Grid Connections for Scottish Renewable Generators

21 Mar 2019

In Scotland, onshore wind remains the predominant generation type, making up approximately 59% of registered grid scale generation.

An increasing number of developers believe that subsidy-free wind projects are feasible, thus the trend in onshore wind generation growth is likely to continue. Other renewable technologies are seeing an uptake in interest including offshore wind (Crown Estate Scotland’s upcoming ScotWind Leasing round), the developing marine energy sector and a somewhat surprising growth in large scale Solar PV.

There is concern about the ability of existing transmission infrastructure in Scotland to facilitate the scale of connections required to cater for this growth. The, now operational, Moray Firth – Caithness HVDC link, while providing a route for power from wind farms in the north of Scotland to flow south, hasn’t helped in resolving the well documented bottleneck between Scotland and England. The planned Peterhead – Drax link and onshore reinforcements, such as the East Coast 400kV incremental reinforcement programme (which has been given an initial go ahead by the System Operator) will also be important for the connection of further generation.

Whilst is likely that traditional wide-scale reinforcements will still be deployed to make these connections, there has been a noticeable shift away from this approach to more “no – build” connection solutions. Most connection constraints stem from thermal capacity limits of network assets. The Scottish Transmission Owners (TOs) recognise that the evolving energy system requires innovative solutions to deal with these issues.

These innovative solutions are typically techno – commercial in nature, such as the Generator Energy Management Scheme (GEMS) and the increasingly wide-spread use of Active Network Management (ANM) schemes, which balance the potential for restricted network access with reduced connection costs.

While the industry is seeing these changes being slowly implemented, the way users pay for operation and maintenance of the network is undergoing a major change. Split across two programmes; the Targeted Charging Review (TCR) and the Network Access and Forward-Looking Signals Project set out Ofgem’s preferred changes and a path to implementation between 2021(-) AND 2023. There is uncertainty about the specifics of these plans and the net effect on the different types of network user and while the final decision hasn’t been made (summer 2019), it is likely that they will result in higher use of system costs for Scottish generators.

The perception amongst developers is that despite notable efforts to improve network access and asset utilisation, the slow pace of change, regulatory uncertainty and inconsistent and complex charging policies all mean that significant obstacles to the deployment of renewables in Scotland remain.

Key contact

Alex Ikonic, Graduate Consultant

Alex Ikonic

Technical Consultant

Alex has an MEng in Electrical Engineering with Renewable Energy from the University of Edinburgh. She works within the Developer Support Team on a range of grid connections projects, regularly advising developers on grid connection strategies, and project construction timescales and costs for both distribution and transmission connections. She has worked on a number of capacity searches across DNO areas, covering different technologies and connection capacities. She often liaises with DNOs and NGET to help progress projects and has helped clients with connection applications. Her focus has primarily been on onshore wind but she has worked on solar, battery storage, marine energy and EV projects. Alex also oversees in-house cost estimation tools for grid connections which are used in feasibility and due diligence work, as well as having recently become involved with the DCUSA project.