The breakthrough comes thanks to the main Distribution Network Operator agreeing to relax restrictions on solar after STA Scotland lobbied them to analyse several case study connections which, after further calculations and consideration, showed the modest network impact of most rooftop solar projects in practice.
Analysis by the network operator Scottish Power Energy Networks on data provided by STA Scotland members across a range of solar installations concluded that the effect of most on the local grid was much less than previously thought. SPEN had required a ‘Statement of Works’ from developers seeking to install even small solar projects over 11kW.
This meant developers had to commission a costly and time-consuming analysis of how projects may affect transmission loads at national level, adding over £10,000 to some project costs. Also, where fault levels are high on the network, SPEN also confirmed they would only consider these in connections over 200kW, although voltage rise calculations will still apply.
STA Scotland Chair Chris Clark said; “This is a breakthrough for solar in much of Scotland and it goes a long way towards removing one of several barriers to Scotland realising its solar potential. We’re grateful to Scottish Power Energy Networks for engaging with our members and for looking carefully at the evidence. As a result of SPEN taking a sensible approach to rooftop schemes, businesses and housing developers in Scotland will find it easier & cheaper to go solar. Developers, consultants and architects can now look again at solar as a solution to making their buildings more efficient.”
The decision will have a significant, material impact on the economics and attractiveness of going solar, particularly for the commercial rooftop and multi-scheme new build housing sectors. The STA has been holding meetings with Distribution Network Operators in Scotland on the impact of outages and curtailment on solar PV projects.
Chris Clark said; “We look forward to deepening our collaboration with SPEN as the networks transition to smart, active Distribution System Operators able to make full use of the many services and potential cost savings solar PV and energy storage can deliver.”