From sectorial studies towards decision support through integral assessment of energy systems

The public, opinion leaders and decision-makers ask for clear answers on issues concerning the energy sector and electricity generation in particular. Is it feasible to phase out nuclear power in countries extensively relying on nuclear electricity supply and simultaneously reduce greenhouse gas emissions? What are the environmental and economic implications of enhanced uses of cogeneration systems, renewable sources and heat pumps? How do the various energy carriers compare with respect to accident risks? How would internalisation of external costs affect the relative competitiveness of the various means of electricity production? What can we expect from the prospective technological advancements during the next two or three decades? Which systems or energy mixes come closest to the ideal of being cheap, environmentally clean, reliable and at the same time exhibit low accident risks? The Swiss GaBE Project on 'Comprehensive Assessment of Energy Systems' provides answers to many issues in the Swiss and international energy arena. A systematic, multi-disciplinary, bottom-up methodology for the assessment of energy systems, has been established and implemented. It covers environmental analysis, risk assessment and economic studies, which are supported by the extensive databases developed in this work. Apart from technical and economic aspects an integrated approach needs to consider also social preferences. The applications of multi-criteria analysis within GaBE demonstrate the use of a framework that allows decision-makers to simultaneously address the often conflicting socio-economic and ecological criteria. Case studies are being conducted in order to evaluate the performance of energy systems with respect to sustainability. Based on these experiences EnergyGame, a tool primarily intended for communication but having a substantial analytical power, has been developed. It offers any interested user to evaluate the various electricity supply options by combining the established knowledge base (represented by the major aggregated GaBE results), with own preferences. In this way the acquired, scientifically based insights on controversial matters such as severe accidents risks may be fully utilised but space is left for accounting for personal values