Finnish renewables operators anticipate electric boiler boom

The high number of hours with negative electricity prices in Finland has sparked a boom in electric boilers, whose combined capacity is expected to triple within three years, rising from around 500 MW to more than 1.5 GW. The international news outlet Montel reported.

Finland has seen rapid growth in renewable energy sources in recent years. Installed wind power capacity has tripled since 2020 to almost 7 GW, while solar power capacity has risen from 0.2 GW to more than 1 GW.

One consequence of this development is the high number of hours with very low or even negative electricity prices. Last year, Finnish electricity producers had to pay to feed power into the grid for 467 hours.

Finnish heat suppliers want to take advantage of low electricity prices and, according to Montel, plan to bring around 1,000 MW of new electric boilers online by 2026.

"Switching from biomass or fossil fuels to electricity during periods of low electricity prices can save large energy companies millions," said Riku Merikoski, a senior analyst at Axpo.

The cannibalisation effect on renewables

Electricity producers in Finland welcome heating companies’ plans to install flexible electricity consumers and hope they will help mitigate the impact of the cannibalisation effect on electricity prices for renewable energy sources.

This occurs during hours when high renewable power generation exceeds demand, causing electricity prices to fall to negative levels.

According to Merikoski, the planned installation of around 1,000 MW of electric boilers could help, but current plans for further investment in wind and solar power plants will effectively cancel out this positive effect.

"Far more would be needed to reverse the trend of rising numbers of hours with negative electricity prices," Merikoski added.

Electric boilers in the Czech Republic

Large electric boilers have also been used in the Czech Republic for many years to generate heat when spot market electricity prices are low or to provide balancing services. The first 12 MW hot-water electric boiler was installed at the Příbram heating plant in 2014.

According to data from the Czech transmission system operator ČEPS, a.s., 12 were in operation at the end of November last year, with a combined capacity approaching 200 MW. Further projects are also in preparation.

The largest electric boiler currently operating in the Czech Republic is at the Poříčí power plant, part of the ČEZ Group. It was commissioned at the end of 2020 and has a capacity of 30 MW.