One we've completely missed is Minesto, which is taking a very different and remarkably dynamic approach compared to most. Where devices like Orbital's O2 tidal turbine more or less just sit there in the water harvesting energy from tidal currents, Minesto's Dragon series are anchored to the sea bed, and fly around like kites, treating the currents like wind. Minesto's Deep Green technology ?" Unlocking renewable baseload power Just as land-based wind energy kites fly in figure 8 patterns to accelerate themselves faster than the wind, so does the Dragon underwater. This, says Minesto, lets the Dragon pull more energy from a given tidal current than other designs ?" and it also changes the economic equations for relevant sites, making slower tidal flows worth exploiting.