Are heat pumps ineffective in extreme cold?

The Nordics debunk the clichés

“During my research on the subject, I read that a heat pump could produce a quantity of heat equivalent to three to four times the quantity of electricity injected,” explains the fifty-year-old, communications advisor in a company. railway.

“That alone lit a light bulb in my brain. I told myself that this must be a smart solution,” he says.

Hundreds of thousands of Norwegians, including Crown Prince Haakon, had this enlightenment.

Along with Finland and Sweden, Norway is among the countries best equipped with heat pumps, elevated to the same level of solution to climate change as electric cars by the International Energy Agency, since heating today generates today some 4 billion tonnes of CO2, around 8% of global emissions.

The fact that Nordic nations with very harsh winters are at the forefront debunks the preconceived idea that this technology would not work in extreme cold.

An idea that fueled resistance on the continent.

“False myths”

“There are many erroneous myths about heat pumps: certain oil and gas producing countries such as Russia, certain people, certain sectors and certain companies do not want this transition,” deciphers researcher Caroline Haglund Stignor of the institutes Swedish research institute RISE.

“Yes, heat pumps work in cold climates. Yes, they work in old buildings,” she summarizes.

Absent on the rudimentary first generation models, defrosting systems and variable speed compressors now allow these devices, which take calories from the outside to reinject them inside, to be effective in a wide range of applications. temperatures.

Even if their effectiveness declines when it is cold, the equation remains positive, experts say.

“It’s a mature technology that works and warms millions of homes every winter, but which is constantly being developed to be even better,” emphasizes Caroline Haglund Stignor.

According to a study by the independent group Regulatory Assistance Project (RAP), aerothermal heat pumps (using heat in the air) specially adapted for cold climates can be up to twice as efficient as electric heating with temperatures outdoor temperatures of -30°C.

In France, detractors of the heat pump claim that it generates excess electricity consumption and is not suitable for “thermal sieve” housing. Not to mention the installation cost.

The attachment to oil or gas boilers is tenacious. In Germany, the coalition partners were torn apart this year over the timetable for banning fossil heating: it will ultimately be 2045. But the State subsidizes heat pumps, which in 2022 would only equip 3% of homes, and the installations are finally starting to take off.

Source of savings

Unlike many European countries, Norway has almost no urban heating and has banned oil boilers since January 2020. To spend its winters warm, it relies mainly on its electricity, which is abundant and clean because it is almost entirely sourced. hydraulic.

By producing approximately 3 to 5 kWh of thermal energy for each kWh of electricity consumed, heat pumps are a vector of energy efficiency, a major axis in the fight against climate change, but also a source of savings.

After swapping his electric radiator for his air-to-air heat pump two years ago, Øyvind Solstad saw his electric bills decrease.

“The first four months, our consumption fell by 20% compared to the year before, while we also bought an electric car in the meantime,” he says.

Even if the initial investment is substantial (around 2.500 euros with installation), he thinks he can recoup it “in just a few years”.

Bonus: in summer, its heat pump also serves as an air conditioner.

When electricity prices hit the ceiling last year in the midst of the energy crisis linked to the war in Ukraine, sales of heat pumps reached record levels in Norway with a jump of 25%.

They continued their momentum in the first half of this year.

“Norwegians have internalized the fact that we should expect higher electricity prices in the coming years than in the past,” notes Rolf Iver Mytting Hagemoen, president of the Norwegian Heat Pump Association ( NOVAP).

“And energy efficiency is an issue that is ever more relevant.”

Illustrative image of the article via Depositphotos.com.