{"id":62321,"title":"UK grid bottlenecks force costly curtailment of renewable energy output","publisher":"Stockmark.IT","author":"Stockmark.IT Website","published":"2026-10-26T09:12:27+00:00","modified":"2026-10-26T09:12:27+00:00","canonical_url":"https://stockmark.it/britains-renewable-energy-boom-is-hitting-a-grid-bottleneck/","markdown_url":"https://stockmark.it/britains-renewable-energy-boom-is-hitting-a-grid-bottleneck.md","json_url":"https://stockmark.it/britains-renewable-energy-boom-is-hitting-a-grid-bottleneck.json","category":"Financial","categories":["Financial","Renewable Energy"],"featured_image":"https://i0.wp.com/stockmark.it/wp-content/uploads/2026/10/uk-grid-bottlenecks-force-costly-curtailment-of-renewable.png?fit=1536%2C1024&quality=80&ssl=1","format":"news","language":"en-GB","content":"The United Kingdom is facing significant financial and operational challenges as its rapid expansion of renewable energy capacity outpaces the development of its transmission infrastructure. Despite heavy investment in green energy to reduce reliance on fossil fuels, the country continues to depend on natural gas for power generation due to inefficiencies within the grid. These structural limitations have resulted in substantial daily costs to balance the electricity network, with the grid operator frequently forced to take wind farms offline to manage oversupply in certain regions while simultaneously activating gas plants in areas experiencing shortages.\n\nOn 14 October, the grid operator incurred a cost of £47.9 million to switch off wind farms in areas with an excess of electricity. During the same period, it was necessary to power up gas plants in regions with low electricity supply. This pattern of operation reflects a broader issue where the physical network cannot efficiently transport power from generation sites to high-demand areas. The consultancy LCP Delta reported that wind farms and hydropower facilities with a combined capacity of 9 GW, sufficient to power approximately 8 million households, were paid not to produce power on that date. To compensate for the lost renewable output, the operator funded the operation of gas and biomass plants and purchased additional electricity imports from Europe via high-voltage subsea power cables.\n\nThe financial burden of these balancing activities has reached record levels. In September, the UK spent £505 million on balancing power on the grid, marking the highest monthly cost recorded to date. Projections indicate that these costs could reach up to £3.2 billion over the next year as the country works through a £150 billion programme of transmission infrastructure upgrades. These expenses are ultimately passed on to consumers through household energy bills. The disparity between the record pace of renewable energy deployment and the slower progress of grid modernisation has created a persistent bottleneck that hinders the transition to a low-carbon energy system.\n\nA specific point of congestion exists between Scotland and England, often referred to as the B6 boundary bottleneck. Currently, only two high-voltage cables move power between the two nations. This limitation has led to a long-standing practice of paying wind farms in Scotland to go offline, as the infrastructure cannot handle the surplus generation. Scotland produces roughly 19 per cent of the UK’s total electricity generation and contributes 37 per cent of its wind output, yet it uses only 8 per cent of the country’s electricity on average. Consequently, the surplus generation must travel south to meet demand in England and Wales. Costs associated with managing this specific bottleneck have averaged roughly £800,000 per day so far in the 2026-2027 period, which is approximately double the average for the 2025-2026 period.\n\nOperational challenges have also arisen during extreme weather events. In early October, the National Energy System Operator (Neso) requested emergency assistance from France, which responded by sending last-minute power supplies to the UK. Shivam Malhotra, head of power trading at LCP Delta, noted that the issue was not a lack of overall power supply but rather the inability to transport power to where it was needed. Additionally, during the summer months, a high-pressure heat dome reduced renewable energy output while demand for air conditioning and refrigeration soared. This led Neso to bring in independent investigators to examine whistleblower claims regarding a near-blackout incident during record-high temperatures in late June.\n\nThe demand for new grid connections has surged in line with the accelerated deployment of renewable energy. The UK energy regulator Ofgem reported that demand for new grid connections increased from 41 GW to 125 GW between November 2024 and June 2025. This surge has left several green energy projects stranded in the connection queue. In response, National Grid submitted an additional package of proposals to Ofgem on 15 October under the RIIO-T3 load re-opener process. The package includes 19 projects across England and Wales, representing about £4.5 billion of proposed investment. This forms part of National Grid’s broader plan to invest approximately £31 billion on the grid in England and Wales between 2026 and 2031, aiming to increase network capacity and accommodate increasing levels of clean power generation."}