The tide moves a huge amount of water twice each day, and harnessing it could provide a great deal of energy. Ocean currents are found along coastlines beneath the oceans surface at depths of 80 to 230 feet (25 to 70 meters) and with flow rates of 5 to 10 feet per second (two to three meters per second). Horizontal or vertical axis turbines, much like underwater wind turbines, can be used to capture the energy from ocean currents or tidal flows. They can be installed so as not to interfere with fishing or the passage of vessels. The slow speed of the turbines does not interfere with aquatic life.