According to the latest report by the International Energy Agency (IEA), in 2015 the total growth in annual renewable electricity capacity, at 153 gigawatts (GW) was greater than ever before. This total included record increases in both onshore wind (63 GW) and solar photovoltaics (49 GW) as price reductions make turbines and solar panels increasingly competitive. Furthermore, “For the first time, renewables accounted for more than half of net annual additions to power capacity and overtook coal in terms of cumulative installed capacity in the world.”

But while this sort of snap-shot is valuable, it is, perhaps, more interesting to focus on the trend line for the future predicted by the IEA, the world’s leading energy institution.  For the bulk of the report is taken up with their forecasts for the next five years.

Interestingly, the projected figure for the growth in global renewable electricity capacity has increased from last year’s figure by a significant 13 per cent. The figure for growth by 2021 is now estimated to be 825 GW. Much of the increase is attributed to policy changes in China and the US, where the extension of federal tax incentives for the medium term should prove beneficial for renewables even at current low prices for gas.(Subject to the caveat that the report was finalised before the results of the US election were known.)

China accounts for some 40 per cent of all the growth in the forecast. The IEA estimates that by 2021 more than one-third of global cumulative solar PV and on-shore wind capacity will be located in China, where pollution and policy change have both been dramatic. Only a few years ago, who would have thought that we would see the Chinese warning a post-election US not to renege on its commitments under the Paris Agreement on Climate Change.

Overall, the IEA expect that in the next five years the share of overall world electricity generation attributable to renewables will rise from 23 per cent today to nearly 28 per cent in 2021. This reflects their striking prediction that over that period renewables growth will constitute more than 60 per cent of all the growth in electricity generating capacity. The report notes that there are major differences between the various regions of the world. In mature markets like the US and the European Union, the rate of increase of electricity demand will be less than the rate of growth of renewable generation, but in emerging markets, demand for electricity will still be growing faster than the rate of increase of renewable generation.

The picture is more mixed in the two other main sectors:-  transport and heat. With the use of biofuels predicted to grow only slowly, as low prices make oil and gas more competitive, 2021 should see biofuels constituting a modest 4 per cent share of transport fuel demand. Similarly, in the heat market, which accounts for over half of the world’s final energy consumption, renewable heat (other than traditional biomass) meets nearly 9 per cent of demand. This figure should rise to over 10 per cent by 2021.