4 PROJECT ALTERNATIVES

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1 4 PROJECT ALTERNATIVES As per the EIA Regulations published in Government Notice R543 of 18 June 2010 in terms of Section 24 (5) of the National Environmental Management Act (Act No. 107 of 1998), feasible and reasonable alternatives have to be considered within the EIA process. Hence a key challenge of the EIA process is the consideration of alternatives1. Most guidelines use terms such as reasonable, practicable, feasible or viable to define the range of alternatives that should be considered. Essentially there are two types of alternatives: Incrementally different (modifications) alternatives to the Project; and Fundamentally (totally) different alternatives to the Project. Fundamentally different alternatives are usually assessed at a strategic level, and EAPs recognise the limitations of project-specific EIAs to address fundamentally different alternatives. Electricity generating alternatives have been addressed as part of the National Integrated Resource Plan (NIRP) published by the Department of Energy and the Integrated Strategic Electricity Plan (ISEP) undertaken by Eskom. Environmental aspects are considered and integrated into the NIRP and ISEP using the strategic environmental assessment approach, focussing on environmental lifecycle assessments, water-related issues and climate change considerations. During the Scoping Phase, only alternatives in terms of a proposed Langhoogte Wind Farm in the Western Cape Province were considered. The entire project could be considered as an alternative source of energy to our current use of coal based power. The applicant is in the business of harnessing wind power for electricity and has therefore not considered another means of generating electricity for this particular project. 4.1 Alternatives considered in this EIA Alternatives considered in this Environmental Impact Assessment Report include: The no-go option; Location alternatives; Positioning of the wind turbines and electricity transmission line (alternative layouts); Many small turbines versus less large turbines scenario; and Land use alternatives. 1 In terms of the EIA Regulations published in Government Notice R543 of 18 June 2010 in terms of Section 24 (5) of the National Environmental Management Act (Act No. 107 of 1998), the definition of alternatives in relation to a proposed activity, means different means of meeting the general purpose and requirements of the activity which may include: (a) the property on which or location where it is proposed to undertake the activity; (b) the type of activity to be undertaken; (c) the design or layout of the activity; (d) the technology to be used in the activity; and (e) the operational aspects of the activity. Langhoogte Wind Farm EIA 4-1

2 4.2 The Do Nothing Alternative The do-nothing or no-go alternative is the option of not establishing a wind farm. The electricity demand in South Africa surpassed existing power generation capacity in 2008, causing nation-wide black-outs and load shedding. South Africa requires additional capacity if it is to meet the growing demand for electricity. The 'do nothing' option will, therefore, contribute to these electricity demands not being met. Not meeting the growing electricity demand will have major adverse impacts on economic activity and economic growth in South Africa, which in turn will have an adverse impact on socio-economic development in South Africa. Additional electricity generation options will contribute to meeting this energy demand. The recent increase in oil prices, the exhaustibility of fossil fuels and the urgent need for stable, reliable, non-polluting sources of electrical energy that are indispensable to a modern industrial economy focuses attention on alternative energy, such as renewable energy sources. The construction of the proposed wind farm will also aid South Africa in meeting its commitments to reduce green house gas emissions, made in terms of the United Nations Framework Convention on Climate Change (1997) and the Kyoto Protocol (2002) The do-nothing alternative will not assist the country in meeting these renewable energy targets or aid in reducing the Western Cape Province s dependence on imported electricity. The Do Nothing or No Go scenario will mean the opportunity for economic upliftment in the area is lost. A minimum of R560 million (over the 20 year life of the project at 2011 values) will be received by the local community from the proposed project through taxes and dividends earned from the 20% local community stake in the project. These funds will be applied to both local economic development and social upliftment projects. The do-nothing alternative is not considered as the preferred alternative in the proposal. The do-nothing alternative, however, is represented by the status quo, presented in Chapter 7, against which the proposed project has been compared in detail during the Impact Assessment Phase of the project. Should the proposed Langhoogte wind farm not be granted an environmental authorisation, the do-nothing alternative will prevail and the environment will remain as described in detail in Chapter Location Alternatives In determining the most appropriate sites for the establishment of a new wind farm within South Africa, various options were investigated by SAGIT during a prefeasibility study. The pre-feasibility site selection process has to consider particular criteria suitable to the development of a wind farm. Langhoogte Wind Farm EIA 4-2

3 The criteria, which resulted in the selection of the proposed study area included following: Topography The Theewaterskloof Municipal region is ideal for wind energy, characterised by an elevated plateau and numerous hills/ridges for the placement of turbines. These topographic features intensify the localised wind by causing a funnelling effect Wind Conditions (Renewable Resource) SAGIT has indicated that wind monitoring studies undertaken during the initial feasibility studies and data collected from the test mast located on De Vlei Farm (Parcel No. 350/2), have shown the local wind conditions to be ideal for the placement of a wind farm Extent of Site The large extent of the properties available allows for the installation of electricity generating capacity in one central location Connection to the National Transmission System ( the Grid ) An existing Eskom regional distribution substation is located south of Botrivier thus allowing for connection to the grid. This is a key issue influencing the location of the development. Existing power lines run in a north-south orientation through the western extremity of the site (Land Parcel 791/RE) and in an east-west direction through the southern section of the site (Land Parcels 362/1, 362/2/RE, 362/RE, 357/2 and RE/357). The availability of suitably located sub-stations is a significant limiting factor when siting a WEF. Research by SAGIT (unpublished) examined the suitability of existing sub-stations in terms of their suitability to act as connection points for potential WEF projects. They considered evacuative capacity (i.e. ability of the sub-station to accept further electricity), local topography (steep slopes associated with mountainous regions are not suitable), and suitability of the wind regime. A total of 107 substations were assessed in the Western Cape, and 80 sub-stations in the Eastern Cape. They concluded that there are potentially 8 and 7 suitable sub-stations, respectively; 15 in total. The Integrated Resource Plan of South Africa (IRP 2010) states that South Africa is to realise 8,400 MW of wind energy by Considering that to date 1,197 MW of wind energy has been allocated in the IPP Bid Windows 1 and 2, there remains theoretically 7,203 MW of wind energy to be allocated by The IPP procurement programme currently limits the size of individual wind farms to 140 MW. This essentially means that in terms of the IPP a further 51 wind farms (minimum) are to be realised in South Africa by Approximately 93% of MW allocated to date (Bid rounds 1 and 2) have been in the Eastern and Western Cape, largely due to the favourable wind resource. This suggests that the remaining 7,203 MW of wind electricity will also likely come from these two provinces, creating a scenario where 15 connection points are to accommodate 51 WEFs. This analysis highlights the value of each potentially viable connection point and the importance of critically evaluating the possibility of using each site. Langhoogte Wind Farm EIA 4-3

4 4.3.5 Environmental Considerations No environmental fatal flaws were identified during the initial feasibility stages. Construction and operation of the wind farm would not restrict the current farming/grazing activities on the site. The specialist environmental studies have identified environmentally sensitive areas located on the site and corresponding preferred locations for the proposed wind turbines. These have been considered in the proposed layout Site Access The proposed site is dissected by the R43 making access to both the western and eastern portion of the site fairly easy. Furthermore, the R43 provides access to the N2 which runs through the south easterly section of the site. With construction of a few access routes, the site can therefore be easily connected to these major routes making for easy accessibility for the transport of infrastructure and personnel Local Labour and Economic Stimulus Wind farms are well suited to rural areas as agricultural activities can continue around the wind turbines. In a number of cases, wind farms have led to an increase in tourism as they are considered by many to be a tourist attraction. Additionally, tourism accommodation will be utilised during the construction phase by project staff. The site is located in relatively close proximity to the towns of Caledon and Botrivier, which will act as a source of local labour. The site includes all those farms SAGIT has under contract and therefore only these areas are available to SAGIT for the development of a wind farm. No further sites are therefore considered in this EIA process. Other alternatives in respect of the proposed micrositing of turbines, and potential routing of the proposed powerline were identified and assessed in this EIA. 4.4 Layout Alternatives Wind Turbine Positioning Turbines are erected where the wind yield has been measured and modelled as optimal, but there are many other factors taken into account when turbines are positioned. The main principles observed are: Presence of most consistent and strongest wind; A willingness of farmers to accept wind turbines on their land; A suitable substrate for the foundations; Avoidance of steep slopes; Avoidance of ecologically sensitive areas; Avoidance of sensitive heritage sites; Close to each other to minimise the length of the access roads and collection cables, yet distant enough from each other (>400 m) to avoid interference ( dirty air ), Langhoogte Wind Farm EIA 4-4

5 Close to established roads and electricity grid infrastructure; Situated in terrain accessible for trucks carrying abnormal loads; At least 400 m distance from inhabited dwellings. Based on the above principles, as well the outcomes of the specialist investigations, a total of 44 potential turbine sites were identified during the EIA process. This layout was arrived at through a lengthy iterative process comprising three major and many more minor revisions. However, the locations of the turbines specified in Figure 4.1 should be treated as indicative because a detailed geotechnical analysis of each position has not been completed as yet. Turbine positions were specifically chosen to allow for small repositioning movements without intruding on identified sensitive areas Evolution of the Wind Turbine Layout The proposed Langhoogte Wind Farm EIA underwent numerous iterations of the project development plan in order to find the most acceptable solution from an environmental and from a technical perspective. The iterations can be divided into three major layouts which correspond to the start, the scoping phase and the EIA phase respectively. The three different layout phases are introduced below and are depicted in Figure 4.1. An initial layout of the wind turbines was provided by SAGIT at the beginning of the EIA in November The initial arrangement of the proposed wind turbines was determined using computational fluid dynamics 2 by internationally experienced meteorological expert companies. Layout 1 consisted of 31 turbines and its focus was on maximising the wind yield. Some of these were placed on neighbouring farm portions in the north that since are no longer available to SAGIT. Early feedback from specialists during scoping indicated that Layout 1 did not respect mandatory buffers. It also was severely compromising ecological requirements. For these reasons the first major revision of the layout became necessary. The revision occurred in three steps (January, May and July/August 2012), progressively moving turbines around in response to findings made by the specialists in the field as well as fine tuning SAGIT's responses to the technical constraints acting on site. Nineteen more turbines were added to the layout at this time, bringing the total to 50, as it is good planning practice to probe the capacity of the study site to accommodate turbine positions. Near the time of the release of the final Scoping Report it became clear that all 50 turbines could not be sustained. Due to the flux of the planning process, no specific turbine layout was presented in the Scoping Report. Layout 2 was subsequently developed consisting of 45 turbines clear of mandatory buffers and highly sensitive environments. Layout 3 was developed during the EIA phase from September 2012 onwards in response to intensified field work by the appointed specialists, constraints mapping and input from stakeholders. In the south, one turbine was moved as it was perceived to intrude too deeply into potential bat feeding habitat and was too close to a Telkom microwave link line. Likewise, two turbines were moved from the north-west to the east because of a predicted conflict with bat habitat. Further iterations became necessary to accommodate substantial buffers around public roads motivated for by 2 Computational fluid dynamics uses numerical methods and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with surfaces defined by boundary conditions. Langhoogte Wind Farm EIA 4-5

6 the visual and heritage specialists. Thus, the final number of Layout 3 consisted of 45 turbines clear of mandatory buffers and highly sensitive environments. The final layout (Layout 4) now consists of 44 turbines. One of the turbines (number 15) was omitted as recommended by the avifauna specialist in February when a number of blue crane nests were identified on site. Turbine 15 (north-eastern corner) fell within the 500m nest buffers recommended by the specialist. This removal of turbine 15 and its access road was undertaken after the review of the deir, and as such this change is not reflected in the specialist reports, with the exception of avifauna. However the removal of a turbine would likely be associated with a reduction in the significance of negative impacts on the site and as such would not alter the conclusions of the specialist studies. The removed access road to turbine 15 is illustrated in Figure 4.2). Layout 3 shown in Figure 4.1, i.e. the large black dots, has been assessed by all specialists in this EIR. Colour coding of turbine positions is used in Figure 4.1 to show the evolution of the turbine layout for the period November November The final position of each turbine is then shown as the largest and darkest (black) circle in the map: Table 4.1: Colour coding of turbine positions in Figure 4.1 during the various EIA phases Date Colour EIA phase Nov 2011 Pre-application Jan 2012 May 2012 Aug 2012 Sep 2012 Scoping Oct 2012A Oct 2012B Nov 2012 Feb 2013 EIR Turbine 15 was dropped post deir Figure 4.1 also shows that the mountainous part west of the high-voltage Eskom power lines carries no turbines at all in the final layout and that no turbines have been located close to the town of Botrivier. Likewise, no turbines are placed in the south of the study area near the N2 and beyond. Langhoogte Wind Farm EIA 4-6

7 Figure 4.1: Evolution of the turbine layout during the various project stages. Note turbine 15 has since been dropped. Langhoogte Wind Farm EIA 4-7

8 4.4.3 Evolution of the Access Road Layout The road and trench layout was assessed in all the specialist studies and found to be acceptable. The wetland specialist assessed impact associated with this road layout to be of low significance, however he listed 6 recommendations for minor changes to improve the road layout, which would then result in an overall design-phase impact on wetlands of very low significance. These recommendations were as follows: The connection road to the east of turbine 41 should not be built. Instead, turbines 3, 35 and 41 should connect with the road leading to turbines 17 and 19 via the loop between turbines 3 and 24. This would eliminate the need for a road crossing of the drainage channel of moderate conservation importance immediately south of turbine 41. The road to the north of turbine 10 should be moved at least 30 m (although preferably closer to 100 m or more) away from the edge of the wetland of high conservation importance to the north. The loop road north of turbine 20 should be moved at least 30 m away from the edge of the drainage channel of moderate conservation importance. The road to the east of turbine 29 should be moved at least 30 m away from the edge of the section of drainage channel marked as being of moderate conservation importance. The road immediately to the east of turbine 32 should be moved at least 30 m away from the edge of the wetland of moderate conservation importance. The road to the west of turbine 26 should not cross the wetland of moderate conservation importance twice. Instead, a single crossing at the northern end of the wetland (against the railway line) should suffice. From this crossing the road could link with turbine 26, making sure that the road does not encroach within 30 m of the eastern edge of this wetland. These recommendations have been accommodated in the final proposed road layout illustrated in Figure 4.2. Note this figure shows the final changes in road layout in different colours (red sections have been abandoned and green sections have been added) so the reader can clearly see the changes. Cable trenches will follow the roads. The access road leading to turbine 15 was removed following the omission of turbine 15 from the final layout Evolution of the 132 kv Transmission Line Layout Due to the need for wind turbines to be electrically connected to the substation, and then to the national transmission system, it was necessary to identify potential alignments for the power lines. The turbines produce electricity with an electromotive force (voltage) of 690 V that is transformed at the turbine to 11 or 22 kv. Transmission cables between closely spaced individual units are to be buried underground and then converge at an internal substation, where the voltage is transformed once more for external transmission by means of a 132 kv overhead power line to the Eskom Houwhoek Substation located south of Botriver. Langhoogte Wind Farm EIA 4-8

9 Figure 4.2: Final microsighting for this application. Finalised access roads for turbine assembly during the construction. Note the final amendments, as per wetland and avifauna specialist s recommendations, have been shown in red. These sections have been abandoned. Langhoogte Wind Farm EIA 4-9

10 Alternative corridors for the external transmission lines have been investigated. Four alignments marked Northern, Southern 1, Southern 2 and Southern 3 (see Figure 4.3) were assessed by the specialists during the EIA phase. Option S1 was identified by SAGIT as their preferred option for a number of reasons: It is the shortest route (see Table 4.2) The northern route posses engineering challenges namely having to cross existing powerlines of varying voltages at various heights at least 7 times. This is especially problematic at the Houhoek Pass where there are already a number of lines crossing the N2. There remains a possibility of Eskom utilising this line in the future. Eskom have indicated (see letter from Eskom below) that they plan to strengthen the connection between the Houhoek substation and Caledon in the future. Should this go ahead, it is possible that the proposed SAGIT line could serve as the first leg of the future Houhoek Caledon 132 kv line, thereby reducing the total number of lines needed in the area. Langhoogte Wind Farm EIA 4-10

11 Table 4.2: Length [km] of transmission line alternatives investigated in this EIA. Alternative Length [km] N 10.2 S1 7.4 S2 8.4 S The majority of the specialist studies confirmed that Southern Route 1 would be associated with the least impacts (see Table 4.3). Where specialists found that the Southern Route 1 option was not necessarily the preferred route, none of the anticipated impacts associated with this S1 route were deemed fatal flaws: Table 4.3: Length [km] of transmission line alternatives investigated in this EIA. Preferred Route Specialist study Northern Route Southern Option 1 Southern Option 2 Southern Option 3 Comments The northern route is preferred as the line crosses the shortest distance of agricultural land (habitat for Blue Cranes and Denham s Bustard). Northern route Avifauna traverses 4602m of agricultural land while S1 route traverses 6503m. The Southern route option 1 is the preferred southern route, as this line has the shortest section of the three options crossing agricultural areas. Bats Powerlines excepted to have a negligible effect on bats so no preferred route Ecology Southern route option 1 is preferred provided towers Aquatic and wetlands Visual Noise Heritage Economics Social Agriculture are placed outside areas on renonsterveld. With mitigation measures all the powerline routes are rated as low significance. Mitigation involves re-routing of sections of line to avoid aquatic ecosystems The S1 route is preferred because it would follow, over the majority of its route, the N2, an established infrastructure corridor. It would also not have to cross the Bot River valley (as is the case with the Northern Route). The S1 route is preferred because it would follow, over the majority of its route, the N2, an existing source of noise. Southern route option 3 is the preferred alternative from a heritage perspective however all of the southern routes are deemed acceptable. Southern Route Option 1 will have the lowest visual intrusion on views of the Bot River Valley from homesteads and tourism facilities lower down in the valley. Southern Route option 1 does not cross a residential development area and is also located along the alignment of the N2, which supports the recommendations contained in the PSDF for power lines. Northern route is preferred because, of all options, it traverses the least agricultural land. Option S1 is the second most favorable. Considering the specialists evaluation above, the Southern Route 1 option is considered to be the preferred route, associated with the least impacts. Langhoogte Wind Farm EIA 4-11

12 A B Figure 4.3: Alternatives considered for the 132 kv powerline (Northern route = pink, Southern Route 1 = blue, Southern Routes 2 and 3 = Green). The Southern Route 1 (blue) is preferred). This was altered to that shown in B (red section abandoned), in response to recommendations from the wetland specialist not to cross the valley system which the red section does. Langhoogte Wind Farm EIA 4-12

13 4.5 Design Alternatives Many small turbines versus less large turbines scenario The scale of the facility will have an influence on the risk. According to Kingsley and Whittam (2005), More turbines will result in more collisions [with birds]. Although only two bird mortalities have been recorded at the experimental site at Klipheuwel, the difference between the 3 turbines at Klipheuwel and the proposed 44 turbines at the proposed Langhoogte site are significant. Larger facilities also have greater potential for disturbance and habitat destruction. The rotor design and dimensions also play a role. To date it has been shown that large turbines kill the same number of birds as smaller ones (Howell 1995, Erickson et al. 1999). This means that with newer technology and larger turbines, fewer turbines are needed for the same power generation, possibly resulting in less mortalities altogether (Erickson et al 1999). By using a combination of the largest turbine models in the range of 3 to 3.5 MW each the Langhoogte wind farm has responded positively to the issue of turbine size. Spacing between turbines at a wind facility can have an effect on the number of collisions with birds. Some authors have suggested that paths need to be left between turbines so that birds can move along these paths. For optimal wind power generation, relatively large spaces are required between turbines in order to avoid wake and turbulence effects. This constraint was responded to by placing turbines into all parts of the wind farm site where constraints did not prevent this. 4.6 Conclusion This chapter discusses the various project alternatives involved with the proposed wind farm. The selection of the location for the proposed wind farm is discussed, as well as the various layouts, associated infrastructure alternatives and technology. The various criteria for the selection of the above alternatives are discussed in detail in the chapter. Assessment of these alternatives is included in the various specialist studies discussed in Chapters The evolution of the proposed wind farm layout is presented in Figures 4.1, and the final proposed layout and access road layout is presented in Figure 4.2. The final proposed overhead powerline route is presented as the Southern Route 1 option (blue line) in Figure 4.3 (B). Langhoogte Wind Farm EIA 4-13