SSEN Transmission, working in collaboration with SSEN Distribution, have taken an important step in their work to connect renewable generation projects to their network in the north of Scotland more quickly, by increasing the threshold at which new projects will require a Transmission Impact Assessment (TIA) for large areas across the region.

A four-fold increase in the threshold – from 50kW to 200kW – will see more projects being able to connect without the cost and delay that comes with this assessment needing to be carried out.

The change means that around 35 customers in mainland Scotland, with a combined generating potential of over 5MW, will now be able to connect significantly earlier than previously anticipated. The threshold adjustment allows some prospective customers to save on the cost of application fees, too.

The change comes into effect for SSEN Transmission's mainland operating area in the north of Scotland but does not include grid supply points on the islands surrounding the mainland, where the threshold remains 50kW due to transmission network constraints.


This update comes after a thorough review that considered a range of factors, including the likely number of customers, risk assessment of the security of the transmission network, and a study of the contribution new technologies can make.

Speaking on the announcement of the TIA threshold increase, Josh King, the Managing Director, Gensource, and Chair of Solar Energy Scotland, said: "We welcome the recent decision to reduce barriers to renewable energy generation and storage. This significant development follows ongoing dialogue between SSEN and Solar Energy Scotland (SES).

"The increase in the upper limit for renewable connections from 50kW to 200kW brings SSE's limits in line with the rest of mainland Scotland. This move will be particularly beneficial for businesses in the North of Scotland, supporting them to decarbonise their operations and generate clean, affordable energy.

"We also welcome SSE's commitment to keeping this limit under continuous review and look forward to ongoing collaboration between SSE and SES to remove barriers faced by industry. Such progress is essential to achieving the Scottish Government's proposed ambition of installing 4-6GW of solar capacity by 2030."

An example of the impact the TIA threshold change will have comes in the form of a 130kW industrial customer connection project in Dundee. Under the previous threshold of 50kW, the scheme was given a proposed 2031 connection date, with extensive work needed to be carried out. Now, the project can connect to the transmission network as soon as it is ready, allowing more clean power to flow through the grid.

SSEN Transmission will continue to review the TIA threshold and assess any future opportunities to further increase it or identify any emerging concerns around network security that might require it to be adjusted.