The milestone is doubly ­important for Marine Current Turbines (MCT), which will be debuting an ­innovative three-headed, multi-megawatt version of its SeaGen concept in the ferocious, rubble-laden currents of the Minas Passage.

MCT’s machine will face the challenge alongside those of Euro­pean tidal-technology­ competitors ­Atlantis ­Resources, ­Alstom and Open­Hydro.

Some 14 billion tonnes of Atlantic Ocean surges through the narrows twice a day at speeds peaking at 5.5