Where sunshine is scarce, you can always boil your water on the fire (rustic and charming, but terribly time consuming), or you could use a gas-heated handheld shower.
Newer models are surprisingly compact, transforming you from camper to glamper with the twist of a dial. Some are stand-alone appliances, while others consist of a water cylinder and shower extension that attach to any gas cooker.
Water heats up quickly (up to 3,5 litres a minute) and the generously sized showerhead gives an all-over clean.