Pathways for the European electricity supply system to 2050 – Implications of stringent CO2 reductions

Doktorsavhandling, 2009

This thesis, which consists of four separate papers, investigates possible pathways for the European electricity supply systems to meet stringent CO2 emission reductions. Assessments are made for single EU member states, selected regions and the EU as a whole. The analyses are based on modelling scenarios with the aid of a technoeconomic model developed during the thesis work. This model has the objective of finding cost-efficient investment strategies within the electricity supply system until mid-century (2050). Special emphasis is put on the transition from the present system to a system which meets stringent CO2 reduction targets, considering timing of new investments and technology choices. Thus, the existing capital stock (power plants) is included in the model through application of a detailed database, the Chalmers energy infrastructure database, providing information (e.g. fuel type, capacity and age structure) on present and planned power plants down to block level for European power plants. Assuming technical lifetimes for power plants in the database gives residual capacities remaining over the period studied, which together with new investments meet projected electricity demand. New investment options are limited to presently known technologies and aggregated into technology classes (e.g. hard coal condensing power and onshore wind power). European analyses include assessments of fully integrated markets for electricity, CO2 emission allowances and a joint European effort to meet the targets for renewables. The results indicate that technology options at hand and efficiency measures can help to reduce CO2 emissions from European electricity supply substantially. The studies presented here assume emission reductions within the electricity sector of up to 85% by 2050, compared to 1990 emission levels. To meet these goals, however, significant changes are required in the current infrastructures of the electricity-supply system. The challenge is not due to a lack in technologies – these are available at costs which should not be prohibitive for society and which, indeed, are expected from the EU Emission Trading Scheme (ETS) – but due to the large investment ramp-up required and to fuel-market implications as well as the institutional and logistic challenges (permitting procedures, establishing CO2 transportation systems, finding sites for wind power etc). Key measures included in this research are Carbon Capture and Storage (CCS) and large-scale employment of renewables in electricity generation. In addition, it can be seen that efficiency measures to reduce electricity demand are of great importance to reduce the strain in capacity ramp-up of CCS and renewables. Common targets on CO2 emission reductions point to differentiated strategy between member states. Thus, regions which currently have high carbon intensity and are located near suitable storage sites will benefit most from CCS implementation, whereas other regions have large potential for renewable electricity generation (e.g. coastal areas with high expectations in annual average load hours for wind power). Finally, this study has presupposed that emission targets must be met. The focus has been on how to meet the targets and what implications we may expect from different technological choices that are at hand in order to meet these targets. However, it is also clear in this analysis that the investigated technological transitions will not come about automatically. Additional policy measures will be necessary. The EU-ETS, as we know it today, is merely a beginning.