According to a report by the International Energy Agency (IEA), 700GW of renewable energy will be added to the world’s total installed capacity over the next five years.
This would mean that clean would make up 26% of total output by 2020, a rise of four percentage points on the current total.
The agency, which is based in Paris, says: "By 2020, the amount of global electricity generation coming from renewable energy will be higher than today’s combined electricity demand of China, India and Brazil."
The IEA calls the move "a remarkable shift in a very limited period of time".
In July, a leaked consultation paper said if European countries are to keep their climate pledges then half of the continent’s electricity would have to come from renewable sources by 2030.
The US state of Hawaii is to run entirely on renewable energy by 2045.
In the second quarter of 2015, the UK generated a record 25% of its electricity from renewable sources.
Image: A wind farm in Xinjiang, China (Chris Lim/Wikimedia Commons)