Overhead Or Underground? Further evidence has been published on the undergrounding debate
Green GEN Cymru remains committed to transparency in the ongoing debate around the undergrounding of power lines. We have consistently pledged to both the public and government to provide robust, evidence-based information to support informed decision-making.
In May, we published a report by Turner & Townsend that examined our proposed routes in detail. Their analysis indicated that undergrounding our lines would be on average 4.5 times more expensive than overhead lines. For our Towy Usk project, this would translate to approximately £0.5 billion in additional cost.
Green GEN Cymru like all grid companies is regulated by Ofgem to design economic and efficient networks, crucially this is because the costs of building grid infrastructure in the UK is ultimately passed on to the energy bill payers.
To add such significant costs to new grid routes in Wales would not only impact people’s energy’s bills but may well render future customer connections unviable, with both new generators and new demand customers such as businesses and communities required to pay connection costs that would be significantly greater. Not only will this impact Wales’ ability to decarbonise but also its ability to attract investment and remain economically competitive with the rest of the UK.
When we launched the report by Turner and Townsend, we also noted to the public that further analysis was underway. We’re now pleased to share our latest report, produced by DNV, a globally respected authority in testing, certification, and technical advisory services.
This report offers a comprehensive comparison between undergrounding and overhead line options, taking into account not only cost, but also environmental impact, power capabilities, Sustainability, flexibility and effects on local communities. It also reviews the cable plough technology, which we understand has generated significant interest. Notably, DNV does not recommend this technology for 132kV lines – conclusion echoed by cabling experts CCI.
We recognise the strength of feeling on this issue and we want to do what we can to support. That’s why Green GEN Cymru is currently the only Distribution Network Operator conducting detailed, comparative assessments of undergrounding versus overhead options.
You can a links to our previous reports below.
DNV a globally respected authority in testing, certification, and technical advisory services. DNV-Undergrounding-132kV-Assessment-Report.pdf
Turner and Townsend are global leaders in independent programme, project and costings analysis. They considered inputs provided by UGC and OHL supply chain companies including cable ploughing providers who provided input on installing UGC with cable plough technology to compare to open-cut trench installation.
Forecast-Costs-and-Comparison-of-Underground-Cables-and-Overhead-line.pdf
Cable Constructing International (CCI) are experts in UGC system design. They have previously worked with companies such as National Grid, Scottish Power and SSE.
