Orbital Marine Power is harnessing Scotland's ocean currents for sustainable power. “Turning the tide on climate change.” That’s the motto of Scottish tidal energy company Orbital Marine Power (formerly Scotrenewables Tidal Power). Orbital CEO Andrew Scott is not exaggerating when he says the world’s most powerful turbine is “like nothing the world has ever seen before.” At just over 74 meters long — approximately the size of a Boeing 747 — the 680-ton superstructure has two ginormous blades that slowly churn and generate power. Called the “O2,” this floating power…