Since the opening of European electricity markets, utilities are launching green electricity products. In Switzerland the privately initiated ecolabel “naturemade star” ensures the environmental and ecolo­gi­cal quality of electricity from renewable energy sources including life cycle thinking. The evaluation method includes a simplified and partly site-specific life cycle assessment using the Eco-indicator 99 (H, A) impact assessment method. In a first step, detailed LCAs case studies were made by ESU-services for power plants and technologies which are candidates for the “naturemade star” label. Technology-specific parameters are identified that dominate the outcome of the LCA and for which data are available for the owner or operator of the power plant at issue. For photovoltaics for instance, key parameters are the annual production, the type of solar cell (single- or multi­cristalline), and the kind of installation (building integrated or mounted). Based on the knowledge gained with the detailed LCA, parameter models for photovoltaics, wind and hydroelectric power, electri­city from biogas of various sources and from wood have been established on a spread­sheet-basis. They are easy to handle for SME operators or manufacturers of the candidate power plants. With the help of the key parameter models, operators of small and medium size power plants can carry out the required LCA within a few hours. At the same time they can check, whether the plant fulfils the “naturemade star” threshold or not. The threshold has been set to 50% of the environmental impact in Eco-indicator 99 (hierarchist) points of a gas combined cycle power plant.

The labelling scheme for electricity was introduced in 2001 by the Association for Environmentally Friendly Electricity (VUE). A new project aims now to revise the key parameter models of several energy systems and to allow a labeling not only of electricity, but also of heat, cooling and biomethane.

Contact: Niels Jungbluth