Richard Karsten

Tidal Power from the Bay of Fundy

Richard Karsten
Acadia University

The Bay of Fundy has the world's highest tides. In particular, the Minas Basin has tides with a range of over 12m. The energy inherent in these tides has encouraged the discussion of tidally generated electric power in the region for nearly one hundred years. In the past, the economical and ecological costs of large scale power extraction were always considered too high. The recent development of in-stream tidal turbines appears to address both these issues. The Minas Passage, which connects Minas Basin to the Bay of Fundy and has mean tidal currents of over 3m/s, is the ideal location for tidal turbines. In this talk we examine the potential power that could be extracted from Minas Passage and the effect this power would have on the surrounding environment.

A simple mathematical model is used to predict the effect of turbine drag on the flow through the Minas Passage and the tidal amplitude in the Minas Basin. The theory is compared to two dimensional, finite element numerical simulations of the Bay of Fundy-Gulf of Maine system. Together, they suggest that a maximum of 7 GW of power can be extracted by turbines. (For comparison, a typical nuclear power plant would produce 1 to 2 GW.) The simulations also show that any power extraction in Minas Passage pushes the Gulf of Maine-Bay of Fundy system closer to resonance with the forcing tides resulting in increased tidal amplitudes throughout the Gulf of Maine. While extraction of the maximum power will result in significant changes, over 2.5 GW of power can be extracted with less than a 5% change in the tidal amplitude at any location. Finally, we examine how isolated turbines and turbine fences might be best located in the Minas Passage by examining the fluid dynamics of flow past a turbine.