Due to the same "green" politicos having been in power the last 8 years [1]. The power plants they closed could have been kept in service - they had been recertified up to 2035 - but they closed them anyway. This was a political decision, not one based on demand - support for nuclear power has surged in Sweden - or technological deficiencies.

[1] https://08nytt.se/naringsliv/mp-erkanner-avvecklat-karnkraft...