UK grid operator streamlines grid connection process for renewables up to 5 MW

Regulator Ofgem approves higher threshold for a transmission system impact assessment requirement applying to distributed generation projects in England and Wales. The move is expected to lower development costs for projects with capacity between 1 MW and 5 MW.

More than 300 UK distributed generation projects can expect to benefit from a streamlined grid connection process, according to Great Britain’s electricity system operator, following a change to the thresholds for assessing impacts on the transmission system. It is the latest development in an ongoing connections reform process expected to fast-track 65 GW of solar projects.

Industry regulator Ofgem has approved a modification to the Connection and Use of System Code (CUSC) that raises the capacity threshold which determines when a Transmission Impact Assessment (TIA) is required. The threshold has been raised from 1 MW to 5 MW. The National Energy System Operator (NESO), which proposed the change, claims it will enable faster connections for small-scale energy projects such as community energy projects.

Previously, solar and other generating projects with capacity of 1 MW or higher required a transmission impact assessment (TIA) before they could be connected to the grid. This not only extended the time taken to secure a grid connection but also exposed project developers to greater risk if significant transmission works were required.

NESO said the change directly impacts 337 projects currently in the connections queue with combined capacity totaling 682 MW. The system operator for Great Britain said it has worked closely with distributed network operators to evaluate the impact of raising the TIA threshold and its analysis confirms the change will “significantly improve” the connection process for smaller distributed generation projects.

In a statement, NESO Director of Connections Reform Matt Vickers said the change is an “important step” in supporting future community energy and smaller scaler projects.

“By raising this threshold, we can unlock the connections process for over 682MW of smaller projects without sacrificing on resilience of our electricity networks,” he said.

While the new threshold only applies to projects in England and Wales, NESO said its broader package of connection reforms will benefit projects across Great Britain. In Scotland, a TIA is required for projects above 200 kW on the mainland while the threshold for projects on the Scottish islands is set at 50 kW. Ofgem has said it expects to continue reviewing the threshold in Scotland to deliver “similar benefits there, if technically feasible.”