Ministers have been urged to “open their eyes” to the need to build a vast network of new electricity grids to allow countries to hit climate goals, the chief of the world’s energy watchdog has said.

Fatih Birol, the executive director of the International Energy Agency (IEA), has warned that the equivalent of the entire global electricity grid – 80m km of grid – needs to be added or refurbished by 2040 to hit climate targets and ensure reliable power supplies.

Global investment in energy grids needs to double to more than $600bn (£492bn) a year by 2030 to hit national climate targets after “over a decade of stagnation at the global level”, the IEA said.