Changing the timing of electricity use in buildings reduces peak demands on the grid, according to a new analysis focused on Norway and its connection with the broader European power system. Ultimately, this strategy could save money by reducing the need for costly new power infrastructure.

Renewable energy sources such as solar and wind are becoming more important in the European power grid. At the same time, more aspects of daily life such as cars and building heating systems are going electric. In turn, this is sparking a greater need for flexibility in power use to accommodate fluctuations in renewable energy supply.

Flexible power use means tapping more electricity—such as to charge one’s car or do a load of dishes or laundry—when lots of renewable energy is available, and curtailing use when it is scarcer. But it’s not clear exactly how to accomplish this. And people have trouble adjusting their use of electricity in response to market prices.

In the new study, researchers studied the effect of two pre-defined strategies for accomplishing flexibility: “flattening the curve” to equalize energy use throughout a 24-hour period, or shifting consumption to times of day when there has historically been lower power demand. Specifically, they looked at the timing of electric car charging, space heating in buildings, and hot water heating.

“Buildings are able to significantly change the load profile of electricity of the country of Norway,” says study team member Stian Backe, a researcher at SINTEF energy in Trondheim, Norway.

Backe and his collaborators used two computer models, one simulating Norway’s building stock and electricity use in buildings and the other simulating the European electricity market. Together these two models enabled them to determine how the two strategies would influence immediate power demand, as well as ramify through the European power system as a whole and investments in electricity infrastructure.

Both flattening consumption and shifting electricity use to off-peak times could reduce peak load on the grid by 10-12% in 2040, the researchers report in the journal Energy. All of this happens without the use of “dedicated flexibility assets, for example batteries,” Backe notes.

In turn, reducing peak load would make the grid more reliable and postpone the need for expensive investments in power infrastructure such as onshore wind installations, biomass plants, and nuclear power facilities.

Even bigger savings on infrastructure could come from improving the energy efficiency of Norwegian buildings, through more stringent efficiency standards for new buildings and accelerated renovation and retrofit of older ones.

Even if buildings get more efficient, energy demand in Norway is likely to continue to increase by 8-14% through 2040, because of an expansion in the building stock and greater adoption of electric cars. But more efficient space heating and an expected wide rollout of rooftop solar panels could reduce the amount of electricity delivered to buildings from the grid by 23-29% compared to 2020 levels.

Flattening consumption could help make best use of the expansion of rooftop solar generation, the researchers found. The other strategy, shifting electricity use to historically off-peak times, would result in a lot of the solar power going to waste.

Source: Backe S. et al. “Impact of activating energy demand flexibility in the building stock: A case study of Norway as a highly electrified country in the European power market.” Energy 2025.

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