Battery Tour Shows Minnesota Stakeholders a Cleaner, Quieter Future for the Electric System

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In November, GPI organized a tour for Minnesota utilities and members of the Minnesota Energy Storage Alliance of Indianapolis Power & Light’s (IPL’s) Harding Street Station Battery Energy Storage System, or HSS BESS. The HSS BESS is a state-of-the-art, 20MW energy storage facility connected to IPL’s transmission system.

We spent the morning listening to IPL’s Senior Strategist, Lin Franks, for Regional Transmission Organizations, Federal Energy Regulatory Commission, and Compliance Initiatives talk about the process to get the system up and running, IPL’s ongoing work with MISO (the regional grid operator) to shape its market rules and processes, and seeing performance charts that showed the battery providing grid reliability services and managing its state of charge to be continuously available. Then, we took a walk through the quietest, cleanest large-scale electric facility I’ve ever stepped foot in.

As Lin Franks explained, IPL invested in this project because of the flexibility and versatility it offers as the industry moves forward to a period of substantial transition. The facility is modular; its 244 storage nodes, each comprised of 20 battery trays with 20 batteries each (that’s 97,600 lithium ion cells for those of you counting at home) are able to be configured using both hardware and software modifications to enable to facility to provide a number of services. These “Legos,” as Ms. Franks affectionately calls them are currently configured to provide Primary Frequency Response service, but can just as easily provide frequency regulation, energy, and capacity. According to Ms. Franks, the facility can be configured to provide any service that is defined in the Tariffs of each and every Independent System Operator in the U.S.

The value of tours like this is seeing and touching an emerging technology; the first step in becoming comfortable with using it. Grid operators use a combination of standards, planning processes, experience, and intuition to keep the system in balance and lights on. Trusting the system to respond as one expects is a part maintaining this delicate balance. Our hope is that by creating these connections among stakeholders and facilitating this tactile experience, utilities and developers in Minnesota will progress toward investing in energy storage resources to enable higher penetrations of renewable energy resources and improve the reliability of the system.

Text Box: IPL’s Lin Franks demonstrates the HSS BESS’s state of charge management and primary frequency response performance.This shared experience also directly helps GPI and other MISO stakeholders develop reasonable market reforms for energy storage. For example, at the HSS BESS, we saw data that showed the response time of the battery, ramping up and down and moving between charging and discharging in seconds. We also learned about how IPL can distinguish between charging for state of charge management and charging for the provision of grid services. Ramp rate and state of charge management are critical parameters for the Automatic Generator Control Enhancement market reform recently initiated by MISO at the request of MISO and other stakeholders. This type of learning helps inform how MISO market rules should be crafted to accommodate the unique aspects of this type of resource. Furthermore, as more energy storage resources come online, understanding their behavior and needs will help refine these market reforms to ensure robust market participation is possible in MISO.