Quebec and Ontario have signed a $1-billion annual hydroelectricity deal.

Ontario Premier Kathleen Wynne and Quebec's Philippe Couillard met today for the official signing ceremony for the agreement, which was announced in October.

The deal allows Ontario to import up to two terawatt hours of electricity annually over seven years from Quebec — or enough energy to power a city of roughly 200,000 people.

Wynne says Ontario will save $70 million over the life of the deal versus previous energy cost forecasts and that the province's annual greenhouse gas emissions will be reduced by about one million tonnes a year.

Couillard said the agreement serves as a model for future deals between Quebec and other provinces.

Ontario is also scheduled to join Quebec and California's cap-and-trade carbon market in January.