Can the Swedish electricity grid be affected by a blackout?

When the power was extinguished in Spain, Portugal and parts of France, Sweden had to move in. The entire Swedish electricity grid is interconnected, but also down to the continent.

– We could support the system slightly through a connection to Denmark. We sent some extra power, says Erik Ek at Svenska Kraftnät.

Last time Sweden Had a major power outage was in September 2003. A total of around five million inhabitants in Sweden and Denmark was then hit. In the same way that Portugal is strongly linked to the Spanish network, Sweden is linked to Denmark.

– It is naive to think that it would not happen in other countries and it has already happened once in Sweden. We have had big disorders here as well, says Erik Ek

On September 23, 2003, he sat himself and worked in the control room when it turned black. It can be described as that there were several errors on each other in the electricity grid.

– An electrical system is always dimensioned in such a way that it should make certain errors and then you should have reserves to replace it and then the system is robust again for the next thing. But if it happens too many things than the system is dimensioned because then it can turn black, says Erik Ek.

The lesson from 2003 became that a type of stations that could increase stability was built.

– So there are several things that you often see that you can improve. But then it is a technical system, you can never make sure that such things never happen, says Erik Ek.

Filip Johnsson, professor of energy systems at Chalmers University of Technology, believes that the Swedish electricity grid is more robust than the Spanish.

– We have a heavy industry and a high electricity consumption per capita. Then we have a lot of buried cables, large backbone networks and we have to keep in mind that we do not actually use the electricity grid fully, he says.

However, he sees new potential risks for major power outages in the future.

– Firstly, we have the geopolitical dimension with risks for cyberattacks. On the one hand, we have climate change that can cause more extreme people with storms and floods.

Does it matter what type of energy is used in the network?

– Yes, but of course it does. We have got more wind and sun, which means that there will be more variations in electricity generation. But we have also developed techniques that handle it. At the same time, it can be stated that in Spain all their nuclear power plants were automatically closed.

The reason for this is, according to Filip Johnsson, that it is not possible to eject too large amounts of power from a point when the rest of the net is down.

– If it becomes a break, you must also start up gas turbines to maintain various functions on the nuclear power plants including ensuring cooling. You can’t just cut the wires. So the belief that nuclear power is very robust and can always deliver is not quite right here, says Filip Johnson.