Never underestimate the power of the seas, especially as you dive beneath the surface. There you can find currents with more power than multiple nuclear power plants can produce. Researchers at Worcester Polytechnic Institute have been working on underwater kites that could potentially tap into those currents, similar to how wind turbines tap into the wind.
The researchers have recently received a $300,000 grant from NSF to develop systems to harness the power of tidal flows. Previously the researchers had researched low-cost kites for harnessing wind power (a project also funded by the NSF, along with the EPA) and now they are looking to adapt their models for use underwater. Using those models they will determine the best design for the kites, as well as the optimal placement of the turbines that will actually generate the electricity.
This is not the first endeavor to capture the power of tidal flows, but many of the previous attempts relied on stationary turbines. The mobility of the envisioned kite system however, could increase energy output significantly, while also being smaller and cheaper to use.
Source: Worcester Polytechnic Institute