Shops in Finland may have to take turns closing for a few hours this winter to reduce their energy use.

Fingrid, Finland's majority state-owned electricity transmission grid operator, and lobby group Finnish Energy told Yle that power cuts lasting a few hours could be possible when the weather cools.

As winter approaches, stores in Finland are planning ahead for the possibility of electricity shortages. Setting up a power schedule is especially important in rural areas to make sure all shops aren't closed at the same time.

While planned, power cuts still pose challenges for stores. Freezers can be turned off for a few hours, but checkouts require a constant stream of electricity to function.

It's now up to Finland's some 2,800 food stores to agree who will close and who will stay open if power is rationed in a particular area.

"We're not totally finished yet, but we're moderately prepared already," said Lauri Kulonen, emergency preparedness manager at Finnish Grocery Trade Association PTY.

Europe's electricity and gas market has come under stress since Russia's invasion of Ukraine.

In Finland, electricity supply could become tight as full electricity generation of the Olkiluoto 3 reactor (OL3) will not start until December, three months behind schedule. The reactor was, however, originally scheduled to be completed in 2009, but it has faced a seemingly endless series of technical problems, delays, cost overruns and legal disputes.

Finland meanwhile plans to target households with an energy saving campaign in August. Similar campaigns are already underway in many EU countries including Germany, Italy and France.