This project focuses on optimum design and assessment of energy systems at urban and neighbourhood scale. The novel concept of a multi energy hub is used in this context. The potential of energy hubs to integrate a higher fraction of renewable energy sources into the energy grid, the role of energy storage and emerging energy technologies in energy hubs are some of the aspects that are evaluated in this project. From a building perspective, the influence of retrofitting on building energy efficiency and subsequently on energy system sizing will be evaluated. It is important to consider a number of aspects when designing and operating energy systems. This project focuses on bridging all these aspects through multi-criterion assessment and decision making techniques where future investors and energy system operators can benefit.