Question to the Department for Energy Security & Net Zero:

To ask the Secretary of State for Energy Security and Net Zero, with reference to the National Policy Statement for Electricity Networks Infrastructure (EN-5), on what evidential basis his Department has determined that overhead lines should be the strong starting presumption for electricity network developments in general.

The starting presumption for electricity network developments set out in EN-5 is based on several factors including cost, environmental and technical points.

Overhead lines are quicker and easier to construct, cause less environmental disturbance during construction, are easier to maintain and repair, and are simpler to connect to existing circuits.

Evidence indicates that overhead lines are significantly cheaper than undergrounding, with the Institution of Engineering and Technology (April 2025) estimating undergrounding costs around four and a half times more.

As these costs are ultimately borne by electricity bill payers, overhead lines remain the Government’s starting presumption.