UNS: Environmental Impacts of Using Distributed Energy Storage for Power System Reserves

1510788

Johnson, Jeremiah

The objective of this project is to investigate the environmental impacts of using distributed energy storage (DES) for power system reserves and to develop operational strategies to mitigate the environmental burdens of the system. As more renewable energy sources are integrated into the power system, additional reserves are required to ensure the functionality and reliability of the system. DES is a promising alternative to generators for providing such reserves because, in general, these resources are more responsive than conventional power plants and costs are increasingly competitive. Due to their low emissions during operation, DES systems are often assumed to reduce environmental impacts. However, due to the complex nature of the power system, the use of DES may lead to negative outcomes under certain system configurations, generation mixes, and reserve requirements. Thus, it is important to thoroughly evaluate the environmental impacts of introducing DES for reserves. Using life cycle assessment (LCA), the researchers will investigate the full environmental impact of providing reserves with DES. Additionally, they will develop a reduced-form LCA that can provide real-time feedback on environmental impacts to power system operators.

This work will advance the fields of industrial ecology and power systems. To evaluate the environmental impact of using DES for power system reserves, LCA will be coupled to optimal power flow (OPF) methods. While fossil fuel combustion is expected to be a major contributor to life cycle environmental impacts, the short product lifetime and operational impacts of using DES demonstrate the importance of upstream and downstream impacts and the need for LCA to robustly determine environmental performance. A key contribution of this work is the application of model reduction techniques to develop reduced-form LCAs so that approximate impacts can be calculated in real-time and used within the OPF. These methods which support the use of LCA for active feedback response could be readily tailored for use in other systems such as transportation and water treatment. This project also advances the formulation of the OPF problem by incorporating life cycle environmental impacts into the objective function and/or constraints. This will help us understand the tradeoff between system operation costs and environmental benefits, informing system operators and policy makers. This project will advance the utility of LCA by tailoring the method to provide active feedback to systems operations. The results of this study will identify operational strategies that improve environmental outcomes for power generation and inform public policies that strategically remove of barriers to participation for DES. This project will also yield educational impacts through the involvement of undergraduate students in research activities and the development of age-appropriate educational activities for K-12 students. The team will develop a factsheet on DES distributed by the Center for Sustainable Systems at the University of Michigan, to serve as a freely available public resource for students, researchers, and policy makers. This project will also support the development of two modules to be integrated into courses for environmental professional students and electrical engineers.