District Cooling (DC) is based on centralized production of cold water, which is distributed to customers in a closed loop underground pipe network. DC systems can exploit renewable energy sources and excess energy, significantly contributing to decarbonization of the heating and cooling sector. Furthermore, as they usually make use of thermal energy storage in order to meet peak cooling demand during warm summer days, they will in the future offer increasingly valuable flexibility to the electricity grid, which makes them economically attractive from the perspective of national and regional energy planning. Attention in this report is put on cooling sources and on cooling production technologies, with the intent of guiding readers through the many available options for implementing or expanding sustainable DC systems that can meet sustainability requirements set at national, European and international levels. The current guideline report first explains what DC is, and why it can be beneficial for society and investors (Chapter 2). Chapter 3 provides an overview of DC development, followed by a detailed description of energy sources and cold generation technologies Chapter 4 and by a comprehensive list of best practices as case studies Chapter 5. Chapter 6 extensively considers design aspects of a DC system, from feasibility evaluation to maintenance. Chapter 7 is about basic and advanced control logics and concludes the technical section. Chapter 8 provides a methodology for estimating the cooling demand of a district, which is the first action to assess whether DC can be economically feasible. Chapter 9 shows a list of innovative District Energy concepts, whereas Chapter 10 is an overview of potential business models for DC systems. Finally, Chapter 11 explains the role of public authorities in the development of DC projects.

This report has been independently funded by the International Energy Agency Technology Collaboration Programme on District Heating and Cooling including Combined Heat and Power (IEA DHC).