Costs of Undergrounding
In 2012, the Institution of Engineering and Technology (IET) published an important independent report. This gives an unbiased comparison between the costs of different types of electricity transmission connections, including overhead lines, underground cables and subsea high voltage direct current (HVDC).
The report concludes that there are significant cost differences between the choices we have for the proposed Bramford to Twinstead Connection. It finds that the costs for overhead lines, underground cables, subsea cables and gas insulated lines, for example, are broadly in line with the estimates provided by National Grid.
The report clearly sets out how much more expensive the alternatives are to overhead lines, so we will continue to focus on where particularly sensitive locations justify the higher cost of undergrounding.
View the report here
How does the independent report compare to National Grid’s view?