Marine renewable energy (MRE) projects and associated studies on environmental effects mainly exist in temperate regions. As MRE develops in tropical and subtropical regions, there is a need to assess its potential environmental effects. In those regions, all types of MRE resources are available: wave energy, tidal energy, ocean current energy, ocean thermal energy conversion (OTEC), and salinity gradient energy. OTEC uses temperature gradients between warm surface waters and cold deep waters to produce energy, a unique feature of tropical and subtropical regions. Salinity gradient energy uses the differences in salinity between freshwater and seawater; the greatest potentials are found along warmer coastlines. Although MRE resources exist, prior and existing MRE projects are relatively sparse and most target wave energy resources. Because of the unique marine ecosystems (e.g., coral reefs, mangroves) of tropical and subtropical regions that support multiple ecosystem services (e.g., tourism, fisheries), MRE development may present additional risks compared to temperate regions.
This Short Science Summary was developed based on the OES-Environmental 2024 State of the Science Report: Environmental Effects of Marine Renewable Energy Development Around the World, specifically Chapter 10: Environmental Effects of Marine Renewable Energy in Tropical and Subtropical Ecosystems.