During occasional stormy days this winter, wind power accounted for as much of Swedish energy production as nuclear power, around thirty percent.

"It is the cheapest power source today and Sweden is one of the countries in Europe that has the largest expansion at the moment," says Sandra Grauers Nilsson, head of Vattenfall's onshore wind power.

50 percent wind

The state energy authority has painted a number of scenarios on how the country's electricity generation might look around 2040 if it is exclusively operated with renewable sources.

In one of these, it is estimated that wind power at that point can account for about half of the energy required, about 90TWh.

According to Fredrik Lundström, research officer at the authority, it is fully possible to reach it within 20 years.

- Yes, that is very much the case, we have already built a lot, at the same time there are very many investments in progress in northern Sweden, he says.

Faster than expected

And the fact is that we have come halfway there soon. The industry expects wind power to account for one third of all electricity produced in Sweden in three years, not just for a few days - but on an annual basis.

"Yes, everything points to the fact that we are in that order around 2023," says Sandra Grauers Nilsson at Vattenfall.

Has it gone faster than you thought?

- Yes, it has. It's probably a lot faster than everyone expected.

See the science world "The Energy Revolution" on SVTplay or on Monday, April 6, SVT2 8 pm.