Least-cost path analysis and multi-criteria assessment for routing electricity transmission lines

The classical approach for transmission line (TL) routing based on paper maps, aerial photographs and field visits can generate inconsistent results, besides being a time consuming and intensive labour activity. The application of methodologies based on geographic information system (GIS) combined with multi-criteria assessment (MCA) methods can generate time and cost savings on the planning step. However, this methodology still must be better assessed for its applicability and improvements can be made. Therefore, this study aims at verifying the applicability of a GIS methodology for TL routing using analytic hierarchy process (AHP) for weighting criteria. In addition, the effectiveness of AHP method is evaluated comparing the previously attained results with a route modelled using monetary values to weight the criteria. To achieve the objectives, the methodology is applied for an area in the northern region of Brazil (state of Para) where a 230 kV TL is already implemented: the TL Vila do Conde-Castanhal. As a result, routes with lower length and lower total cost than the implemented TL were obtained, which suggest the potential benefits of applying the proposed methodology compared with traditional route planning, which does not use quantitative MCA and more advanced GIS tools.