Capturing Oxfordshire sunshine … with extra community benefits

24 Apr Capturing Oxfordshire sunshine … with extra community benefits

Sunlight and grazing sheep … plus new woodlands, wild meadows, hedgerows and enhanced natural biodiversity. Add 49.9MW of annual clean green energy for local and national use and the result is a project that will help the UK to meet its 2050 net-zero climate change commitments, but also safeguard a much-loved county environment.

Solar farms are a growing feature of the British landscape as the UK transitions to low-carbon energy with some 40% of UK power coming from solar, wind, biomass and hydropower sources in 2022 (https://www.weforum.org/agenda/2023/01/2022-renewable-energy-uk-electricity/). However, wider considerations are also extremely important.

It’s good to talk …

The success of the Tar Farm proposal near Stanton Harcourt, West Oxfordshire, owes much to detailed discussions we led between residents, planners, and the site developer, to modify plans sympathetically around local concerns. As a result, benefits for everyone were optimised.

I thought it would be useful to sketch out how we helped to make this happen, the project’s parameters, our assessment and survey work, plus the goodwill created with local stakeholders.

Enzygo’s liaison role

While resolving technical issues, Enzygo (www.enzygo.com) as the project’s planning consultant and environmental consultant was also able to gain full local authority planning permission to install a 49.9MW solar farm on what hitherto has been rural farm land.

The terms of consent mean that for the next 40 years the site will have the potential to generate vital low-carbon renewable electricity. At the same time, the land’s use for pastoral grazing and cereal crop cultivation will continue – with sheep known to shelter from the hot sun in the shadow of solar panels!

Meanwhile, mitigating steps were agreed to blend the facility into the landscape and provide an upgrading network of important public rights of way.

The result is a textbook example of how the combined expertise of Enzygo’s multi-disciplinary technical and design team members – some with extensive public sector experience – plus our negotiating skills, led to a solution that addresses the wants and concerns of all stakeholders.

Dual mission

Solar energy has a promising future. In ‘Summoning up the energy’ on 2020 (https://enzygo.com/news/summoning-up-the-energy/) we looked at the use of increasingly efficient materials to manufacture solar panels.

More adventurously, solar energy could eventually be harvested in space by Solar Power Satellites (SPS), converted into radio frequency waves, and beamed down to ground surface (https://www.theengineer.co.uk/content/in-depth/next-generation-could-space-based-solar-farms-solve-our-energy-woes and https://www.esa.int/Enabling_Support/Space_Engineering_Technology/SOLARIS/SOLARIS2). However, current developments are more down to earth!

Dual mission

West Oxfordshire District Council (WODC) has two important priorities. In 2019, it declared a ‘climate emergency’, pledging to become net zero by 2030 and encouraging others in the district to follow suit, with the aim of delivering climate change mitigation through energy security while providing enough energy for local users and farm diversification.

Its other goal is to protect the local environment. For this particular example, that includes the interests of people and wildlife, with a focus on any visual impacts the temporary infrastructure could cause. A key concern was the experience of footpath users who will be shielded by both well-established and newly-planted trees and hedgerows.

The project ethos of our client, Bluefield Renewable Development Ltd which owns and operates more than 100 solar assets, was not to gain planning permission at any cost but work in partnership with community stakeholders.

For example, by listening to local concerns, we were able to recommend that some areas of higher ground be turned into areas of important biodiversity gain. I will list the agreed concession points later.

Physical parameters

After careful consideration by WODC’s Lowlands Area Planning Sub-Committee, full permission was granted to construct, maintain and decommission a ground-mounted solar PV farm and associated infrastructure at Tar Farm that will operate under current projections for 40 years from the date of first electricity export. Installation will take nine months.

For England, the onshore solar farm capacity threshold set out in Section 15 of the Planning 2008 Act is 50MW. Proposals larger than this are considered to be Nationally Significant Infrastructure and need a Development Consent Order from the Secretary of State.

Solar Energy UK (https://solarenergyuk.org/) says that, based on an average annual consumption of 3,300kWh/household, every 5MW of installed solar farm capacity will power approximately 1,500 homes – and crucially save 2,150 tonnes of carbon annually.

Tar Farm is a 49.9MW project on 84.4 hectares (208.5 acres) of land that could supply the equivalent of 15,000 homes.

This ties in well with WODC’s Local Plan 2011 to 2031 which requires a minimum of 15,950 new homes – solar power could supply circa 94%, albeit indirectly through the local distribution network.

Environmental parameters

The development will be on land Identified as ‘more suitable’ for solar farm projects comprising ten irregular field parcels with hedgerow boundaries and trees in many small woodland blocks in and around the site which is described as being set in a rural landscape with gentle undulations.

The nearest settlement – South Leigh, south west of Witney – is a village with dispersed homes well-screened from the site. Tar Wood is an Ancient and semi-Natural Woodland with no ecological designations.

Very importantly, biodiversity net gain (BNG) – the legal requirement for the natural environment to be left in a measurably better state than it was before – will be carried out in accordance with the National Planning Policy Framework (NPPF) and Local Planning Policy (https://www.local.gov.uk/pas/topics/environment/biodiversity-net-gain-local-authorities).

The site will be enclosed by a 2.5m perimeter high deer fence with gaps to allow smaller mammals through.

No existing trees and hedgerows will be removed, except for alterations to the gateway entrance. Where additional planting takes place, rich grasses and wildflowers will be used to support biodiversity. Wildlife corridors will be created via new hedgerows and tree planting. Grassland biodiversity will also be improved with organic management.

Environment Agency flood risk maps show the site to be in low-risk Flood Zone 1, described as ‘entirely appropriate’ for a solar PV (photovoltaic) farm.

Technical details

A major issue with new UK renewable energy developments is their capacity to connect them to the national power grid. A suitable connection for Tar Farm is offsite at Witney substation north of Ducklington village. It will be reached by buried cables.

Non-reflective PV panels laid out east to west will have 4m to 6m spacing to avoid shading each other. They will also be inclined at 15 to 25 degrees to the sun. Upper edges will be up to 2.8m above ground level; lower edges will be 0.8m off the ground.

Cabling linking panel arrays to transformers and 11 inverters – which convert direct current (DC) into alternating current (AC) electricity – will be buried in 1.5m deep trenches.

There will also be a single 2.25m tall substation in a site compound secured by a 2.5m high steel mesh fence; inverters will be in green metal cabinets and mounted on a concrete slab foundation.

Addressing community concerns

Local people understandably worry about new developments in their area. With Enzygo’s experience of technical, environmental and community matters, our brief included identifying reasonable planning concessions that could be made around residents’ concerns that were represented by South Leigh Parish Council (SLPC). I will come back to this in a moment.

As a backdrop however, it was important to point out that only limited impacts are anticipated.

While harvesting the sun’s energy, the facility will create no noise. No pollution or waste will be released into the local environment. The site will be unmanned except for occasional maintenance work.

However, the consultation team looked closely at all potential aspects that might need mitigation – ecology, landscape, visual, transport, agricultural land classification, heritage, archaeology, community involvement, flood risk, trees and hedgerows, glint and glare.

– Ecological Impact Assessment (EcIA)

Enzygo carried out the EcIA through detailed site visits and desk studies as per guidelines in the WODC’s pre-application requirements. This included a breeding bird survey, plus the eDNA (ecological DNA) testing of ponds to confirm whether great crested newts were present. Three ponds tested positive.

A habitation survey was completed at optimal survey times. We looked carefully at buffer zones to protect wildlife and bird areas, as well as risks and safeguards for bats, plus arable field margins, and specifically protected birds, common reptiles, and priority species.

Our conclusion was that there are significant opportunities for biodiversity enhancement for overall BNG improvements. Good landscape management could see a minimum 10% net gain in wildflower grasslands, with new border hedgerow planting, bat boxes, bird boxes, and informal hibernacula (winter shelters for dormant animals).

– Landscape and Visual Impact Assessment (LVIA)

Enzygo also provided a LVIA that considered the development’s impacts on the local landscape, given that it is temporary and reversible. The local landscape is characterised as ‘moderate adverse’.

The loss of an area of arable agricultural land, but introduction of significant planting, is seen as ‘minor adverse’. Indigenous species of local provenance will be planted. Three areas of ecological mitigation will include a mosaic of grassland and woodland habitats.

Most receptors (i.e. people) will experience no change of view. Existing footpaths will be widened with new hedges, trees, and wildflowers added to help screen off close up views of solar panels.

– Geo Environmental Phase 1 Site Report

We were able to show here that there are no contamination risks on site or surrounding, and no environmental hazards.

– Flood Risk Assessment (FRA)

Our FRA and outline site drainage strategy for the site which is classified as ‘essential infrastructure’ showed it to be Flood Zone 1 (low-risk) which is ‘entirely acceptable’. Solar panels are ‘water compatible’.

Specifically, fluvial (river) flooding risks are negligible, ground water risks low, and surface water flooding risks also negligible for most of the site.

How concessions were negotiated

Although objections were raised by parishioners about views, proximity to the village, and project size, SLPC saw the proposal as an opportunity for ‘dynamic negotiations’ with the developer.

Having commended the applicant for ‘listening, adapting and reducing the scale’, SLPC members decided not to oppose the plan because of the concessions made.

The first phase includes the redesigning of footpaths with a minimum buffer of 10m along footpath corridors, plus a significant widening northeast of the scheme. The minimum width will now be 13.5m, broadening out to 29.5m as the view opens out towards the village. Fence line repositioning at some points will allow expanded areas of planting.

As mentioned above, two northeast parcels of rising ground near the village have also been removed from the solar site and turned into an extra 5.26ha of Biodiversity Enhancement Area.

Case studies

– North Yorkshire

We recently helped to secure consents for a Voltalia UK Ltd 32MW solar scheme in Scarborough providing power for up to 9,600 homes, with CO2 savings of more than 13,500 tonnes annually. Again, the plans included associated infrastructure, access and landscaping.

– Chelmsford City Centre

We were similarly successful south east of Chelmsford City Centre, Essex, where electricity generated by a solar farm will be transmitted via a private wire connection to Essex & Suffolk Water’s Hanningfield Water Treatment Works.

The comprehensive application package included landscaping works, ecological and biodiversity benefits, plus seasonal grazing for farm animals (https://enzygo.com/consultations/canonbarnsroadsolarfarm/).

If you would like to discuss any of the issues raised above, please contact me directly.

Rob Gandy, Principal Planning Consultant, Enzygo Ltd