Wave Power

There are prototype experiments going on right now in India. The devices are called Anacondas. you can read the entire article here.

Anaconda tubes are closed systems filled with water placed 40 to 100 meters below the surface of the ocean. The tubes — estimated at 200 meters long and 7 meters in diameter in their production form — are oriented so waves hit the end of the tubes, generating bulge waves that travel along the tube at the same speed as the waves that originated them.

The external wave squeezes the flexible tube, causing the internal bulge wave to grow bigger. The bulge wave eventually hits a turbine at the very end of the tube, generating electricity that is fed to a power system via a cable.