Decarbonising Will making 2030 the goal cost more than 2035? Come clean, Labour

The government's plan to decarbonise the electricity system by 2030 is a vast undertaking.

- Nils Pratley

Energy companies will throw £40bn-plus annually at the effort, backed by financing that ultimately affects consumers' bills. So it is extraordinary that no official body seems able to answer this question: will it cost more to complete the job by 2030 rather than by the old 2035 timetable? Is it more expensive to go faster?

That is not to dispute the necessity of generating electricity from clean domestic sources, an ambition shared widely across the political spectrum for reasons of security of supply and climate emergency. But the pace of decarbonisation can also affect the cost for consumers, a point Ed Miliband, the energy secretary, tends to skip over too breezily when he argues that security, sustainability and affordability are now perfectly aligned.

The report by the state-owned National Energy System Operator (Neso) earlier this month supported Miliband's argument that clean power by 2030 is "achievable", albeit with the heavy qualification that the task is "immensely challenging". But Neso's analysis did not compare the costs of 2030 against a 2035 timetable. Instead, it assessed 2030 against a "counterfactual" that imagined no meaningful acceleration.