Party pledges to ban steel pylons and keep energy profits in Welsh communities if elected in May
PLAID CYMRU has unveiled plans to overhaul how energy infrastructure is delivered in Wales, including a commitment to effectively ban steel pylons for lower-voltage electricity lines if the party wins the Senedd election in May.
The proposals would see a “strong presumption in favour of undergrounding” electricity cables, with overhead lines permitted only where they are supported by low wooden poles or similarly less intrusive infrastructure. Under the plans, steel lattice pylons would not be allowed for any electricity line of 132kV or below.
The party says the policy forms part of a wider ambition to transition Wales to a modern, green energy system while protecting landscapes and communities, particularly in rural areas.
Plaid Cymru has also stated that one of the first acts of a Plaid-led Welsh Government would be to develop a new National Energy Strategy, aimed at ensuring that energy generation benefits Wales directly. Central to this approach is a commitment to “keep energy and profits created in Wales in our communities”.
As part of the proposals, the party would strengthen the planning process for major energy developments. Applications for large onshore wind farms would be required to fully consider cumulative impacts, including associated infrastructure, across all Developments of National Significance.
Developers of energy projects over 10MW would be required to provide a minimum local or community ownership stake of between 15% and 25%, or an equivalent benefit mechanism such as a local benefit model or sovereign wealth-style payment, as a key condition of planning consent. Plaid Cymru says this would ensure communities directly benefit from developments in their areas.
The party also plans to introduce incentives and financial support to encourage energy projects that are led and owned by communities or the Welsh Government.
Further proposals include extending permitted development rights to give households, farms and businesses greater flexibility to install small wind turbines, solar panels on roofs or on the ground, battery storage and heat pumps, while maintaining safeguards for safety, heritage and local amenity.
Plaid Cymru would also amend building regulations to require all new homes and major refurbishment projects to install rooftop solar panels capable of meeting the property’s annual energy demand, unless it can be clearly demonstrated that doing so would not be practical.
A key early step under a Plaid Cymru government would be the issuing of a Ministerial Interim Planning Policy Statement to establish a clear presumption in favour of undergrounding electricity lines between 11kV and 132kV across Wales. Overhead alternatives would only be allowed where low wooden poles or equivalent infrastructure are used.
However, the proposals come against the backdrop of long-standing challenges facing Wales’s electricity network. Wales, particularly mid-Wales, has significant wind power potential, but much of the existing grid was never designed to transport large volumes of electricity from rural and upland areas to demand centres in south Wales or onwards to England. Much of the network is ageing, with some infrastructure dating back close to a century, and requires extensive modernisation to cope with the increased and changing flows of power from renewable sources.
Cost and practicality remain central to the debate. Energy developers and network operators argue that overhead lines supported by pylons remain the most cost-effective way of upgrading the grid. Building overhead lines is significantly cheaper than laying underground or subsea cables, which can cost five to eight times more, with lower construction costs seen as key to keeping consumer energy bills down.
There are also concerns around maintenance and resilience. Pylons are generally quicker and easier to repair than underground cables, with faults often resolved in hours rather than weeks or months. By contrast, failures in underground systems can require extensive excavation, leading to prolonged disruption and higher repair costs.
The issue has already proved contentious in the Senedd. A previous Plaid Cymru motion calling for mandatory undergrounding of power lines was rejected, primarily over concerns about cost and flexibility. Welsh Government ministers argued that while undergrounding is already the preferred option “where possible”, making it an absolute requirement would be unaffordable and could slow or prevent the delivery of renewable energy projects.
The motion was defeated following a tied vote, with the Deputy Llywydd casting the deciding vote against the proposal. Labour MSs said they supported the overall aim of reducing visual and environmental impact but opposed making undergrounding mandatory, warning it would significantly increase costs for consumers and harm economic viability. The Welsh Government instead committed to reviewing existing policy rather than introducing a blanket change.
Industry figures have also warned that undergrounding power lines comes at a significant financial cost. Underground electricity cables in the UK are estimated to cost around 4.5 times more than overhead lines, with major transmission cables at 33kV and 132kV potentially costing between £1.25 million and £2 million per kilometre. For higher-capacity routes, tunnelled infrastructure can push costs dramatically higher, with some projects reaching £820 million for 15 kilometres. Such costs are driven by complex terrain, construction disruption and technical challenges, raising concerns about potential impacts on household energy bills.
Cefin Campbell, the candidate at the top of Plaid Cymru’s list in Sir Gaerfyrddin for the forthcoming Senedd election, said the plans reflected the party’s long-standing commitment to communities and local control.
“I am very proud that Plaid Cymru is at the forefront of supporting our communities and working to keep energy and profits created in Wales in our communities,” he said. “We need to move away from an extractive economy model which has been so damaging to Wales over the centuries.”
Mr Campbell added: “Our position will be clear if we have the privilege of being elected in May – we will not allow pylons to be erected along our valleys to please capitalist companies. Any energy project must take place with the joint involvement of communities and, ideally, under local ownership or Welsh Government ownership.”
