The 40% target is part of Nova Scotia's plan to move from a heavy dependence on coal generation to a more balanced supply. "We had, just a few years ago, upwards of 80% of our electricity coming from coal and ugly things like petcoke," says Bruce Cameron, director of policy at the Department of Energy. "We will, with a combination of natural gas and renewable energy, cut that in half by the end of this decade."
The province already has a legally binding renewable-energy target of 25% by 2015, and Cameron sees wind as a key player in getting there. Nova Scotia currently has 285MW of installed wind and expects to increase that to about 500MW by 2015. On a system with a peak winter load of around 2.2GW that can drop by as much as two thirds during spring and summer, the province will "hit a bit of a plateau for wind" without more responsive generation sources to help balance its variation in output, Cameron says.
A planned new 500MW high-voltage direct-current transmission interconnection with Newfoundland, dubbed the Maritime Link, will provide Nova Scotia with significant technical capability for balancing wind, says Bill Marshall, president of WKM Energy Consultants. The 180-kilometre undersea cable will bring power from the 800MW first phase of the Lower Churchill hydro project, scheduled to come online in 2017.
Co-operation is key
Nova Scotia is making a 20% investment in the C$6.2 billion project, and in return gets 170MW of hydro output a year, with an option for 330MW more. The government has introduced legislation to allow the power to be used to meet its renewable energy goals. The 170MW translates into one terrawatt hour a year, slightly more than half of what is needed to go from the 25% mark to the 40% target.
"In that world, we're confident the rest can be made up by any one of a number of sources in the province, including more wind and biomass," says Cameron.
Marshall expects the injection of Lower Churchill power will also help push the Maritime provinces - New Brunswick, Nova Scotia, and Prince Edward Island - towards greater regional co-operation, something the wind industry has long argued is needed in order for the region to fully exploit its wind resource. Nova Scotia and New Brunswick operate separate electricity systems and the jurisdictional split limits how much wind energy each can manage on its own.
"I believe that eventually we will get to one balancing area and that the Lower Churchill project is a catalyst to get us there," says Marshall. Once this happens, integrating it with existing hydro will provide a good resource to balance wind throughout the Maritimes, he adds.
That could help the region, which has a strong resource but limited domestic demand, move forward on its oft-repeated desire to tap into markets for green power in the north-eastern US.