A multi-million pound project by Scottish Hydro Electric Transmission (SHE Transmission) and SP Energy Networks to reinforce the electricity network on the Kintyre peninsula in Argyll to Hunterston in North Ayrshire has been completed in just under three years.
The challenging construction required an investment of £197 million along with a multi-disciplined and technically skilled workforce to successfully deliver its three main elements:
New grid substations built in the forest at Crossaig on Kintyre and Hunterston Power Station on the North Ayrshire coast
The replacement of 14km of 132kV overhead line connecting the Crossaig and Carradale substations, and finally
The construction of an underground cable connection between Crossaig substation and Port a’Mhidair, where the cable becomes buried beneath the sea bed and runs across the Kilbrannan Sound around the north of Arran before connecting again onshore at Ardneil Bay in North Ayrshire; a distance of some 41km
The majority of the project has been located in SHE Transmission’s licensed area which covers the north of Scotland, with the final part of the works, where 3.5km of land cable was needed to connect the line at Ardneil Bay to Hunterston, being carried out by SP Energy Networks. To reduce construction impacts, SP Energy Networks installed this section using the same route as the Western Link, a further subsea cable project currently being installed that will increase the flow of power between Scotland, England and Wales.
Director of SHE Transmission, Dave Gardner said: “The different aspects of this project involving power lines that travel overhead, underground and beneath the sea bed have raised some interesting challenges, and we’ve been very fortunate to have had the guidance of fisheries, marine and military organisations from the inception of these works.
“The completion and energisation of this part of the network gives renewable developers the capacity to build further generation in this area and, importantly, builds a stronger power supply for those who live and work here. We only need to look back to March 2012 when storms and snow brought this area and the Isle of Arran to a standstill, leaving thousands of our customers without power and further reinforcing our determination to upgrade this network to make it stronger for the many householders and businesses that rely on it.
“I’d particularly like to thank the residents and their community groups, not only for their patience and understanding during these works, but for the way they embraced the project; seeking information from the earliest consultations, providing feedback and ultimately involving us in their community events - such as the Carradale Canter and the Harbour Day - which we were so proud to be part of.”
Pearse Murray, Transmission Director, SP Energy Networks said: "This was a highly complex project delivered ahead of time, and another good example of transmission companies working in partnership to deliver strategically important upgrades to the network in Scotland.
"As well as increasing security of electricity supply supplies, the new link will also provide new capacity and ensure that renewable energy generated in Kintyre can be transmitted to areas of demand in south and central Scotland and beyond.”
Stuart Irvine, the Chair of East Kintyre Community Council added: “It was so reassuring to see that, during these most recent storms, we had only the tiniest flicker to our lights and nothing more; no outage and that’s a huge improvement.
“While the project was ongoing, we were aware of increased traffic on the single track road between Campbeltown and Crossaig, which was leading to damage and potholes but when SHE Transmission recognised the problem they set about repairing and maintaining it; even introducing more passing places and increasing the size of existing ones. These improvements – along with other small, local projects they helped with - will benefit the community for many years to come and we are most grateful to SHE Transmission.”
The Kintyre-Hunterston project has been completed on time and on budget and, in addition to providing a more secure electricity supply to the area by strengthening the transmission network it will allow additional capacity for generators of renewable energy to connect to the grid. With immediate the new links allow the boundary capacity to rise to 420MW to enable the connection of current and future wind, hydro and solar generation developments.