, I built a system of CPVC pipes and elbows, painted black, that warms the water. I covered the solar heater with a sheet of plastic to enhance the sun’s effect. I use a small submersible fountain pump to circulate water through the solar heater and back to the bucket via plastic tubing. Once the water is heated and back in the bucket, I can move the bucket next to the shower and swap the small pump out for the larger pump with the garden hose attachment connecting it to the showerhead.
Both the off-grid shower system and the solar heater can function with the use of a 12-volt car battery and a solar inverter to power the submersible pumps.
I spent $118.28 on shower supplies, plus $99 on supplies for the solar water heater, not including the car battery and inverter. Your costs will likely vary, depending on what supplies you have on hand.
Tools and Materials
Off-Grid Shower System
- 2×4
- 2×2
- 17⁄16-inch eye hooks (2)
- Showerhead (1.5 gallons per minute)
- Showerhead pipe and flange
- Submersible pump with garden hose outlet
- Garden hose
- 1⁄2-inch galvanized elbow
- 1⁄2-by-1⁄2-inch galvanized nipple
- 1⁄2-by-1-inch galvanized coupling
- 3⁄4-by-1⁄2-inch brass garden hose adapter
- 5⁄8-inch female hose fittings (2)
- 5-gallon bucket with cover
Off-Grid Hot-Water Heater
- 2×4 sheet of plywood
- Black spray paint
- 30 feet of 3⁄4-inch CPVC pipe
- 3⁄4-inch CPVC elbows (28)
- Metal brackets (EMT straps) (6)
- 2×4 plastic panel
- Fountain pump (90 gallons per hour)
- 16 feet of 1⁄2-inch plastic tubing
- 12-volt car battery (optional)
- Solar inverter (optional)
