Chapter 8 of Part 2 of the Energy Act 2013 (c 32)(“the Act”) imposes a duty “the emissions limit duty” on operators of fossil fuel plant granted planning consent on or after 18th February 2014, to ensure that its annual emissions of carbon dioxide attributable to fossil fuels do not exceed an amount (“the emissions limit”) determined according to a formula set out in section 57(2) of the Act.