Assessment of the environmental impacts of electric energy storage technologies through a life cycle assessment: development of a prospective modeling framework.
Laurent Vandepear (PhD student, civil and building engineering, USherbrooke)
Supervisor: Ben Amor
Co-supervisor: Christian Bauer
The overall capacity of stationary electricity storage units is growing due to a decrease in the cost of different technologies and the implementation of favourable regulatory frameworks. However, a significant deployment of these technologies will have direct and indirect environmental consequences that need to be accurately assessed to guide technology choices and long-term energy policies. Current environmental assessment tools have limitations and do not capture the complex effects of significant changes in the energy sector. The development of more advanced assessment methods is therefore necessary.
The goal of this research project is twofold:
Develop a forward-looking assessment framework to assess the long-term environmental impacts of changes in energy systems. This new approach will rely on the connection of the life cycle assessment method to economic modelling tools for energy systems.
Apply this new approach to the case of energy storage in order to quantify the environmental performance of different technologies within several scenarios of long-term evolution of energy systems.
A-LCA deals with the environmental impacts of batteries on the Québec electricity grid. The results show that the battery production phase cause most of the environmental impacts for the two technologies studied. The effects on global warming come mainly from the production of components in Asian countries where fossil fuels dominate the electricity mix. In addition, mining activities related to materials such as copper, gold, steel and aluminum used in battery components are responsible for significant environmental impacts.
The C-LCA analyzes the long-term effects (post-2035) of the same types of energy storage units but in the case of integration into the Swiss energy system. This analysis in addition to the direct effects studied in A-LCA also includes the substitution effects caused by batteries on electrical systems. The results obtained thus show environmental benefits in twelve of the fifteen categories evaluated. These can be explained by the fact that batteries allow the use of surpluses from intermittent renewable sources of electricity that replace electricity from non-renewable sources.
The next phase of the project is the development of the methods for the integration of Energy Systems Modeling Tools (TIMES) and LCA models. Both types of models are indeed harmonized and LCA-based environmental indicators are added to the TIMES tool. This work offers a very comprehensive prospective and dynamic environmental assessment of the Swiss energy system and the energy storage tools that are used. Some complementary themes are discussed, such as the optimization of the TIMES model based on environmental performance, the indirect effects caused by energy storage systems and the uncertainties related to these results.
In terms of methods, this work improves the way energy processes are modelled in LCA. This new approach has a prospective orientation, integrates the temporal dynamics of the energy sector and relies on data of a superior completeness thanks to the hybridization of the LCA and energy models. The created tool is transparent and reusable, and the various data sources and model components can be easily modified by future users.
Storage technologies will lead to significant changes in the mix of energy mixes as well as a variety of additional implications that are not covered by current LCA tools. The environmental performance of this type of unit is studied by integrating these elements using the new evaluation framework. Any entity concerned with the problem of energy storage or wishing to establish an energy strategy will be able to make more informed choices thanks to the results and tools of this project.