Solar energy can be used to heat water for washing oneself, as well as washing clothes and dishes; see:
Solar energy can also be used to treat water, to make it safe for drinking, in two key ways:
- Solar water disinfection - disinfection by the heat and UV light (or sometimes just heat) of the sun. The water must be already clear, especially when using the sun's UV light.
- Solar distillation - using the energy of the sun to evaporate the water and then condense it. This is a much more energy intensive process, and requires more specialized and expensive equipment, but can be expected to give even safer water, and can start from even very dirty or saline water.