(Bloomberg) -- In the middle of an energy crisis, with European power and gas prices spiking to unprecedented heights, Nordic homes and factories can plug in this weekend for almost free.

Average Saturday power prices in the northern corner of Europe slumped to 4.17 euros a megawatt-hour on the Nord Pool ASA exchange in Oslo, the lowest since November 2020. Some local prices were even lower. By comparison, they were at 333 euros in France and 148 euros in Germany, Europe’s biggest market.

The 80% drop in prices from Friday’s level is due to a mix of lower demand as the region takes summer vacations earlier than the rest of the continent, gusty weather and plenty of water filling up the reservoirs in Norway and Sweden. The plunge may just be temporary, but it shows the impact that a vast buildout of renewable energy is having on prices and volatility.

“This is what happens when we have several bearish factors combining at the same time,” said Pontus Lohman, an analyst at Skelleftea Kraft AB in Sweden. 

Sweden’s energy minister Khashayar Farmanbar said this week in an interview that the energy markets should get ready for more volatility. The nation is building out wind power capacity and output can vary widely depending on how much it blows. While not immune to what’s going on elsewhere in the European gas market, the Nordic market isn’t closely tied since stations burning the fuel are sparse in the region. Worries over gas supplies this winter have sent power futures to records across the continent. The next-year benchmark contract in Germany surged to a record 371 euros Thursday. The equivalent contract on the Nordic market traded at about 110 euros.

©2022 Bloomberg L.P.