The Global Trends in Renewable Energy Investment 2014 report,  says solar in particular improved its cost-competitiveness, with 39GW installed globally last year, up from 31GW in 2012.

The report points out the $35.1bn investment drop was partly down to the falling cost of solar systems. The global average levelised cost of electricity from crystalline silicon PV systems declined by 53% in 2013, it says.

The