Re-Evaluating the Sustainability of Energy Systems : The Nexus of Energy, Water, and Land-Use

Scenarios for global developments typically point to a sharp increase in demand for energy as well as for water and land. These developments have a starting point where global ecosystems are already being exploited unsustainably. This has implications for energy systems, which can be designed as more or less water and land-use intensive. However, evaluating the sustainability of energy systems commonly do not take water and land-use systems into account. This presents a problem as these three systems—energy, water, land—are intrinsically linked, which provides both barriers and opportunities for these systems' individual as well as collective sustainability. More comprehensive evaluations of energy systems that acknowledge the system interlinkages are therefore needed. This has become known as applying a nexus approach. The idea behind the nexus approach is to increase system synergies and resilience through jointly analyzing ecosystem capacities, drivers for resource use, development objectives, capacities to manage linked systems, and the need for new knowledge. This provides a comprehensive perspective on the restrictions and freedom we have in governing, designing, and using the social, technical, and ecological systems. The article thus presents a nexus approach and provides an understanding of challenges for the sustainability of energy systems from a broad system perspective.