Hydro-Quebec's 20-year deal to provide Massachusetts with electricity will help keep utility rates low for Quebecers for years to come according to the provincial government.

On Thursday the U.S. State approved the Northern Pass deal, wherein Hydro-Quebec and its U.S. partner, Eversource, will provide Massachusetts with up to 9.45 terawatt-hours of electricity every year.

It could generate up to $500 million in revenue for the Crown utility every year, which Natural Resources Minister Pierre Moreau said would be a boon to the province's income.

"It will help Hydro-Quebec not reduce, but maintain low rates for Quebecers. There is no direct link to that but it's good news to increase the revenue of the government-owned company," said Moreau.

Under the plan, which still has to be approved by Canada's National Energy Board and the state of New Hampshire, Hydro-Quebec will build high-power transmission lines to the border, at which point Eversource will run lines through New Hampshire.

“On both sides of the border we'll see benefits from that deal,” said Hydro-Quebec CEO Eric Martel, adding that thanks to stable energy prices, the venture will profitable.

Hydro officials said the province is able to export about 16 per cent of its electricity production because overall province-wide consumption has decreased over the past decade, while the utility continues to build dams to increase capacity.

Hydro-Quebec said the cost of producing electricity is easy to control and has remained consistent with the level of inflation, with the advantage of not burning material and producing greenhouse gases.

“We know it went up by inflation pretty much perfectly since 1963 and we have the knowledge and we understand exactly what our cost will be in 5, 10, 20 years, we can even go 40 years,” said Martel.

Massachusetts, like other states, is looking to reduce its carbon footprint. It issued a call for tenders for utilities that could produce electricity from renewable sources.

“We need more connectivity, more capacity with New York,” said Moreau.

As profitable as the deal is, the money generated will not be used to reduce rates in Quebec; they remain the lowest in North America, said the energy minister.

“It will help Hydro-Quebec not reduce, but maintain low rates for Quebecers, but there's no direct link to that,” he said.