Nova Scotia's consumer advocate is asking the Utility and Review Board to reject the Maritime Link deal as currently proposed by Nova Scotia Power's parent company, Emera Inc.

John Merrick said the $1.5-billion subsea cable known as the Maritime Link — part of the Muskrat Falls hydroelectric proposal — benefits Emera but leaves ratepayers at risk of paying too much for electricity.

"Ultimately our position is that the application should be turned down. There are downsides to this," he told CBC News.

"In our view, the project would be a more expensive source of energy in the long term than if we remain flexible, making decisions as we need to make them on an incremental basis depending on what the changing circumstances may be over the next 35 years."

The Utility and Review Board's public hearing on Maritime Link begin next week and opening statements have been filed by many intervenors.

Some of those intervenors say ratepayers should not pay the $1.5-billion construction cost because Emera Inc. has failed to prove the Maritime Link will provide the lowest cost, long-term source of renewable energy.

The utility's business case relies on buying a large volume of extra electricity from Labrador or another supplier that has not been guaranteed.

Others opposed to the project include lawyers representing small and large businesses, a group known as the Lower Power Rates Alliance Nova Scotia, the Canadian Wind Energy Association and the consulting firm hired by the regulator to review the project.

The province of Nova Scotia and Emera have asked for the project to be approved.

Emera Inc. is a minority partner in the Muskrat Falls project and is responsible for the Maritime Link, which may see as much as 40 per cent of the electricity from the 824-megawatt project moved to Cape Breton by subsea cables.