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Strategic Initiative to Introduce Commercial Land
Based Wind Energy Development to the Western Cape
TTOOWWAARRDDSS AA RREEGGIIOONNAALL MMEETTHHOODDOOLLOOGGYY FFOORR WWIINNDD EENNEERRGGYY SSIITTEE SSEELLEECCTTIIOONN
REPORT 2: METHODOLOGY 1 : CRITERIA BASED ASSESSMENT
MAY 2006
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Strategic Initiative to Introduce Commercial Land
Based Wind Energy Development to the Western Cape
TTOOWWAARRDDSS AA RREEGGIIOONNAALL MMEETTHHOODDOOLLOOGGYY FFOORR WWIINNDD EENNEERRGGYY SSIITTEE SSEELLEECCTTIIOONN
REPORT 2: METHODOLOGY 1 : CRITERIA BASED ASSESSMENT
prepared for
Provincial Government of the Western Cape 1 Dorp Street, Cape Town, 8000
Tel: +2721 483-3185 Fax: +2721 483-4373
by
CNdV africa planning & design environmental planning, landscape architecture, urban design
72 Barrack Street, Cape Town, 8000 Tel: +2721 461-6302 Fax: +2721 461-6466
Email: [email protected]
MAY 2006
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The use of criteria-based policies is an essential part of the approach established under PPS22. It is likely that at the regional level there will be two broad types of policy: one type would be associated with sub-regional targets and the identification of broad areas, the second with development criteria to assist in implementing the regional strategy.
source: PPS 22 Planning Policy Statement 22: Renewable Energy : Office of the Deputy Prime Minister, United Kingdom
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OVERALL STRUCTURE OF REPORTS LIST OF REPORTS
Report 1 Executive Summary and Synthesis Report
Report 2 Report on Methodology 1 (Criteria Based Assessment) (this report) Report 3 Report on Methodology 2 (Landscape Assessment)
Report 4 Comparative Assessment of Methodologies 1 & 2
Report 5 Proposed Regional Methodology
Report 6 Proposed Site Level Methodology
Report 7 Annexure Reports
1. The Brief
2. Overseas Study Report
3. GIS / Software Report
4. Towards a Provincial Policy Framework for Wind Energy Development
5. References
CONTENTS : REPORT 2: METHODOLOGY 1
1. INTRODUCTION
1.1 Report Structure
1.2 Purpose
1.3 Scope
1.4 Evaluating Methodology 1
2. CRITERIA DESCRIPTION
2.1 Noise
2.2 Shadow flicker
2.3 Wind farm layout
2.4 Wind farm spacing and turbine size
2.5 Urban areas and residential areas
2.6 Transportation routes
2.7 Infrastructure / Transmission Lines
2.8 Defence Constraints
2.9 Aviation Constraints
2.10 Nature reserves
2.11 Protected areas
2.12 Scenic routes
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2.13 Coast and Rivers
2.14 Wetlands
2.15 Species and vegetation protection
2.16 Topography
2.17 Heritage sites
3. GROUPING AND MAPPING OF CRITERIA
3.1 Not Mapped
3.2 Grouping of Criteria
3.3 Basic Methodology
3.4 Criteria Thresholds
3.5 Data Representation
3.6 Database and GIS
4. OUTPUT AND ANALYSIS
4.1 Individual Criteria and Mapped Layers
4.2 Spatial Output
4.3 Summary of Output
5. REVISED OUTPUT
5.1 Ranking of Criteria
5.2 Scoring of Criteria
5.3 Revised Output Map
6. CONCLUSIONS: METHODOLOGY 1
LIST OF APPENDICES TO REPORT 2 Appendix A Spatial Output Maps per Criteria
Appendix B Report on GIS Data Sources and Availability
Appendix C Alternative Output Maps
LIST OF FIGURES Figure 1: Project and Report Structure
Figure 2: Methodology 1 – Process
LIST OF MAPS Map 1: Infrastructure Criteria
Map 2: Environmental & Planning Criteria
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Map 3: Composite - All Criteria
Map 4: Available Land
Map 5: Revised (Ranked) Output Map
LIST OF TABLES Table 1: Thresholds for Selected Criteria used in Methodology 1
Table 2: Suggested Ranking of Criteria
ABBREVIATIONS / GLOSSARY CSIR Formerly the Council for Scientific and Industrial Research)
DEA&DP Department of Environmental Affairs and Development Planning, Provincial Government of the Western Cape
DEAT Department of Environmental Affairs and Tourism
DME Department of Minerals and Energy
DWAF Department of Water Affairs and Forestry
ENPAT An Environmental Information Database operated by DEAT
GIS Geographic Information System
MW Megawatt (1000 kilowatts)
NBI National Botanical Institute
NEMA National Environmental Management Act
PGWC Provincial Government of the Western Cape
RSA Republic of South Africa
WE Wind Energy
WT's Wind Turbines
ACKNOWLEDGEMENTS This report was produced by Derek Chittenden, Ebrahim Daniels, Soraya Sabera and Reinhold Viljoen of CNdV Africa under the guidance of a Provincial Task Team comprising Paul Hardcastle, Ayub Mohamed and Raudhiyah Waggie. The input of the project Reference Group to the project is acknowledged with thanks. Refer to Appendix C of Report 1. The authors also wish to thank those organisations and individuals throughout the world that provided valuable advice and guidance to this work.
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1. INTRODUCTION 1.1 Report Structure This report forms part of a series of specialist assessment reports that are interrelated and should be read together. The reports are part of a Department of Environmental Affairs & Development Planning (DEA&DP) of the Provincial Government of the Western Cape (PGWC) project entitled “Strategic Initiative to Introduce Commercial Land Based Wind Energy Developments to the Cape West Coast”.
Figure 1: Project and Report Structure Report 1 is a Summary Report, which provides an overview of the work carried out and
sets out the major conclusions, namely the recommendations related to a regional method to assess landscapes for wind energy development.
Report 2 sets out Methodology 1. This is a criteria-based method for determining the
suitability of specific areas for wind energy developments at a regional level. Report 3 sets out Methodology 2. This is a landscape-based assessment method for
determining the suitability of specific areas for wind energy developments at a regional level.
Report 4 contains a comparative assessment of the differences, strengths and
weaknesses between Methodologies 1 and 2. Report 5 recommends the proposed regional landscape assessment method which
combines aspects of Method 2 (landscape assessment) with Method 1 (criteria based) as the foundation method.
Report 6 sets out the recommended project level assessment method.
Report 7 contains separate Annexures including a comprehensive report on the overseas study tour carried out by DEA&DP officials and the consultants, and a report on the GIS/ software investigation carried prior to and during the study.
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1.2 Purpose This report focuses on developing and testing a criteria-based method for determining, at a regional level, the suitability of specific areas for wind energy developments. It is a regional decision-making tool where the goal is determining an appropriate methodology, in the South African context, for wind farm location. This method (termed “Methodology 1” in this report) was developed by DEA&DP and is derived from a comparative assessment of international practice relating to criteria and thresholds applied to wind energy developments1. Key aspects of the methodology are: ● It has been developed in the knowledge that wind turbines will become a feature of the
landscape in the Western Cape ● It is predicated on the need for a low-cost and effective assessment method for the
Province and South Africa ● The methodology is to be tested against a landscape assessment method ● The overall approach is the spatial identification of two generic zones for wind energy
development – namely inclusion zones where wind energy developments may be permitted and exclusion zones where they will not be permitted, this is accomplished by creating setbacks ("negative buffers") for a list of criteria to establish exclusionary areas.
● The criteria were chosen after an exhaustive investigation of international literature and
personal contact with various international roleplayers, including governmental organisations, wind energy associations and developers. (Refer to Reference 1, and Overseas Study Report: Annexure 2).
1.3 Scope The scope of the development of Method 1 has been partly constrained by the practicalities relating to the acquisition and manipulation of large spatial datasets. A considerable amount of time was spent at the outset of the project in evaluating several alternative computer programmes that could manipulate both 2 dimensional and 3 dimensional information and could effectively express these criteria on maps. A brief report is contained in Annexure 3 on the GIS software investigation appendix B to this report provides a brief commentary on the lack of or unavailability of certain datasets which also limited the scope of the output. 1.4 Evaluating Methodology 1 This document sets out the results of the evaluation of Methodology 1. The evaluation was conducted in three phases for the study area as defined.
1. Original criteria set and thresholds supplied by DEA&DP were assessed and finalized, primarily based on the results of the overseas trip.
2. Evaluation using final criteria sets and recommended thresholds 3. Evaluation using additional criteria / ranking of criteria
1 (Reference 1 in Annexure 4) (Strategic Initiative to Introduce Commercial Land Based Wind Energy Developments to the Cape West Coast, Draft Document, PGWC, 2005)
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2. CRITERIA DESCRIPTION The background information document prepared by DEA&DP (Reference 1) listed a number of criteria that are to be considered when determining suitable locations for WE development. Each criterion that has application in wind turbine location is briefly described below (not in any specific order). Please also refer to Annexure 2: Report on Overseas Study Tour, which provides more detailed comment and evaluation of the various criteria listed below). 2.1 Noise This is the noise produced by the turbine generator and associated mechanicals and by the sweep of the blades. Due to the advancement of technology and design the low levels of noise produced by modern wind turbines suggest that the criteria threshold levels will not be reached. Turbine noise levels in relation to ambient noise levels are also unlikely to be applicable as increasing ground level wind noise tends to drown blade noise. (The noise criteria is therefore subsumed in other setbacks (residential areas and homesteads etc.) 2.2 Shadow flicker This is the flicker of the sun through the turbine blades. Shadow flicker can be defined spatially but with some difficulty as sun angles, climate, and viewpoints determine the presence, duration and level of flicker. Due to this analytical difficulty, and as the area affected is generally small, shadow flicker is subsumed in other criteria in this report. 2.3 Windfarm Layout The size and layout of a wind farm can have a significant influence on visual and aesthetic impact. Large wind farms have a potential greater cumulative impact on the landscape, depending on their location. However smaller wind farms or individual turbines scattered throughout a landscape are likely to have greater cumulative impact. Turbine layout in turn influences visual appeal as regular spacing and regular hub heights may be less intrusive than irregular layouts. 2.4 Windfarm Spacing and Turbine Size This criteria group is directly related to cumulative impact. Wind farm spacing influences the total number of turbines that may be visible at any time. More than one wind farm in the field of view adds to the visual impact. Turbine size has a direct influence on the landscape as tower and total blade height dictate the lines of sight to the turbine and hence the zone in which it is visible. 2.5 Urban Areas and Residential Areas Urban and residential areas house large populations that may be influenced by wind farms visually, audibly and in terms of safety. As identified in the Summary Report (Report 1) the prevailing policy internationally has been to reduce the visual impact of wind farms on urban populations in preference for rural locations, where population numbers affected are lower. However, recent policy shifts internationally are for urban "brownfield" sites.
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2.6 Transportation Routes These routes carry people through areas where wind farms are visible to varying degrees including roads, rail or other routes such as hiking trails. The nature of the route, (especially whether it has a scenic or tourism value) its relative importance (national, provincial, district or local) its carrying capacity and the topography all influence the impact of wind farms on visual experience. (See 2.12) 2.7 Infrastructure / Transmission Lines Power and gas lines and beacons relate to wind farms mainly through safety considerations. Power line pylons and beacon towers are however also significant vertical elements in the landscape. 2.8 Defence Constraints Areas in this category have special requirements that relate to security. Areas of national importance in terms of defence require undeveloped areas around them to maintain high levels of security or, in the case of nuclear facilities, to ensure resident populations are low. 2.9 Aviation Constraints Wind farms influence aviation both directly and indirectly. The operation of radar and the height of overflying are influenced by the proximity of wind turbines. In the case of primary radar, wind turbines clutter the signal and hence a significant buffer around these installations is required. 2.10 Nature Reserves These reserves provide both sanctuary of habitat for animal and vegetative species and amenity for visitors. Wind farms mainly influence the ‘naturalness’ of these areas, as they insert a technological element into the landscape. 2.11 Protected Areas These areas are protected due to environmental, environmental or scenic beauty reasons and may include heritage sites or valuable landscapes. Wind farms influence these areas in the same way as nature reserves. In the case of extensive areas, such as mountain catchments, the environmental influence may be negligible. 2.12 Scenic Routes Routes are classified as scenic due to the natural beauty and interest of the surrounding landscapes. This criterion is thus directly linked to landscape assessment. Scenic routes are classified in this report as of major or minor tourist importance. 2.13 Coast and Rivers Both coast and rivers are special habitats and places of recreation and are linear elements in the landscape. Onshore wind turbines close to the coast may have a significant influence on
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the amenity of beaches, coastal areas and rivers that are in close proximity. These areas also house avian species that require protection. 2.14 Wetlands These areas range from large wetlands of significant international importance to small local water bodies. The former have both conservation and scenic value while the latter house water birds and other species. The proximity of wind turbines to any wetland is primarily of concern with regard to impact on birds. 2.15 Species and Vegetation Protection Avian species in particular have habitats that are potentially influenced by wind turbines. Wind turbine blades are responsible for ‘bird strikes’ while the footprint of towers, roads and associated structures disturbs vegetation. 2.16 Topography The visual influence of wind turbines is significantly influenced by topography. Wind turbines may be fully or partially hidden by hills and mountains. Conversely their visibility is increased when positioned on ridgelines and hilltops. 2.17 Heritage Sites These are sites of historical and cultural value either with national or provincial designations, and can range from heritage landscapes to individual buildings. The list of criteria briefly described above have both regional and local implications, as well as differences in their influence; either predominantly visual, of safety nature, or of a conservation/environmental nature. The thresholds applied to the criteria, for the purpose of mapping 'exclusion zones' are described in the following section.
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3. GROUPING AND MAPPING OF CRITERIA 3.1 Not Mapped Some of the criteria described above either cannot be mapped or were subsumed by other criteria thresholds. These include: ● Noise ● Shadow Flicker ● Wind farm layout / distance between turbines ● Gas transmission lines
3.2 Grouping of Criteria The criteria were essentially grouped into two main categories for purposes of the mapping exercise; these are: ● Environmental and planning related criteria ● Infrastructural criteria
3.3 Basic Methodology Figure 2 overleaf illustrates the process followed in Methodology 1. The method has been largely based on international precedent involving "negative" mapping of criteria "buffers". In simple terms, the process was broadly as follows: ● Firstly, the GIS framework was developed. This included an extensive data collection and
collation process. ● Secondly, all data was compiled, ensuring as far as possible that consistent data was
used, and that it was captured in a way that allowed manipulation and enlargement to a reasonable scale (1:50 000).
● Thirdly, a preliminary analysis of the criteria was carried out, leading to criteria evaluation and final selection of thresholds to be tested.
The GIS report in Appendix B should be referred to for more detail on the data sets (source and availability). Annexure 3 to the main report describes the software analysis and computer aided methods of data analysis which were achieved via the GIS Arc View platform. 3.4 Criteria Thresholds The original criteria thresholds (as produced in Table 7 of the PAWC document: Ref. 1) were critically assessed and revised in the light of the preliminary analysis and experience from the overseas trip (See Report on Wind Energy Study Tour, Annexure 2). The revised thresholds are indicated in Table 1, which also illustrates the grouping of each criteria into either environmental and planning concerns, or infrastructural concerns, as well as attempting to distinguish between visual, conservation or safety concerns. 3.5 Data Representation
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All maps are represented in this report at A4 scale for convenience. At this scale (1:550 000) the maps can only give an impression of the extent of coverage, and does not illustrate the wealth of data often behind each layer. The detailed data has been provided in a separate CD to the client. 3.6 Database and GIS The database developed for use in the criteria-based method (Method 1) has the following attributes, which also apply to the landscape assessment method (Method 2).
1. It is rigorous and organized as a GIS – permitting authoritative results 2. It is accessible, using standard software (Arc View) for data input 3. It is expandable and additional layers can be added at any time 4. The data is as up-to-date as possible
The GIS layers used in this report are derived from a number of sources, which are elaborated in Appendix B.
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Figure 2: Methodology 1 - Process
OVERLAY : OUTPUT 1
ASSESSMENT
SYNTHESIS (A) SYNTHESIS (B)
CRITERIA EVALUATION AND SELECTION
PRELIMINARY ANALYSIS
GIS FRAMEWORK / DATA COLLECTION
DATA COMPILATION
A9
A8
A7
A6
A5
A4
A3
A2
A1 MAP SETS (A) ENVIRONMENTAL / PLANNING
LAYERS
1. Coastline
2. Wetlands
3. Rivers
4. Reserves / Protected areas
5. RAMSAR Sites
6. Protected Bird Areas
7. Heritage Sites
8. Scenic Routes (major)
9. Scenic Routes (local)
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1MAP SETS (B)
INFRASTRUCTURE LAYERS
1. Urban edges
2. Urban areas
3. Residential
4. Security Sites
5. Major airports
6. Local airfields
7. Radio beacons
8. Communication towers
9. National roads
10. Local roads
11. Rail lines
12. Powerlines
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Table 1: Thresholds for Selected Criteria used in Methodology 1
Grouping Key Concern
Group No.
Subset No.
Criteria (Distance from)
Threshold Value
Notes/Data Source [See Note (1)]
Environmen
tal Planning
Infrastructural
Visual
Conservatio
n Safety
1. Urban Areas 800m from urban edge
Urban edge lines assumed where necessary. This distance adequately covers noise and flicker criteria
2. Residential Areas (including rural dwellings)
400m
Threshold adequately covers noise and flicker criteria. All rural dwellings mapped at 1:50 000 series, but these are not comprehensive
3. Transport Routes 3a. National Roads 3km Should depend on scenic value of route. Can be reduced.
3b. Local Roads 500m Review if high scenic value. 3c. Provincial Tourist Route 4km Statutory scenic drives 3d. Local Tourist Route 2,5km Assumption made for local importance. Safety consideration.
3e. Railway Lines
250m
No distinction drawn between passenger and goods lines. Also, rail corridors usually visually disturbed
4. Transmission Lines 4a. Major Power Lines 250m Excludes gas lines 4b. Cell Phone Masts +
Communication Towers
500m No data available/provided. (Not mapped)
4c. Radio + Navigation Beacons 250m Digitised from aeronautical maps 5. Key Infrastructure/Airports 5a. Airport with Primary Radar
25km Previous threshold of 15km increased. To be confirmed with agency at regional level.
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Table 1 (Continued): Thresholds for Selected Criteria used in Methodology 1
Grouping Key Concern
Group
No.
Subset No.
Criteria (Distance From)
Threshold Value
Notes/Data Source [See Note (1)]
Environmental
Planning
Infrastructural
Visual
Conservation
Safety
5b. Local Airfield 2,5km
Previous threshold of 15km reduced. To be confirmed with agency.
5c. National Security Sites (e.g. Koeberg) 15km
To be reduced to 5km. To be discussed with agency concerned
6. National Parks + Provincial Nature Reserves 2km
Increased from 1km international standard
7. Protected Areas 7a. Mountain Catchments 500m Not mapped. 7b. Protected Natural Environment 2km As per statutory protection 7c. Private Nature Reserves 500m Data not consistently available (not mapped)
8. Coast & Rivers 8a. Distance to Coastlines of
Undisturbed Scenic Value
4km (see Note 2)
8b. Distance to Rivers 500m Only perennial rivers used 8c. Distance to 1:100 Year Floodline 200m Not mapped 9. Sensitive Areas (Avian) 9a. Distance to Major Wetlands
(Ramsar Sites)
2km Increased from 1km. Assumed to increase bird safety.
9b. Distance to Local Wetlands 500m Increased from 300m to ensure bird safety.
9c. Distance to Bird Habitats or Avian Flight Paths where known 1km
Increased from 500m. Assumed specific breeding sites dealt with at EIA level.
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Table 1 (Continued): Thresholds for Selected Criteria used in Methodology 1
Grouping Key Concern
Group No.
Subset No.
Criteria (Distance From)
Threshold Value
Notes/Data Source [See Note (1)]
Environme
ntal Planning
Infrastructural
Visual
Conservati
on
Safety
10. Topographical 10.a Maximum Height above Local
Topography 25m Note 3
10b. Distance from Ridge Lines 500m Ridge lines plotted manually 11. Vegetation 11a. Distance to Important
Indigenous/ Remnant Vegetation
__ Mapped at local scale, not considered critical for regional criteria.
Notes: (1) "Non-mappable" criteria are indicated in Table 1.
The following criteria were not able to be mapped or were superceded by other criteria: ● Noise ● Shadow flicker ● Wind farm layout In addition to "non-mapable" criteria, the following criteria were not used for a number of reasons, primarily lack of dependable
data: ● Cell phone towers (4b) ● Mountain catchments (7a) ● Private nature reserves (7c) ● Distance to 1:100 year floodline (8c) ● Height above local topography (10a)
(2) Coastlines are typically areas of high wind resource, but also usually of high environmental and aesthetic value. However, for purposes of consistency and comparison, a standard 4km buffer was used in Method 1. (See however, recommended method which attempts to include coastal areas based on low scenic value.)
(3) Distance between separate wind farms (which was indicated in the "Original Table 7" from the PGWC report) with its suggested
buffer of 2,5km (being the Danish model) was not used in Methodology 1, but has been referred to in detail in the recommended regional methodology.
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4. OUTPUT AND ANALYSIS 4.1 Individual Criteria and Mapped Layers The individual map layers of the various criteria are presented in Appendix A to this report. Appendix B contains general comment on the individual mapping layers of each of the main criteria and their subsets as illustrated in Table 1. 4.2 Spatial Output The composite maps of the 10 main criteria groups and consolidated output map are presented on the following pages:
• Infrastructural layer (Map 1) • Environmental Planning layer (Map 2) • Composite layer all criteria (Map 3) • Available land (Map 4)
The quantification of the spatial output (Maps 1 – 4 following based on Maps A1 – A9 and B1 – B12 in Appendix A) is presented in Section 4.3. 4.3 Summary of Output The final output map (Map 4) illustrating available land (hypothetically) suitable for WE development is clearly based on the lack of existence of negative criteria buffers based on the thresholds indicated in Table 1. It is evident that a very large area (primarily in the eastern and central part of the study area) is identified for WE development. This area is approximately 1025km² which represents approximately 19,2% of the total study area (5337km²). A possible criticism of the method to this stage is that ALL areas falling under a threshold buffer regardless of its relative importance are mapped out from any possible wind energy development zone. This does not take account of relative importance of criteria and for this reason the criteria were ranked in order to attempt a more fine-grained output map discussed in the following section. 4.3.1 Alternative Assessment (Appendix C1) However, in order to demonstrate the sensitivity of the results to single criteria, Appendix C to this report illustrates a comparative output map (Map C1) to that presented in Map 4. This output map was based on a reduced threshold for larger airports with primary radar (Cape Town International Airport and Langebaanweg were reduced from 25km to 15km, but Hopefield Military Air Base was increased from 2,5km to 15km. Local airfields were reduced from 2,5km to 1,0km. It is evident from the output map in Appendix C, that, based on these revised criteria, a marginally larger area is available for WE development, comprising approximately 1163km² or approximately 21,8% of the study area. 4.3.2 Possible wind energy Zones (Appendix C2) Map C2 in Appendix C illustrated a broad zonation of possible WE development zones, based on Map C1 discussed above. Map C1 illustrates approximately 7 discreet or discernable areas which could be used as the basis for a regional locational framework which could also deal with the concern related to cumulative impact. (This issue is dealt with in detail in the Recommended Regional Method.)
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4.3.3 Impact of Airfields (Appendix C3) Map C3 in Appendix C illustrates in graphic terms the profound impact of the buffers applied to airports and airfields as discussed in 4.3.1.
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Map 1: Infrastructure Criteria
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Map 2: Environmental & Planning Criteria
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Map 3: Composite - All Criteria
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Map 4: Available Land
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5. REVISED OUTPUT In an attempt to fine tune and make Method 1 more robust, a revision to the output map illustrated in Map 4 is discussed below. (A revised output map is illustrated in Map 5). 5.1 Ranking of Criteria In the South African context, especially given the fact that we enjoy relatively undisturbed scenic and wilderness landscapes that remain vital to the tourism industry, it is suggested that the criteria defined in Table 1 are ranked according to their relative importance, firstly, from the technical or infrastructural perspective of wind turbine location (e.g. radar/airports), and secondly from the perspective of landscape conservation, as far as possible defined through criteria based analysis (i.e. mapped reserves etc.). Although Methodology 2 (Report 3 following) is to focus on landscape assessment, it is important to note that Method 1 already implicitly incorporates a level of landscape value by the inclusion of designated or protected areas, as well as the inclusion of scenic drives and coastlines. Table 2 below puts forward a suggested ranking of the criteria contained in Table 1.
Table 2: Suggested Ranking of Criteria
High Medium Low 1. Urban X 2. Residential X 3 a. National Roads X b. Local Roads X c. National/Provincial Tourist Route X d. Local Tourist Route X e. Railway Line X 4 a. Power Lines X b. Communication Towers X c. Navigation Beacons X 5 a. Primary Airfield Radar X b. Local Airfield X c. Security Sites X 6. National/Provincial Parks X 7 a. Mountain Catchments X b. Protected Natural Environments X c. Private Nature Reserves X 8 a. Coastline2 X b. Rivers X c. Floodline X 9 a. Major (Ramsar) wetlands X b. Local Wetlands X c. Bird Habitats/Routes X d. Vegetation X
10a. Topographical (elevation) X b. Ridge Lines X
2 Scenically disturbed or degraded coastlines are excluded from high value. This issue is explored further in the recommended regional method.
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6 11 9 Although an element of subjectivity exists, the suggested ranking of criteria is primarily based on: • The philosophical departure points expressed in the summary report, namely that WT
location should primarily be near urban landscapes, particularly brownfield sites, or disturbed vertical landscapes.
• The primary importance of certain infrastructural criteria such as airport radar. Of all the criteria used in Method 1, 6 are defined as of high importance, 11 of medium and 9 of lower ranked importance.
5.2 Scoring of Criteria HIGH MEDIUM LOW HIGH 6 5 4 MEDIUM 5 4 3 LOW 4 3 2
Note: That 7 is where there is an overlap of all 3 ranks (High + Medium + Low) 5.3 Revised Output Map This map (Map 5) has been created using the ranking of criteria illustrated in Table 3 above and a "Sieve" technique of illustration. High, medium and low values applied to the criteria are overlaid in order to illustrate degree of overlap, and therefore relative degree of importance of particular areas for exclusion of wind technology or possible negotiation should only a single low value criteria be applicable. The output map based on a layering of ranked criteria is therefore able to illustrate areas that were previously excluded from areas identified as potentially suitable for wind turbines, but that have only low value criteria applicable, that could allow wind development subject to mitigation at the local level. It should be noted that the following criteria were manipulated or varied for the purpose of the second output map. • National security zones were reduced from 15km to 5km (more appropriate and is
broadly, consistent with the existing Koeberg exclusion zone). • National Road N7 buffer reduced from 3 to 2km assuming it has less importance from a
tourism and scenic perspective and that visibility of a major wind farm will be of extremely short duration.
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Map 5: Revised (Ranked) Output Map
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6. CONCLUSIONS: METHODOLOGY 1 The major conclusions that flow from this report on Methodology 1 are: 6.1 The extent of thresholds applied to the criteria can be critical in determining the areas
available for wind turbines. (During the work on Method 1, the original criteria set defined by PGWC were run through the GIS model. This resulted in less than 8% of the study area being identified for wind technology. As illustrated on Table 2, the available land area increased to 22% of the study area on the basis of the recommended revised thresholds).
6.2 A key question that relates to residual area and thresholds is the atypical nature of the
study area in relation to provincial or South African conditions. It contains a large number of airfields, security facilities and unusual land uses that may not be found in other regions. The thresholds relating to these criteria require individual negotiation with the regulatory authorities. (This issue will obviously be applicable to any method chosen).
6.3 Ranking of the criteria in terms of importance suggests that a short set of critical
criteria can be derived that may be sufficient for an effective regional tool. This hypothesis is tested later in this project and is covered in Report 5 – Methodology 3.
6.4 As discussed in the introduction, wind energy developments have generally steered
away from urban areas, often to reduce the visibility and therefore the volume of objections. The adoption of the principal that wind energy developments belong only in rural areas, which underpins the approach of Method 1, should be questioned. This aspect is further dealt with in Methodology 3 (Report 5).
6.5 A further shortfall of this methodology that is apparent at this stage is the somewhat
limited ability to deal with landscape issues. These are only dealt with implicitly through the designation of protected areas and scenic routes. The relatively simple mapping of topography and slope, or indigenous vegetation coverage could only go part of the way to defining landscape value. This issue is dealt with in Report 4 – Comparative Assessment.
6.6 It must be recognized that since Method 1 excludes the mapping of positive criteria
(especially wind resource data), it does not necessarily follow that the areas identified for wind energy development (based on the lack of negative / exclusionary criteria) will be suitable for such development. Method 1 simply uses threshold criteria to define where wind turbines should not be located on the basis of safety, conservation or environmental or planning concerns. Once more robust wind resource data is made available this can be overlain with the output of Method 1 to highlight areas of potential for development assuming there will be overlap with the areas already identified.
6.7 Although Method 1 is based on a more quantitative approach which does not
incorporate the qualitative aspects of landscape value, the importance of certain landscapes is implicitly included by means of thresholds around formal protected areas. However, the lack of landscape character assessment and formal designations of areas of scenic beauty in South Africa creates a potential serious shortfall in the output of Method 1. This is discussed further in the Comparative Assessment.