A new report by economists at The Brattle Group uses a detailed power system model to examine alternative power supply portfolios for the City of Memphis, including several 100% renewable portfolios by 2050. Through this work, the Brattle economists analyzed a variety of near- and long-term resource supply options for the City of Memphis, their relative economics, and effects on system reliability. Simulating Memphis’ system with a detailed hourly model allows the study to identify potential challenges that emerge as power systems approach and ultimately reach full decarbonization.

Leveraging Brattle’s analytical work on energy efficiency, demand response, battery storage, and electric vehicle charging, the model uses a mix of both supply and demand resources to develop portfolios that complement renewable generation resources in ways that will ensure a reliable and potentially fully decarbonized power system in the future.

Residual combustion turbines fired with either natural gas or carbon free alternatives such as biogas (and ultimately renewable gas) provide seasonal flexibility, which emerges as a critical issue in (near) 100% renewable power systems.

“Our analyses show that the feasibility and cost of a 100% renewable electricity system will depend significantly on the cost of providing longer-term storage,” noted Jurgen Weiss, a Brattle principal and co-author of the study. “It goes beyond the typical long-term power system modeling, which stops short of exploring and modeling solutions to hour-to-hour, seasonal, or multi-year challenges. The analysis presents solutions that would be useful in supporting operational challenges while moving toward higher levels of renewable generation in the future.”

As more and more cities, towns, and states set high renewable electricity goals for the future, understanding and analyzing the potential functioning and economics of the resources available to them, systems constraints, and potential solutions will become increasingly important.

The report, “Power to Memphis: Options for a Reliable, Affordable and Greener Future,” is authored by Jurgen Weiss, Judy Chang, Nicholas Powers, and Kai Van Horn. The report is also available on the Friends of the Earth website.

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