Boaz microgrid project uses batteries to improve electric power resiliency

BOAZ - The days of watching the sky and wondering if the next storm will bring yet another blackout, are coming to an end in this tiny village in southwestern Wisconsin.

For years, the Richland County community of 129 has dealt with more than it's share of power outages. The culprit has always been known: an aging 15-mile long power line that is the village's sole source of electricity.

Most electric customers are on a loop that provides some protective redundancy. Not so in Boaz – when that line goes down, the lights go out.

Tucked into a valley surrounded by rolling hills about an hour's drive northwest of the confluence of the Wisconsin and Mississippi rivers, the village's size and remote location has meant residents often waited longer than others for power to be restored.

Last week, residents and Alliant Energy employees gathered a little more than a mile outside of Boaz to celebrate completion of a new $3.5 million microgrid – a bank of batteries that can store enough energy to power the entire town and release it via an underground cable within seconds of a power interruption.

The 400-kilowatt battery system is built to power all of Boaz for eight hours of peak demand, like a 90 degree day after a summer storm. If residents help by managing their use it could power the village through a much longer outage.

That's a big deal in a community where a loss of power shuts down the village's sewer system, residents' private wells stop working, furnaces won't light, and elderly residents lose use of their CPAP machines and other medical devices, said Jean Nicks, the village president.

When a winter outage lasted almost a full day, the village took its most vulnerable residents to Dayton Township, another small community about a 15 minute drive west because there were no in-town options for keeping them warm, she said.

"It's reassuring that we're never going to be out of power," Nicks said. "You know, in this day and age, how many blackouts you see in big cities. Well, I know we're not a big city, but its the same thought process. We don't want to be out of power."

Microgrids have been built in Wisconsin to power businesses, government buildings and community centers, but Boaz's is the first in the state that's built to fully power a community, Alliant officials said.

Before building it, the utility considered 20 other locations, taking into consideration how those communities are connected to the electric grid, the frequency of power outages, their duration and how many customers were affected.

Boaz came out as the best choice. The community had lost power 10 times, and at least twice for more than 7 hours, during the three years reviewed by the utility, said Alliant Lead Engineer Mike Graves.

"Because Boaz is 15 miles from the (substation), it really is in an ideal location for this kind of microgrid because we couldn't get to it any other way – you can't run another wire in from a different direction and it had some big outages, too," Graves said.

Alliant could have addressed Boaz's reliability problem by burying the power line, but cost estimates determined the microgrid could be built at, or below, the cost of burying the line, Graves said.

Equally important is that it provided the right conditions and scale for testing the technology and evaluating for use in additional locations, said Mike Bremel, Alliant's director of engineering and customer solutions.

"It's one very unique site because the town is small enough where we could do a pilot that's large enough in size to get valuable data, but not too large to break the bank," he said.

The Boaz microgrid is one of a half dozen places in Wisconsin and Iowa that Alliant is testing different uses of battery technology. Each is happening at a time when the cost of batteries is coming down and tax credits via the federal Inflation Reduction Act further reduce the cost, Bremel said.

In Iowa, the company is testing batteries as a way to locally manage electric loads in areas with high concentrations of rooftop solar installations by storing energy in batteries during the day, when a lot of energy is produced and then releasing it at night.

Like the Boaz microgrid, Bremel said, the Iowa projects also promise to be a more cost-effective way of managing power.

"When you've got two-way energy flows on your distribution grid, which is newer with people having their own generation, you can either significantly overbuild your capacity of your poles and wires and transformers, or you can work to (even out) peaks and valleys with batteries," Bremel said.

Utilities across the country are making significant investments in their electricity distribution networks to better protect customers from increasing frequent and longer service disruptions.

Those blackouts are the result of a trifecta of issues: Climate change is resulting in bigger and more frequent storms, an aging distribution system that largely dates to the 1970s or before, and unprecedented demand during heat waves that max out local power grids.

According to the U.S. Energy Information Administration, the average duration of a power outage in the U.S. increased from about 3.5 hours in 2013 to more than 7 hours in 2021, the most recent year for which the agency has released data. In that period the frequency of outages increased from 1.2 to 1.42 events per customer per year.

Alliant hopes that microgrids and other battery-backup systems can become a larger part of the mix of solutions that improves the reliability of its distribution network.

"That's why we went down this path with microgrid," Bremel said. "It provided us the same level of reliability and resiliency that we were looking for, but at the same time, it was providing us the opportunity to learn how microgrids can be integrated into the distribution system."

Nicks said she and her husband, Kevin, have noticed brief flickers when Alliant technicians tested the microgrid's switching system. Now, she's anxious for a longer duration test and an opportunity to see how the system might perform during an extended outage.

"I know, this is this is the first one and you're gonna see more and more of them, especially when you see so many communities with power outages," she said. "Hopefully, knock on wood, that will be a thing of the past."