Solar and wind power can grow enough to limit global warming to 1.5C if the 10-year average compound growth rate of 20% can be maintained to 2030, independent climate think tank Ember said in a report on Wednesday.

Solar generation rose 23% globally in 2021, while wind supply gained 14% over the same period. Together, both renewable sources accounted for 10.3% of total global electricity generation, up 1% from 2020, data from Ember showed.

The Netherlands, Australia and Vietnam had the fastest growth rates for the renewable sources, switching around 10% of their electricity demand from fossil fuels to wind and solar in the last two years, they said.

"If these trends can be replicated globally, and sustained, the power sector would be on track for 1.5 degree goal," Ember said in their report.

The main issue currently slowing the growth rate is on-the-ground constraints like permitting, and if governments want to supercharge growth they need to solve problems slowing deployment, Ember's global lead Dave Jones said.

However, despite gains in wind and solar, coal-fired power generation saw its fastest growth since at least 1985, up 9% in 2021 at 10,042 terawatt hours (TWh), or 59% of the total demand rise, the report said.

This came in a year of rapid demand recovery, as 2021 saw the largest recorded annual increase of 1,414 TWh in global electricity demand in 2021, up 5.4% and the equivalent of adding a new India to global demand, they said.

"We're getting closer to that break-even where wind and solar can cover new electricity demand, but we are still not quite there. If we maintain those growth rates we see, we will be there shortly," Jones said.

The biggest demand rise was recorded in China, up 13% in 2021 compared to pre-pandemic levels in 2019, the data showed.

The country relies largely on coal for power production, but passed the one-tenth of power generation from wind and solar landmark for the first time in 2021 along with six other countries, the report said.

China "is installing not only record levels of wind and solar, but also installing record levels of clean electricity like hydro, nuclear and bioenergy which means their coal generation will start falling," Jones said.

"What's not clear is how quickly that will be," he added.

China plans to continue to use coal as a vital part of its energy strategy, as it bids to balance economic stability with its longer-term climate goals.