7. Introduction to BESS
This section contains information and guidance on battery electrical storage systems (BESS).
It aims to achieve development which is well-integrated into the landscape and minimises visual impact, whilst conserving and enhancing valued landscape features and characteristics.
It also identifies circumstances where BESS development would be at odds with the intrinsic undeveloped character of the landscape or the special qualities of Protected Landscapes (or both).
7.1 What are BESS?
BESS are devices that store surplus energy from renewable sources (such as solar and wind) then release it when the power is needed most. They enable homes and businesses to be powered by renewable energy when the sun isn’t shining or the wind is not blowing.
Traditionally, fossil fuel-driven power stations have been used to manage peaks and troughs in electricity demand and output, but as fossil fuel power stations are phased out, BESS will become increasingly important.
They are a relatively new technology and land-use but are likely to become increasingly common over the coming years.
Sometimes BESS are used in association with other energy storage solutions such as synchronous convertors. These are more likely to look like regular buildings (agricultural or industrial sheds) and are therefore not covered by this guidance.
The materials used in BESS have a limited working life, and at the end of this will need to be either replaced or removed and the site restored as set out in the Landscape and Ecology Management Plan or Decommissioning Plan.
7.2 Components of a BESS scheme
There is no fixed size for a BESS, which typically comprises an array of lithium-ion batteries stored in racks within metal modules or in containers which resemble shipping containers approx. 12m long, 2.5m wide and 3m high. They are cooled by fans to minimise safety risks.
The containers are arranged on an area of hardstanding, with a control building and other electrical components.
Due to the hum of the cooling fans, it may be necessary to provide acoustic screening (bunding or fencing) in some locations.
Fencing and CCTV are required for site safety and security.
7.3 Optimum locations
Because of the nature of the scheme, proximity to a National Grid substation is a key driver of location. Some BESS may be associated with wind farms or solar PV arrays.
A BESS site also needs to be accessible by the lorries used to deliver the ready-made components to site.
Sites are often in close proximity to large energy users (such as on industrial estates) but may also be in rural locations if it is possible to connect to a suitable National Grid substation.
7.4 Potential landscape and visual issues
A number of landscape and visual effects can arise from BESS development. The following list covers some of the principal landscape issues that designs will need to address, and demonstrate an appropriate response to, when making an application:
- The introduction of solid surfacing and regular-shaped modules or containers with an industrial character into a rural landscape can lead to a loss of intrinsic rural character.
- Modules or containers of a light colour will be particularly noticeable, particularly when seen in a predominantly green and natural setting.
- Acoustic bunding and other earthworks (for example to create access or level the site) may intrude on views.
- Urban features such as black-top tarmac, concrete kerbs and utilitarian buildings can add to the sense of urbanisation of the countryside.
- Construction of the BESS can result in impacts on, or the loss of, landscape features such mature trees and hedges, or contours through site levelling.
- If poorly designed or sited, BESS can damage the setting of designated heritage assets or non-designated heritage assets such as historic tracks or field patterns which form the edges to historic settlements.
- BESS may be particularly visible in long views when located on a hillside or when looked down on from high ground.
- Access, ancillary buildings and security requirements (such as fencing and/or CCTV) may introduce new and unfamiliar features into the rural landscape
- Access tracks may be highly visible, particularly in open or undeveloped landscapes that currently may not contain such infrastructure.
- Grid connections might involve the removal of landscape features and/or might detract from the rural character of the landscape.
- Designated landscapes such as National Parks and Areas of Outstanding Natural Beauty (National Landscapes) are likely to be particularly sensitive. Extreme care therefore needs to be taken to ensure the siting of BESS does not affect the special qualities of designated landscapes, views in and out of protected landscapes, and their settings.
- Noise from inverters and cooling technology may reduce tranquillity and/or require acoustic fencing or bunding which may in itself be visually intrusive.
8. Guidance on siting and designing BESS development in Devon
This section starts with general considerations when identifying potential locations for solar BESS development, before addressing more detailed design considerations. For all schemes, the ability to connect to a National Grid substation will also be a key consideration when identifying potential sites.
It should be noted that as this guidance relates primarily to landscape, there will be other matters, such as impacts on heritage assets, ecology and access that need to be taken into account in site selection, design and decision-making.
8.1 Protected Landscapes (National Parks and AONBs/National Landscapes)
Areas designated as National Parks and AONBs/National Landscapes are legally protected. Under national planning policy, the scale and extent of development within designated areas should be should be limited, and development within their setting should be sensitivity located and designed to avoid or minimise adverse impacts on the designated areas.
Major development should only be permitted within designated areas in exceptional circumstances. See Part E for more detail, and on protected landscapes within Devon.
Relevant authorities have a duty ‘to seek to further the statutory purposes of National Parks and National Landscapes through Section 245 of the Levelling Up and Regeneration Act 2023’. This may include proposals within their setting which may affect views in and out of them.
There is a need to consult with relevant National Park Authority or National Landscape regarding proposals which may be outside their boundaries but within their settings.
If a scheme’s LVIA demonstrates that the proposals will conserve and enhance natural beauty then they can be accommodated even in protected landscapes.
8.2 Urban and brownfield sites
Provided that a suitable connection to a National Grid substation is available, sites with an existing industrial character should be prioritised for BESS, followed by brownfield sites. Greenfield sites in open countryside should be the last sites to be considered.
Reclaimed or man-made landscapes (such as former quarry sites) may also be suitable for BESS developments.
8.3 Transport of components
It is important to consider the practicalities of transporting components to the site.
Some components (such as battery storage units) come as fixed-size units and cannot be dismantled for transport.
The site therefore needs to be accessible by large vehicles transporting these components without damage to historic lanes or hedgebanks, or the removal of roadside trees.
8.4 Landscape considerations
Once the general location for a scheme has been identified, it is necessary to undertake careful detailed design in order to minimise and mitigate its effects on the landscape and views as much as possible.
Alternative site layouts should be investigated to compare the effects of different designs and to find the optimum layout and design of a BESS development.
It is also important to contact the local Planning Authority as early as possible for pre-application discussions, so their advice can be taken on board from the earliest stages. This will save time and money in the long run.
The following diagram shows the landscape-related issues which should be considered when designing a BESS development. Guidance on each topic is provided in the following sections.
8.5 Fitting into the existing landscape structure
Landscape structure is formed primarily by woodland, hedges and trees. A BESS development should fit into the existing landscape structure.
The development should fit into an existing field/land parcel without requiring the removal of existing trees, woodland or field boundaries.
If the BESS development site is only taking up part of a field or land parcel, then new boundaries and woodland can be created to enhance the landscape structure and provide screening of the site.
Avoid siting components which are separate from the rest of the group.
8.6 Relating to landform
In general terms, BESS usually fit best into relatively flat landforms, such as plateaux, lowlands and broad valleys. Steep slopes and ridge landforms are least able to successfully accommodate BESS developments due to their visual prominence.
- Flat sites such as valley floors (outside floodplains) and very shallow slopes on lower valley sides can often accommodate BESS developments more comfortably than higher or steeper slopes.
- Plateau-top sites can work well for BESS development (provided that they are not looked-down on from higher land) but it is necessary to set structures back from the edge of the plateau so they don’t appear on the skyline when viewed from below.
- If it is necessary to use a sloping site, ensure the modules/containers follow contours.
8.7 Respecting valued landscape features
Employ a qualified landscape architect and/or consult the relevant Landscape Character Assessment and Local Plan (and Neighbourhood Plan, if applicable), to understand which landscape features in the local area are highly valued and therefore should be protected.
Some of these valued features will be designated for their landscape, nature conservation or cultural heritage value.
Other valued features may not be designated but are still important, such as, for example, distinctive skylines, historic field patterns, hedges and hedgebanks, key views, and landscapes with a strong sense of wildness or remoteness.
However, all could be adversely affected by poorly-sited or designed BESS development.
It is also necessary to think about the potential impacts of cabling works on valued landscape features.
It is unlikely that trenches will be permitted in areas with existing or potential archaeological features, or in locations with valued habitats which would be affected by cable trenches.
Locate and design the scheme to protect cultural heritage features, heritage assets and (in the case of – for example – Scheduled Monuments, Listed Buildings, Registered Historic Parks and Gardens and Conservation Areas) and their settings. A setting is the surroundings in which a designated site is experienced. It may include views to or from the designated site. Landscape character therefore often contributes the settings of heritage assets.
Consult the Devon Historic Environment Team at an early stage to identify the need for archaeological work and potential mitigation measures through site design, as bases for BESS, and auxiliary elements such as site compounds, access tracks, fencing and cable runs may impact on buried archaeology.
Protect areas valued for their remoteness, wildness and perceived lack of human influence, such as upland moorland, and areas of undeveloped coast.
Some historic field patterns have intrinsic historic landscape character significance or potential for preserved archaeological evidence, and are therefore unlikely to be suitable sites for BESS development. Use the Devon Historic Landscape Characterisation to identify the types of fields within the site. Areas shown as rough ground with earlier remains; prehistoric fields; watermeadows; strip fields and medieval enclosures should generally be avoided. Some more recent but discrete enclosed landscapes may also be sensitive, such as Barton fields, particularly when associated with a Listed historic farmstead.
Locate and design the scheme to avoid damage to designated natural heritage sites such as Special Areas of Conservation, Special Protection Areas, Sites of Special Scientific Interest, County Wildlife Sites, Regionally Important Geological Sites and Ancient Woodland.
Seek opportunities to enhance cultural landscape features, for example through landscape design or Biodiversity Net Gain measures which enhance assets such as parkland, woodland or meadows, or which take archaeological sites out of cultivation.
8.8 Trees, woodland, hedges and habitats
Most landscapes in Devon have hedges, trees and woodland cover which may help to screen BESS development and assimilate it into the landscape; the exceptions are generally open moorland and coast.
BESS development is relatively low (about 3m high, although acoustic fencing may be higher) so it is relatively easy to screen using woodland, trees, hedges and hedgebanks. These may be existing or planted as part of the scheme.
There are also opportunities to extend or create new habitats as part of the scheme design.
Native trees and important landmark trees should not be felled to accommodate BESS development. Other ecologically-valuable landcover should be protected and not be lost through development. Within Devon this includes moorland, culm grassland, heath, meadow and marsh.
Trees (in woodland, copses, alongside roads, in hedges and in fields) are hugely important to Devon’s landscape character, and to its biodiversity. This is also true of the network of hedges and hedgebanks which create Devon’s distinctive ‘patchwork’ of fields. The BESS development (and associated cabling) should therefore be designed to retain existing trees, hedges and hedgebanks.
New hedgebanks, hedges and woodland can be created around the peripheries of BESS developments to help screen them from surrounding roads, footpaths and properties.
Refer to the Local Nature Recovery Strategy to identify suitable habitat enhancements for a particular site.
A Landscape Enhancement Management Plan should be prepared as part of the planning application, showing how landscape and biodiversity features are retained and enhanced through the scheme. Refer to the Devon Local Nature Recovery Strategy when preparing the Landscape Enhancement and Management Plan.
8.9 Considering views, viewpoints and the settings of protected landscapes
Visit all parts of the potential site, and look around you. Is it possible to see any roads, footpaths, houses, known viewpoints (marked on Ordnance Survey Maps) or land within National Parks or AONBs/National Landscapes?
If any are visible from the site, then it is likely that the site will be visible from them. Particular care will therefore need to be taken in the design of the scheme to ensure that its visual impact from these places is minimised. This may require re-siting of the scheme, and/or mitigation in the form of new native tree, hedge or woodland planting.
It is particularly difficult to mitigate when a site is looked down on in views from above, so if a site is located below an important viewpoint it may be necessary to consider an alternative site.
Where a footpath passes close to the site, it is necessary to carefully consider the relative heights of people on the footpath, existing or new hedges, and the containers and auxiliary structures within the site. Setting back structures at a greater distance from the hedge will also reduce their visibility from the footpath.
In some cases it may be possible to allow existing hedges to grow out to screen views of the BESS development from footpaths or other viewpoints. However, this should only be done where it fits with local landscape character, restores traditional management practices and does not result in deterioration of the hedge.
If a scheme is within or in the setting of a National Park or National Landscape, be mindful that there is a legal duty of care on relevant authorities to ‘seek to further the purposes’ of the protected landscape.
Development within their setting should be sensitively located and designed to avoid or minimise impacts on the designated area and be consistent with the protected landscape purposes. See Part E for more detail on this, and on protected landscapes within Devon.
Additional measures to help fulfil the aims and objectives of the protected landscape’s Management Plan may also be required. This may include, for example, woodland planting or habitat creation.
8.10 Getting the colour and detail right
The colour and reflectivity of BESS components makes a big difference to their visibility in the landscape.
Choosing the right colour therefore reduces the landscape and visual effects of the scheme, and helps to reduce cumulative impacts.
Paying attention to details (such as access tracks) can reduce the visibility of the scheme and help it to fit into its rural surroundings.
Use recessive colours such as dark greys and browns (greens – surprisingly – are less good) rather than light colours for battery modules or containers, auxiliary structures and fencing. There may also be opportunities for innovative solutions involving ‘wrapping’ buildings in vines or using cladding.
Steel security fencing should be dark in colour. Timber palisade or close-boarded fencing appears very visually prominent and should not be used.
Where an acoustic barrier is required, earth mounding is generally preferable to a solid fence. The mounding or fence should be screened by tree planting to reduce its visual impact.
Use native trees, woodland, hedgebanks or hedges to screen structures, earthworks and security fencing. There is likely to be an offset of 4m required between fence and hedge.
Allow the existing field patterns to dictate the size of the scheme and the layout of the modules or containers. Avoid straight edges to blocks of modules or containers in fields which are irregular in shape.
Light pollution should be avoided. If lighting is required, use passive infra-red (PIR) lighting where possible, and ensure that any visible lighting is designed and installed in a manner which minimises glare or light-spill into the surrounding landscape. This is particularly important in areas which currently have dark night skies.
If CCTV is required, poles should not be higher than surrounding fencing, and should be mounted on timber poles, or metal poles painted a recessive colour.
Grid connection cabling should ideally be under existing roads. If trenching for cables is required, it should use existing gateways and minimise damage to trees and hedges. If damage is unavoidable, features should be reinstated like-for-like on completion of the scheme.
Undertake the necessary archaeological surveys before digging cable trenches.
8.11 Access considerations
If it is necessary to construct new access tracks, use existing gateways where possible and aim to avoid removal of trees and hedges. If damage is unavoidable, features should be reinstated like-for-like on completion of the scheme.
Consider vegetated surfacing or temporary roadway matting for tracks, rather than hardcore or other solid surfacing.
Avoid urban-style materials such as black-top tarmac and concrete kerbs on tracks and hardstanding.
8.12 Minimising cumulative impacts
Cumulative impacts may occur where more than one BESS development is visible in a view, or where a series of developments occur along a road, public right of way or recreational route such as the Tarka Trail, for example.
They can result from schemes clustering around National Grid connection points and substations. They may also appear as cumulative impacts with nearby solar PV schemes.
A number of measures can be taken to reduce the severity of cumulative impacts, as follows:
- Scheme designs should consider how the scheme fits with other existing, consented and proposed schemes (including within neighbouring planning authorities) to minimise cumulative effects.
- Use battery modules or containers of similar size and design for all schemes which will be seen in the same view, and when extending a scheme (unless the initial scheme is not considered to fit well into the landscape, for example, through the use of light coloured structures).
- Individual BESS developments should generally appear separate unless specifically designed to create the appearance of a single combined development.
- Ensure that each BESS fits within the existing landscape structure, and utilise native vegetation to screen each site as much as possible.
- Consider views from settlements when siting and designing multiple BESS developments so that settlements do not become surrounded.
8.13 Summary checklist
Landscape considerations
BESS are more likely have an acceptable or less harmful impact on the landscape if they:
- are located outside nationally important landscapes and their settings (although small-scale schemes may be acceptable depending on local circumstances, location and scheme design)
- are not located within valued landscape, or within landcover perceived to be natural such as moorland
- are not detrimental to the intrinsic character or beauty of the countryside
- are on previously-developed land or within an industrial/developed context
- are proportional to the scale of the surrounding landform and field patterns
- respect existing topography, and avoid cut and fill
- are sited on flat land or shallow slopes rather than steep slopes
- do not harm existing vegetation (including mature hedges or trees), protected habitats, and avoid peat soils
- do not result in the loss of mature hedges or trees
- are not detrimental to a sense of remoteness, wildness or tranquillity
- do not damage historic lanes/tracks, hedges, hedgebanks or other historic or archaeological features (potential impacts within the site and through access and cabling should be considered through archaeological investigation)
Visual considerations
BESS are more likely have an acceptable or less harmful impact on the landscape if they are:
- seen in the context of other built development of a similar scale
- screened in key views by existing vegetation, or by vegetation or hedgebanks or bunding designed into the scheme
- sited to avoid visibility on skylines
- not detrimental to key views of landmarks or views from popular viewpoints
Design considerations
BESS are more likely have an acceptable or less harmful impact on the landscape if they:
- have battery storage units and ancillary structures (including fencing) painted in a recessive colour (preferably olive green, brown or dark grey)
- have bunding and fencing screened by native vegetation (particularly in rural locations)
- do not introduce urbanising features such as black top tarmac or concrete kerbs into rural locations
- promote enhancements to biodiversity and habitat connectivity
Cumulative impacts
Do not have unacceptable cumulative impacts with other existing, consented or planned renewable energy schemes.