The Ontario Power Authority (OPA) wants to understand the pros and cons of district energy in Ontario, and its potential implications for OPA. To that end, OPA commissioned Compass Resource Management Ltd., with input from FVB Energy Inc., to conduct an analysis of the technical and economic characteristics of district energy, the market context for district energy in Ontario, and institutional issues that could influence the future development and operation of district energy systems in the province. The study includes a technical, economic and environmental analysis of district energy based on a representative set of neighbourhood sizes/types and district energy technologies. Three case studies were also prepared to illustrate real-world outcomes and issues. Finally, ten interviews were conducted across the district energy supply chain in Ontario to help frame district energy opportunities and issues within the province.