Energy of showering

Did you think about how much energy is needed for a refreshing hot shower?

Let us see…

You need to know some input data:

• how much water you use (for example 16 l/min),
• some physical property of water (heat capacity =4200 Joule/kg/Celsius, density = 1kg/l)
• the input water temperature supplied to your heater
• the outlet water temperature what you wish to enjoy to shower with (let me assume ~40 Celsius)
• how long you shower (5 mins in our example)

The heating power your heater must provide is the multiplication of all the parameters and the difference between hot and cold water temperatures.

The energy you will use for the 5 minutes showering is the multiplication of power and time (Energy=Power*Time).

DockCalc makes you the calculation simpler by handling all measurement units in the background, so you can display the results in Watts and Watt-hours without taking care of converting minutes to seconds or hours, watts to kilowatts and so on.

Once you know the energy prices, you can evaluate the costs by simple multiplication:

I just have to mention, the 33.6 Kilowatts of power is a lot. An electric car might need that power to maintain a speed above 130km/h. Think about it when enjoying the hot water!