In 2010 Getting to Carbon Neutral: A Guide for Canadian Municipalities (pdf) was prepared for Toronto and Region Conservation by Sustainable Infrastructure Group University of Toronto.
It is important to note that this report was prepared seven or more years ago, and the zero carbon neutral target does not have an identified year. It was also published before the IPCC reported that CO2 had a carbon budget (a limit on the cumulative CO2 emissions) which we have calculated should be exceeded a year or more before 2025 for Toronto if we are to make our equitable contribution to this budget.
Climate Action Now has documented the assumptions of the most recent IPCC report (released in 2014) as well as the carbon budgets for Toronto, Ontario and Canada.