While tidal energy was once cost prohibitive due to the difficulty of installation and maintenance, recent technological advancements have allowed tidal energy to become something financially and logistically possible. There are two methods of generating tidal energy - tidal stream generators, which are turbines similar to those used with wind power and tidal barrage, which use dams and the change of tide to generate power and a third method, dynamic tidal power, is currently in the development phase but is as yet untried.
The installation of tidal energy shouldn't be any more complex than shallow offshore oil drilling. Tidal energy is a vast resource near the shores of Earth's oceans. Installing tidal turbines should be fairly easy as the shores are shallow and can be put in during low tide instead of high tide. The trick is making sure the ocean's life forms aren't unduly affected by the tidal turbines, just like birds can be killed by wind turbines.