The fall was driven by a flood of shale natural gas supply and renewable power increasingly displacing coal, the International Energy Agency (IEA) said.
Thousands of people gathered in the Romanian capital Bucharest and other cities on Sunday in a show of opposition against the Rosia Montana project in Transylvania
It is the third such attack on Cerrejon infrastructure — a joint venture between Anglo American, BHP Billiton and Xstrata — this year and follows seven incidents in 2012.