The obvious energy-saving tip is: Especially on hot summer days, just don’t take a shower that hot. Even if the cool water in the morning is not for everyone, you can save: If you reduce the basic temperature of your hot water, which is controlled by an electronic instantaneous water heater or under-the-counter storage tank, to 60 degrees, you will spend around ten percent less on energy costs per year.
What initially sounds like a loss of comfort is usually not at all. Because the 60 degrees refer to the preset maximum temperature. It shouldn’t be less, because at these temperatures harmful bacteria, legionella, die off. The actual bath and shower water, which we perceive as pleasantly warm to hot, has a maximum body temperature of 40 degrees.
By the way, if you can do without turning it up: homeowners with a gas heater can spend 35 euros less on energy and 85 euros less with electric heating if they wash their hands with cold water (in a three-person household for five times a day wash your hands with two liters of water each day).