Alliant battery system close to coming online

WEVER – The battery storage facility under construction between the Koch fertilizer facility in Wever and the Alliant solar field in Green Bay bottoms is close to completion.
Several officials with Alliant and FlexGen, the operations control company for the Battery Energy Storage System (BESS), were in town Wednesday to talk about the new 162 unit system in Lee County.
Devin Keber, FlexGen’s VP of Safety in Compliance, said the systems are monitored out of North Carolina 24/7 and are controlled remotely from that location.
FlexGen manages, optimizes, and controls utility-scale battery systems, enabling them to integrate renewables, provide grid services, and generate revenue for utilities, data centers, and other large users.
Abichu Abebe, Engineering Manager for Alliant Energy, said there were 128 units and 34 inverters  that make up the Battery Energy Storage System (BESS). He said the site is designed for 99 megawatts of power and is paired with the 150 megawatt solar field in the county.
The power generated goes directly into the electrical grid and that should start happening in June this year. Construction started in May, Abebe said.
The units sit on concrete pads on a large fenced and gated site just north of 180th Street about a quarter mile in from Hwy. 61.
Keber said the battery technology is lithium iron phosphate which he said makes them less susceptible to thermal runaway. Thermal runaway is a dangerous, self-sustaining chain reaction where a battery cell overheats uncontrollably, generating heat faster than it can dissipate, leading to a rapid temperature increase, release of flammable gases, smoke, fire, and potentially explosion or violent venting, according to Underwriters Laboratories, an independent global safety organization.
Lithium iron phosphate is a safer alternative for lithium ion batteries due to its lack of cobalt and is common in solar power storage systems.
“You can beat it up, honestly,” he said. “It just keeps on going and so that helps with the degradation curve. In other words, it allows the battery to keep working longer so they won’t have to replace it as often. Right now, these are sitting at 13 to 15 years before we even have to think about recycling them.”
Abebe said the facility was originally built to last 20 years. The original application filed with the Iowa Utlitiies Board, now the Iowa Utilities Commission was approved at 75 MW.
Keber said the system currently meets NFPA (National Fire Protection Association) standards for safety and a multitude of UL standards as well.

In the event of overheating on site that actually would cause a fire, Keber said first responders including firefighters in the immediate area would handle the incident from a defensive posture.
He said he was in the area to work with first responders and educate them on the specific hazards they may encounter in an incident; what the standards of the industry and best practices are if they actually respond to an incident at these fires;  and ultimately let the firemen get on site to see what’s actually going on.
“The industry standard is a defensive stance. That’s what you see on the news. They sit back and spray water on top of it. And to take that one step further, the only time they would use water is if they think it may spread to another cabinet,” Keber said.
“It’s not a huge manpower implication. Honestly, you can get away with a couple fire trucks going to manage it.”
He said worst case scenario is that an entire unit catches on fire. He said technology allows the units to actually work through monitoring to help vent heat to the air so you don’t get to the level of explosion.
“Any time there is any fire alarm, it opens up all the contacts to reduce any escalation,” he said.
Adam Sodersten, senior communications specialist with Alliant, said the upside of the facility is that it provides a more reliable source of energy for Alliant customers. He stopped short of saying bills will be reduced with the new system online, but said having a more readily available supply of energy will help keep prices in line.
“We’re not having to build more energy production. We’re able to hold it, utilize it, and store until you need it,” he said. “It’s a way to make sure costs are held where we have them.
“The idea of these batteries is they can hold the energy produced by the solar field when maybe it’s not needed at that moment. The batteries hold it and then when it’s needed, it’s used.”
He said their goal was to provide energy and make sure it’s reliable.
According to Alliant's website, battery storage systems charge from the grid when energy demand is low or directly from wind projects when excess renewable energy is abundant. They discharge energy when demand increases, such as on hot summer or cold winter days. The ability to capture and store energy to use when needed improves the overall benefit of renewable resources.
The website also indicated the company is committed to responsible end-of-life plans for the system. The company’s goal is to recycle or identify secondary markets for battery equipment when it reaches end-of-life. The company claims batteries contain valuable components and minerals that can be reused to make new batteries and federal and private investments are expanding commercial battery recycling efforts in the U.S.