The world faces more years of high energy prices and emissions unless the electricity sector changes faster after demand hit a record last year, the International Energy Agency said Friday.

The economic recovery from the Covid pandemic, combined with unusual weather conditions, caused electricity demand to jump by more than six percent in 2021, the largest increase since 2010, the IEA said.

In absolute terms, the increase of more than 1,500 terawatt-hours was the largest ever, the Paris-based agency said in its semi-annual Electricity Market Report.

This pushed prices to unprecedented levels while emissions from the electricity sector rose by seven percent in 2021 -- an all-time high after having decreased the previous two years, the IEA said.

While renewable power experienced "impressive growth", electricity generation from coal and natural gas hit record levels, the report found.

"In the absence of faster structural change in the sector, rising demand over the next three years could result in additional market volatility and continued high emissions," the IEA said.

IEA executive director Fatih Birol said emissions from electricity must fall by 55 percent by 2030 if the world is to meet a target of net-zero carbon emissions by 2050.

"But in the absence of major policy action from governments, those emissions are set to remain around the same level for the next three years,” Birol said in a statement.

"Not only does this highlight how far off track we currently are from a pathway to net zero emissions by 2050, but it also underscores the massive changes needed for the electricity sector to fulfil its critical role in decarbonising the broader energy system."

Birol also warned that high electricity prices "have been causing hardship for many households and businesses around the world and risk becoming a driver of social and political tensions."

China accounted for around half of the global growth in electricity demand last year. The country experienced power cuts due to coal shortages -- a problem also encountered by India.