Clean energy investment set a new record in 2015 and is now seeing twice as much global funding as fossil fuels. And rather than natural gas taking up the slack for the 15 GW of coal generation retired in 2015 in the US, 18 GW of the 26 GW of additional production capacity was wind and solar. This is likely to be a familiar scenario around the world as coal is phased out, and renewable costs are reduced.

As the figures show, we are approaching an age of rapidly changing global electricity production. Global wind energy production capacity has doubled every 4 years for the past 15 years (26% annual growth rate) and solar has doubled every two years (48% annual growth rate). Wind power usage is currently at 3.7% (at end 2015) of the worlds electricity, and this figure is likely to double by 2020 as trends continue. Many predict that although solar is starting from a low base, with the rapid increases in capacity seen and costs continuing to fall by up to a third by in the next four years, solar will eventually outpace wind to become the leading provider of electricity globally by 2050.

According to a recent report by the Abu Dhabi based IRENA group looking at the figures to 2025, costs for electricity produced by solar photovoltaics are set to fall by 59%, offshore wind by 35%, and onshore wind by 26%, compared to 2015. Electricity prices for concentrated solar power could also decrease as much as 43 per cent, depending on the technology used. By 2025, the global average cost of electricity from solar PV and onshore wind will be roughly 5 to 6 US cents per kilowatt hour.

Source: IRENA

Where challenges do arise however is in the relative complexity of integrating the various forms of distributed energy into grids that are currently designed for centralised power generation. Although storage prices are decreasing at a rate similar to other forms of clean technology, grid integration between countries may play a growing part in the need to decarbonise electricity production.

The most common way to meet electricity demand with supply for the gaps in production will probably continue to be load-following combined-cycle gas turbines, using natural gas. This is obviously preferable to coal, and overall the difference between renewable and slow-shifting coal and nuclear generation should not pose too much of a problem, as generic solutions are found to infrastructure issues.

As usual, fully realising the potential of renewable energy worldwide will depend on convincing policymakers and overcoming the vested interests of the fossil fuel lobby, as the climate changes for both industry and the planet as a whole.