Blue energy—Sustainable power from water

Energy is the most fundamental driving force for global development and economic growth, and the foundation on which human civilization builds. However, the extraction and use of traditional energy often come with environmental pollution and ecological damage. With the limited resources of fossil energy, such as oil, coal, and gas, developing renewable green energy is desperately important for protecting the ecological environment, achieving global sustainable development and simultaneously realizing zero carbon emissions. Here, the most important component of green energy, blue energy, is introduced, which refers to all kind energy related to kinetic and potential energy from water, including hydropower, ocean tide and wave energy, and offshore energy including offshore wind energy, offshore solar energy, and their hybrid energy. The current status and development trends of blue energy are presented, and a novel blue energy harvesting technology, triboelectric nanogenerator (TENG), is brief presented.