Wind Resource Mapping in Zambia CANDIDATE SITE IDENTIFICATION REPORT JULY 2015 This report was prepared by DNV GL, under contract to The World Bank. It is one of several outputs from the wind Resource Mapping and Geospatial Planning [Project ID: P145271]. This activity is funded and supported by the Energy Sector Management Assistance Program (ESMAP), a multi-donor trust fund administered by The World Bank, under a global initiative on Renewable Energy Resource Mapping. Further details on the initiative can be obtained from the ESMAP website. This document is an interim output from the above-mentioned project. Users are strongly advised to exercise caution when utilizing the information and data contained, as this has not been subject to full peer review. The final, validated, peer reviewed output from this project will be the Zambia Wind Atlas, which will be published once the project is completed. Copyright © 2015 International Bank for Reconstruction and Development / THE WORLD BANK Washington DC 20433 Telephone: +1-202-473-1000 Internet: www.worldbank.org This work is a product of the consultants listed, and not of World Bank staff. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work and accept no responsibility for any consequence of their use. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. The material in this work is subject to copyright. Because The World Bank encourages dissemination of its knowledge, this work may be reproduced, in whole or in part, for non-commercial purposes as long as full attribution to this work is given. Any queries on rights and licenses, including subsidiary rights, should be addressed to World Bank Publications, The World Bank Group, 1818 H Street NW, Washington, DC 20433, USA; fax: +1-202-522-2625; e-mail: pubrights@worldbank.org. Furthermore, the ESMAP Program Manager would appreciate receiving a copy of the publication that uses this publication for its source sent in care of the address above, or to esmap@worldbank.org. RENEWABLE ENERGY WIND MAPPING FOR ZAMBIA Candidate Site Identification Report The World Bank Document No.: 702833-USSD-R01-D Issue: D, Status: FINAL Date: 3 July 2015 IMPORTANT NOTICE AND DISCLAIMER 1. 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Commercial in Confidence : Not to be disclosed outside the Customer’s organisation. DNV GL only : Not to be disclosed to non-DNV GL staff Distribution for information only at the discretion of the Customer (subject to the above Important Notice and Disclaimer and the Customer’s Discretion : terms of DNV GL’s written agreement with the Customer). Available for information only to the general public (subject to the Published : above Important Notice and Disclaimer). DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 4 www.dnvgl.com Project name: Renewable Energy Wind Mapping for Zambia DNV GL - Energy Report title: Candidate Site Identification Report Renewables Advisory Customer: The World Bank, 9665 Chesapeake Drive, Suite 435 1818 H Street, N.W. San Diego, CA 92123 Washington, DC 20433 Tel: 703-795-8103 Contact person: Francesca Fusaro Enterprise No.: 94-3402236 Date of issue: 3 July 2015 Project No.: 702833 Document No.: 702833-USSD-R01-D Issue/Status D/FINAL Task and objective: Identify a long list of suitable wind measurement locations for the purpose of calibrating the mesoscale wind map for Zambia, and to provide technical details of the type of equipment proposed. Prepared by: Verified by: Approved by: Shant Dokouzian Craig Houston Richard Whiting Senior Project Manager, Development and Senior Advisor, Strategy & Policy Service Line Leader, Project Development Engineering Services Francis Langelier Daran Rife GIS Team Leader, Environmental and Global Head of Mesoscale Modelling Permitting Services [Name] [Name] [title] [title] ☐ Strictly Confidential Keywords: ☐ Private and Confidential World Bank, Zambia, Wind, Measurement, tower, ☐ Commercial in Confidence mesoscale, map, GIS, validation, constraints ☐ DNV GL only ☒ Customer’s Discretion ☐ Published © Garrad Hassan America, Inc.. All rights reserved. Reference to part of this report which may lead to misinterpretation is not permissible. Issue Date Reason for Issue Prepared by Verified by Approved by A 22 October 2014 FINAL B 12 November 2014 Update coordinates in Table 3-7. Minor aesthetic changes to maps. Incorporated correction identified by World Bank on page 6, added C 22 December 2014 required Cover Page and Terms of Use, modified version to “FINAL” DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 5 www.dnvgl.com Table of contents 1 INTRODUCTION ............................................................................................................................. 7 1.1 Project description ....................................................................................................................... 7 1.2 Framing the challenge.................................................................................................................. 8 2 GENERAL APPRECIATION OF ZAMBIA LANDSCAPE AND WIND RESOURCE ............................................. 9 3 MAST SITE IDENTIFICATION AND RANKING .....................................................................................11 3.1 Methodology ..............................................................................................................................11 3.2 Mapping of spatial features and constraints ...................................................................................12 3.3 Multi-criteria analysis ..................................................................................................................13 3.4 Site identification and ranking ......................................................................................................20 4 MEASUREMENT MAST SPECIFICATIONS AND RECOMENDATIONS ........................................................24 4.1 Mast 24 4.2 Equipment .................................................................................................................................24 4.3 Other equipment ........................................................................................................................26 4.4 Measurement configuration .........................................................................................................27 4.5 Documentation ..........................................................................................................................32 5 REFERENCES ................................................................................................................................34 APPENDIX A – SPATIAL FEATURES AND CONSTRAINTS MAPPING ..........................................................35 List of tables Table 3-1 Exclusion areas ................................................................................................................ 13 Table 3-2 Relative weighting of identified criteria and factors ............................................................... 15 Table 3-3 Distance to road scoring system ......................................................................................... 17 Table 3-4 Distance to urban areas scoring system .............................................................................. 17 Table 3-5 Potential security scoring system ........................................................................................ 17 Table 3-6 Ranking matrix................................................................................................................. 21 Table 3-7 Proposed sites for wind measurement masts – details ........................................................... 22 Table 4-1 Instrumentation Summary ................................................................................................. 29 List of figures Figure 2-1 Preliminary and unvalidated mesoscale wind speed map based on the full 10-year simulations.. 10 Figure 3-1 Methodological approach .................................................................................................. 11 Figure 3-2 Exclusion areas / available land for meteorological mast ...................................................... 14 Figure 3-3 Heat map for locating mesoscale wind validation masts ........................................................ 19 Figure 3-4 Proposed sites for wind measurement masts ....................................................................... 23 Figure 4-1 Recommended mast instrumentation ................................................................................. 31 DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 6 www.dnvgl.com 1 INTRODUCTION The results described in this report are derived from interim output and are preliminary and unvalidated, and they have not been subjected to full peer review. DNV GL does not guarantee the accuracy of the maps, data, and visualizations presented in this report, and accepts no responsibility whatsoever for any consequence of their use. Wind speed values shown in tables and maps should not be relied upon in an absolute sense. Rather they should be strictly interpreted as indicative (e.g., elevated windiness near mountaintops and escarpments). Users are strongly urged to exercise caution when using the information and data contained within this report. During Phase 2 of this project, measurements will be collected from a number of representative sites throughout the country over a 24 month period, and these will be used in Phase 3 to develop a final, validated, peer-reviewed suite of outputs from this project, which will be made available at the project’s completion. The World Bank (“Client”) has retained Garrad Hassan America, Inc. (“DNV GL”) to provide a validated mesoscale wind atlas for Zambia, including associated deliverables and wind energy development training courses. Validation of the wind atlas will be undertaken by installing several wind measurement meteorological masts throughout the country. Meteorological data collected at these sites over a 2-year period will provide the basis for validating the mesoscale modeling outputs. This report presents the initial findings of DNV GL’s investigation on appropriate wind measurement sites and will form the basis of further discussions with the World Bank and all relevant Zambia stakeholders, including the Ministry of Energy. This report also provides detailed specifications and recommendations for the measurement equipment proposed. 1.1 Project description Zambia is still in the early stages of exploring the resource potential for wind power, and to date there are no utility-scale wind turbines operating in the country. Furthermore, only a small number of low elevation meteorological masts exist, presenting a significant barrier to policymakers interested in evaluating the potential for wind energy in Zambia. The key goal of this project is to provide Zambian policy makers and stakeholders with accurate and valuable knowledge of the national wind resource which can be of direct practical use, both for formulating energy policy and implementing wind projects. The installation and operation of high quality wind measurements throughout the country will also strengthen local capacity to support future development of wind projects in Zambia. The primary deliverable supporting the above goal will be a well-validated national mesoscale wind resource atlas for Zambia that will greatly improve the awareness and understanding of the locations with the greatest potential for wind energy. When used in combination with a Geographic Information System (GIS), this forms a highly valuable planning tool which facilitates energy strategy planning for policy makers and stimulates commercial wind development by removing an important knowledge barrier. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 7 www.dnvgl.com This Site Identification Study focuses on the identification of suitable measurement locations to support the validation of the preliminary mesoscale wind atlas and should be viewed together with the Mesoscale Wind Modeling Report #1 [1]. DNV GL has identified a preliminary list of 31 promising sites for wind measurement masts in Zambia. Among these favorable sites, 12 locations will be shortlisted after consultation with the Department of Energy, the World Bank and other relevant stakeholders. Once an agreement is reached, a site visit will be performed at each of the shortlisted mast locations. Based on the field visits, a final group of 8 masts will be selected and deployed across Zambia to validate the mesoscale wind atlas. 1.2 Framing the challenge Zambia lies south of the Equator, extends over 750,000 km2 and shares borders with eight countries. The size of the country alone presents some significant challenges when designing a finite measurement campaign suitable for validating a national level wind atlas. Under this ESMAP funded initiative, a total of 8 masts will be deployed across the country for the purpose of validating the initial Phase 1 mesoscale mapping outputs described in [1]. In order to serve this purpose effectively, these masts must capture the different large-scale wind characteristics of the country; inform and improve the wind modelling in areas of uncertainty; and capture a sufficient spectrum of ground conditions represented in the four-dimensional atmospheric wind model. In addition to these technical requirements, a host of other practical issues such as site accessibility, terrain slopes, exclusion zones and environmental constraints must be factored into the selection of the best mast locations. Lastly, DNV GL has also analysed factors including distance to grid and wind speed which are considered important for future development of wind energy. These have been included so that masts may support the primary goal of validating the wind atlas and a secondary goal of supporting future development of areas with high potential for wind development. Section 3 explains in detail the multi-criteria methodology used to incorporate all of these important factors relevant to the selection of mast locations. DNV GL hopes that the Ministry of Energy and other relevant agencies will be actively involved in the selection process, help review the inputs and provide the local knowledge needed to ensure a successful measurement campaign with lasting value for Zambia. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 8 www.dnvgl.com 2 GENERAL APPRECIATION OF ZAMBIA LANDSCAPE AND WIND RESOURCE Before a detailed multi-criteria analysis can be undertaken to identify promising locations for installing measurement masts, it is essential to understand the characteristics of the wind conditions in Zambia and how these vary across the country. The Mesoscale mapping report is a key Phase 1 deliverable of this ESMAP project and it provides the most accurate picture of the wind resource in Zambia currently available. This map will be further improved by validating the modelling results with high quality measurements to be recorded over 2 years at the 8 mast locations. Figure 2-1 shows the preliminary mesoscale wind speed map, based on the full 10-year simulations performed with the DNV GL WMS system. This provides for the first time a detailed picture of the long-term wind resource across the country. From this map a number of interesting features of the wind climate in Zambia appear: Muchinga Escarpment: A large area of good wind resource exists along the length of the Muchinga Escarpment from the center of Zambia all the way to the Border with Tanzania in the northeast. The preliminary wind map suggests that good wind speeds extend well beyond the leading edge of the escarpment and across the plateau extending to the northwest. This could be a viable location for future mast deployment and wind development, particularly given the nearby road access and proximity to transmission lines (see Figure A-7). Eastern province: The eastern edge of Zambia along the borders with Mozambique and Malawi appear to have promising wind resource combined with relatively simple terrain. However, the limits of the current transmission system will likely limit large scale deployment of wind energy in the short-term. Central province: The central spine of Zambia offers some interesting wind resource potential that aligns well with existing infrastructure and load centers. Luangwa river basin and Lake Kariba: The environmentally sensitive areas around the Luanga River basin and Lake Kariba also happen to have some of the country’s lowest average wind speeds. These low lying regions have poor exposure to the predominantly easterly winds and are therefore not viable for commercial wind development. This alignment of poor wind resource and sensitive habitat is fortunate and may help prevent conflicts between wind development and important preservation areas. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 9 www.dnvgl.com Figure 2-1 Preliminary and unvalidated mesoscale wind speed map based on the full 10-year simulations DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 10 www.dnvgl.com 3 MAST SITE IDENTIFICATION AND RANKING 3.1 Methodology The preliminary selection of the most suitable locations for installing mesoscale validation masts has been conducted using a multi-criteria analysis specifically tailored to the project objectives and the country of Zambia. The primary objective was to select sites which provide the maximum potential for improving the accuracy of the mesoscale mapping; however secondary consideration has also been given to sites which show potential for future wind development. Practical factors such as ease of construction and maintenance and minimizing environmental and social impacts have also been central to the selection process. The methodological approach can be summarized in five main steps: 1. Mapping and identification of spatial constraints (e.g. environmental features, built features, wind resource and related uncertainty, security, topography, etc.); 2. Removal of areas of ‘hard’ constraint, defined as those which are entirely incompatible with the installation of meteorological masts (e.g. bodies of water, city centers, national parks); 3. Pragmatic weighting of the remaining area, outside the defined ‘hard’ constraints, to identify suitable sites for mesoscale validation meteorological masts, taking into consideration factors which influence the selection process; 4. Identification of the most promising sites (iterative process); and 5. Ranking, analysis, and description of identified sites. The above approach is described in greater detail in the following sections. Figure 3-1 Methodological approach DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 11 www.dnvgl.com 3.2 Mapping of spatial features and constraints DNV GL used readily available mapping data and other documentation available on the public domain, to prepare detailed maps showing land features, key environmental features, infrastructure and other key inputs deemed of influence in identifying site locations. Some information was also digitized from the Zambia Atlas [2] provided to DNV GL by ZEMA during the inception Mission held in Lusaka. The primary data sources are the following: • DNV GL preliminary mesoscale wind map, uncertainty index map and roughness map [1]; • Zambia Environmental Management Agency (ZEMA), Zambia Atlas of our changing environment, 2013; • African Development Bank Group, Africa Infrastructure Country Diagnostic; • U.S. Geological Survey (Shuttle Radar Topographic Mission Elevation Data, HYDROSHED Database); • Our Airport.com; • Open Street Map; • Environmental Systems Research Institute (ESRI); • Protect Planet, World Database on Protected Areas; • Birdlife International; • Ministry of Mines, Energy and Water Development, Zambia Mining Cadastre; • Google Earth; • Land Tenure Map: The colonial foundations of Zambia’s land tenure system, published by the National Educational Company of Zambia Ltd, 1980; • High level security considerations: US Department of State - International Travel, Government of Canada – Travel advice and advisories to Zambia, and UK Foreign travel advice (to be confirmed through discussion with Zambia Department of Energy and The World Bank). Appendix A, presents a complete set of maps covering the above GIS data, including primary outputs of the Mesoscale Wind Modeling Report #1. DNV GL notes that while the above list covers a wide range of inputs, it is not exhaustive, and the data for each feature may not be entirely up-to-date or complete. Therefore DNV GL would welcome feedback from any relevant agencies to assist in validating the public domain data used as the basis for this preliminary GIS site selection process. Additionally, the following data was not available for this initial assessment and may have significant impact on the site identification study: • Official Land tenure information and possible access issues related to ownership; • Military and other government-related exclusion zone; • Detailed local security considerations. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 12 www.dnvgl.com Any further guidance on how to obtain these and any other relevant data would be welcomed. 3.3 Multi-criteria analysis In order to capture the areas that are suitable for placing meteorological masts, DNV GL, in as a first step, has aimed to identify areas that should be entirely excluded. The remaining area is then referred to as the Available Area. This is further detailed in Section 3.3.1 below. As a second step, a map showing the relative appropriateness for placing masts across the Available Area is then created. This map is commonly referred to as a Heat Map. Through a weighting process, a colour scale indicates the areas highly relevant to placing a mast, up to the areas of least importance. This is further detailed in Section 3.3.2. 3.3.1 Exclusion areas As discussed above, the analysis identifies certain features or areas that are completely avoided for the installation of meteorological towers for mesoscale validation. This step helps limit the focus to suitable regions only, or Available Areas. Table 3-1 presents exclusion zones considered in this study as well as applied setbacks, where appropriate. These ‘hard’ constraints consist of a combination of technological barriers and spatial conflicts which are considered to restrict the installation of masts. Figure 3-2 presents the hard constraints and the available land considered in the site selection. Approximately 25% of Zambia is excluded from the analysis due to these constraints. Table 3-1 Exclusion areas Constraint Area excluded Maximum slope Slopes exceeding 15% Urban Areas Area within and up to 5 km from cities of 20,000 inhabitants and more Airports 10 km from International Airports and 5 km from National Airports Major radiocommunication System 10 km from radars (Air Surveillance Radar, Weather Radar) and 5 km from VORs Environmentally Sensitive areas National Parks, Migratory Bird Sanctuaries Rivers, lakes, wetlands and swamps (including Ramsar) Security 10 km from the Democratic Republic of Congo border DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 13 www.dnvgl.com Figure 3-2 Exclusion areas / available land for meteorological mast DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 14 www.dnvgl.com 3.3.2 Multi-criteria analysis of available area Locating the best sites among the Available Area is achieved by using a multi-criteria analysis and by generating a set of factors that will be used to produce a Heat Map. While a primary goal for locating masts is to validate the mesoscale wind map, secondary technical, social and environmental considerations as well as areas prone to future wind development were also considered. Areas close to existing road network and urban areas was highly considered as well for ease of maintenance. This was achieved by setting key Criteria for mast selection, and then associated factors. A relative weight was then attributed to each factor, for a total of 100%. This is detailed in Table 3-2. Table 3-2 Relative weighting of identified criteria and factors Relative Criteria Factor Weight [%] Area of optimal validation value a) Wind Uncertainty Index Map 25 b) Wind speed 15 Area prone to future commercial wind development c) Distance to Grid 10 Construction complexity d) Terrain slopes 10 e) Distance to roads 15 Ease of access / remoteness f) Distance to urban areas 5 Security g) Areas of potential security concern 5 Environmental and social h) Regulated or sensitive areas (Forest Reserves, Game 15 sensitivity Management Areas, Important Bird Areas) The relative weight of each factor in Table 3-2, and attribution of score within the Available Area is suggested based on DNV GL’s expertise in mesoscale wind mapping, wind energy development and mast installation. This is an area of potential discussion with stakeholders. Each Criteria and associated factor(s) is discussed below. Area of optimal validation value The primary project goal is to validate the mesoscale wind map. As such, a significant relative weight of 25% has been attributed to this item. The factor considered is the preliminary uncertainty index map, produced as part of the initial mesoscale mapping work. The preliminary uncertainty index is initially set to be equal to the standard deviation of nine multi-physics mesoscale ensemble members as described in [1]. Areas with a high index value, and therefore high standard deviation indicate an area where there is a lack of consensus between the nine multi-physics ensemble members, and shows the apparently increased difficulty in modelling the flows in these areas. A score of 0 to 10 is scaled to the range of preliminary uncertainty index from the analysis after exclusion of the outliers. As an example, a score of 0 would be given to an area on the map with the lowest index value resulting from the analysis, while a score of 10 would be given to an area on the map with the highest index value after exclusion of the outliers. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 15 www.dnvgl.com Areas prone to future commercial wind development Whilst the primary objective is to optimise the validation and ensure highest accuracy of the overall wind atlas, secondary use of the measurements in future individual wind farm developments is also foreseen as a value outcome. To capture this value, two factors which contribute significantly to assessing areas prone to wind energy development have been included, (i) long-term hub-height wind distribution, and (ii) the distance to, and availability of the electrical medium-voltage and high-voltage grid. Many other factors impact the assessment of future development potential, such as terrain complexity or environmental sensitivity; however, these are mostly captured in the other mast siting criteria. Wind Speed at a height of 100 m agl, from the work presented in [1],is used as the factor to represent the Long-term hub height wind speed. A score of 0 is given to wind speeds below 5 m/s, which represents a wind speed (with some margin due to the inherent uncertainty in the un-validated mesoscale outputs) at which utility-scale wind energy development is typically not viable. A score between 0 and 10 is then scaled to the range of speeds suitable for wind energy development. In summary, a score of 0 would be given to an area on the map with a wind speed below 5 m/s, while a score of 10 would be given to an area on the map with wind speed over 9 m/s. While capacity of existing medium voltage and high-voltage grid is of primary concern to wind energy development, such in-depth analysis is a significant undertaking and not part of this study’s scope. The distance to grid is therefore used as the metric, which is of importance on its own. New Transmission line construction will greatly influence a wind energy project’s capital cost (CAPEX). As such a score of 0 is given to areas more than 75 km from a known low voltage (33-88 kV), medium voltage (132-220 kV) or high- voltage (330 kV) transmission line. A score of 0 to 10 is then scaled to the distance from the transmission line, over a range of 75 km. In summary, a score of 0 would be given to a location at 75 km or beyond, while a score of 10 would be given to an area next to a transmission line. Construction complexity Construction complexity is a primary concern which can burden or even preclude an area for mast construction. As well, access is typically more challenging in generally complex terrain. As such, terrain of slopes above 15% has been considered as an exclusion zone, as discussed under 3.3.1. A relative weight of 10% has been given. A score of 0 to 10 has been scaled to sloped terrain of 15%, up to 0%. In summary, a score of 0 is given to slopes of 15%, while 10 is given to a flat area. Ease of access / Remoteness Two factors have been considered for this Criterion; ease of access and remoteness. A combined relative weight of 20% has been assigned to this Criterion. Ease of access for mast construction has been determined, at this stage, by considering distances to different type of roads. Proximity to roadway infrastructure will typically allow for easier construction and maintenance. Table 3-3 defines the scoring system used. The highest score would apply at any given location. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 16 www.dnvgl.com Table 3-3 Distance to road scoring system Road Type1 Range Score Highway 0 to 100 km 10 to 0 Secondary Road / Major Road 0 to 50 km 7 to 0 Road 0 to 25 km 3 to 0 1 DNV GL notes that available GIS roadway input files are incomplete Remoteness has been considered by assessing distance to known urban areas. Proximity to urban areas will typically allow for better access to supplies, construction crews, lodging, access, etc. Table 3-4 defines the scoring system used and the highest score that would apply at any given location. Table 3-4 Distance to urban areas scoring system Urban Area Type Range Score City over 250k inhabitants 0 to 350 km 10 to 0 City over 100k inhabitants 0 to 250 km 10 to 0 Town over 20k inhabitants 0 to 250 km 5 to 0 Security Security is of concern during the installation of the masts and operation. Masts are typically un-supervised and vandalism targets in remotes areas. Although security concerns will need to be discussed and properly assessed with the Client and the Zambian agencies, DNV GL has suggested some initial areas of potential concern from sources such as the American, UK and Canadian governmental web sites, and from its own internal health and safety policy. A low relative weight of 5% was given to allow for future discussions on this topic and a more thorough assessment with local stakeholders, as to not exclude a promising site that could be built and maintained with proper planning. Table 3-5 presents a suggested scoring for potential security concerns. Table 3-5 Potential security scoring system Area Range Score Borders with Angola, 0 to 50 km 0 to 10 Mozambique, and Zimbabwe from border 0 to 50 km Democratic Republic of Congo from exclusion 0 to 10 area1 Western Province, Zambia All 5 All other areas All 10 DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 17 www.dnvgl.com Environmental and social sensitivity Zambia hosts several areas with different statuses of protection for preservation. A relative weight of 15% has been attributed to this Criterion. Aside from the exclusion areas presented in Section 3.3.1, three other areas have been considered in the present study; Game Management Areas, Important Bird Areas and Forest Reserves. Although not areas restricted to mast installation, these areas present additional permitting challenges and interference with wildlife. The following scores were attributed: • Game Management Areas: score of 0; • Important Bird Areas: score of 3; • Forest Reserves: score of 5; and • All other areas: score of 10. Combined multi-criteria heat map Every area within Zambia was associated a score per factor, which was then weighted according to Table 3-2, as discussed above. The result is an initial multi-criteria heat map, which is shown in Figure 3-3. The purpose of this output is to present in a usable map format the combined scoring across the entire country, taking into account all weighting criteria simultaneously. As an example, a score of 7 or 8 out of 10 (green areas) would represent highly relevant areas for locating mesoscale wind validation masts. The heat map will serve as the primary tool for selecting the short-list of final mast locations and DNV GL looks forward to participating in an open and inclusive selection process involving all relevant parties. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 18 www.dnvgl.com Figure 3-3 Heat map for locating mesoscale wind validation masts DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 19 www.dnvgl.com 3.4 Site identification and ranking Utilizing the Heat Map, but also the various input maps presented in Appendix A, DNV GL selected proposed mast locations across Zambia. Over 30 locations were identified, offering good spatial coverage of Zambia and covering the wide range of land cover, or in terms of mesoscale modeling terminology, roughness length. Google Earth was used to micro-site the various locations and to verify if secondary roads would reach specific locations. From the aerial imagery, settlements were also avoided. It shall be noted that the present identification exercised was based on publicly available data and aerial imagery. Stakeholder engagement and local partner consultation will be required to identify the most promising sites out of the 30+ identified. A subsequent site visit will finally aid in ensuring desktop-selected sites are optimal and constructible. Additional micro-siting is expected during the site visits and potentially during the permitting process. The results are presented in the following table and figures: • The scores allocated for each factor, for each site, are shown in Table 3-6; • A brief site description for each site is shown in Table 3-7; and • Figure 3-4 presents the location of the proposed sites. As previously discussed under Section 3.2, official land tenure was not available. Client has indicated a preference for siting masts on Public Lands. An unofficial and preliminary land tenure map is presented in Appendix A. As per this map, Chingola, Lusaka II, Choma and Livingston would be located on State Land. All other masts would be on Customary Land. Mongu, Muketa and Sesheke would be located within the Barotseland Protectorate. It should be noted that the wind speed score presented in the table below does not represent the mean wind speed in meters per second. It is based on the score associated with wind speed, as discussed in Section 3.3.2. DNV GL ranking methodology is based on a set of factors and weighting that are dependent on the accuracy of the GIS information. DNV GL has not performed any on-site validation of features and cannot guarantee the accuracy of the information. Lastly, it should be noted that a different multi-criteria analysis method and factor weighting could lead to different results. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 20 www.dnvgl.com Table 3-6 Ranking matrix Area of Area prone to Environmental optimal Construction Ease of access / future commercial Security and social validation Complexity remoteness wind development sensitivity Final value Score Mast Name Rank (/10) Distance Areas of Wind Wind Distance Distance Terrain to Urban potential Regulated or Uncertainty Speed to Grid to Road Slopes Score Areas security sensitive area Map Score Score Score Score (/10) Score concern (/10) (/10) (/10) (/10) (/10) (/10) (/10) 100% 25% 15% 10% 10% 15% 5% 5% 15% Lusaka III 1 8.8 8.9 7.4 9.3 8.3 8.7 7.4 10 10 Lusaka II 2 8.3 7.4 6.5 8.3 9.1 9.2 7.7 10 10 Lusaka I 3 8.1 9.3 8.1 4.9 3.4 8.9 7.5 10 10 Livingstone 4 7.9 5.8 4.8 8.8 9.7 9.8 8.5 10 10 Old Petauke 5 7.9 8.1 4.6 8.1 8.7 8.5 4.8 10 10 Kabwe 6 7.8 6.4 7.4 9.8 7.6 6.7 7.3 10 10 Choma 7 7.8 6.5 6.2 8.9 8.3 8.8 4.6 10 10 Malawi Border 8 7.8 7.4 6.7 8.1 9.1 6.8 3.9 10 10 Chakansa 9 7.8 4.9 7.0 9.7 8.8 9.8 3.7 10 10 Chingola 10 7.7 5.6 5.5 8.7 9.7 9.1 9.2 5.8 10 Mpika II 11 7.6 3.4 7.9 9.9 8.4 9.9 4.3 10 10 Mpika I 12 7.6 4.0 7.3 9.9 9.9 8.3 4.6 10 10 Mkumpa 13 7.4 4.3 8.5 6.5 8.9 8.9 4.1 10 10 Chanka 14 7.4 6.3 8.7 6.6 6.8 7.4 1.6 10 10 Lundazi 15 7.4 6.7 5.6 9.2 8.5 6.6 2.5 10 10 Kawana 16 7.1 5.4 5.4 9.2 8.6 7.0 3.2 10 10 Mobola 17 7.1 7.2 5.3 7.0 9.6 4.1 4.3 10 10 Sesheke 18 6.9 6.7 4.1 8.9 9.7 5.4 4.8 5 10 Mkushi 19 6.9 5.7 7.2 9.8 0.0 8.7 6.3 5.1 10 Kasama 20 6.8 3.2 6.3 9.9 8.4 6.9 4.2 10 10 Mongu 21 6.7 5.7 4.6 8.2 7.6 7.0 4.8 5 10 Chale 22 6.7 3.9 2.8 9.5 9.4 8.5 3.0 10 10 Muchinga 23 6.2 6.0 6.9 3.2 7.4 2.2 4.7 10 10 Muketa 24 6.1 6.4 5.1 0.0 9.1 6.9 1.6 5 10 Mansa 25 6.1 2.8 4.7 7.2 9.3 7.0 4.4 6.3 10 North Western 26 6.1 5.5 4.7 0.0 9.5 6.9 1.0 10 10 Mporokoso 27 6.1 1.9 3.9 9.8 9.0 6.8 3.1 10 10 Mbala 28 6.1 3.5 5.9 7.2 7.1 4.4 4.4 10 10 Mwinilunga 29 5.9 3.1 5.0 0.0 8.7 9.9 2.1 7.3 10 Chilikita 30 5.7 4.7 4.3 0.0 7.2 6.9 2.1 9.8 10 Nayumba 31 5.6 3.5 3.7 5.7 5.8 6.1 2.8 10 10 DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 21 www.dnvgl.com Table 3-7 Proposed sites for wind measurement masts – details Distance to Distance the closest to the Terrain city with closest Roughness Elevation Mast Name Rank Latitude Longitude Province Slope population known Length [m] [%] over road 20,000 [km] [km] Lusaka III 1 -16° 4' 21.6" 27° 49' 20.5" Southern 6 2.2 26 0.2 1138 Lusaka II 2 -14° 47' 22.2" 27° 59' 8.8" Central 1 7.6 66 0.2 1163 Lusaka I 3 -15° 21' 18.7" 29° 3' 56.6" Lusaka 10 10.8 88 0.2 1131 Livingstone 4 -17° 37' 7.0" 25° 55' 17.8" Southern 0 1 29 0.2 1092 Old Petauke 5 -14° 11' 49.5" 31° 12' 33.7" Eastern 2 0.4 13 0.2 1005 Kabwe 6 -13° 58' 21.9" 28° 20' 58.2" Central 4 20.9 37 0.3 1315 Choma 7 -16° 49' 37.8" 26° 46' 52.0" Southern 3 10.1 24 0.1 1362 Malawi Border 8 -13° 8' 53.8" 32° 57' 9.1" Eastern 2 1.3 65 0.1 1054 Chakansa 9 -13° 7' 26.9" 30° 24' 14.7" Central 1 1.9 164 0.2 1529 Chingola 10 -12° 38' 2.9" 27° 45' 2.8" Copperbelt 0 9.3 16 0.2 1320 Mpika II 11 -12° 8' 39.4" 31° 13' 49.0" Northern 3 1.1 44 0.2 1392 Mpika I 12 -11° 38' 35.5" 31° 20' 27.4" Northern 0 1.4 24 0.2 1416 Mkumpa 13 -13° 50' 38.4" 32° 12' 23.3" Eastern 2 1.4 54 0.1 1037 Chanka 14 -9° 43' 14.9" 32° 58' 27.7" Northern 6 0.8 204 0.5 1283 Lundazi 15 -12° 23' 34.2" 33° 4' 7.9" Eastern 2 2.6 150 0.1 1143 Kawana 16 -13° 1' 14.5" 26° 4' 57.0" North Western 2 0.3 113 0.5 1394 Mobola 17 -16° 15' 51.0" 26° 42' 22.6" Southern 1 11.1 71 0.1 1180 Sesheke 18 -17° 21' 19.4" 24° 16' 35.3" Western 0 1.6 14 0.3 1014 Mkushi 19 -13° 43' 28.7" 29° 31' 37.9" Central 14 0.4 98 0.2 1489 Kasama 20 -10° 18' 37.0" 30° 45' 28.8" Northern 2 0.9 49 0.2 1421 Mongu 21 -15° 14' 51.7" 23° 14' 15.3" Western 5 0.1 10 0.2 1070 Chale 22 -10° 21' 59.4" 32° 15' 32.1" Northern 1 1.2 120 0.2 1251 Muchinga 23 -14° 19' 47.8" 29° 36' 17.0" Central 4 6.7 110 0.2 1337 Muketa 24 -14° 52' 26.0" 25° 15' 10.5" Western 2 0.5 202 0.2 1176 Mansa 25 -10° 53' 13.2" 28° 59' 48.8" Luapula 1 0.4 36 0.2 1321 North Western 26 -14° 5' 2.1" 25° 8' 25.6" North Western 1 0.7 238 0.2 1172 Mporokoso 27 -9° 25' 41.0" 30° 1' 51.7" Northern 2 1.5 114 0.2 1478 Mbala 28 -9° 6' 26.8" 31° 33' 46.1" Northern 4 0.7 36 0.2 1586 Mwinilunga 29 -11° 44' 33.9" 24° 55' 34.0" North Western 2 0.7 172 0.3 1518 Chilikita 30 -13° 50' 36.7" 23° 40' 53.6" North Western 2 0.7 175 0.2 1070 Nayumba 31 -12° 57' 52.0" 31° 13' 37.9" Central 7 0.2 132 0.4 1584 DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 22 www.dnvgl.com Figure 3-4 Proposed sites for wind measurement masts DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 23 www.dnvgl.com 4 MEASUREMENT MAST SPECIFICATIONS AND RECOMENDATIONS Robust assessment of the wind resource and meteorological conditions are important stages in the development of calibrating mesoscale wind map. A well-specified, well-managed wind measurement campaign can be crucial to minimizing uncertainties. The following recommendations are based on DNV GL’s extensive experience of wind resource assessments and meteorological conditions analyses. In some cases, IEC requirements for wind turbine power performance measurements, as detailed in [3], are referenced. Although the requirements for wind resource assessments and wind turbine power performance measurements differ in many respects, certain aspects of the requirements presented in [3] are considered to be valid for wind resource assessments. The following sections detail recommendations for equipment and mounting arrangements on the proposed meteorological masts and the associated documentation to ensure full traceability of the measurements. 4.1 Mast Mast type A mast specifically designed for the purpose of wind measurement will be used. The mast will comply with relevant standards regarding expected meteorological conditions at the proposed site, and will have a life expectancy of at least 25 years. The mast type will be a guyed 77 m high galvanized steel lattice tower. The mast will be 3-sided, with a constant face width of 18 or 24 inches, and will include an integrated ladder within the structure diagonal bracing. The mast will also include a fall-arrest cable to provide additional security for personnel climbing the mast. The bottom of the mast will be equipped anti-climb panels. Depending on the region and level of security required, additional security devices, personnel or fencing may be necessary. This will be discussed with Client. The mast will be painted orange and white, as per ICAO regulation, Annex 14, for day-marking purposes. Additional Aviation warning lights will be installed, as detailed in Section 4.3. 4.2 Equipment Wind speed Thies First Class, Windsensor P2546C and NRG Class One cup anemometers will be used to measure horizontal wind speed. All anemometers will be classified as Class 1 according to the requirements of IEC [3] and will be individually calibrated by a MEASNET-approved institution. Parallel anemometers are recommended at the goal post level but also at each measurement height as indicated in Section 4.4.1.1. The inclusion of a redundant anemometer at lower heights shall be discussed with Client. It is DNV GL’s opinion that the installation of a single sensor type on a given met mast introduces an additional level of risk associated with sensor specific flaws or biases that may be inherent in DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 24 www.dnvgl.com the sensor design. An effective way to reduce this risk is to introduce multiple sensor species on the same mast. This approach to sensor installation is designed to yield a more stable measurement campaign that also minimizes the costs associated with possible future maintenance procedures. Furthermore, this practice provides greater clarity in identifying spurious measurements when recorded wind data are subsequently analyzed. Implementing this recommendation will materially reduce sensor specific flaws and protect against measurement biases that can introduce unnecessary error. Several anemometers will be required on each meteorological mast, in order to provide redundancy and investigate the vertical variation of wind speed. Recommendations for the number of anemometers, mounting arrangements and installation heights are detailed in Section 4.4. The power supply for the anemometers is provided by the internal battery power supply within the data logger, detailed in Section 4.3. Wind direction Thies First Class wind vanes will be used to measure wind direction. To provide redundancy, two wind vanes will be installed on each meteorological mast. Recommendations for installation heights are detailed in Section 4.4.1.3. Atmospheric conditions NRG #110S Calibrated temperature sensors with radiation shields, NRG BP20 Calibrated air pressure sensors and NRG RH5X humidity sensors will be deployed on each mast. Sensors to measure atmospheric conditions are useful to support quality assurance checks of the primary wind and direction measurements, and also provide valuable data to assess turbine suitability for future wind farm development. The air pressure sensor will be mounted in a weatherproof box which will be adequately ventilated; this ensures that pressure readings are not influenced by air pressure distribution around the box. Data logger and Communications Campbell Scientific CR1000-XT data loggers will be installed on every mast. These loggers record and store data with a continuous sample rate of 1 Hz, and an averaging interval of 10 minutes will be used. As a minimum, the following statistics will be recorded: • Time stamp; • Mean, standard deviation and maximum wind speed; • Mean and standard deviation wind direction; • Mean and standard deviation temperature, air pressure and relative humidity; and • Power supply voltage. The data logger will be located in a lockable weather-proof housing. Precautions will be undertaken to ensure moisture cannot enter instruments, cabling or the logger housing. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 25 www.dnvgl.com Data loggers will be installed at a height of 3 m, so that access can be gained with a tall ladder; therefore, appropriate measures shall be taken to ensure the security of the data logger and will be discussed with the Client. The data logger will have storage capability for at least 6 months of recorded data, from the addition of a Campbell Scientific NL115 external compact flash data storage. Flash memory cards are used to store data and these should be easy for local staff to retrieve and replace, if necessary. Prior to the site visit, and as indicated in the Client’s request for proposals, a land-based GSM modem and Yagi antenna are planned for data transmission. For remote locations without mobile telephone coverage, satellite communication may be necessary and would be provided with the Hughes BGAN technology. This will be confirmed after the site visit and discussions with the Client. The data logger clock will be set to local standard time in Zambia. The data logger clock will not be changed to reflect local daylight saving (summer) time. The data loggers will allow internet time servers for automatic real-time clock updates. 4.3 Other equipment 4.3.1 Power supply The wind measurement masts will be autonomous. Power for the logger, communications and sensors will be supplied by battery power supply within the data logger and from an external Campbell Scientific BP26 battery, housed in the weatherproof enclosure. The batteries will be charged by an externally-mounted Campbell Scientific MSX20R 20W regulated solar panel, installed on the mast. The system will be configured so that batteries will remain suitably charged, even during winter months, with realistic periods of low light levels. The solar panel will be installed to maximize exposure to the sun. A separate power supply will be installed for the Aviation warning lights, as discussed below. 4.3.2 Aviation warning lights ICAO Annex 14 compliant Aviation warning lights will be installed at the top and mid-point of every mast. Care will be taken to ensure that flow distortion on the wind speed measurements, caused by the aviation warning lights, is minimized. Top Aviation warning lights will be installed 1.5 m below the anemometers at the top of the mast, which are installed on the goal post arrangement. Mid-point lights will be mounted further down the mast and at least 1.5 m vertically from the closest anemometer. The aviation warning lights will be supplied with integrated solar panels and batteries, suitable to provide adequate lighting intensity during low light periods. 4.3.3 Lightning protection Although it is not possible to provide absolute protection from a direct strike, precautions will be taken to protect against lightning damage to the mast and equipment. The sensors will be connected with screened cables that, together with the data logger and mast, will be connected to a local earth. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 26 www.dnvgl.com A lightning rod will be installed at the top of the mast and a protection umbrella of 60° to sensors mounted at the top of the mast will be provided. The lightning rod will be a copper rod. The rod will be fastened to a tower leg at the top, and with a copper wire mechanical attached to the tower. Another copper rod will be driven into the ground near the mast base, and the tower will be clamped to this rod via a copper tail. Due to the attractiveness of exposed bare copper cable to vandalism, DNV GL suggests not installing a bare copper cable downrun on the tower. This will be further discussed with the Client. As the anemometers installed at the top of the mast are the primary instruments on the mast, care will be taken to ensure the flow distortion caused by the lightning rod on the wind speed measurements is minimized. 4.3.4 Bird deterrents Depending on local regulations, mast locations and requirements from Zambia Environmental Management Agency (ZEMA), the installation of bird deterrents on the mast guy wires may be a requirement. Bird deterrents are also commonly referred to as bird deflectors. If necessary, Bird deterrents will be mounted according to the requirements of local standards and environmental best practices. However, care will be taken to ensure that flow distortion on the wind speed measurements, caused by the bird deterrents, is minimized. If regulations allow, bird deterrents will be at least 1.5 m vertically above or 3 m vertically below the closest anemometer. Depending on; the size of the bird deterrents; the magnitude of possible wind flow inclination and the horizontal distance of the bird deterrents from the closest anemometer, these vertical distances may need to be increased. 4.4 Measurement configuration The IEC provides the industry standard for cup anemometer and wind vane mounting arrangements [3], however it is noted that this presents requirements for wind turbine power performance measurements. As a result, the requirements presented in [3] focus on measurements at hub height and in discrete direction sectors. For the assessment of wind resource and meteorological conditions, it is important that measurements are undertaken at a range of heights and that distortion of the wind flow is minimized in all direction sectors, particularly the prevailing wind direction sectors. 4.4.1 Recommended measurement configuration 4.4.1.1 Anemometer mounting arrangements Anemometers installed at the top of a meteorological mast are primarily used as initiation instruments for wind flow modelling. Anemometers installed at lower heights are used to investigate vertical variation of wind speed at the mast location and as reference instruments should the primary anemometers at the mast top fail. Anemometers at the top of the mast will be installed on a goal post arrangement. The horizontal separation will be a minimum of 2 m, and the height above the top of the mast will be a minimum of 3 m, for a total measurement height of 80 m. All anemometers below the goal post will be mounted on slender horizontal booms and vertical arms of circular section. The horizontal booms will be securely attached to the mast and will not flex in the wind. The angle deviation of the anemometer will be less than 2° from vertical. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 27 www.dnvgl.com The maximum center-line flow distortion due to the mast will be kept below 0.5%, as per [3]. In order to achieve this, the length of horizontal the booms will be approximately 2.5 m to 3.5 m. this will depend on the final design and porosity of the masts; details of this calculation are given in [3]. For example, for a square section lattice mast with a thrust coefficient, CT of 0.5, the horizontal booms will ensure that the cups of the anemometer are at least 5.7 mast face widths from the mast. In order to avoid significant flow disturbance at an anemometer due to its own horizontal boom, the vertical arm will ensure that that cups of the anemometer are at least 15 boom diameters above the horizontal boom. In order to further minimize flow disturbance at the anemometers due to the mast, the horizontal booms will be orientated, as much as possible, 90° to the prevailing wind direction. Due to the topography and anchoring challenges, there may some deviations with this best practice. This will be confirmed during the site visits. All anemometers installed in parallel will be installed on horizontal booms orientated at 180° to one another. Where possible, the masts will be installed so that the vertical planes of the guy wires are not orientated in the same directions as the horizontal booms on which the anemometers are installed. An absolute separation distance of 1.5 m between the anemometers and the guy wires will be maintained on all masts. It is recommended that two anemometers are installed in parallel at each measurement height on all masts used for the assessment of wind resource and meteorological conditions. Installing two anemometers in parallel at exactly the same measurement height improves the accuracy of the wind speed measurement at that height and provides redundancy in the event that one of the two anemometers should fail. Flow distortion due to the mast can be further minimized by selecting wind speed data from the two anemometers on a directional basis. Furthermore, issues such as anemometer degradation can be identified with greater accuracy. 4.4.1.2 Wind vane mounting arrangements Although wind direction measurements are less sensitive to flow distortion caused by other objects, the general principles for mounting arrangements of anemometers in Section 4.4.1.1 will also be applied to the mounting arrangements of the wind vanes. In particular, wind vanes will not be installed at the same height as anemometers. The wind vanes will be installed on horizontal booms, with the north of the wind vane (i.e. dead band) aligned along the boom axis, pointing toward (preferably) or away from the mast. This will enable the wind direction offset to be assessed easily from the ground with the aid of a compass once the mast has been installed. The wind direction offset will either be programmed into the data logger or applied during analysis of the data. The alignment of the north of the wind vane shall be documented in the mast installation report, described in Section 4.5. 4.4.1.3 Overall sensor mounting arrangement and heights Recommended installation heights and mounting arrangements for instrumentation on the masts are shown in the Table 4-1 below. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 28 www.dnvgl.com Table 4-1 Instrumentation Summary Height Mounting Instrument Type Manufacturer/Model [m] arrangement 80 MEASNET Calibrated Anemometer Thies First Class Goal post 80 MEASNET Calibrated Anemometer Windsensor P2546C Goal post 77 Wind vane Thies First Class Horizontal boom 77 Calibrated temperature sensor NRG #110S On tower leg 60 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 601 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 58 Wind vane Thies First Class Horizontal boom 40 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 401 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 20 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 201 MEASNET Calibrated Anemometer NRG Class One Horizontal boom 3 Calibrated temperature sensor NRG #110S On tower leg 3 Relative Humidity sensor NRG RH5X On tower leg In Logger Enclosure, 3 Calibrated Barometer sensor NRG BP 20 on tower leg Campbell Scientific CR1000-XT (with Logger and communications In enclosure, on 3 communications equipment to be equipment tower leg determined after site visit) 1 Redundant anemometer to be discussed with Client during in-country workshop The sensor installation heights presented in the table above may be altered for practical reasons or so that sensors are not affected by any objects that may cause flow distortion. It is typically not recommended to install anemometers below 25 m to estimate wind resource at large scale wind turbine hub heights, however, DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 29 www.dnvgl.com wind resource evaluation at a height of 20 m, for small-scale wind development, is one of the current project goals. In areas of significant forestry, it may be necessary to reassess the installation heights of the lowest anemometer to avoid surface effects. For anemometers installed in parallel, the cups of the anemometers shall be at exactly the same measurement height. With the exception of anemometers installed in parallel, a minimum vertical separation distance of 1.5 m will be maintained between all sensors. Exact sensor installation heights to an accuracy of 0.1 m, and the allocation of individual sensor serial numbers to data logger channels and installation heights, will be documented in the mast installation report, described in Section 4.5. For ease of access, pressure and relative humidity sensors will be installed at 3 m agl. Thermometers at the top and ground levels will be installed to allow a more refined analysis of variability in thermal effects. Refer to Figure 4-1 for recommended mast instrumentation schematic configuration. DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 30 www.dnvgl.com Figure 4-1 Recommended mast instrumentation DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 31 www.dnvgl.com 4.5 Documentation For quality and traceability purposes, a detailed mast installation report will be prepared for each individual wind measurement mast. In addition, if there are any changes to the mast and equipment during the measurement period occurs, it will be documented in a mast maintenance log. 4.5.1 Mast installation report The installation report will be prepared for each individual wind measurement mast, which will contain, at a minimum of the following: General information: • Site and mast name; • Mast installation company; • Installation date; • Grid coordinates of mast (including details of coordinate system and datum); • Elevation of mast above sea level; and • Description of surroundings, including distance from mast and height of any significant obstacles or terrain features. Mast and equipment: • Mast type and height; • Lattice mast dimensions; • Exact installation heights above ground level for all sensors; • Dimensions of all horizontal booms and vertical arms installed on the mast, including boom diameters and lengths for all horizontal and vertical members; • Orientations of all horizontal booms, with reference to geographic north; • Orientation of wind vane north for all wind vanes; • Sensor types, serial numbers and corresponding installation heights; • Calibration certificates for all anemometers; and • Data logger type and serial numbers. Data logger configuration: • Data logger program; • Wind vane offsets to geographic north and whether these have been programmed into the data logger; • Details of power supply; • Details of data retrieval; and DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 32 www.dnvgl.com • Details of data logger clock setting. Commissioning: • Data showing first hour of operation after installation and confirmation that it complies with general site observations at the time. Photographs: • Photographs of mast, all booms and all sensors as mounted on the mast; • Panoramic photograph from mast location; and • Photographs of any significant obstacles in the vicinity of the mast. 4.5.2 Maintenance log A maintenance log is a highly useful aid during data analysis. A maintenance log detailing all work carried out on the mast during the measurement campaign will be kept. For each intervention at the mast, the following will be noted: • Date and time of commencement and completion of the intervention at the mast, as recorded by the data logger on the mast (if functional at the commencement of the work); • Reason for the intervention; • Details of work carried out, including a clear description of any changes to equipment or mounting arrangements; and • Serial numbers of any replaced and replacement sensors, including calibration certificates for replacement anemometers. The following will also be documented in the mast history: • Details of changes to the mast surroundings during the measurement campaign (felling of trees, construction of buildings or wind turbines, etc.); and • Details of any periods of missing data (affected sensor, start, end, problem if known). DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 33 www.dnvgl.com 5 REFERENCES [1] Mesoscale Wind Modeling Report #1- Interim wind atlas for Zambia, DNV GL. [2] “Zambia – Atlas of our Changing Environment”, Zambia Environmental Management Agency, 2013. [3] “Wind turbines – Part 12: Power performance measurements of electricity producing wind turbines”, IEC 61400-12:2005 (E). DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 34 www.dnvgl.com APPENDIX A – SPATIAL FEATURES AND CONSTRAINTS MAPPING DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 35 www.dnvgl.com Figure A-1 Preliminary and unvalidated wind speed uncertainty index from [1] DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 36 www.dnvgl.com Figure A-2 Terrain elevation DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 37 www.dnvgl.com Figure A-3 Terrain slopes DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 38 www.dnvgl.com Figure A-4 Aerodynamic roughness from [1] DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 39 www.dnvgl.com Figure A-5 Infrastructure DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 40 www.dnvgl.com Figure A-6 Power generation and transmission DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 41 www.dnvgl.com Figure A-7 Wetlands and Important Bird Areas DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 42 www.dnvgl.com Figure A-8 Environmentally sensitive areas DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 43 www.dnvgl.com Figure A-9 Unofficial land tenure (to be discussed with Client) DNV GL – Document No.: 702833-USSD-R01-D, Issue: D, Status: FINAL Page 44 www.dnvgl.com ABOUT DNV GL Driven by our purpose of safeguarding life, property and the environment, DNV GL enables organizations to advance the safety and sustainability of their business. 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