The Nova Scotia government has approved tidal power Community-Feed-in-Tariffs for Digby Gut and Petit Passage, two passages along the coast of the Bay of Fundy. Digby Gut is a passage connecting the small, enclosed Annapolis Basin to the Bay of Fundy. On the other hand, Petit Passage is a passage between the large, open St. Mary's Bay and the Bay of Fundy. Altering the flow in Digby Gut strongly affects the surrounding tides, while altering the flow in Petit Passage does not. This significantly affects the resource assessment.
Using numerical simulations of the tides and tidal currents through the passages, we examine power extraction from the passages and the resulting impact on the flow. Using theories of power extraction, we examine how the numerical results can be extended to more realistic arrays of instream turbines. The results suggest Digby Gut has a high potential resource (180 MW) but that it will be difficult to realize this resource because of the weak flow in the passage. On the other hand, Petit Passage has a low potential resource (33 MW) but a significant portion of this (10 to 20 MW) could be realized with a reasonably sized turbine array.