The mighty St. Lawrence River will soon be home to a power-generating pilot project that could one day churn in rivers across Canada.

The company that builds the underwater river turbines says the test phase will start off small, producing enough energy to power 750 homes.

"It's a bit like a windmill sitting on the bed of the river, so the water (goes) through the turbine and then it produces electricity because of the movement of the turbine," explained Georges Dick, president of RSW Inc.

Dick says the technology has huge potential in Canada's biggest waterways, including the Mackenzie, Peace and Fraser rivers.

"It can be sustainable with reasonable costs, so it's part of the solution to reduce our greenhouse gases," said Federal Natural Resources Minister Christian Paradis.

The federal and provincial governments are funding one-third of the $18 million project.

Paradis says it's a low-cost, renewable energy source that will create hundreds of jobs.

Paradis insists the spinning blades inside the three-metre-high turbines will not have an impact on underwater wildlife.

Energy expert Philip Raphals of energy research group the Helios Centre said previous studies have shown the impact is minor.

"There are potentially issues where you're getting into fish and underwater life, but presumably those will be studied and so far similar technolgies have not shown any serious problems," Raphals said.

The pilot project will see two turbines plunked into water off the shores of Montreal in the coming weeks.

Quebec hopes to eventually use the technology to power its northern communities, which rely heavily on polluting diesel-fuelled generators.

"The diesel energy is not appropriate in this environmental context, and this project proposes a solution for the challenges for the Inuit communities," said Quebec Resources Minister Nathalie Normandeau.

With a report from The Canadian Press