According to official figures gathered by the International Energy Agency, the global capacity for renewable energy generation has now exceeded coal for the first time. Renewables are now accounting for over 50pc of the world's growing power capacity.

Specifically, almost half a million solar PV panels were installed on a daily basis around the world last year. China is also worth looking at closely - its investment in wind power was so great that it set up the equivalent of two new wind turbines every single hour.

Green energy sources such as hydro, wind, solar, biomass and geothermal are being seen as a vital means of tackling climate change at an international level. At this stage, it is power generation capacity that is outstripping coal, and the next stage is for renewables to beat fossil fuels on actual generation of electricity.

Renewable power technologies are intermittent largely - with the exception of wave and tidal power - and they largely depend on the wind blowing or the sun shining. This compares to coal and other fossil fuels, which can be burned around the clock. As a result, green energy technologies will inevitably produce far less than their total capacity. Nonetheless, the achievement to date is a notable one and shows that work to progress a sustainable low-carbon global economy is starting to pay off.

Fatih Birol, the Executive Director of the IEA, said that the markets were seeing a transformation of the world's power markets, driven by green energy sources. The expansion of capacity also reflects the lowering costs of solar PV and onshore wind turbines - cost reductions which couldn't have been anticipated only five years ago. This decline in costs is expected to continue for some time.