Britain has increased its electricity exports to France due to high winds.

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Britain increased its electricity exports to France on Friday as high winds across the country left it with power oversupply.

France has offset up to 4 gigawatts of power from its nuclear fleet – enough to power millions of homes – by importing more electricity from Britain, Montel Analytics reports.

Intermittent wind and solar power is used to provide electricity to homes, businesses and factories, reflecting the dynamic nature of the power system.

Gale-force winds of up to 114mph highlight Britain’s dependence on its neighbors to buy and sell electricity to balance its increasingly weather-dependent power system.

Electricity supply and demand must be balanced by the second, meaning that during periods of high wind, Britain and other countries may be producing more than they can use themselves.

Britain has a number of cables connecting its power system to neighboring countries including France, Norway, the Netherlands and Belgium.

Jean-Paul Harman, director of Montel Analytics, said France had started exporting electricity to other countries early on Friday due to its own low domestic demand.

But soon traders began to import electricity from Britain as it began to become scarce. “France was exporting to all its borders,” he said.

“Then there’s Britain, we don’t want your power, we want to reverse your relationship. So France was already exporting and then got more energy from Britain.

“They[France]rejected some nuclear power plants because they didn’t have more capacity to export.”

Britain now has around 30 gigawatts of wind capacity, half of which is offshore, where wind speeds are very high.

If the production from wind and other generators is too high and more energy cannot be exported, the country’s national energy system operator must pay the wind power plants to curb their production.

When the storm hit, many wind farms in Britain had to pay to turn off even their exports, according to Montel Analytics.

France’s nuclear power fleet is the state-owned giant EDF.

Nuclear power plants, which provide most of France’s electricity, cannot be turned on and off as easily as gas or coal power plants, but the output can be adjusted up to a point.

As well as adjusting its nuclear production, France uses overnight electricity to deliver water to hydroelectric reservoirs, meaning it is ready to send the water to generate electricity when needed.

Britain’s electricity system is becoming increasingly complex to manage as it becomes increasingly reliant on electricity from wind and solar power.