1. Introduction to wind energy
This section contains considerations and guidance for wind turbine development.
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 wind turbine development would be at odds with the intrinsic undeveloped character of the landscape or the special qualities of Protected Landscapes (or both).
1.1 Size of turbines
A wide range of wind turbines are available to suit different purposes and locations. For the purposes of this guidance, turbines have been divided into four categories based on their size and current typical usage.
Turbines of approx. 200 to 500kW output or less (‘small turbines’) are generally smaller than 50m in height to blade tip. They are typically installed as single turbines as community schemes, or to power individual businesses such as farms.
They may be purchased new, or second hand from schemes which are being replaced with larger or more efficient models (termed ‘repowering’).
A Devon example is the single turbine owned by South Brent Community Energy, which has a blade tip height of 45m.
There are many examples of ‘very small’ turbines accommodated within Devon’s landscape which provide power to individual properties and are 20m high or less.
Turbines of approx. 500kW to 1MW output (‘medium turbines’) are generally 50-100m in height to blade tip. Again, they are typically installed as single turbines as community schemes or to power individual businesses.
Without subsidy, a turbine over approx. 50m high will usually require connection to the grid to make it viable unless the user requires large amounts of on-site electricity. New and second-hand models are available.
A Devon example is found at Mullacott Cross, where three turbines 79m high have been installed on an industrial estate.
Turbines of approx. 1MW to 2MW output (‘large turbines’) are generally 100-150m in height to blade tip. They may be installed as single turbines or as a group (known as a ‘wind farm’).
Commercial examples in Devon include Batsworthy Cross (102m high) Fullabrook (110m high) and Denbrook (120m high). All of these were installed a number of years ago and are smaller than turbines typically used in commercial schemes today.
Large turbines may also be installed by community groups, possibly in partnership with renewables companies.
Turbines of approx. 5MW output (‘very large turbines’) are generally 150-250m in height to blade tip. There are currently no examples of this size of turbine in Devon.
In Scotland, (where applications are well above those in England1) the majority of windfarm applications now comprise schemes of between 11-20 turbines with the turbines 200m+ high to blade tip. However, due to long lead-in times there are not yet any operational examples.
The materials used in wind turbines have a limited working life, and at the end of this will need to be either replaced (repowered) or removed and the site restored as set out in the Landscape and Ecology Management Plan or Decommissioning Plan.
1.2 Components of a wind energy scheme
All onshore wind energy schemes, whether a single farm-based turbine or a commercial wind farm, will require the following typical components:
- Access tracks for construction and operation. These may comprise existing farm or forest tracks with the construction of new tracks between each turbine also necessary for larger schemes. Larger commercial wind farms may also feature borrow pits for track construction.
- Foundations for the turbines usually take the form of buried concrete bases. Further bases may be required for cranes during the construction process.
- Wind turbines which have a similar design but comprise models with different features. Variation is greatest for smaller turbines <50m where two-bladed models or lattice towers may be available. Transformer housing may be outside or inside the turbine. Larger turbines >150m are likely to feature visible aviation lighting on the nacelle and potentially also on towers.
- Temporary construction compounds will be a requirement with the size of these usually commensurate with the size of the development.
- Commercial wind farm developments will require a sub-station or control building which usually comprises a single storey pre-fabricated building set within a fenced compound.
- Off-site development components for larger wind energy developments may include road widening works to accommodate delivery of turbines. Connections to the national grid (via underground or above ground cables) will also be required.
In addition to the above infrastructure, wind farms are increasingly incorporating Battery Energy Storage Systems (BESS). These help to even out the peaks and troughs associated with wind energy supply and demand.
These systems are usually housed in steel containers approx. 12m long, x 2.5m wide and 3m high, with a similar appearance to shipping containers.
Solar energy generation is also increasingly forming a component of wind farm developments, with ground-mounted arrays often located close to the wind turbines and access tracks.
1.3 Potential landscape and visual issues (wind turbines >100m)
This size of turbine (and particularly commercial wind turbines which are commonly >150m high) are substantial vertical structures that will be highly visible within the landscape.
It is not possible to avoid significant effects on character and views from wind turbines of this size although careful siting can reduce intrusion, for example, where landform or woodland screens turbine towers. Larger wind turbines or wind farm developments can affect the landscape in the following ways:
Construction effects
Construction of turbines and associated infrastructure may result in direct loss of landscape features off-site. This may include road widening, junction improvements, new water course crossings and removal of vegetation that may be necessary to transport larger turbine components to site.
This is a particular issue for rural lanes where Devon hedge banks and hedgerow trees are distinct and valued features of the wider landscape. Built features such as existing bridges and walls may also be affected.
Construction of new access tracks and widening of any existing farm or forest tracks between turbines can contribute to the landscape and visual effects of the development, particularly where these are aligned on steeper terrain where cuttings and embankments may result in greater disturbance and intrusion.
Operational effects
The presence of wind turbines and ancillary development can increase the influence of built development in the landscape and may diminish the perception of naturalness and seclusion associated with some landscapes.
Wind turbines can appear to overwhelm smaller scale landscapes and can adversely contrast with particularly complex landform or landcover pattern (or both).
Effects on views may include the interruption of pronounced skylines (for example, Dartmoor’s and Exmoor’s sweeping upland moorland skylines, and highly-visible ridges with historic landmarks such as the Raddon Hills).
The presence of turbines may deflect from existing focal points in views, disrupting the scenic harmony of a view or, if seen in close proximity, obstruction or dominance of views (or both).
The movement of turbine blades may contribute to adverse effects on views and erosion of tranquillity depending on the distance of the viewer.
Turbines may also impact on the settings of protected landscapes.
On-site access tracks and other ancillary components such as solar arrays may be highly visible, particularly in open upland landscapes with little built development or lack of trees or hedges that would afford some screening and integration of built elements into the landscape.
Wind turbines may affect designated heritage assets and their settings, for example, through distracting from views of historic monuments, or appearing in designed views.
They may also affect non-designated heritage assets such as historic lanes and tracks through modifications required to transport components.
Further information may be found in Historic England Advice Note 15: Commercial Renewable Energy and the Historic Environment or any subsequent guidance.
Visible aviation lighting required for turbines >150m high can affect the appreciation of dark skies particularly in sparsely settled and little developed rural areas. More information about dark skies.
1.4 Potential landscape and visual issues (wind turbines <100m)
These are more likely to comprise single turbines associated with a farm, industrial building or possibly a community generation scheme.
This size of development is unlikely to require extensive access tracks, and it may not require a sub-station or control building if not connected to the national grid.
Turbines of this size may, however, be located within more settled landscapes which could increase effects on landscape character and on close views, and may also impact on the settings of protected landscapes.
1.5 Cumulative landscape and visual impacts
The proximity to the grid is a key factor affecting the economic viability of wind turbine developments.
The need for sites to be located close to a suitable grid connection means that proposals are likely to cluster around these grid connection points.
This makes it especially important that the landscape and visual effects of wind turbine proposals are considered not only in isolation but also in terms of the potential cumulative effects with similar proposals and other forms of development.
If unchecked, there is a risk that the cumulative impacts of schemes may lead to them becoming a significant or defining characteristic of the landscape.
Cumulative visual impacts concern the degree to which proposed renewable energy development will become a feature in particular views (or sequences of views), and the impact this has upon the people experiencing those views.
Cumulative visual impacts may arise where two or more of the same type of renewable energy development will be visible from the same point, or will be visible shortly after each other along the same journey.
Hence, it should not be assumed that, just because no other sites will be visible from the proposed development site, the proposal will not create any cumulative impacts.
Sequential views should be considered from roads, public rights of way, and recreational routes (such as the Tarka Trail, for example).
Cumulative visual effects can be particularly marked where a view contains different types and heights of turbine, with different rotor speeds. This leads to a cluttered and confused appearance which distracts from the landscape and views.
The cumulative landscape and visual impacts of wind turbine developments should be considered with each application.
It is necessary to consider cumulative impacts with schemes which are already built, consented schemes, and those in the planning system.
The cumulative effects of proposed wind turbines with other renewable energy schemes within the landscape (such as ground-mounted solar PV and BESS) should also be considered.
2. Landscape sensitivity to wind energy development in Devon
Landscape sensitivity is a measure of the ability of a landscape to accommodate change arising from specified development types or land management without undue negative effects on the landscape and visual baseline and their value.
It combines judgements of the susceptibility of the landscape to change and the values attached to the landscape.
More information can be found in An Approach to Landscape Sensitivity Assessment – to inform spatial planning and land management (Natural England, 2019).
Landscape sensitivity is closely related to landscape character. Devon’s Landscape Character Assessments provide the evidence base which articulates what the key characteristics, valued attributes and special qualities are for all landscapes in the county.
Further information about landscape character can be found in Part E, section 15.3.
There are existing Landscape Sensitivity Assessments for wind development covering Exmoor National Park, Torridge District, Mid Devon District and for specific wind areas within Teignbridge District.
Recommended criteria to use when undertaking future Landscape Sensitivity Assessments for wind energy in Devon are provided in Part F of this guidance.
3. Guidance on siting and designing wind turbine developments in Devon
This section starts with general considerations before addressing more detailed design. For most schemes, the availability of a grid connection, and suitable wind conditions, will also be key considerations 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.
Schemes are generally more likely to be granted planning permission if they are supported by the local community.
Early engagement with the local community around scheme benefits, location and design may help to achieve this. There may also be opportunities for communities to instigate schemes for local benefit.
3.1 Protected Landscapes (National Parks and AONBs or National Landscapes)
It is necessary to ensure that the location and siting of turbines does not adversely affect the key landscape characteristics and special landscape qualities of Protected Landscapes (National Parks and National Landscapes).
These may include distinctive landform or landcover features or perceptual qualities such as a strong sense of remoteness and wildness (or both).
Areas designated as National Parks and AONBs or National Landscapes are legally protected.
Under national planning policy, the scale and extent of development within designated areas should be limited, and development within their setting should be sensitivity located and designed to avoid or minimise adverse impacts on the protected landscapes.
Major development should only be permitted within Protected Landscapes in exceptional circumstances. See Part E for more detail on this, 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.
3.2 Tranquillity and dark skies
Wind turbines can introduce large structures and movement into landscapes, which can impact on tranquillity. It is therefore preferable to site turbines in areas of lesser tranquillity.
Tranquillity mapping has been carried out by the CPRE.
Within Devon there are two Dark Skies Discovery Sites (at Trinity Hill Local Nature Reserve and Knapp Copse Local Nature Reserve) as well as the International Dark Sky Reserve (the first in Europe) in Exmoor National Park.
Mapping by the CPRE shows much of Devon to have relatively dark night skies. The CPRE dark skies map can be accessed here.
Dark sky areas would therefore be particularly sensitive to aviation warning lighting, which is required on turbines over 150m tall.
3.3 Urban and brownfield sites
Often, wind turbines can be accommodated in developed areas with fewer impacts on landscape character than in rural areas. This is particularly true where there are existing large-scale buildings, such as industrial estates.
Nevertheless, care should be taken to avoid overwhelming the scale of the settlement when seen in views, and also blocking or distracting from views of valued landmarks.
Reclaimed or man-made landscapes (such as former quarry sites) may also be suitable for wind turbine developments.
3.4 Transport of components
It is important to consider the practicalities of transporting components to the site, particularly when turbines are large, and require very large transport vehicles. In these cases, road realignment or removal of roadside banks or vegetation may be required, which can have a significant impact on the character of rural lanes and roads.
The practicalities of site access should therefore be considered early in the scheme. It is almost always preferable for large turbines to be sited close to main roads which can be used to transport the components with minimal modification.
3.5 Landscape considerations
Once the general location of the 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.
It is not usually possible to ‘hide’ a large turbine, but there is still much that can be done to site and scale them as sensitively as possible.
Alternative locations and layouts should be investigated to find the optimum design.
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.
Note that the considerations are sometimes different for single and multiple turbine schemes, and this is reflected in the following guidance.
3.6 Getting the scale right
Landscape scale is made up of two factors: scale of landform and pattern of land use.
Scale of landform relates to the perceived height and horizontal extent of the topography. It is also influenced by the degree of openness or containment created by the topography. For example, a flat plateau or lowland plain will be of a larger scale than a steep-sided valley.
Pattern of land use relates to the containment provided by fields, hedges, or woodland. Low-growing vegetation such as moorland or cereal crops can reinforce the sense of openness.
Individual elements within the landscape (for example, trees or buildings) can form reference points against which other features are perceived and understood.
Devon contains a wide range of landscape scales due to its diverse topography and land uses.
In Devon, the largest scale landscapes are generally found in open moorland and lowland plain landscape types.
The smallest scale landscapes are generally found in narrow valleys and areas of sloping land and intricate field patterns.
Landscape Character Assessments will provide information on the scales of landscapes in the area where the scheme is being considered.
Turbines come in a wide range of sizes, and it is important to choose one which fits with the scale of the surrounding landscape.
Ensure the height of turbines does not overwhelm the scale of hills, ridges or historic monuments.
Consult a landscape sensitivity assessment or engage a qualified landscape architect to determine the suitability of a specific site for different sizes of turbine.
Use of computer-generated wireline visualisations from key viewpoints can help to understand how turbines will appear in relation to existing landform.
Coastal areas are particularly sensitive, as turbines too large in scale can easily overwhelm the perceived size and dominance of cliffs and other coastal features.
When siting multiple or medium or large turbines, select sites in simple regular landscapes with extensive areas of consistent ground cover over landscapes with more complex or irregular land cover patterns, smaller field sizes and landscapes with frequent existing human-scale features (for example, small houses).
Denbrook windfarm currently contains the largest wind turbines in Devon (120m to blade tip). It is located in a wide valley, in a relatively large-scale landscape which balances the size of the turbines. Although the turbines are high, their visibility is reduced by them being set low in the landscape.
3.7 Relating to existing landform
The relationship between wind turbines and the surrounding landform is fundamental to good siting of a scheme. It is, however, quite complex, as there are many things which need to be considered.
Use of computer-generated wireline visualisations from key viewpoints can help to understand how turbines will appear in relation to the existing landform.
Within Devon there are a very wide range of landforms, including rolling hills, undulating plateaux, ridges, isolated hills, broad valleys and coastal cliffs.
Some topographic features within Devon are highly visible or make a strong contribution to landscape character (or both). These are particularly sensitive to wind turbine development (both development on the features themselves, and in locations where the features may be blocked in views or the apparent scale of the feature may be diminished).
Use landscape character assessments to understand which landform features are particularly important to landscape character (see the ‘Respecting valued landscape features’ section below).
Ridges or isolated hills which form skylines are particularly sensitive to wind turbine development, as turbines will appear on the horizon over a wide area.
Visibility of turbines can be reduced by locating them on the side slopes of hills or ridges, at a change in gradient or break of slope, in dips in landform, in valleys or terraces, or in concave landforms.
Undeveloped skyline ridges, rugged landforms, knolls, headlands and other prominent topographic features are particularly sensitive to wind turbine development, so turbines should be located away from these.
Setting turbines (particularly larger turbines) low in the landscape will reduce their perceived height. Because the turbines will be partially screened by landform their visibility is reduced and therefore this lessens landscape and visual impacts.
Groups of turbines should be sited at a similar height within the landform.
Seek to keep a turbine group within one landscape character type (particularly as perceived in sensitive views) so that turbines do not span across marked change in character on the ground, such as changes in topography.
3.8 Respecting valued landscape features
Consult the relevant Landscape Character Assessments and the Local Plan to understand which landscape features in the local area are highly valued and therefore should be protected.
They may include, for example, distinctive skylines, historic field patterns, areas of undeveloped coast, trees and woodlands, sites designated for their nature conservation or cultural heritage value, and landscapes with a strong sense of wildness or remoteness.
All of these could be adversely affected by poorly-sited or designed wind turbine development or associated cabling and access tracks.
Note that potential impacts on designated and non-designated heritage assets will be subject to a Heritage Impact Assessment, and potential impacts on natural heritage sites will be subject to an Ecological Impact Assessment.
Where a scheme has the potential to impact on highly-graded assets such as grade I and II* listed buildings or scheduled monuments, it is advisable to seek pre-application advice from Historic England.
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) 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 to 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. The result of archaeological investigations may require re-siting of turbines or cabling to avoid impacts on significant heritage assets with archaeological interest.
Renewable energy schemes may have direct physical impacts on valuable habitats and soils. Areas of carbon-rich peat moorland, peat soils or bog, and irreplaceable habitats such as ancient woodland are not considered to be suitable for renewable energy development.
Protect areas valued for their remoteness, wildness and perceived lack of human influence, such as upland moorland and areas of undeveloped coast.
Protect existing undeveloped ridgelines or skylines, including skylines of elevated coastlines and coastal headlands.
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 wind energy 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.
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.
3.9 Considering views, viewpoints and protected landscapes and their settings
Wind turbines are large structures, and it is usually impossible to hide them from view. It is therefore important that:
- turbines are sited and designed to prevent significant effects on views from important viewpoints (including views which are integral to the character of Conservation Areas, and designated historic landscapes), popular tourist and scenic routes, and settlements
- wind turbine developments should be sited and designed to consider the visual relationship of turbines with valued landscape features such as church towers, hilltop monuments or lighthouses, and aim to not obscure or distract from views of such features, particularly from sensitive or popular viewpoints – it is generally less distracting to see a substantial part of a turbine rather than blades only
If a scheme is within or in the setting of a National Park or National Landscape, be mindful that there is a legal duty 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 adverse impacts on the designated areas 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.
3.10 Protecting and enhancing landscape character and biodiversity
Wind turbines are large, modern structures, but their assimilation into their landscape context can be improved through early consideration of landscape character and features, and the protection and enhancement of the landscape through sensitive design and land management.
Some landscape and biodiversity enhancement measures, such as hedgerow planting, can potentially also provide mitigation in terms of screening views of the development from residential properties or from roads.
However, as a general rule, new hedges should not be introduced into a landscape where they are not characteristic.
Where possible:
- continue the existing land use underneath the turbines so that the landscape flows underneath and around the turbines – there may also be opportunities to enhance landscape pattern and link land use to adjoining landscapes
- consult the Devon Local Nature Recovery Strategy to identify potential habitat measures which could form part of the scheme (on-site or offsite) – these should form part of the Landscape Enhancement and Management Plan
- provide enhanced management of landscape features, habitats and historic assets as part of a development – consult the objectives set out in the relevant Landscape Character Assessment for guidance on how to do this
- encourage traditional management of farmland within the site, including maintaining small fields, hedges and hedgebanks
- the Landscape Enhancement and Management Plan (See Section 11.0 – Part D) should cover land surrounding or under turbines – it should demonstrate proposed land use and management through the operation phase of the development, and also cover restoration or aftercare following decommissioning
3.11 Auxiliary structures, access and cabling
Access, tracks, cable routes and auxiliary structures need to be considered from the earliest stages of a scheme, and not as an afterthought.
If these features are poorly designed then the negative landscape and visual impacts of a scheme can be considerably greater.
Key factors to consider are:
Renewable energy schemes and their auxiliary development may have direct physical impacts on valuable habitats and soils. Areas of carbon-rich peat moorland, peat soils or bog and irreplaceable habitats such as ancient woodland are not considered to be suitable for renewable energy development, including auxiliary structures, access and cabling.
As mentioned above, choose a site which minimises modification to roads or roadside vegetation in order to get the components to site. This includes modification to historic tracks within the site. It is important to prevent damage to stone walls, hedges, flower rich verges, hedgebanks, roadside trees, historic bridges and gateposts. Repair and replace any features affected ensuring materials and planting are in keeping with local context and character.
New tracks need to be carefully designed and sited. Try to follow existing field boundaries where possible. Follow contours rather than going up steep slopes, even if this requires longer lengths of track. Use existing gateways where possible and avoid removal of trees and hedges. Any new or enlarged hedge openings to facilitate construction access should be reinstated once construction is completed.
Where appropriate (such as where hedges are already a feature of the landscape), plant new native-species hedges alongside access tracks to help them blend into the landscape.
Use a vegetated surfacing or temporary roadway matting rather than a solid surface where possible. Reduce the width of access tracks post-construction using reserved soils and turves.
Avoid urban finishes such as black top tarmac and concrete kerbs.
CCTV if required should be on timber poles. Security lighting (if required) should be minimal,
If security fencing is required, deer fencing with timber posts and wire mesh is least intrusive, followed by dark-coloured steel security fencing. Timber palisade or close-boarded fencing is very visually prominent and should not be used.
Where possible, house transformers within turbine towers to reduce their visibility.
Substation and control buildings should be carefully sited and should generally avoid high or visually exposed locations. If possible, house equipment in existing buildings or screen new buildings with existing or planted native vegetation.
Use recessive colours (such as dark greys and browns) for auxiliary structures. Green is surprisingly difficult to blend into the landscape.
On-site cabling and grid connection cabling should avoid disturbance of sensitive habitat, historic tracks and other historic features. 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.
Consult the Devon Historic Environment Team at an early stage to identify the need for archaeological work and potential mitigation measures through design of auxiliary elements such as site compounds, access tracks, fencing and cable runs.
3.12 Turbine design and finish
To further minimise the landscape and visual impacts of a scheme, the following turbine design factors should also be considered:
- Choose a model of turbine with a balanced proportion of rotor diameter to tower height, avoiding short blades on a tall tower and long blades on a short tower.
- Three bladed turbines tend to look more balanced than two-bladed turbines.
- Tubular steel towers tended to look simpler and less industrial than ‘lattice’ towers.
- Oval turbine nacelles with flowing lines are more aesthetically pleasing than ‘boxy’ shapes
- Simple, pale grey coloured turbines will be most suitable for most turbines over about 25m to tip, to reduce contrast with the sky. However, in some cases darker colours may appropriate for smaller turbines viewed against ground or trees to help them blend into their setting.
- All turbines in a scheme should rotate at the same speed and direction.
- Speed of blade rotations should be kept as low as possible to reduce visual impact.
- Avoid use of advertising on turbines, particularly in rural areas.
- For turbines of 150m and above, explore opportunities to use shields to reduce the visibility of aviation warning lighting when seen from below. Also consider the visual impacts of such lighting, including flicker effects when turbine blades pass in front of it.
- Where appropriate (for example, where schemes are close to populated areas or public rights of way) consider signage to help educate the public about the scheme.
3.13 Guidance on locating single turbines
Single turbines are likely to be located on farms or other rural business sites, or installed as community energy schemes.
Because they are single features they tend to draw the eye, and so it is important that they are designed and sited very carefully.
Select a size of turbine which is appropriate to the scale of the surrounding landscape and nearby buildings.
If a turbine is significantly larger than nearby buildings it will appear taller than it actually is. For example, there may be opportunity to site a smaller single turbine in relation to farm buildings, or larger scale single turbines in relation to larger businesses or community buildings – the wind turbine development should respect the scale of the associated buildings.
Smaller single turbines should usually be located where they are seen in the context of the existing settlement pattern, in order to give the impression of a ‘cluster’ of development.
This also helps to reduce the cumulative effects of numerous individual turbines in the landscape.
3.14 Guidance on locating groups of turbines
Ensure that turbines read as a coherent group in all the main views. Aim for a composition which is visually balanced, simple and consistent as it is viewed from various directions, minimising overlapping of turbines and views of blades only. Where possible:
- seek to avoid ‘stacking’ of turbines when seen from one direction (when they appear one behind the other)
- maintain a clear, balanced cluster of turbines, without outliers which appear remote from the rest of the group
3.15 Minimising cumulative impacts
Cumulative impacts may occur where more than one wind energy development is visible in a view, or where a series of developments occur along a road, footpath or railway line.
They can result from schemes clustering around grid connection points, or suitable access roads.
In extreme cases cumulative impacts can cause a landscape to become dominated by wind turbines to the extent that its character is changed from a farmed landscape to a wind turbine landscape.
The following guidance should assist in minimising cumulative effects.
Ensure that any new wind energy scheme, or the extension or repowering of an existing scheme, takes account of landscape sensitivity, as well as any landscape strategies for wind energy development which may be available.
Ensure the layout and design of development responds to other wind energy developments in the same type of landscape to minimise cumulative effects – this is more important the closer the sites are together.
Consider sequential views from roads and footpaths, so views are not dominated by a continued presence wind turbines along the route.
Where several turbines are seen in the same view, installing turbines of similar design, size and rotation speed helps to reduce the sense of visual ‘clutter’ and distraction.
If wind energy development already exists in a particular type of landscape, further wind energy development should continue this pattern, as long as the existing development is considered appropriate in the context of landscape character.
Ensure multiple developments do not obscure or detract from distinctive landforms or landscape focal points, and are in scale with ridges and hills. It is important to maintain a hierarchy of focal points, so the original valued features can still be appreciated in the landscape.
Locate small turbines close to existing buildings/farms/settlements so they are perceived as part of the existing landscape pattern.
Individual wind turbines should generally appear visually separate from each other unless specifically designed to create the appearance of a single combined wind farm.
Siting turbines on the sides of hills or in valleys, rather than on hill/ridge tops helps to reduce their visibility and therefore lessens cumulative impacts.
Consider views from settlements and protected landscapes, and avoid ‘surrounding’ them with wind turbines.
Undergrounding grid connections reduces the number of visible vertical features and the sense of visual ‘clutter’ in a view.
When considering wind turbine developments, decision-makers should ensure that some key open views devoid of wind turbines are maintained, so that wind energy does not dominate the overall experience of Devon’s landscape.
3.16 Summary checklist
Landscape considerations
Wind turbine schemes are more likely to have an acceptable or less harmful impact on the landscape if they:
- are located outside nationally important landscapes and their settings (although domestic or community-scale schemes may be acceptable depending on the local circumstances, location and scheme design)
- are not located within valued landscapes, or within landcover perceived to be natural such as moorland
- are not detrimental to the intrinsic character or beauty of the countryside
- are proportional to the scale of the surrounding landform;
- respect existing topographical features
- are sited on flat land or shallow slopes rather than steep slopes
- do not harm existing vegetation or protected habitats, and avoid peat soils
- are not detrimental to a sense of remoteness, wildness or tranquillity
- do not damage historic lanes or 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
Wind turbine schemes are more likely to 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
- sited to minimise visibility on skylines
- not detrimental to key views of landmarks or views from popular viewpoints
Design considerations
Wind turbine schemes are more likely to have an acceptable or less harmful impact on the landscape if they:
- incorporate enhancements to biodiversity and habitat connectivity
- have ancillary buildings and structures painted a recessive colour (preferably olive green, brown or dark grey)
- have fencing, gates, CCTV poles, surfacing etc. which use natural materials as much as possible and are as unobtrusive as possible
- do not introduce urbanising features such as black top tarmac or concrete kerbs into rural locations
- minimise light pollution
Cumulative impacts
Wind turbine schemes are more likely to have an acceptable or less harmful impact on the landscape if they do not have unacceptable cumulative impacts with other existing, consented or planned renewable energy schemes.