A shapefile containing the postcode areas supplied by secondary substations. The dataset is generalised using our GIS customer connectivity model. Each Secondary Substation's connected LV Network is traced out to its electrical extents, including all connected customers. Using the geographic position of customer connections and key network points of both the Substation being traced and surrounding Substation's network, a Voronoi diagram is created. Each Voronoi polygon that intersects with the traced network is joined together to produce a single polygon, depicting the Supply Zone. This dataset is redacted in that any secondary sites with less than five customers will not be included to protect privacy.
