site suitability study for wind farm development in scarborough, north yorkshire

IDENTIFYING THE MOST SUITABLE SITE

FOR A WIND FARM DEVELOPMENT NEAR

SCARBOROUGH, NORTH YORKSHIRE

Mark Gadogbe

May 2014

INTRODUCTION

Wind energy is seeing increasing developments in recent years. Irrespective of this trend, wind

farms cannot be cited at just anywhere. There is the need for locating suitable sites even among

potential sites as many factors including bio-physical, environmental, social, financial and legal

often place a limit on wind farm development. Physical factors may include the nature of the

wind resource at the potential site and the nature of the terrain. Often, social factors include

visual impact of the development on the public, turbine noise levels and closeness or otherwise

of the farm to residential and conservation areas. Many legal requirements also need to be

satisfied in order to receive planning permission for the development. Obtaining local planning

authority permission is thus increasingly becoming difficult as many criteria need to be met and

properly evaluated. As part of planning application for a wind farm development, an

Environmental Impact Assessment (EIA) is required, and which should identify any possible

impacts (positive and negative) associated with the proposed development considering all

statutory requirements and how possible negative impacts may be mitigated. It helps to

determine whether to move forward with an action or proposal (UNDP, 2011). The Borough of

Scarborough is believed to hold good potential for commercial wind farm developments due to

its strategic location and also on the basis of the growing number of wind farm developments

close to the Borough such as the Lissett Airfield wind farm, located south of Bridlington in East

Riding of Yorkshire. The aim of this project is thus to use the industry standard software

WindPRO to undertake a simple EIA of two potential wind farm locations within the Borough of

Scarborough out of 18 identified potential wind farm sites and determine which of the two sites

has the least potential environmental impact and thus most likely to receive planning permission.

DESCRIPTION OF SELECTED WIND FARM SITES

Figure 1 shows the map of the 18 identified wind farm sites around Scarborough and figure 2,

the wind resource potential map.

Wind farm sites 5 and 17 were selected for evaluation.

Figure 1: The 18 identified potential wind farm sites around Scarborough.

Figure 2: Wind resource map (80m a.g.l) of the potential wind farm sites.

Wind farm 5 (WF5)

WF5 is the smaller of the two and the site boundary covers an area of 0.119km2. WF5 is located

in the low lying area of the Vale of Pickering with average wind potential between 7 – 7.8m/s.

This is quite a low wind resource; nevertheless, it is adequate for commercial wind power

production. The site has an average elevation of about 30m above sea level. There are farmlands

and a few plantations located outside of the wind farm boundary with the Pitts plantation sharing

boundary with WF5 on the south-western end. A surface water line runs almost through the

middle of the site. There is a road network both to the west (about 570m from west boundary)

and east (about 600m), with a major road (A170) about 700metres measuring in north-west

direction. The main residential dwelling (cluster of buildings) is located north-west about 650m

from the site’s boundary. The centre point of the site has British TM grid reference 496994,

482520. The closest public amenity is about 800m NW from site boundary. The closest isolated

residential building is a lodge 730m from turbine position on farm.

Wind farm 17 (WF17)

WF17 covers an area of 0.333km2 and is located along the North Yorkshire Coast, south of Filey

on the border between the TA and East Riding of Yorkshire. The location puts it in a high wind

resource zone; however, wind speed is variable over the entire site with some portions having

wind speeds in between 7.8 – 8.5m/s, other portions within 8.5 – 9.3m/s range and the greater

proportion with high speeds of 9.3 – 10.7m/s (figure 2). Only a small portion of the farm is

onshore, thus the site’s centre point is offshore with British TM grid reference 5111403, 482443.

The onshore portion is however characterised by cliffs and some farmlands and woodlands are

located outside of the farm boundary, with the closest woodland being the North Cliff country

park to the south-west. The site has average elevation of about 54m above sea level. The closest

major road (A1039) runs on the south about 1300m from the site boundary. A little south-east

about 640m from the site boundary is the main residential dwelling (cluster of buildings). The

closest public amenity is about 1100m from the closet turbine. No surface water line runs

through the field but many are very close by. There is an SSSI close to WF17 on its eastern

boundary side. The SSSI boundary is about 420m from WF17 boundary and about 670m from

the position of the nearest turbine. Another SSI is located to the west about 1.8km away.

TURBINE SELECTION

The Vestas V90-3.0MW turbine was the turbine of choice for installation at both sites. The

turbine’s characteristics include a tubular tower, three bladed with an overall height to blade tip

of 125m. This turbine has been selected following a careful examination of the sites and it is

believed this turbine will help maximise the wind energy resource of the proposed wind farm

sites. Technical details are shown in figure 3. Only one turbine was considered for WF5 due to

its small size (figure 4). WF17 has installed two wind turbines as the size of the farm could

accommodate the two (figure 5). A south-westerly prevailing wind condition was considered for

both sites but with an additional north-easterly on-shore wind component for WF17 due to its

closeness to the coast. The development on both sites would be grid connected and would require

on-site access track, sub-station, a network of buried cables as well as other related engineering

works. The expected operational life of both developments is 25years.

Figure 3: Technical data of turbine. Source: Vestas (2009).

Figure 4: Turbine location on WF5.

Figure 5: Turbine location on WF17 and location of SSSI (in red).

PLANNING POLICY CONTEXT OF THE WIND FARM DEVELOPMENT

This section describes relevant aspects of national and local renewable energy (RE) and planning

policies and guidance which the potential wind farm developments are expected to operate by

and try to satisfy.

Firstly, the need for the wind farm development is in agreement with UK Government’s climate

change and RE policy objectives of producing a proportion of its electricity from effective RE

technologies. Both onshore and offshore wind farm developments are highly encouraged and

promoted because of the government’s policy objective of obtaining at least 20% of EU’s energy

from renewable sources by 2020, with this target shared among each EU member state.

Reference is made to some specific policy documents such as the UK Renewable Energy

Strategy (2009), Climate Change Act (2008), Wildlife and Countryside Act 1981 (as amended),

UK Biodiversity Action Plan (1994), etc. The PPS22 Renewable Energy policy guideline also

establishes the need for RE projects to be environmentally sustainable as well as socially and

economically sustainable. As such it proposes that the overall environmental and socio-economic

relevance of all renewable energy project proposals be significantly weighed and assessed

(without giving in to making of unfounded assumptions) in event of granting planning

permission. At the local level, planning authorities are to set out the criteria that will be applied

in assessing applications for planning permission for RE projects (ODPM, 2004). The selected

wind farm sites are located in an area administered by the North Yorkshire Local Authority and

as such the development will be in accordance with their statutory development plans and

policies. WF5 will have a 3MW capacity and WF17 a 6MW capacity and as such will not be

regarded as “major” developments. With capacities not exceeding 50MW thus, assessment with

regards to Section 32 of the Town and Country Planning Act (1990) is required as stipulated in

the companion guide to PPS22 (ODPM, 2004). Also, planned as grid-connected developments,

requisite applications for grid connection permission will be made with regards to Section 37 of

the Electricity Act (1989). The Department of Trade and Industry’s publication 'The Assessment

and Rating of Noise from Wind Farms' (ETSU, 1996) will be used as standard guide in assessing

noise impact of the developments.

LANDSCAPE AND VISUAL IMPACT ASSESSMENT PLUS PHOTOMONTAGE

Landscape and visual effects of wind farm developments are required to be assessed on a case-

by-case basis (ODPM, 2004). Landscape impacts often arise from significant changes to the

landform or land use. Suitable terrain topography is an essential factor of consideration in the

suitability of a site for wind farm development irrespective of the presence of a good wind

regime. The terrain must enhance visibility of the turbines to capture wind, construction and

engineering works and not pose much difficulty in terms of access to site. WF17 location on the

cliffs and the coast is expected to present more difficult landscape issues than WF5.

A blade tip ZVI assessment was performed for both wind farms and shows areas of the landscape

from where any portion of the turbines are visible. The calculation however assumes presence of

no obstacles on the landscape. For both farms, turbines are visible from a large portion of the

landscape (figure 6 and 7). For WF5, the ZVI calculation showed that for 1634 hectares of

calculation area, the turbine is visible from about 99.6% of the area. Similarly for WF17, the

turbines are visible from about 70% of a calculation area of 2240hectares. Thus for both farms,

turbines are clearly visible from many locations including residential areas and transport routes.

Community consultations will thus be required in fully assessing the general attitude of residents

regarding turbine visibility. Full ZVI reports are attached (appendix 1 and 2).

Figure 6: ZVI map for WF5 showing only small non-visible (blue) areas.

Figure 7: ZVI map for WF17 showing only small non-visible (blue) areas.

Figure 8 shows photomontage of the single wind turbine on WF5 landscape. Photomontage

assessment was not possible for WF17 as turbines were not visible on Google map. This is partly

due to the cliff-like nature of the terrain, thus possibly hiding the turbines or possibly due to the

area not being very accessible.

Figure 8: Photomontage of turbine on WF5 using Google map.

NOISE IMPACT ASSESSMENT

This section identifies potential impacts in relation to turbine noise. Noise impact is an important

consideration in wind farm development as wind turbines often generate noise when in operation

with noise levels varying with wind speed. Noise levels from turbines are however generally

low, often masked by wind-generated background noises (PPS22, 2004).

Often, noise impacts depend on wind farm location and its distance relative to residential or built

areas. Usually a 750m or more separation distance between turbine and nearby dwellings is

required to get noise and shadow impacts at an acceptable level.

Acceptance is established by comparing noise levels produced by the combined operation of

turbines with appropriate noise limits at nearby residential properties (ETSU, 1996). Impact on

nearest dwellings was assessed and calculation employed 90% exceedance values (L90)

designed in compliance with ETSU-R-97 limits. Full reports are attached (appendix 3 and 4).

WF5 satisfied the requirements on turbine noise at all wind speeds considered and the impact on

both nearest isolated dwelling and cluster of buildings is considered acceptable (figure 9).

Maximum noise level from the turbine was 37.7dB at 8m/s. However, the distance requirement

was not satisfied. There is enough space to reposition turbine as mitigation and thus satisfy both

noise and distance limits. For WF17 noise and distance limits were satisfied with regard to the

only isolated building close to the farm but with regard to the impact on the larger residential

buildings, noise was satisfied but distance failed (figure 10). This may be because looking at the

location of the cluster of buildings relative to the first turbine, they appear closer than the

isolated building which also is closer to second turbine than cluster of buildings. Maximum noise

level was higher (39.8dB at 8m/s). There is however little onshore space to reposition turbine to

satisfy limits. Meanwhile, the settlement density around WF17 is also greater than WF5.

Figure 9: Noise impact map for WF5: nearest isolated building and cluster of buildings.

Figure 10: Noise impact map for WF5: nearest isolated building and cluster of buildings

SHADOW FLICKER ASSESSMENT

The shadow of moving wind turbine blades can create strobe effects with respect to nearby

houses (UNDP, 2011). Shadow flicker impacts are often a function of factors such as distance of

residences from wind turbine, sun position, window sizes and the orientation, frequency and

duration of the flicker. Shadow impact map for both farms is shown in figure 11 and 12 and the

statistics for both farms highlighted in table 1. Full report is attached as appendix 5 and 6.

Table 1: Shadow flicker statistics

Wind farm Shadow hours per year

(h/year)

Shadow days per year

(days/year)

Max shadow hours

per day (h/day)

WF5 13:34 38 0:28

WF17 37:02 97 0:29

The table shows better shadow flicker impact for WF5 than WF17. With regards to the cluster of

buildings however, more buildings around WF5 may experience shadow effects from the farm

than for WF17. In mitigating the effects however, turbines will only need shutting down for

about an hour on days flicker is expected to occur. Both farms will cast some shadows on small

portions of the road network which could affect road users.

Figure 11: Shadow flicker map for WF5

Figure 12: Shadow flicker map for WF5.

ECOLOGY AND ORNITHOLOGY IMPACT

Wind farm developments are expected to consider impacts on flora, fauna and habitats such as

conservation areas that are under legal protection according to legislations such as the Wildlife

and Countryside Act 1981. Both wind farms would present low ecological consequences as no

long term long-term impacts on the integrity of the areas are expected. However, the closeness of

WF17 to an SSSI could pose some challenges.

ACCESS, TRAFFIC, TRANSPORT AND GRID CONNECTION IMPACT

It is important that wind farm sites be adequately served by roads that are wide enough to ensure

transport of turbine components to site. However, turbines are also not required to be too close to

road and utility networks; often they are expected to be a “fall over distance” away. The “fall

over distance” is taken to be the height of the turbine to the tip of the blade, plus 10% (ODPM,

2004).

Increased traffic levels are anticipated following both wind farm constructions; however, levels

are anticipated to be higher for WF5 due to its closeness to the road network. Traffic situation

will thus need monitoring and operations timed to minimise impact on local transport. In terms

of accessibility, WF5 easy terrain conditions and closeness to road network will make it more

accessible. Considering the location of both wind farms in relation to road networks and on the

assumption that national grids will most possibly be close to road networks, grid connection is

expected to be easier and present limited impact for WF5 than for WF17. This is partly because

WF17 is far from road network and characterised by a more difficult cliff-like terrain than WF5,

thus longer power cables and more ground works will be required in connecting WF17 to the

grid which also will increase development costs. Other environmental impacts from grid

connection works will mostly be landscape, visual and noise related.

SOCIOECONOMIC IMPACT

Little negative socioeconomic impacts are anticipated for both developments. Rather, direct and

indirect employment opportunities, benefits through land rents or purchase and potential benefits

through social responsibility requirements expected of wind farm developers are expected.

WIND ENERGY RESOURCE ASSESSMENT

The full energy reports for WF5 and WF17 are attached as appendix 7 and 8 respectively.

Annually, the single turbine on WF5 is estimated to generate electrical energy equivalent to

8502.6MWh/yr at 7.9m/s mean wind speed at hub height and 2834 full load hours per year. This

is after accounting for a 10% loss in energy to cater for turbine inefficiency factors such as drag

and tip loses, wake effects and general turbine malfunctions. Based on UK average typical high

electricity consumption of 5100kWh/yr (Ofgem, 2011), this windfarm should be able to meet the

demands of over 1500 houses. For WF17, annual generation for the two turbines after accounting

for 10% loss in energy is 20,069.2MWh/yr (10,021MWh/yr and 10,048MW/yr respectively) at

8.6m/s mean wind speed at hub height and 3345 full load hours per year. Energy demand of over

3500 houses should be met from generation from this wind farm. At higher wind speed, more

energy is expected to be generated hence the higher generation per turbine for WF17. The

directional analysis shows the impact of hills and obstacles on overall energy generation and that

for both farms more energy was generated in WSW sector (figure 13 and 14). There was some

array loses for WF17 but none for WF5 because WF5 has only a single turbine installed.

Figure 13: Directional analysis of energy production for WF5

Figure 14: Directional analysis of energy production for WF17

OVERALL ENVIRONMENTAL SENSITIVITY

There are no international or national landscape designations such as Ramsar sites, Special

Protections Areas (SPA), Special Sites of Scientific Interest (SSSI) and Special Areas of

Conservation (SAC) within boundaries of both sites. While none is found in close proximity to

WF5, WF17 has an SSSI in close proximity. No designated migratory birds’ flight paths were

found located either within or in close proximity to both sites, thus, it is not anticipated that the

development on both sites will present significant negative ornithological impacts or negatively

impact wildlife. However, the closeness of WF17 to an SSSI makes it a more sensitive site

because areas such as SSSIs, SPAs and SACs are important for instance to a variety of bird

species protected under EU and UK legislations. This places a constraint on developing the site

as it implies the need for very careful balance between renewable energy generation and

conserving the environmental sensitive area.

There are no rights of way on both sites. No military establishments, airports or any other radar-

using establishments were found within both sites or within the 15km radius of the proposed

wind farms as suggested in PPS-22 (ODPM, 2004). There also are no Scheduled Monuments or

Listed Buildings present within both wind farm boundaries. Also, no residential properties are

within both wind farm boundaries but are outside of site boundaries and an assessment of these

properties in relation to potential noise impacts and shadow flicker as presented in the noise and

shadow flicker section showed WF5 performing quite better in general. WF5 appears more

accessible than WF17 due to its location, terrain characteristics and closeness to road network. In

respect of WF17 being close to the sea, foreshore and marked tidal boundary, the turbines could

potentially be at risk of high tides and storm surges and possible impact of extremely strong wind

currents. Though high wind conditions are good for wind farm development, extremely high

winds are often problematic.

CONCLUSION

The anticipated impacts of both wind farm development have been evaluated. Both

developments are characterised by positive environmental effects relating to carbon emission

reduction and will contribute to the UK Government’s renewable energy targets. Few significant

environmental impacts are expected from both wind farm developments with potential for most

to be reduced or mitigated.

However, overall assessment reveals that the WF5 site scores better for wind farm suitability and

less environmental impacts and thus will be higher placed in receiving planning permission.

Though a small capacity development however, the PPS22 directs that planning authorities

should not reject planning applications simply because the level of output for a development is

small (ODPM, 2004).

This assessment is however purely desk-based as such more detailed analysis involving field

visits and consultation with major stakeholders including resident communities will be prudent.

REFERENCES

ETSU. 1996. The Assessment and Rating of Noise from Wind Farms. The Working Group on

Noise from Wind Turbines. ETSU Report for the DTI, ETSU-R-97.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/49869/ETSU_Full

_copy__Searchable_.pdf. Accessed: 13/05/14.

ODPM. 2004. Planning for Renewable Energy - A Companion Guide to PPS22. 1-186.

Ofgem. 2011. Typical domestic energy consumption figures. Factsheet 96.

https://www.ofgem.gov.uk/ofgem-publications/64026/domestic-energy-consump-fig-fs.pdf.

Accessed: 18/05/14.

UNDP. 2011. Environmental Impact Assessment for Wind Farm Developments: A Guideline

Report. 1-73. http://www.cedro-undp.org/documents/mfiles_data/EIA.pdf. Accessed: 14/05/14.

Vestas. 2009. V90-3.0MW: Exceptional performance and reliability at high-wind-speed sites.

http://www.vestas.com/Files/Filer/EN/Brochures/Vestas_V_90-3MW-11-2009-EN.pdf.

Accessed: 20/05/14.