An Interactive Framework for Building and Analysing Models of Urban Energy Systems

This paper describes a software framework for building and analysing models of urban energy systems. The framework consists of a technology database and components for model assembly and networking coupled with a graphical user interface. The technology database, which is implemented as a Protege ontology, describes the available energy conversion, storage and transportation processes. The spatial framework for the model is defined by a cityspace object. Distributed energy demands are specified within this cityspace, and it also identifies potential locations for energy conversion processes and links for resource flows across infrastructure networks. The user interface instantiates and assembles framework objects into an overall object model of the system. The assembled object model can be used to define optimization scenarios for the design of urban energy systems with specific goals and constraints such as minimising investment costs while meeting emission targets. These scenarios can be submitted across a network to a solver on a remote host to obtain an optimal design of the urban energy system. The results are displayed by the user interface at two levels: an aggregate level with key performance indicators and graphical analysis for the city as a whole, and a detailed level showing information about individual cells and flows between cells. The interface also provides charts and summaries for comparing alternative scenarios with variations in emission targets, cost parameters and available technologies.