Fig. 6. A conceptual diagram of the relative potential for improving the sustainability of hydropower projects at various spatial scales and stages of development. The y-axis represents the potential incremental improvement in environmental sustainability for a given energy generation target. The greatest potential improvement occurs during initial site selection and the potential for improvement is lowest once a project is already constructed. A regional or basin-scale approach (solid line) provides a greater set of potential solutions, and thus greater potential sustainability, than a single-project approach. By adopting a basin-scale approach, the Penobscot Project moved from position a to position b on this conceptual diagram.
Fig. 6