Physics World  March 3, 2020 Most approaches to harvesting mechanical energy from ocean waves rely on finding a way to move a conducting wire through a magnetic field to generate electricity. Researchers at Georgia Institute of Technology designed triboelectric nanogenerators (TENGs) in small plastic spheres, about the size of oranges, that float in water. As the waves jostle the sphere, material inside bumps against the outer shell, generating charges. Th charges then flow through an attached wire. In lab tests each sphere could generate about 10 mW of power enough for powering small devices such as sensors on buoys used […]