VICTORIA — The fast-moving tides and deep waters near Victoria were the backdrop for Prime Minister Stephen Harper's January announcement if $1.5-billion in spending over 10 years to boost Canada's supply of green energy.
Mr. Harper chose Race Rocks Island -- 10 nautical miles southwest of Victoria -- because it is home to a made-in-B.C. tidal-energy experiment.
Last summer, Vancouver-based Clean Current Power Systems, which received funds from Alberta's energy giant EnCana and the federal government, installed a tidal turbine generator near Race Rocks.
It's a harsh work environment. Salt water corrodes the metal equipment, and the tides flow like a fast-moving river, which is more taxing on the generator than a slower current.
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Other challenges have surfaced.
Huge capital expenditures, environmental assessments, B.C. Hydro's co-operation and consumers willing to pay more are required for the project to be a success.
"It's definitely not going to be easy," said Glen Darou, president of Clean Current. "It comes down to how badly do we want it."
Tidal generators are anchored to the ocean floor and work like windmills. The tide flows in and turns the blades, which have a magnet attached. The magnet passes by coils, creating electricity that powers a lighthouse and a couple of buildings on the island.
The lessons learned from the prototype, which cost $7-million to build and has developed problems with its bearings, will be used in the planning of a larger, commercial generator, said Mr. Darou, a former chief financial officer at Shell Canada and Cominco.
If 20 large units were placed near Race Rocks, they would produce about 75 million kilowatt hours of energy. That's enough to supply 7,500 average B.C. homes.
In Discovery Passage, near Campbell River, the tides are also fast, and there is underwater space for up to 200 generators. Each one would be almost as tall as B.C.'s Legislative Building.
Mr. Darou envisions a wall of the 19-metre-blade units, silently working. The large tidal farm could produce 850 million kilowatt hours of energy -- enough for 85,000 average homes.
By comparison, B.C. Hydro's largest hydroelectric facility, the W.A.C. Bennett dam (one of 30 hydroelectric sites in the province) can generate 2.73 million kilowatts of power at any one time.
The Discovery Passage project would cost about $800-million and take three years to complete. To be cost-effective, a large-scale installation is necessary.
Mr. Darou doesn't think British Columbians are ready to finance the expensive project, or for the higher hydro bills.
He optimistically estimates a rate of about eight cents per kilowatt hour for tidal power, which is 33 per cent more than the six cents per kilowatt hour B.C. Hydro customers pay now.
University of Victoria ocean physics professor Chris Garrett said British Columbians shouldn't pin their hopes on tidal power.
He cautions that predictions of the amount of energy that can be generated are based on optimum conditions, and thus are exaggerated. The average production at a tidal farm could be as little as 20 per cent of the estimate.
In 2005, B.C. Hydro assessed tidal power and concluded that it wasn't commercially feasible.
But now that the gap between supply and demand is growing, B.C. Hydro is considering alternative energies. In December, it will accept bids for projects from both "proven" and "innovative" technologies.
B.C.'s Energy Plan states that new electricity generation projects must have zero net greenhouse emissions, which tidal power can achieve.
B.C. Energy Minister Richard Neufeld said tidal power is in its infancy. It will be part of the province's energy mix once its price is comparable to hydroelectric.
When the cost of hydroelectricity rises by 2 per cent, Mr. Neufeld said his office receives thousands of complaint letters. Keeping voters happy while creating 30,000 gigawatts of energy over the next 25 years will be a balancing act, he said.
Dr. Garrett would be delighted if tidal power "would save the world," but as a "green" energy source, its value is a tad tarnished.
During his 40-year career, Dr. Garrett has studied the effect of tidal generators on the environment, and when many generators are installed, they exert a drag on the water and slow its flow.
Currents and tides can be significantly altered, he said.
And even though they are anchored 15 metres deep or more, generators can prevent the passage of large ships and fish, and can kill marine mammals.
More collaboration between engineers and oceanographers is required when tidal projects are being considered, Dr. Garrett said.
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