What is a power tariff and how does it affect electric car charging?

As electricity use increases in everyday life, the demands on the electricity grid are increasing. The grid must cope with the highest peaks in consumption, not just average usage. Since it is costly to expand the grid just to meet short peaks, the purpose of the power tariff is to even out electricity use over the day.

The background is that the Electricity Act, which was decided by the Riksdag and the government, requires that network charges reflect to a greater extent how the electricity network is used. The Energy Market Inspectorate has developed guidelines, but the electricity network companies themselves decide when and how the model is introduced. All major companies have begun the transition but at different rates and with different approaches.

How it works in practice

The electricity company measures your highest electricity usage during the month. This means that even short periods of high consumption can have a big impact on your network fee. If several appliances – such as a stove, washing machine and heat pump – are used at the same time, a temporary power peak is created and the cost increases, even if the total electricity usage during the month is normal.

Different grid companies calculate the power in different ways. Often an average is taken of the three hours when you used the most electricity. The higher the power peak, the higher the grid fee. Two households with the same total electricity use can therefore have completely different costs depending on when and how the electricity is used.

Advice for electric car owners

Charging an electric car can result in high power peaks. Here are some tips to keep costs down:

• Schedule charging, preferably at night when other electricity usage is low.

• Avoid using more power-hungry appliances while the car is charging.

• Charge more slowly. If the car doesn't need to be fully charged quickly, you can lower the power and avoid unnecessary peaks.

• Do you have an hourly rate agreement? Then you can charge when electricity is cheapest and save double.

• Consider a charging box with load balancing, which automatically adjusts charging to the household's other electricity usage.