Leaked UK Grid Report Warns Net Zero Push Raises Blackout Risks

By City A.M - Jul 27, 2026, 11:00 AM CDT A confidential Cornwall Insight report commissioned by NESO says the growing share of decentralized renewable generation has reduced the grid operator's visibility over electricity supply and demand. A whistleblower alleges these forecasting shortcomings are increasing costs for consumers and could raise the risk of grid instability if left unresolved. Recent heatwaves have intensified scrutiny of Britain's electricity system after NESO issued emergency notices to secure additional generating capacity during periods of high demand. The UK’s net zero push risks leaving the country with higher electricity bills and more susceptible to blackouts, according to a leaked report commissioned by the national grid system.The report, produced by energy consultancy firm Cornwall Insight for the National Energy System Operator (Neso) and shared with The Times by a whistleblower, revealed that Neso cannot accurately map the modern power system amid the government’s green energy push.The whistleblower warned that Neso, which is owned by the government, was “flying blind, every minute of every day” in its ability to understand energy supply and demand.“We are risking a total blackout,” they said.The report found that inaccurate energy forecasts are inflating costs for consumers and leaving Neso less likely to be able to prevent blackouts.The source added that national grid engineers “have been raising these issues for two years” already but said executives “are too scared politically to say renewables are making the system unsafe.”In its report, the energy consultancy said the rise of renewable power sources such as wind farms, solar panels, and batteries has given grid operators “reduced visibility of the capacity which is supplying and taking power from the GB network”, complicating its ability to forecast supply and demand.‘Extreme temperatures’ hitting power suppliesThe report was completed just weeks before the UK’s June heatwave, and Neso has since warned that the “extreme temperatures” may hit power supplies as households’ fan and air conditioner use places a record strain on the grid.An overnight notice, issued by Neso on 9 July, called on energy companies to generate additional power supply to satisfy demand during the heatwave.This was the energy operator’s second warning in a month, with the group forced to call for more power during June’s heatwave, which saw temperatures hit a record high of 37.7CThis follows two of the UK’s leading energy industry bodies earlier this month calling on new prime minister Andy Burnham to slash green levies on energy bills for businesses or risk jeopardising economic growth.By City AMMore Top Reads From Oilprice.comOil Prices Plunge 5% After U.S. and Iran Halt AttacksSaudi Crude Tanker Goes Dark to Slip Through Bab el-MandebHormuz Tanker Crossings Sink to Lowest Level Since May as War Risk Spikes Download The Free Oilprice App Today Back to homepage