Hydropower and Ocean Energy
Part of the Climate Change exhibition.
Part of the Climate Change exhibition.
From rushing rivers to waterfalls to waves breaking on the beach, water energy is all around us. Hydroelectric power plants at dams or alongside rivers use moving water to turn turbines to create electricity. And researchers are currently testing many other ways of tapping into waves, tides, and currents.
Hydroelectric power plants currently provide the world with about 15 percent of its electricity, but there's not much room for big new hydroelectric plants.
Researchers are working on ways to tap into the ocean's energy. Here, linked cylindrical generators, each about the size of a train car, wriggle back and forth in the waves. A resistance system inside each section generates electricity.
Projects that harness the ocean's energy are for the most part experimental, and they are unlikely to provide a substantial portion of Earth's electricity over the next few decades. But one of the simplest methods has been around for decades: since 1984, the Annapolis Tidal Generating Station in Nova Scotia has opened gates in a dam to allow a basin to fill with water during high tide. As the tide recedes, the outgoing water flows through turbines, generating electricity for thousands of local homes and businesses.