Three modern, chrome mixers partially submerged in water against a light blue background.

Energy calculator – calculate water and energy use

Replacing a mixer with a more water- and energy-efficient model can reduce the use of both hot water and energy. With Gustavsberg’s energy calculator, you can estimate how water and energy use, energy costs and CO₂ emissions may change when replacing a mixer. The calculations are based on data from sources including the Swedish Energy Agency, Statistics Sweden (SCB) and the Nils Holgersson Report.

The result is an estimate. The actual outcome depends on factors such as the products being compared, user behaviour, number of users, energy prices and how the hot water is heated.

Two people reviewing data from the energy calculator on a tablet.

Lugnt vatten med små, steniga öar och träd, en röd träpanel syns i förgrunden.

Why does the mixer affect energy use?

When you use hot water, energy is required to heat it. The amount of water used and the proportion of hot water therefore also affect energy use.

The mixer’s flow rate and functions can influence the amount of water and hot water used. By comparing different mixers, it is therefore possible to estimate how replacing a mixer may affect water and energy use.

RISE study showed 28% lower hot water use

As part of the RISE project Water use with energy-efficient mixers (2017:11), a field study was conducted in which standard mixers were replaced with more energy-efficient models.

In the study, hot water use decreased by 28% after the replacement. The study also showed that the reduction was maintained throughout the measurement period.

The result applies to the products, households and conditions included in the study and should not be regarded as a guarantee of an equivalent reduction in every household.

Calculation example for a household

SP, now RISE, has also calculated the potential when replacing older mixers with more energy-efficient alternatives.

In one calculation example for a household with two adults and two children, the difference corresponded to approximately 1,680 kWh per year in reduced energy use for hot water.

The impact on cost depends on factors such as current energy prices and how the hot water is heated. Based on an assumed total energy price of SEK 2.86/kWh, 1,680 kWh corresponds to approximately SEK 4,800 per year.

The amount is a calculation example and not a guaranteed saving.

Read the SP/RISE report: Saving potential of energy labelled taps and showers