Digitalization and real-time control to mitigate environmental impacts of artificial barriers in rivers: Focus on hydropower systems and European priorities

Hydropower globally represents the main source of renewable energy, and provides several benefits, e.g., water storage and flexibility; on the other hand, it may cause significant impacts on the environment. Hence sustainable hydropower needs to achieve a balance between electricity generation, impacts on ecosystems and benefits on society, supporting the achievement of the Green Deal targets. The implementation of digital, information, communication and control (DICC) technologies is emerging as an effective strategy to support such a trade-off, especially in the European Union (EU), supporting both the green and the digital transitions. In this study, we show how DICC can foster the environmental integration of hydropower into the following Earth spheres: hydrosphere (e.g., water quality and quantity, hydropeaking, environmental flow), biosphere (e.g., riparian vegetation, fish habitat and migration), atmosphere (methane emissions and evaporation from reservoirs) and lithosphere (sediment management, seepages), while mitigating impacts coming from the anthroposphere (e.g., combined sewer overflows, chemicals, plastics and microplastics). Results include the main DICC applications, case studies, challenges, Technology Readiness Level (TRL), limitations and transversal benefits for energy generation and predictive Operation and Maintenance (O&M). The priorities for the European Union are also discussed. Although the focus was on hydropower, analogous considerations are valid for any artificial barrier and civil structure which interferes with freshwater systems.