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Here you can find answers to some of the most frequently asked questions about the Green GEN Towy Usk project.

Green Generation Energy Networks Cymru (Green GEN Cymru) is based in Wales and is developing green energy networks in Wales to meet the future needs of Welsh people, communities, and businesses.

Green GEN Cymru will design, build, and operate a new 132kV (132,000- volt) distribution network needed to connect new Welsh renewable energy projects to the electricity transmission network, helping to get green energy to homes and businesses across Wales and beyond.

Our green grid network can provide a regional network solution for South and Mid Wales. Renewable energy generators will be able to apply to connect to it, reducing the need for more infrastructure in future. It also has the potential to support technologies like 5G that could help farmers, schools, and businesses to be at the cutting edge of technology while being based in a rural area. The connection could open up potential for business investment in the area and support the creation of jobs and skills and the transition from fossil fuels to renewable energy for heating homes and electric vehicles.

We will work closely with Welsh communities and stakeholders as we develop our plans, to maximise the benefits and minimise the impacts for local people. You can find out more at the Green GEN Cymru website

The Green GEN Towy Usk proposal is for a new 132kV connection, approximately 97 kilometres in length between the Nant Mithil Energy Park in Powys and a new substation, to be developed by National Grid, on the existing 400kV (400,000-volt) transmission line near Llandyfaelog, in Carmarthenshire.

Our original proposal was for a double-circuit overhead line, carried on steel pylons, throughout the route. Following feedback received in our first round of consultation in spring 2023, along with further technical and environmental assessments, we have revised our plans.

Green GEN Towy Usk will link Bute Energy's Nant Mithil Energy Park, which will generate clean, green energy in the Radnor Forest area, to the national grid.

Other green energy projects, including Bute Energy's proposed Aberedw, and Bryn Gilwern Energy Parks will also be able to connect to the proposed Green GEN Towy Usk line, reducing the amount of additional infrastructure needed in future. It is anticipated that the two energy parks will use single-circuit overhead lines supported on wood poles to connect to Green GEN Towy Usk.

Bute Energy's portfolio of onshore wind farms, solar PV projects and co-located battery energy storage systems could have an installed capacity in excess of 3GW by 2030, making a substantial contribution towards meeting the renewable energy targets of the Welsh Government and the Net Zero carbon objectives of the UK Government.

For more information on the energy parks proposed by Bute Energy, please visit their website

  • Following the first round of consultation in spring 2023 we re-examined our preferred route from an environmental, technical, and economic perspective to see if we could make changes based on the feedback received and our own further assessments and site visits.

    We looked at where we could make changes to the route, and reviewed where we might be able to change the proposed technology and infrastructure (such as where it may be more appropriate to use wood poles or underground cables instead of steel pylons). Following this work, we identified a draft route alignment (including potential pole and pylon positions) within the reviewed preferred route.

    The draft route alignment takes account of the 2,949 feedback responses we received from communities and stakeholders, and includes consideration of biodiversity, the landscape and views, cultural heritage, woodlands, flood risk, geology and soils, other land uses, and technical needs.

    In summary the changes include:

    · a single-circuit overhead line supported on wood poles between Nant Mithil Energy Park and a new switching station at the foot of Aberedw Hill;

    · a section of underground cable where the route crosses the River Towy near Llanarthney, and;

    · some alterations to the route in other places.

    A summary of what changes have been made in each section of route is provided below.

Changes in Section 1: Nant Mithil Energy Park to Aberedw Hill

Following assessments, it has been determined that the section between Nant Mithil Energy Park and Aberedw Hill can be supported on wood poles, meaning that steel pylons are not needed on this section of the route.

The switching station can also accommodate energy from the proposed Aberedw and Bryn Gilwern Energy Parks, which are at an earlier stage of development. These would also be able to connect to the switching station using single 132kV circuits, likely supported on wood poles.

Locating the switching station at the foot of Aberedw Hill allows all three proposed energy parks to connect at the same point, thereby reducing the need for additional infrastructure that would have been required if they were to connect to the network in different places.

The proposed route has been moved further away from Franksbridge than originally proposed, to increase the distance from the village.

Changes in Section 2: Aberedw Hill to Llangammarch Wells

Changes to the proposed route to reduce potential effects on ancient woodland, residential properties, and priority habitats; and landscape and visual effects where the River Wye is crossed.

Changes in Section 3: Llangammarch Wells to Llandovery

Changes to the proposed route to reduce visual effects at Cefn-gorwydd; and the introduction of two potential route options in the Crychan Forest area (options A and B), giving the potential to reduce potential effects on commercial woodland.

Changes in Section 4: Llandovery to Llandeilo

By following a route to the north of the River Towy, we have been able to reduce potential effects on the Towy Valley and Bannau Brycheiniog National Park, as well as visual effects at and around Llandovery and Felindre, and visual and heritage effects at and around Llangadog.

Changes in Section 5: Llandeilo to Llandyfaelog

Use of underground cables instead of an overhead line where the draft route alignment crosses the Towy Valley. At the end of Section 5, the proposed route has been moved further east to avoid the existing 132kV line and residential properties, and to reflect the proposed location for the National Grid substation.

The overhead line in section 1 of the route will be supported on wood poles.

These wood H-poles are typically 12.8 metres tall and 127 metres apart. Examples of which can be seen below.

The exact heights of the wood poles and distances between them will depend on ground conditions, topography or where the connection needs to cross roads or railways where a taller pole may be required to achieve the required clearance.

Following feedback received in the first round of consultation, and our own further technical and environmental studies, we are now proposing to use underground cables rather than overhead lines where the draft route alignment crosses the River Towy in Section 5 of the route, a length of about 5.5 kilometres.

In reaching this decision we considered how an overhead line might have significant effects on the landscape and views of the special landscape area, particularly around Paxton Tower and Dryslwyn Castle. We have also considered potential effects on breeding and wintering birds on the River Towy SSSI and wider Towy floodplain, including geese, swans, ducks, gulls, and waders.

Using underground cables to cross this particularly sensitive area would reduce the potential for effects on the views, landscape and wildlife.

The underground cables would pass beneath the main A40 road and the River Towy at a point where they are close to each other, allowing us to minimise disruption to both the road and the river and complete the route in the most efficient way.

High voltage, high capacity overhead lines are the proven economic and reliable choice for the bulk transmission of electricity throughout the world.

Green GEN has applied to Ofgem for an Independent Distribution Network Operators Licence (IDNO) to allow it to transport electricity. IDNO licence holders have duties contained in section 9 of the Electricity Act 1989 to develop and maintain an efficient, coordinated, and economical system of electricity distribution and this will be scrutinised both in the planning process and by the energy regulator, Ofgem. Green GEN Cymru will have a duty under the IDNO licence to ensure costs are minimised and as a result, will need to balance carefully the impacts of the proposals with the costs of mitigation.

Following feedback received at the first round of consultation in 2023, we are now proposing to cross the River Towy near Llanarthney in Section 5 of the project using underground cables rather than overhead lines, to reduce the potential for effects on the views and landscape.

The wood pole line proposed in Section 1 of the route will terminate at the proposed new switching station near the A481 at the foot of Aberedw Hill.

A switching station is similar in appearance to an electrical substation and will be approximately 75m x 85m in size to accommodate the electrical equipment needed. An example of which can be seen below.

The switching station will also need access roads, fencing and environmental measures including landscaping. The proposed site has good access from the main A481 road, it is relatively flat, and it does not have any environmental designations.

The switching station will also be the end point for connections from the proposed Aberedw and Bryn Gilwern Energy Parks. This allows us to connect three proposed Energy Parks in one place, at a location that we believe has a lower impact on the environment and local communities than other potential sites and reduce the amount of infrastructure overall.

From the switching station near the A481 at the foot of Aberedw Hill, a new double-circuit 132kV overhead line supported on steel pylons will be required to transport the energy onwards to join the national grid network.

The standard height for a steel lattice pylon to carry a 132kV overhead line is typically 27 metres. The average span length (the distance between pylons) is approximately 250m. The exact heights and distances will depend on ground conditions, topography or where the connection needs to cross roads or railways.

In this second round of public consultation (Wednesday 13 March to Wednesday 8 May 2024), we are asking for your feedback on:

· Any factors you think we should consider when developing our proposals for the draft route alignment, including the proposed locations of pylons, wood poles, underground cables and switching station.

· Your views on whether we should select Option A or Option B for the draft route alignment in the Crychan Forest area (section 3 map).

· Any factors you feel have not been considered in our work to date that will help us identify any potential issues and finalise our detailed plans before we prepare our consent applications.

· We'd also like to know if you have ideas on areas in your community that could benefit from investment through Bute Energy's community investment fund.

Please give us your views, even if you have already commented during the first round of consultation in 2023.

A. Our consultation period is now open and will run from Wednesday 13 March to Wednesday 8 May 2024.

You can view an interactive map of our draft route alignment, and further information about this stage of the consultation here on our website. You can view and download materials that provide more information about our proposals for the Towy Usk connection in our Document library

During March and April, we are holding six community events along the proposed route for communities to find out more about the project and to see how we have revised our plans and ask questions of our project team. A computer visualisation of the draft route alignment will be available to see at the events.

Community event information can be seen below:

Community Event Timetable
Location Date and time
Montgomery Pavilion
Royal Welsh Showground, Builth Wells LD2 3SY
Wednesday 20 March
2pm to 7pm
Llanarthney Community Hall
Llanarthney, Carmarthen SA32 8JD
Thursday 21 March
3.30pm to 7.30pm
Llandeilo Fawr Civic Hall
17 Crescent Road, Llandeilo SA19 6HW
Saturday 23 March
11am to 4pm
Penybont District Community Centre
Penybont, near Llandrindod Wells LD1 5UA
Tuesday 9 April
2pm to 7pm
The Castle Hotel
Kings Road, Llandovery SA20 0AP
Wednesday 10 April
2pm to 7pm
Llandyfaelog Community Hall
Carmarthenshire SA17 5PA
Thursday 11 April
2pm to 7pm

We are keen to understand local views, detailed feedback from specialist organisations and communities is a key part of how we will refine our proposals.

Your local knowledge can help us understand any potential effects and benefits that we may not have considered in our work to date, and to inform our work going forward.

There are several ways you can provide your feedback or contact us.


Phone: 0800 3777 339



Please submit your feedback to us by 23:59 on Wednesday 8 May 2024. Any feedback received after this date may not be considered by our team.

All the feedback we receive will be reviewed and carefully considered as we develop our plans.

For more detailed information about our first round of consultation, the feedback we received and our response to the issues raised, please read the Stage 1 Non-Statutory Consultation Report.

Green GEN Cymru will pay for the construction and maintenance of the new electricity distribution network. There will be no public funds used.

We believe that as a Welsh renewable energy business, we are uniquely placed to work with Welsh communities, landowners, stakeholders, and suppliers to create economic and community benefits for Wales. Our green grid network can provide a regional network solution for the Mid Wales region.

The Towy Usk connection will take power from where it is generated, to the existing 400kV (400,000-volt) transmission line near Llandyfaelog, in Carmarthenshire, where it can then be distributed via the national grid, locally and nationally.

A changing climate is having a dramatic effect on plants and animals – protecting biodiversity is one of the key drivers for moving away from fossil fuels.

Meeting the needs of the natural world with the infrastructure we need to address climate change requires careful balance. Developing large infrastructure will always have effects on the environment, but it can also be an opportunity to invest in and enhance biodiversity. We will seek to keep any effects on biodiversity as low as we can in the decisions we make.

To support our application for planning consent to Planning Environment Decisions Wales (PEDW) we will prepare an Environmental Impact Assessment and the outputs of this will be presented in an Environmental Statement (ES). The EIA is an assessment of the proposals on the environment including potential effects on biodiversity, ecology and water. The EIA will identify, predict and evaluate the likely effects of the proposals and identify any mitigation actions to reduce any effects and to provide a positive contribution to the natural environment.

We will comply with current guidelines in Wales on achieving a net benefit for biodiversity within the area. By working closely with the relevant stakeholders, we will work to deliver an environmental benefit that goes above and beyond these requirements – we are committed to achieving at least 10% net gain in biodiversity compared to today.

We are committed to keeping the environmental impact of our proposals as low as we can.

The project's environmental impact will be assessed as part of an Environmental Impact Assessment (EIA) on our final design for the overhead line.

This will investigate the potential environmental impacts of our proposals, together with how we plan to reduce or limit these impacts. This will be reported in the Environmental Statement that is submitted as part of our application for planning permission. We will also work closely with specialist bodies, local environment groups, landowners, and local communities to discuss our findings and consult on our recommendations for how best to manage any potential impacts.

We recognise it's not just about delivering clean, green energy in Wales; it's also about investing in communities and the future of rural Wales.

Bute Energy is committed to paying £7,500 per megawatt installed on all the energy parks it is developing through an independently governed Community Investment Fund. The fund will benefit not just local people close to the energy park sites, but communities along the route of the grid connections too.

Green GEN Towy Usk will connect the Nant Mithil, Aberedw, and Bryn Gilwern Energy Parks to the national grid. If these proposed energy parks are approved, communities along the proposed Towy Usk connection will be eligible to apply to the Bute Energy Investment Fund which has projected value of approximately 2.5 million per annum.

Bute Energy's community investment fund will be directly investing in the communities affected by these proposals and will help to create lasting impact locally ensuring that the benefits of our renewable energy projects are felt by communities across Wales.

Bute Energy have prepared social mapping for the area, talked with local stakeholders and, reviewed feedback from our previous consultation to help them better understand how communities in the area can be supported.

Through feedback from the first round of consultation in spring 2023, engagement with local people and extensive social research, the top 5 place-based challenges identified along the Towy Usk route are:

1. Community Life and Resilience

2. Agriculture

3. Access to transport and transport infrastructure

4. Support local businesses, micro enterprises, and organisations

5. Loneliness and isolation.

We are in the early stages of development of this project and no final decisions have been made on where the connection or the pylons will go.

Once we have a final design we will speak to all landowners affected on a one to one basis and how we can support them. We will work hard to reduce impacts on individual properties but if the final design does impact your property we will discuss what compensation is available to you in line with current legislation. Please contact us if you have a particular concern.

We understand that those affected by our current proposals including homeowners and landowners could have concerns. We're committed to ensuring that any impacts are mitigated as much as possible and are keen for those most affected to give us detailed feedback on the proposals. Our lands team are available to meet with homeowner and landowners. If you have an interest in land affected by our proposals and have not yet been contacted by our land team, please get in touch.

This is our second round of consultation, and we are asking for feedback on the work we have done to date and how we should further develop our proposals. No final decisions have been made on where the infrastructure will go within the draft route alignment.

It is important that people respond to this consultation and tell us their concerns so we can work to reduce the effects on communities and individual properties.

Once we have refined our proposals, we will work with landowners affected to discuss how we can support them. We will work hard to reduce impacts on individual properties but if the final design does impact your property, we will discuss what compensation is available to you in line with current legislation.

If the project is consented, construction will begin in 2026, with clean, green energy distributed to homes and business in Wales by 2028.

Green Gen Cymru is proposing a new 132kV substation to connect to the National Grid 400kV substation at Llandyfaelog, in Carmarthenshire.

The proposed 400kV substation in this location will be owned and operated by National Grid Electricity Transmission (NGET).

The new substation is required to satisfy an increased electricity demand and two generation connection requests in the area from National Grid Electricity Distribution (NGED) and Green GEN Cymru.

The exact location for Green Gen Cymru 132kV substation has not yet been confirmed although it is anticipated this will be sited adjacent to the proposed 400kv substation. The plans for the Green GEN Cymru substation will be included in the DNS application for our Towy Usk grid connection project.

We will use your feedback to review the decisions we've made to date and to inform our work going forwards.

New electricity transmission lines of 132kV are classed as a Development of National Significance (DNS) in Wales. This means developers must apply for planning consent to Planning and Environment Decisions Wales (PEDW) and final decisions are made by the Welsh Ministers.

Feedback from our public consultation and from local authorities, community councils and national organisations will help us develop a final design for the project. We will also carry out further technical assessments and surveys to inform our Environmental Impact Assessment (EIA).

Before we submit a consent application to Planning and Environment Decisions Wales (PEDW), which is expected to be in 2025, there will be a statutory Pre-Application Consultation (PAC) period, where people will be able to review and comment on the detailed designs and the draft Environmental Statement.

High-voltage overhead lines can sometimes generate noise, under certain conditions. This often sounds like either a crackle or humming sound and occurs mainly during wet weather.

Noise may also arise as a result of wind blowing past the line or pylons. Any potential noise impacts will be considered as part of the Environmental Impact Assessment (EIA).

We will always ensure that the design of the overhead line and substation carefully considers any impacts on the local community.

We are committed to causing the least disturbance we can to those living and working in the areas affected by our proposals. We will take advice from technical stakeholders and consider the project's impact on local roads as part of a traffic and transport assessment, which is a requirement of the process we will follow to submit a planning application.

This will include how we plan to manage construction traffic, including any potential impacts. We recognise the importance of maintaining connectivity between nearby towns and villages and we will ensure that our work does not make it difficult for those living and working in the area.

A. Electric Magnetic Fields (EMFs) are produced whenever electricity is used or transmitted. Household wiring, appliances and electricity supply are all sources. So, they are around us all the time in modern life. Overhead lines are a source, but just one of many. The maximum possible exposure under the overhead line is 38.9 microtesla, which is similar to what you would expect from using a hairdryer or walking close to a microwave when it's cooking.

There are limits in place to protect us all against EMF exposure. These limits have been based on careful reviews of the science by independent experts, who recommend safe levels of exposure for the public. The exposure limit for members of the public is 360 microtesla, so even if you are standing directly underneath the overhead line, the levels are just a small fraction of the limit.

After many decades of research and hundreds of millions of pounds spent investigating the issue, there are no established health effects below the exposure limits. More information is available at

You can contact the project team at: