IN Brief:
- SP Energy Networks has started a five-year, £12 billion overhaul of the transmission network across central and southern Scotland.
- The programme includes 12 new major substations, circuit upgrades, overhead line reconductoring, and underground cable replacement.
- The work forms part of the RIIO-T3 period and is intended to increase transfer capacity, reduce constraints, and prepare the network for higher electrification.
SP Energy Networks has started a major transmission investment programme across central and southern Scotland, setting out a five-year schedule of network reinforcement running from 2026 to 2031. The company has put the value of the programme at £12 billion, with works centred on new substations, uprated circuits, reconductored overhead lines, and sections of underground cable replacement.
The first phase of the programme includes 12 new major substations, 450 km of existing circuit upgrades, 87 km of overhead line reconductoring, and 35 km of underground cable replacement. Taken together with other planned reinforcement, the wider programme covers more than 570 km of lines either upgraded or replaced. The works are intended to increase network capacity, reduce constraints, and move larger volumes of electricity from renewable generation into homes, businesses, and industrial demand centres.
The investment is also expected to feed directly into the transmission supply chain. SP Energy Networks has said the programme will create around 1,400 direct jobs and support more than 11,000 more across the wider supply chain, while its strategic framework is set to channel up to £5.4 billion of contracts over the next decade. That gives the scheme a second layer beyond the asset build itself, with cable, civils, switchgear, substation, and engineering contractors all tied into a longer procurement horizon.
The programme sits within the company’s RIIO-T3 business plan, and it marks one of the largest network reinforcement programmes now moving from planning into delivery in the UK transmission market.
