Nova Scotia Power says it's on track to reach its mandated target of 40 per cent renewable energy by 2020 after a new usage record was set in 2016.

Last year, 28 per cent of the electricity used by Nova Scotians came from renewable resources, the company said in a news release Friday, highlighting numbers first made public in February.

The current legislated requirement is 25 per cent. That rises to 40 per cent by 2020.

Nova Scotia Power spokesperson David Rodenhiser said tapping into the Muskrat Falls hydroelectric project in Labrador three years from now will give the the company the push it needs to reach 40 per cent.

The project has been beset by delays and ballooning costs, but Rodenhiser said the current timeline of mid-2020 still works for Nova Scotia.

Already reaching Paris targets

"When 2020 comes around, we'll have access to a great hydroelectric resource there that'll help get us to that 40 per cent requirement for renewable energy," he said.

In raw numbers, Nova Scotia Power emitted 10.6 million tonnes of greenhouse gas-equivalent emissions in 2005, and 7.1 million tonnes in 2016.

"We're actually leading Canada on carbon reduction, with a more than 30 per cent reduction from 2005 levels, which puts us already as having achieved the COP21 target [set in Paris in 2015] of a 30 per cent reduction by 2030," Rodenhiser said.

These wind turbines shown in 2012 in Amherst are some of the 300 or so turbines scattered throughout the province. (Paul Darrow/Reuters)

There have been two big changes in Nova Scotia's electricity generation over the past decade: wind has risen from one per cent of electricity by source in 2007 to 17 per cent last year, while coal and petroleum coke have dropped from 76 per cent to 55 per cent over the same time period. (Hydro and tidal, biomass and imports have all seen incremental percentage increases, while natural gas and oil have held steady.)

There are now more than 300 wind turbines throughout Nova Scotia, but Rodenhiser said the more traditional means of power generation are needed to fill in the gaps when the wind drops.

"That's what the folks at our coal plants and at our natural gas plant at Tufts Cove in Dartmouth have been figuring out how to do with a thermal fleet of plants that weren't designed to be brought up and down, but they've figured out how to do it in a way that allows to integrate all the wind onto the grid," he said.

Impressive, but at a cost

Larry Hughes, a professor at Dalhousie University who closely follows energy security and energy policy, said the increase in renewables by percentage is "very impressive" but comes with a few caveats.

"The thing to keep in the back of the mind, though: [renewable energy] was essentially forced upon the company through legislation and much of this has been paid for by Nova Scotians," he said. "Electricity rates have gone up."

Hughes said fluctuating coal prices have played a role, but that the 62 per cent increase in residential electricity prices since 2005 is due in part to the increase in renewables.

Rodenhiser said the province went through a period when renewable energy raised prices, but that the costs have been stable the last two years and are expected to rise less than inflation for the next couple of years.

Hughes also noted that Nova Scotia Power has been reaching its targets in part because of the closure of a number of pulp and paper mills earlier this decade.

"It was easily about 20 per cent of Nova Scotia Power's demand," he said.

Hughes said it's "quite probable" that Nova Scotia Power and the province will meet their renewable energy targets, though there are some potential roadblocks, including if Muskrat Falls is delayed again or if climate change leads to droughts or changing winds.