electrical energy generated by harnessing the up-and-down motion of ocean waves. Wave power is typically produced by floating turbine platforms. However, it can be generated by exploiting the changes in air pressure occurring in wave-capture chambers that face the sea. The areas of greatest potential for wave energy development are in the latitudes with the highest winds (latitudes 40°–60° N and S) on the eastern shores of the world's oceans. For instance, the world's first operational wind-power generator is located off the coast of Aguçadora, Portugal, producing as much as 2.25 megawatts from three huge jointed tubes that float on the surface of the Atlantic Ocean; individual power generators are located at the tubes' joints and activated by wave motion. In addition, a large potential for wave power systems exists in the British Isles and the Pacific Northwest of the United States. In theory, wave energy can produce nearly 2,000 terawatt-hours per year—that is, approximately 10 percent of global electricity production.