Stermann, R. (2011). Integrating wind power into the German electricity grid : a comparison of attributional and consequential LCA [Master Thesis, Technische Universität Wien]. reposiTUm. https://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-57075
Renewable energies are high on the political agenda for resource depletion, security of supply and climate change concerns. In Germany, wind power is continuously gaining shares in the power plant park. The question arises to what extent its integration into the electricity mix is environmentally beneficial. Life Cycle Assessment (LCA), one of the most prominent ecological assessment tools, can help giving answers. However, different ways exist to carry out LCAs. An attributional LCA, the traditional and most widely used LCA approach, investigates the environmentally relevant flows over a life cycle. A consequential LCA, promoted as a new alternative, explicitly investigates the changes resulting from a specific decision. Both attributional and consequential LCA can be used to investigate the environmental benefits from the integration of wind power into a national electricity grid. For this reason, it is of interest to carry out both LCA types on this decision in Germany, looking backwards at the year 2006. The aim is to determine to what extent a consequential LCA, as opposed to an attributional LCA, leads to changes in the evaluation of the environmental performance of intermittent power generation techniques and their integration into the grid. The case of wind power is of particular interest because of its growing importance and its intermittent nature. The modeling showed that the introduction of wind power leads to environmental benefits in various areas, notably caused by the replacement of fossil fired power generation through wind. However, attributional and consequential LCA show different results. In particular, this difference comes from the inclusion of two effects in the consequential LCA, ignored in the attributional LCA: 1) the substitutive effects from the integration of wind power into the grid and 2) the altered operation of the conventional power plant mix balancing the system to compensate for the fluctuating wind power generation. In this study, it was demonstrated that only a consequential LCA is able to take into account multiple and interdependent consequences of a given decision, like the decision to integrate wind power into a national electricity grid. It is therefore proposed to guide future large-scale decision-making on the basis of consequential LCA results, as opposed to attributional LCA results, whenever possible.