Advice for developers on planning electricity grid infrastructure

Check if you need to consult NRW

Use the consultation topics list to see if your scheme requires formal consultation.
Review all relevant guidance on the NRW website before making contact.

Engage early

We offer a free preliminary opinion on your development.

If you need more detailed advice before you apply, you can use our Discretionary Advice Service (there is a charge for this service and our capacity to provide this advice is limited). Our discretionary advice service can help:

Identify sensitive areas before you invest in design and surveys
Avoid placing infrastructure where environmental constraints will make consent difficult or impossible
Meet all relevant legal and policy requirements

You may also need other permissions for your development.

Principles to adopt when planning electricity infrastructure

Choose the right location.

Avoid statutory designations (protected nature areas, scheduled ancient woodland, peatlands, and flood plains) and sensitive coastal or marine habitats.

Avoid designated landscapes. Find designated landscapes on DataMapWales website
Avoid areas of sensitive groundwater such as groundwater source protection zones. Find groundwater sensitivities on our map of environmental data
Avoid woodlands and commercial forests. Find commercial forests on our map of environmental data

Place cables underground where possible, (at a sufficient depth that they will not become exposed by watercourses) especially in protected areas or where collision risk to birds is high. If undergrounding cables is not proposed, you should demonstrate why it has been ruled out.

To minimise the development’s footprint consider co-locating with existing infrastructure where safe and feasible.

Assess environmental impacts

In order to minimise the visual impact on landscape of the installation of grid components, we recommend:

Avoiding adverse impact.
Reducing/mitigating the effects of any impact.
Providing compensatory measures for any harm caused.
Enhancing the visual amenity of any impacts.

We expect developers to apply the approach set out in Welsh Government Planning Policy Wales Edition 12, known as step-wise when considering where to locate grid infrastructure and when managing impacts that arise during construction.

Download Planning Policy Wales Edition 12 from gov.wales

Landscape sensitivity

We encourage applicants to carefully consider pylon design to avoid visibility impacts of sensitive skylines.

Conduct a landscape sensitivity assessment at an early stage to inform route choices avoiding adverse landscape impacts.

Siting transmission lines

New transmission lines should be sited in accordance with National Grid guidelines, known as the Holford rules.

Underground cables are preferred however if this is not possible and pylons are used, the choice of pylon design should minimise the visual effect on the landscape.

Download guidelines for siting transmission lines (the Holford rules) from the National Grid website

Siting and designing sub-stations

The siting and design of new sub-stations should be in accordance with National Grid guidelines known as the Horlock rules.

Download guidelines for the siting and design of sub-stations (the Horlock rules) from the National Grid website

Survey for protected species and habitats

A number of species are protected by law. A protected species licence is required for any work that affects a protected species in Wales.

Generally, you should:

Avoid harm or disturbance to protected species as far as possible.
Carry out surveys to establish the presence of protected species and an assessment of the likely impact on a protected species by an ecologist.
Consider the habitat requirements, range and seasonality of any protected species with a view to mitigating harm or disturbance.
Consider whether alternative routes are feasible.

Read our guide to bat licences for development and infrastructure

Ancient woodland

Ancient woodland must be avoided.

Peatland

Infrastructure should not be located on areas of peat soil or thinner deposits of peat of functional significance to adjoining deep peat, or where these support semi-natural peatland habitat.

Consideration should be given to the impact of infrastructure on adjacent areas of peat and ensuring that these areas are not damaged.

Flood and erosion risk

You should factor in future flood risk and climate change effects.

Climate change predictions for Wales are for increased frequency and intensity of storms and heavy rainfall events, leading to increased flooding, erosion and storm damage. It is essential that electricity grid infrastructure is built to withstand the climate of the future to ensure resilience of supply.

Proposals must not cause or exacerbate flood risk elsewhere and demonstrate that the risks and consequences can be managed.

New cables must not be located where they could interfere with NRW’s flood maintenance activities.

New infrastructure must also not be in areas likely to undergo fluvial erosion.

Find High level fluvial erosion mapping on the British Geological Society website BGS GeoScour Premium

Floodplain erosion can be extensive and sufficient space should be retained adjacent to watercourses to allow for natural channel erosion and migration across floodplains.

A geomorphologist should be consulted to assess the potential extent and degree of current and future fluvial erosion.

This assessment should inform the location of any new development.

Reducing the risk of flooding and erosion and taking account of climate adaptation can be done by:

Following the Welsh Government’s Technical Advice Note 15: Development, flooding and coastal erosion (TAN 15).
Locating infrastructure away from areas at risk of flooding as much as possible, and outside Flood Zones 3 and 2. See the Flood map for planning.
Undergrounding cables at an appropriate depth as much as possible to avoid the risk of storm damage, lightning strike, fires, and decreased efficiencies caused by higher temperatures in heatwaves. Cables should be at an appropriate depth to avoid exposure from lateral river erosion.
Where undergrounding is not possible, installing higher power line poles, conductors with hotter operating limits or implementing the use of ‘low-sag’ conductors, and increasing the minimum design temperature of new overhead line routes should all be considered.
Ensure pylons are located outside of floodplains and areas at risk of erosion.

A flood risk activity permit (FRAP) is required for works on or near a main river, flood defence asset or floodplain.

Waste minimisation

All planning applications are supported by information to demonstrate how they minimise waste.

The quantity of waste generated during the construction and subsequent decommissioning phase should be kept to a minimum.

Circular economy principles should be adopted, leading to greater reuse and recycling of materials.

We expect plans to demonstrate:

Waste be designed out during the project planning phase.
Adoption of a circular approach and consider end of life options for materials to be used.
Using a site waste management plan.
Undertaking waste minimisation audits during the construction and decommissioning phase.
Following the waste hierarchy.

Offshore cables

Almost the entire coastline of Wales is designated for environmental protection.

Anything below the Mean High-Water Springs is subject to marine licensing.

Further help

energyadvice@naturalresourceswales.gov.uk

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