Networks launch scheme to unlock spare capacity in southern England

A new scheme to make greater use of network capacity in southern England has been launched by National Grid Electricity System Operator (ESO), National Grid Electricity Transmission and Scottish and Southern Electricity Networks (SSEN).

An active network management (ANM) system is being introduced in the region that will allow distributed generators with flexible connection agreements to continue providing power during periods when they previously may have been required to switch off in anticipation of a fault or to avoid overloading the network.

They will instead be able to adjust their output in real time to stay within the necessary limits.

“It either means that those existing generators get greater access without network investment or it allows you to connect more generators to fill that network capability,” said ESO head of networks Julian Leslie.

He said connecting customers will be provided with data indicating to what extent they are likely to be required to curtail their output, which they can then run through their businesses models and make a decision on whether to accept a flexible connection.

Leslie told Utility Week the scheme is “unique” in that “it’s one of the first that transitions between distribution and transmission, so it’s truly a whole-system solution”.

Stewart Reid, head of future networks at SSEN, said: “It is great to see ANM being applied at scale in the south of England.

“The concept of ANM-enabled ‘smart-grids’ originated in Orkney, about as far as you can get from these latest installations, and shows how the combination of renewables and smart network management techniques can help the UK meet its net zero goals.”

The ESO said ANM systems offer “vast improvements” over the traditional intertrip systems used to switch off generators during adverse network conditions.

The system is expected to go live in the first quarter of 2021.