National Grid DSO cuts curtailment by 20%, avoiding 450GWh in six months

National Grid DSO says smarter outage planning spared 450GWh of curtailed generation between April and September 2025.

The distribution system operator, which serves more than eight million customers across the UK, says the avoided curtailment represents a 20% reduction against the total curtailment required for maintenance and upgrades over the previous 12 months. It also surpasses its April 2025 target to cut annual curtailment during planned outages by 300GWh.

Curtailment, which involves asking local generators to turn down output so engineers can work safely during maintenance and upgrades, remains a critical tool for operations. However, it also means that power has to be imported from further afield to ensure homes and businesses remain powered on during the work. 

According to National Grid DSO, by sharpening its outage modelling to target curtailment only where and when it is needed, it was able to keep more local, low-carbon generation online for longer, supporting affordability and decarbonisation for National Grid Electricity Distribution customers.

Helen Sawdon, Head of Operations at National Grid DSO, noted, “Beating our target is great news for local energy generators across our region, and points towards continued opportunities for growth.

“Keeping our energy system safe and reliable naturally requires us to take some of our network equipment out of service temporarily while we undertake maintenance and upgrades.

“By focusing on how we model network outages, we can precisely target the curtailment to exactly where and when it’s needed. This keeps power flowing for longer – particularly from local low carbon providers who are helping to deliver more affordable power through our flexibility market, lowering both customer bills and carbon emissions at the same time.

“The less we curtail our customers, the more attractive it is for energy producers to connect into the system. This increases market competition that lowers energy costs and moves us towards our vision of abundant locally generated, clean and affordable energy powering the communities and businesses we serve.”