Scientists at MIT have suggested extending transmission capacity between the electricity systems of the northeastern U.S. and the Canadian province of Quebec to enable bi-directional power flows between the two. At present, excess power only flows from Canada to key U.S. markets in New England and New York state.
Extending cross-border links and enabling two-way power flows would mean Quebec’s hydropower reservoirs could provide grid balancing to the two U.S. markets and the storage potential north of the border could drive more solar and wind deployment south of the line, according to the MIT researchers.
“In many scenarios, the complementary service provided by additional transmission makes it economical to expand wind and solar PV capacity even further, saving on the cost of more expensive alternatives such as gas generation,” the scientists wrote in the MIT study Two-Way Trade in Green Electrons: Deep Decarbonization of the Northeastern U.S. and the Role of Canadian Hydropower.
Quebec has around 40 GW of installed hydropower generation capacity, enough to meet 90% of local demand in the province. Around 36 GW is operated by state-owned utility Hydro-Quebec.
The MIT group predicted New England and New York would import less power from Canada if Quebec were able to import low-priced clean energy from the U.S. regions at times of peak generation. During such periods, the hydropower facilities of Quebec could reduce output and let reservoir levels rise before ramping up generation and exporting hydropower to the U.S. markets when less solar and wind power was being generated south of the border.
“As northeastern [U.S.] states decarbonize, the role of Quebec’s hydropower for the northeast [of the U.S.] increasingly becomes that of a virtual energy storage resource rather than a generation resource,” wrote the MIT group. “Two-way trading of electricity with Quebec helps northeastern [U.S.] states balance renewable intermittency at multiple timescales, mitigating the daily mismatch between solar and evening peak demand, the synoptic (multi-daily) mismatch between demand and wind output, and the seasonal mismatch between high summer demand and low summer wind output,” the paper noted.
If transmission capacity were extended across the two regions, the rate at which Quebec could be “charged and discharged”, would increase, the researchers added.