Introduction: There may be a need for network reinforcement on the islands of Lewis and Harris stemming from a requirement to provide improved voltage regulation as a result of potential additional renewable generation schemes on the islands. As indicated by network studies, this may need to take the form of distribution connected, fast acting voltage / reactive response devices. SHETL’s initial studies confirm the existing voltage regulation on the 33/ 132kV tap-changers at Ardmore, Harris and Stornoway are inadequate and too slow to support the output changes associated with additional connected generation capacity.

Objectives: Assess the capability of the existing Western Isles link and identify any potential enhancements to accept additional renewable generation capacity.