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Renewables are "growing strongly" and will continue to do so, according to Fatih Birol, executive director of the International Energy Agency.

"We just told the entire world last week that the renewable electricity capacity now took over coal and became the number one source of electricity capacity in the world," Birol told CNBC at The New York Times Energy for Tomorrow Conference in Paris Thursday. He went on to state that renewables were becoming cheaper and "much more cost effective." Government support – especially from the U.S. and China – was still needed, Birol went on to explain, adding that "in the absence of government support renewables … May face some difficulties."





Capacity overtaking coal?

Last week, the IEA said renewable energy had moved past coal in 2015 to become the biggest source of global electricity capacity. The U.S. Energy Information Administration describes capacity as being "the maximum electric output an electricity generator can produce under specific conditions."

2015 "marked a turning point for renewables" the Paris-based body said, with clean sources of energy representing over 50 percent of the planet's new power capacity, hitting 153 gigawatts, a 15 percent increase in electricity capacity on the year before. The IEA said that in 2015 around 500,000 solar panels were installed every day, while in China – which was responsible for 40 percent of all increases in renewable capacity – two wind turbines were installed every hour. In its latest renewables forecast, the IEA said that the next five years would see this growth continue, with 30,000 solar panels and 2.5 wind turbines installed per hour. Renewables would see their share of electricity generation grow from 23 percent in 2015 to 28 percent in 2021, it stated.

Still oversupply in oil