Deep decarbonization requires shifting electricity generation to solar power, wind power and other zero-carbon resources. It will also entail electrifying many millions of energy end uses that now rely on fuel combustion, including motor vehicles as well as buildings heated by natural gas or fuel oil.
This transition creates new challenges for the electric grid, which must meet new power needs with distinctive demand profiles while reliably tapping intermittent sources of supply. Some of the additional clean power capacity will take the form of distributed energy resources (DERs). Grid-connected electric vehicle (EV) batteries will be a distributed load as well as a potential form of transient energy storage. Wireless charging promises greatly improved convenience and flexibility for EVs, but its varying power demands will present further challenges for robust connection to the grid. Also highly distributed will be building-based energy storage systems and end-use residential, commercial and industrial loads connected to enable flexible control.
U-M Energy Institute faculty affiliates are developing innovative solutions for integrating these ever more diverse supply and demand technologies into the electric grid of the future. Research to support EV integration, for example, includes the developing dynamically reconfigurable power electronics and optimal planning algorithms. Also needed are real-time control methods that enable second-to-minute timescale coordination of batteries in both EVs and buildings to maximize the utilization of renewable resources. Advanced systems analysis methods evaluate the emissions reduction potential of new technologies while examining how evolving energy systems respond to market conditions and to the heightened stress on the system due to the changing climate.
U-M’s progress in this arena is seen in recent results such as:
- Applying sophisticated circuit design techniques to overcome the challenges of voltage imbalance in grids having a high penetration of distributed solar photovoltaic (PV) systems, an advance made by doctoral student Mengqi Yao and UMEI faculty affiliate Johanna Mathieu.
- A new calibration strategy for fair and accurate measurement of the wireless power transfer to electric vehicles, including a new power transfer standard as well as a robust calibration path, published by doctoral student Sung Yul Chu and UMEI faculty affiliate Al-Thaddeus Avestruz.
- An improved algorithm for estimating key parameters related to states of charge and states of health for lithium-ion batteries, using a sequential approach based on varying frequency current injection, developed by faculty affiliates Heath Hoffman and Jing Sun with their students and collaborators.
- An assessment of how a hotter climate can impact electricity systems through the compounding effects of higher power demand and lower generating ability during high-stress times on a power grid, based on modeling by faculty affiliate Michael Craig and his colleagues.
These insights and innovations are just a few of the advances being made by the diverse group of UMEI faculty affiliates from several schools and colleges who are researching ways to integrate new technologies and control systems into the clean, multisector-serving power grids of the future.