riverturbines




A consortium of private enterprise, government and educators has formed the Cornwall Ontario River Energy (CORE) project to determine whether a free-flow underwater turbine, shown here being placed into New York's East River, is feasible in the St. Lawrence River. If the experiment works out, Cornwall's twist on tidal power could generate up to 5 megawatts of electricity, enough to power about 5,000 homes, according to Verdant Power. (Photo courtesy Verdant Power)


Bold experiment tests underwater turbines in Cornwall
in new twist on tidal power in the St. Lawrence River


News Archive BY GARY MAY
It all began with an orange tossed into the St. Lawrence River. Patrick Finucan and his friend, Blayne Mackey, watched from the riverbank at Cornwall as the orange floated quickly downstream. Clearly, it was a powerful current.  

Mackey had been reading on the Internet about a company called Verdant Power that was experimenting with using the force of the tides off the coast of the United States to generate electricity. What might Verdant Power think about all that potential energy passing by Cornwall — beneath the surface of the river?  

They got in touch with Verdant and before they knew it, a multimillion-dollar experiment was under way to harness the underwater force of one of Canada’s most historic and economically important rivers.  

If all goes well, Verdant will soon be placing underwater “windmills” into the river off the shoreline at Cornwall and eventually generating 5.0 megawatts of electricity, enough to operate about 5,000 homes, and all without the construction of a single new dam.  

“To have people focus on Cornwall and this experiment — wouldn’t that be neat?” Finucan tells MyNewWaterfrontHome.Com. “It would be a dream come true.”  

Hydro One has been using the river to produce electrical power above the surface for years. Now, a consortium of private enterprise, government and educators has formed the Cornwall Ontario River Energy (CORE) project to determine whether something called a free-flow underwater turbine is feasible here.  

Power without building new dams

Free-flow turbines create power from water without the necessity of building more dams. Coincidentally, the experiment is taking place in the shadow of the immense Moses-Saunders hydroelectric dam, built as part of the 1950s-era St. Lawrence Seaway project.  

The free-flow concept works much like a wind turbine, except the blades are moved by the underwater current, rather than wind. The turbine blades rotate slowly — about 32 revolutions per minute — allowing fish to pass through without harm, and, hopefully, without any unnatural churning up of the riverbed.   The blades are placed sufficiently deep — they’d never come less than five metres from the surface — so as not to interfere with pleasure craft, and they’ll be put well outside the Seaway shipping lanes, which run south of Cornwall Island, home of an Indian reserve.  

The river project is a variation on tidal power, the widespread use of which has long been a dream of mankind. The first proposal to harness the tides in the Bay of Fundy was put forth in 1910, although simple variations in the use of tidal power date back to Roman times. Verdant Power has experimental tidal projects under way in New York’s East River, a tidal estuary that connects Long Island Sound with the Atlantic, and Puget Sound in Washington state.  

The CORE partners include Verdant, the Canadian and Ontario governments, the Mohawk Council of the Akwesasne, the City of Cornwall and the St. Lawrence River Institute of Environmental Sciences.  

Finucan is executive director of the St. Lawrence River Institute and the retired director of the Cornwall campus of St. Lawrence College. Now he’s also the CORE project’s spokesman and a very enthusiastic proponent.  

He says CORE is in its first phase right now. This involves obtaining permits, then, by mid-October, placing an acoustic doppler current profiler (ADCP) and video camera beneath the surface to monitor the impact on wildlife.  

Environmental impact to be watched closely

If all goes well, a non-working model turbine would be placed on the floor of the river, hopefully by April 2011. Then by late summer, one or two real turbines would be introduced. While initial power generation would be small, the goal is to eventually create about 3.5 to five megawatts of power.  

A similar experiment involving another company is planned for the Montreal area of the St. Lawrence River.  

All along the way, says Finucan, the impact of the equipment will be closely monitored. He says environmental impact is a significant concern among First Nations and government authorities, and one that will need to be addressed before they proceed to each further step in the process.  

He points to the fact the plan is to set the apparatus on the bottom of the river, which means no drilling will be required to fasten it to the bedrock. That means less intrusion on the environment.  

The whole idea got put in motion because Finucan headed an alternative energy committee that was, a few years ago, looking at prospective projects for the Cornwall area. His old friend, Blayne Mackey said to him: “Pat, look at the river.”  

That’s when Mackey went on the Internet and found Verdant Power. He wrote to the company with an inquiry. Then the friends tossed the orange into the river to see how quickly it would travel. “It was surprising to see how fast it moved,” says Finucan.  

More scientific measurements of the river current were taken and Verdant decided the Cornwall men were on to something. Grants were obtained from the federal and Ontario governments and experiments were planned.  

If the underwater turbine plan proves successful, it could spell significant benefits for Cornwall’s economy. For example, St. Lawrence College is prepared to introduce a training program for workers in this emerging alternative energy field.  

Verdant has estimated that there is enough potential power in the water currents of Canada’s tides, rivers and man-made channels to generate 15,000 megawatts of electricity. That’s the equivalent of about 15 large coal power plants.  

Tests with the underwater turbines in other locations have not come without glitches. In New York’s East River, the blades cracked because the tidal current was stronger than anticipated.  

The start of green energy industry

“Every single rotor broke in the same spot and caused a cascading effect,” explains Verdant founder and president Trey Taylor. “We learned that we had arrayed them wrong in the water.”  

Taylor told MyNewWaterfrontHome.com that by positioning the turbines downstream from the existing hydroelectric dam, there is also less danger of debris interfering with their operation.  

There are some differences between the St. Lawrence project and the tidal project. For example, the St. Lawrence River current always flows in the same direction, while a tide reverses itself as it goes in and out.  

Cornwall has received a lot of negative publicity in the past from the polluting industries that once existed in the area. But with most of those industries now shut and replaced with cleaner alternatives, Ontario government environmental figures show Cornwall is one of the cleanest communities in the province. Underwater turbines could be catalysts for even more green energy alternatives for the area, Finucan hopes.  

As more of the world’s traditional fossil fuels are burned off and concern grows for the fallout from mining oil from Alberta’s tar sands and offshore wells in places such as the Gulf of Mexico, we’re looking ever farther afield for environmentally friendly ways to generate power. More and more of our energy is produced from the sun and the wind. Sometimes, it seems everything old can be made new again.  

Hydroelectric water power remains an important source of energy for our society. But if that same water can be put to use from a different angle, so much the better. Many sets of eyes are keeping a close watch on the Cornwall underwater experiment, all because a couple of men tossed an orange into the St. Lawrence River.  

MyNewWaterfrontHome.com — September 2010