The TIA process is costly, delaying or effectively blocking local power projects over 1MW in size. Image: Keith Edkins via Wikimedia Commons.

The UK’s National Energy System Operator (NESO) has issued a proposal that would see the transmission impact assessment (TIA) threshold rise from 1MW to 5MW.

The proposal has been raised as an urgent modification in the hopes that the change, CMP446: Increasing the lower threshold in England and Wales for Evaluation of TIA, can be made before the grid connection reforms promised for this year.

If approved, it could also help to ease the new connections process, which proposes that projects under the lower limit evaluation of TIA thresholds do not have to go through the Gate 2 process.

National Grid Electricity Transmission (the transmission owner for England and Wales) initially suggested the modification, Shraiya Thapa of law firm Freeths told our sister site Current± in a recent interview. To read more about ongoing grid connection reforms, visit Current±.

According to NESO, “implementation of this modification before the Gate 2 window opens will release around 400 distributed generation projects from having to demonstrate Gate 2 compliance or alignment with Clean Power 2030 targets.”

The current TIA process has been criticised for being costly, delaying or effectively blocking local power projects over 1MW in size. Solar industry trade association Solar Energy UK issued a “warm welcome” to the news that “a burdensome element of red tape that has added many years to getting projects off the ground”.

The move has come earlier than expected, SEUK said, and it will contribute to the “solar rooftop revolution” energy secretary Ed Miliband has promised. The modification will only enact change in England and Wales, but “a comparable but less radical” change has already been implemented in Scotland.

Last summer, Scottish and Southern Electricity Networks (SSEN) raised the threshold for TIAs from only 50 kilowatts – about twelve times the size of a typical domestic installation – to a more substantial 200kW. Doing so significantly expedited 35 projects in central and northern Scotland, their capacity coming to 5.2MW.

Chris Hewett, chief executive of SEUK, said: “Reducing barriers for renewable energy is always a welcome move, so we are delighted to see NESO’s announcement today, which has come somewhat earlier than we had anticipated. Slashing the red tape for larger-scale rooftop projects, and potentially for small-scale groundmount systems, will be a real economic boon.”

The announcement should greatly accelerate the deployment of photovoltaics on warehouses in particular. Two years ago, the UK Warehousing Association, working in conjunction with Solar Energy UK, estimated that the sector could install 15GW if grid challenges were resolved.