The ocean tides are a powerful but underutilized energy source. Though tidal power does not provide a significant part of the world’s electricity, it has enormous potential as a source of renewable energy.

Like solar and wind energy, tides provide an inexhaustible source of clean energy. Tides have the advantage of being far more consistent and predictable than the wind or sun, following a regular schedule based on the rotation of the Earth. They can supply continuous power regardless of weather conditions.

The two main methods of generating tidal power are tidal barrage and tidal stream technology. A tidal barrage is a large, dam-like structure that traps rising waters on one side and releases it through a turbine, which spins to generate electricity. Tidal streams resemble underwater wind turbines, harnessing the kinetic energy of the fast-flowing currents tides create.

Tidal barrages are most effective in areas where there is a large tidal range (the vertical difference between the high and low tides). With a tidal range of 15 metres, Nova Scotia’s Bay of Fundy is considered one of the best potential sites for tidal power in North America. Other candidates for tidal barrage technology in Canada include Ungava Bay in Quebec, the St. Lawrence Seaway, and various locations along the coast of British Columbia.

Tidal streams are a new entrant in the world of renewable energy. The first tidal stream turbines were developed just ten years ago, and there is still no consensus on the optimal design. Much like wind turbines 20 years ago, tidal stream turbines will likely become more affordable and efficient as technology improves.

Many coastal countries are embracing tidal technology as part of their renewable energy strategy. The world’s largest tidal power plant was constructed in South Korea in 2011, and a company in Scotland is in the process of building an even larger plant. When complete, the MayGen project will generate around 300 MW of electricity.

In Canada, the Bay of Fundy is becoming a tidal technology hub, with developers and utilities planting roots in the area to build a Canadian tidal power industry.