This site has been identified as having an excellent wind energy resource. It is also not affected by any environmental designations that would prevent the development.

Part of the Site, accommodating 6 of the 30 proposed wind turbines, is identified as a Pre-assessed Wind Priority Area (‘PAA’) in Welsh Government’s Future Wales: The National Plan 2040.

Whilst there is a presumption in favour of large scale renewable energy development within PAAs, there is no restriction on development outside those areas, in fact there is generally a strong in principle planning policy support.

We have carried out a landscape and visual impact assessment (LVIA) to identify the significant landscape and visual effects that are likely to arise as a result of the proposal.

This involved a detailed assessment of key viewpoints within a 28km radius study area of the site, in consultation with the Council’s landscape expert. Every home within 2 km of turbines has been assessed in detail from a residential visual amenity perspective.

We have also assessed the cumulative effect of the proposal in conjunction with other similar developments (with planning permission) within the study area.

The final 30 turbine layout, in comparison to the 36, delivers an improvement in terms of landscape and visual effects, in particular in residential visual amenity impacts on properties to the north, west and south of the site where the nearest homes are located.

Below is a breakdown of the turbines by height:

• Three at 220m
• 24 at 205m and
• Three at 180m.

Larger turbines are becoming industry standard, and this maximum design scenario is needed to ensure the project delivers efficient and affordable electricity. 200m to tip onshore wind turbines are already operational or under construction in the UK, including at Kype Muir,  Longhill Burn and Cumberhead West wind farms, while several other onshore UK wind projects have planning permission granted for turbines of between 220 and 251m to tip.[1]

Larger turbines, specifically larger rotor diameters, increase the efficiency of wind turbines.

[1] Further information can be found here: https://www.gov.uk/government/publications/renewable-energy-planning-database-monthly-extract#full-publication-update-history

The access route crossing the River Wye is no longer being considered.
The Energy Park is located centrally in Wales, so we are considering two route options for deliveries of turbine components into ports located either to the north or south. Access from the north would come through Birkenhead and Cheshire, along the A483 and A44. Access from the south would come through Swansea along the Heads of the Valleys road to the A470, through Herefordshire and along the A44 to the site.

To reflect this, we have included two points of access to the site dependant on which direction deliveries come from. Only one route and one access point will be constructed. The final decision will be taken following feedback with manufacturers, hauliers, road authorities and the police.

Any significant changes needed to the road network along the chosen route would need separate planning permission and would be made in consultation with the Local Authority.

We have extensively surveyed the site, with 17 previously unrecorded historic assets identified in addition to detailed assessment of the known undesignated assets and scheduled monuments.  The site has interesting history stretching from the bronze age in the form of funerary mounds through to less well-known use of the site as a Second World War ‘battle school’.

We have worked to avoid direct physical effects on any undesignated or designated heritage assets.  Our design maintains ‘lines of sight’ between the three scheduled funerary mound monuments, where it is believed there was a visual relationship between them.

Following feedback during the statutory consultation, we have amended the design by moving T25 50m south to remove the rotor swept area from the line of sight between Shepherd’s Tump and Great Rhos Round Barrow scheduled monuments.

Archaeological monitoring and reporting will be required as part of any planning permission.

Through our Historic Environment Plan and Strategic Recreation Framework, we have an opportunity to create a ‘heritage trail’ using a network of signage, information and interpretation points to bring awareness of and access to the fascinating cultural heritage of the site, including using augmented reality and virtual reality.

We undertook a range of ecology surveys between 2020 and 2024 to define the ecological baseline for the Site. The surveys included a Desk Study, Phase 1 habitat surveys, Phase 2 (National Vegetation Classification (NVC)) surveys, bat potential roost assessment surveys, bat activity surveys involving static detectors and surveys for badger, otter, water vole, great crested newt (GCN) and fish.

A Habitat Management Plan for the project will ensure it delivers a net benefit for biodiversity over its lifetime.

Updated surveys are being undertaken in 2025 and further pre-construction surveys will take place as is standard practice.

Planning permission will also be subject to conditions requiring the implementation of a Bat Mitigation and Monitoring Strategy, a Great Crested Newt Mitigation and Enhancement Plan and pre-construction Otter Surveys.

No development is proposed within the SSSI.

The Environmental Statement concludes that impacts on the Radnor Forest SSSI after mitigation are considered to be negligible and not significant.

The outline Habitat Management Plan sets out measures to potentially enhance the Radnor Forest SSSI.

Chapter 10 of the Environmental Statement: Access Traffic and Transport concludes that with the implementation of appropriate mitigation, no significant residual effects are anticipated in respect of access, traffic and transport issues.

During the construction phase, the traffic effects will be minor or negligible as they are temporary and reversible.

During the operational phase, the traffic effects will be low.

We will communicate details of abnormal loads delivery dates and times via a variety of methods in advance to allow journeys to be planned in advance.

A Flood Consequences Assessment and Outline Drainage Strategy have been prepared for the proposed development that sets out how surface water runoff will be managed so as not to result in increased flood risk either on site or elsewhere.

Sustainable Drainage Approval will be required for the project, in addition to planning permission.

We have undertaken desk and site based studies to understand the current, baseline conditions as well as engaging with Welsh Government’s Land Quality Advice Service.

This has involved peat probing to help inform the proposal, which minimises the interaction of infrastructure with areas of peat and specifically deeper peat.

The Outline Soil Management Plan, including Peat (oSMPP) confirms that the presence of peat is limited to small pockets on the Great Rhos plateau (within the SSSI boundary), discrete hollows within the forestry plantation on Esgairnantau and isolated pockets associated with topographical hollows on Nyth-grug and Llan-Evan Hill, and along the Nant Cwm Du.

The oSMPP confirms that all infrastructure has been placed outside of the defined areas of peat and sets out measures to be employed during construction that will minimise and mitigate disturbance to protect soils.

We have undertaken a detailed assessment of theoretical shadow flicker in accordance with guidance. However, whether shadow flicker is actually experienced at a property is dependent on a number of other factors including wind speed and direction, potential shielding/screening effects of buildings, trees, vegetation or other obstacles, orientation for both the property windows and turbines, or whether a room is occupied at the time of occurrence.

We will repeat this exercise post-consent, once ground investigation is completed and the precise location (within the current ‘up to’ 50m micrositing allowance) and the dimensions of the selected turbines are known.

We will follow the established guidance and ensure mitigation will be applied where the following thresholds are exceeded:

• ‘30 minutes per day’ – understood to be an exceedance of 30 minutes of shadow flicker experienced by an individual property in any one day of the year; and
• ‘30 hours per year’ – understood to be the total occurrence of shadow flicker throughout the year experienced by an individual property.

If any of the residents experience significant shadow flicker effects at their property, this will be investigated and mitigation like vegetation planting can be explored. Alternatively, if residents experience shadow flicker that can’t be mitigated by other means, then the relevant turbine(s) can be shut down at those times of greatest impact.

The carbon costs of the project will be paid back after approximately 1.4 years of operation, through the displacement of a fossil fuel mix of energy generation in the National Grid.  Operation of the Energy Park will have a significant positive effect on saving CO₂ and NOx emissions.

We have compared the carbon costs of the proposal (typically generated during construction) with the carbon savings attributable to the proposal. This assessment is informed by the Scottish Governments Carbon Calculator Tool (v1.1.8) to estimate the carbon emission savings associated with the proposal. The tool was produced by the Scottish Environment Protection Agency (SEPA) to assess the impact of wind farm developments upon peatland in relation to the release of carbon from affected peat resource.

As required by Regulation 5 of the EIA Regulations, the Environmental Statement considers the possible effects that a proposal may have in combination with existing or consented developments. In accordance with the Planning Inspectorate’s guidance for Nationally Significant Infrastructure Projects, a staged process for assessing schemes has been adopted, as requested by PEDW.

The Environmental Statement provides an assessment of the proposal and its cumulative effects on the natural, built and human environments, on a chapter-by-chapter basis and within Chapter 15: Summary of Interrelated Cumulative Effects and Likely Significant Effects.

Mitigation measures have been proposed to reduce any cumulative effects of the Energy Park as set out within Table 15.2 of the Environmental Statement.

The proposal is compatible with agriculture, occupying a relatively small surface area of the Site, enabling grazing and other agricultural practices to take place.

In order to provide net benefit for biodiversity, some areas for habitat management will be created and grazing management will be required at specific times of the year.

We have reviewed several studies regarding the impact on tourism of onshore wind in the UK. This research concludes there is little evidence that wind farms have had or are having a negative effect on tourism.

We have undertaken a review of studies into the potential effect of onshore wind on house prices. It finds that there is no clear evidence that supports a correlation between wind farms and a consistent negative effect on house prices.

Several public rights of way (PROWs) cross the site. In siting turbines, we have sought to work with stakeholders and landowners to keep the effects to a minimum.

During the construction phase there may be some need to reroute. If this is required, we will apply for relevant consents and ensure communities are kept informed. Following completion all existing PROWs will be restored.

We are seeking to enhance access and provision for recreation around the Energy Park. and Strategic Recreation Framework has been prepared outlining potential options that can be developed further in consultation with stakeholders.

It is common for farmers to continue rearing and grazing livestock and/or grow crops on land where wind turbines are located. There are also many examples of land next to and below wind turbines being used for a range of recreational activities, from walking and running, to cycling and horse riding.

During the construction period there may be a need to be manage access and limitations placed on the types of activities which could take place across the site at times for safety reasons. However, once construction is complete and the energy park is operational, activities which take place on the site will be able to return to normal.

The site has areas of open access land within it. Open access land will remain unaffected in terms of the right to roam, except for small areas where the wind turbine structures are located as this would constitute ‘excepted land’. However, people will be able to wander right up to the turbine towers in these locations, if they wish.

We have also identified potential opportunities for enhancing recreational access in the Strategic Recreational Framework.  Any future recreational enhancements will be undertaken in collaboration with stakeholders.

Cowlod Common is located centrally within the Site. No wind turbines as proposed within this area, only tracks, associated drainage and underground cabling.

We have the agreement to undertake works on the Common with the relevant freeholder and discussed with the Commoners with rights to graze the land. Replacement Common Land has been identified to offset the improvements being proposed to the existing byway open to all traffic (BOAT) through it and additional track proposed within this area. Common Land Consent is being sought as part of the application.

In Mid Wales, the existing electricity network does not have the capacity to connect all the planned new clean green energy to homes and businesses – to end the use of fossil fuels we need new infrastructure and quickly. There are also significant challenges with meeting future energy demand without investment in modern grid infrastructure.

It is established practice for energy generator projects to come first before grid solutions. Site specific requirements of energy generation projects dictate their location while transmission and distribution projects are required to transfer the energy to where it is used.

Green GEN Cymru has proposed the Towy Usk grid line, a new 132kV electricity connection that will transport energy from Nant Mithil Energy Park and other renewable energy projects to the to the national grid near Llandyfaelog, Carmarthenshire.

This new network is needed to connect new Welsh renewable energy to the electricity transmission network, helping to get green energy to homes and businesses across Wales and beyond.

The latest plans for Green GEN Towy Usk show that the power generated by Nant Mithil Energy Park will can be transported on a single 132kV circuit likely on wood pole as far as Aberedw Hill (approximately 11.3km), where a switching station can transfer it to a steel pylon double circuit.

Green GEN Towy Usk is subject to a separate planning application and more details can be found at www.greengentowyusk.com.

We have a development pipeline that can deliver over 2.2GW of onshore wind by 2030 – helping Wales reach its targets of energy use from renewable sources.

Bute’s first Development of National Significance (DNS) planning application for the Twyn Hywel Energy Park received planning permission from the Welsh Minister in November 2024.

Our energy park projects are all at different stages in the development process and are all forecast to be generating clean green energy by 2030. If consented, our parks across Wales will deliver 25% of the green energy that the Welsh Government says we need to get to Net Zero, playing a pivotal role in meeting their target for 100% renewable electricity in Wales by 2035.

More information about our other Energy Parks is available at: https://bute.energy/

Welsh Government has set a target for 100% of Wales’ electricity demand to be met by renewable sources by 2035. In 2022, 59% of Wales’ electricity demand was met from renewable sources.

To achieve 100% renewable electricity Wales needs:

• Onshore wind doubled by 2035[1].
• Solar PV capacity to triple by 2035 compared to 2022.
• Offshore wind to increase more than sevenfold.
• This requires the right enabling actions and a quadrupling of renewables deployment in just over 10 years.

Wind energy is variable; however it is one part of a collection of technologies generating and storing energy generated by renewable sources. As onshore wind represents the most cost effective and quickest route to generating more renewable energy, it is a key part of achieving government clean energy targets by 2030 and 2035.  The development of Nant Mithil Energy Park will help to contribute to these targets.

[1] Regen analysis https://www.regen.co.uk/exploring-progress-towards-the-welsh-governments-energy-targets-and-their-future-evolution/. National Grid ESO, FES 2022; WPD DFES, 2021; SPEN DFES, 2021; CCC 6th Carbon budget, 2019.

As the generating capacity of the proposed Energy Park is more than 10MW, it falls under the planning category of a Development of National Significance (DNS).

DNS applications are submitted to Planning and Environment Decisions Wales (PEDW) where they are examined by an Inspector before the final decision is made by Welsh Ministers.

The DNS application was submitted to PEDW in late 2024 and accepted in November 2025. The application is available to view on its website: planningcasework.service.gov.wales/ by searching reference number CAS-01907-D7Q6Z1.

Powys County Council is a key statutory consultee and prepared a Local Impact Report for PEDW on the application.

Throughout the development of the project, we have consulted with the Civil Aviation Authority (CAA), National Air Traffic Services (NATS) and Ministry of Defence (MoD) to inform our proposals and impacts on aviation. We will continue to work closely with these organisations to ensure that any impacts to their organisations are minimised and mitigated.

The project is currently subject to a conditional aviation radar objection. We intend to enter into a mutually agreeable process with NATS for assessing potential technical mitigation options in relation to the radar at Clee Hill. Engagement in connection with this is ongoing, and any mitigation would be subject to further technical assessment and agreement between relevant parties.

We have considered the potential impact of the project on wireless communication (telecommunication) links. Telecommunication links are, generally, amenable to mitigation, much of which takes place after a project is granted planning permission. Arquiva, which looks after BBC, ITV and the majority of UK radio companies, has confirmed that they have no objection. The Joint Radio Company (JRC) confirmed that they have no objection to the project in mid-2024 during statutory pre-application consultation. We are working with the JRC to understand its change in position and are seeking to agree mitigation actions. Details on our plans to mitigate risks around telecommunications can be found within the Telecommunications Impact Assessment which was submitted as part of the Environmental Statement (Appendix 2.4). As some providers do not engage in mitigation solutions until after a project has been granted permission, we plan to submit a telecommunications strategy for approval by the Local Planning Authority (Powys Council) before any turbines are erected. The strategy will identify reasonable technical mitigation for the services operated by Airwave, BT, MBNL, Vodafone and JRC, where necessary.