Proceedings of International Workshop on Policy Integration Towards Sustainable Urban Energy Use for Cities in Asia, 4-5 February 2003 (East West Center, Honolulu, Hawaii) © 2003 Institute for Global Environmental Strategies All rights reserved. Energy, Emissions and Urban Sustainability: The Reference Sustainability System Module for London P J G Pearson *a , D Rose b , M A Leach c With: D Butler a , J Dawes b , T J Foxon c and D Hutchinson d 1. Introduction: The reference sustainability system This paper reports on part of an inter-disciplinary research project aimed at investigating a systems approach to the sustainability of cities. e The research aimed to develop a methodology, the Reference Sustainability System (RSS), for representing the energy, resource and material flows on which the environmental sustainability of cities depends, and thereby to contribute to a more systematic assessment of the potential of technological and resource management strategies to encourage sustainability. The project created an RSS model consisting of four separate but interrelated network modules covering the material or resource flows needed to satisfy urban household demand for paper, piped water, bottled water and energy. The modelling of this sub-set of urban flows enables the study of different aspects of the life-cycle and also allows for waste management, recycling and re-use and the emission of multiple ‘residuals’ to air, water and solid wastes. The study was based on data for London. This paper reports on the energy module. f The Reference Sustainability System (RSS) is an adaptation and extension of the Reference Energy System (RES) methodology, first applied by the Brookhaven Laboratory in the United States in the 1970s (Meier, 1984, 1986) . Reference Energy Systems represent activities, relationships and technologies involved in the supply of energy, by using network models to describe the flow of energy through the stages of the life-cycle: from resource extraction, through conversion to delivery to satisfy end-use demands. The RSS extended the RES methodology to model the flow of other types of commodity and service, to allow for waste management, recycling and the emissions of pollutants, and to incorporate economic cosats and values. The RSS is flexible, in that it accommodates conventional and novel technologies (e.g. in energy, fossil fuels, biomass, photovoltaics, etc.) at varying scales and efficiencies. For each RSS module, the methodology was demonstrated by creating scenarios for the introduction of new technologies and resource management practices at different life-cycle stages, comparing between baseline and alternative scenarios, at a point in time and/or over time, while exploring sensitivities to different rates of penetration of new technologies/practices and to different estimated environmental externality values. The project used two approaches to exploring environmental sustainability. The first, a constrained optimisation cost-minimisation approach, * Corresponding author. Tel: +44-207-594-9298, Fax: +44-207-594-9304, E-mail: p.j.pearson@imperial.ac.uk a Director, Environmental Policy & Management Group, Dept. of Environmental Science & Technology, Imperial College London, London SW7 2AZ. b c/o Dept. of Environmental Science & Technology, Imperial College London, London SW7 2AZ. c Senior Lecturer, Dept. of Environmental Science & Technology, Imperial College London, London SW7 2AZ a Professor, Dept. of Civil & Environmental Engineering, Imperial College London, London SW7 2AZ b Strategy Directorate, Greater London Authority, Romney House Room A415, 43 Marsham Street, London SW1P 3PY. c Research Fellow, Dept. of Environmental Science & Technology, Imperial College London, London SW7 2AZ d Strategy Directorate, Greater London Authority, Romney House Room A415, 43 Marsham St reet, London SW1P 3PY. e Research funded by grant GR/K59637 from the UK Engineering & Physical Sciences Research Council’s ‘Towards Sustainable Cities’ programme. f See also Foxon et al. (1999, 2000), Leach et al. (1997).