UK watchdog warns slow grid upgrades could push up energy bills
Britain's National Audit Office says delays in a £70bn electricity grid modernisation programme could push extra consumer costs to £7.8bn a year by 2030. Only 16 of 80 required projects are finished so far.
The UK's National Audit Office (NAO) has warned that consumers face higher energy bills unless the government accelerates a massive programme to upgrade the electricity grid needed for the shift to renewable energy.
According to the NAO, if upgrades are not sped up, the extra costs of managing the country's ageing power network — costs that are ultimately passed on to consumers — could reach £7.8bn a year by 2030.
Progress lags behind
A £70bn programme is currently under way to modernise Great Britain's pylons, overhead lines and substations, allowing more electricity from wind and solar farms to reach homes. Of the 80 projects needed to meet the government's target of decarbonising the grid by 2030, only 16 have been completed, with most still in early stages.
NAO head Gareth Davies said the scale and pace of the planned work would test systems never designed for such demands, warning that failing to deliver the upgrades would hold back economic growth and raise bills.
Constraint costs already climbing
When the grid cannot carry enough power from where it's produced to where it's needed, the system operator pays wind farms to switch off and gas plants elsewhere to switch on to meet demand. These so-called constraint costs, which are added to bills, totalled £1.9bn in 2025-26 and could rise to £7.8bn by 2030 without faster action.
Meanwhile, transmission owners — the private companies that build and manage the network — will need to more than quadruple annual spending on upgrades, from £2.5bn in 2025-26 to over £11bn by 2027-28.
Regulator Ofgem estimates households could save about £30 a year if upgrades proceed at the required pace, thanks to reduced constraint costs, though the NAO called meeting that timeline very challenging. Some projects are already expected to run past 2030, meaning new generation capacity may connect to the grid before the necessary upgrades are finished.
The NAO also said neither Ofgem, system operator Neso, nor the government publish enough data on project costs and progress, calling for greater transparency. Geoffrey Clifton-Brown, who chairs parliament's Public Accounts Committee, said the grid must be able to handle rising demand from new homes and data centres, and that responsible bodies must deliver projects on time with transparent reporting.
Ofgem said it welcomed the recommendations, while energy minister Michael Shanks said the report underscored the cost of years of underinvestment and that government reforms were now building the infrastructure needed.
