Battery energy storage company presents plans to commission

One of Spearmint Energy's battery energy modules at a Texas location. (Spearmint Energy website)

By Charlene Sims, info@linncountyjournal.com

MOUND CITY – The Linn County Commissioners heard a presentation from Blake Johnson, representative of  Spearmint Energy, on Monday, March 31. Blake Johnson explained that Spearmint Energy was in the early stages of building a battery energy storage facility, called Silverfield in northern Linn County.  

Blake Johnson introduced the other people with him. He said Jenny Dean is with a group called 39 North and is assisting him with his projects on permitting as a subject matter expert.  Evan Balcombe is from a group called Fire and Risk Alliance (FRA) and he said his company works very closely with their group on our battery projects and coordination with fire departments when we’re putting emergency response plans together.

Johnson told the commissioners that the battery energy storage facility was not projected to be completed until 2028, but he wanted to come to Linn County to provide information and answer questions about the facility. He provided a video presentation about the facility and operation.

He said that he was also in Linn County to meet with the county’s planning and zoning director to learn about permits involved in building the facility. 

Last month Commissioner Alison Hamilton asked then zoning director Kent Harris to talk to  the planning board to look into the minor plat section of the regulations and also battery storage facilities and data centers. Harris is no longer employed by the county.

The commissioners asked several questions about the facility. Commissioner Jason Hightower asked if that type of facility fell under the 10-year abatement like the renewable energy companies from the state of Kansas.  Johnson said it did not, but that was being considered in the Legislature. 

He said that Spearmint would not intend to use those 10 years and not benefit the community so any type of payment in lieu of taxes (PILOT) or donation program they could put in place with the county is certainly open to discussion after permitting.

Hightower asked if the $20 million on the chart the first 10 years would be what the company would be paying in taxes or what you will be putting on our tax roll. 

Blake Johnson said that was what they would be paying in property taxes to the county. He said currently in the state of Kansas batteries are fully taxed for both real and personal property tax. He said considering depreciation, the estimate of $52 million in taxes would be over the 30 year life of the contract.

Johnson said that the industry was becoming safer and putting more standards and codes in place.

Commission Chair Jim Johnson asked what type of equipment it took to fight a battery fire.

Balcombe said there really wasn’t specialized equipment for fighting storage battery fires right now. He said that batteries will typically burn themselves out. That is the plan under NFPA55, which is the code that systems are built around now. The battery energy storage systems contain a failure either to the cell or to the module.

“A cell failure itself does not have any special way to put it out,” Balcombe explained. “It is usually non-intervention that is the method and the newer systems will contain that fire to a single cabinet or module and then it will extinguish itself.”

Blake Johnson added that the project will be monitored around the clock both onsite and remotely. The facility itself will be gated with secure access so it won’t be open to the public. 

He said that he was planning on meeting with Linn County Fire Chief Randy Hegwald while he was in the county and they were going to discuss the specifics of batteries themselves and kind of dive into the chemistry a bit more. He said one of the things they would put in place is a very robust emergency response plan. 

Commission Johnson asked what hazards are associated with a fire.

Balcombe answered that there are hazards associated with the fire just like anything else that is burning you can get toxic gases coming off it. The three main gases that come off a battery failure are carbon monoxide, carbon dioxide and hydrogen. Those dissipate in the atmosphere. But if you were in that container, which those are non-walking containers, those will be hazards. The same hazards as any fire. There are explosion hazards if you don’t have explosion mitigation like explosion prevention systems. All knew cabinets have explosion prevention systems.

Commissioner Johnson asked if there would be soil contamination with these batteries.

Balcombe said that there had been studies of sites that had fires and there had been no contamination there. 

Blake Johnson said that his company had started field studies for wetlands, habitat and threatened and endangered species. 

He explained the size and purpose of the Silverfield facility and the plan for where it is to be located. Johnson said it was just north of La Cygne in the very northeast portion of Linn county.

He told the commissioners that the project is directly north of the Evergy power plant. We’re not on Evergy property but we are directly abutting it. It is just kind of wedged between that and some kind of quarry.

He also provided information about the Spearmint Energy company. He told the commissioners that it was a privately owned U.S. company. The headquarters are in Miami, Florida and another office in Minneapolis, Minn., which is where he is based out of.

He told the commissioners that Spearmint had 20-plus projects in development with 10 gigawatt hours of storage in four regions of the U.S. He said one project was operating in Crane County, Texas, and then two more in construction currently and should have about three more through 2025 starting construction.

He said that Spearmint’s projects were stand alone projects not directly affiliated with any specific electrical generation source. The projects are not directly affiliated with any loads or anything like data centers. That’s not a part of this project or Spearmint’s development portfolio.

“The gist of what we are doing is storing electricity in the batteries and then dispersing it back to the grid,” he explained. “So, really what we’re doing is when there’s dips in demand but more of a peak in supply, our batteries could charge at an economical price and then when there’s a peak in demand, we can then offset some of those peaks with the storage asset.”

He said that physically the batteries very much resemble storage containers, they stand about 10 feet tall and are on a fairly small footprint as well. The batteries themselves sit on maybe three to five acres. The entire site will be around 15 to 20 acres just to incorporate access roads and onsite substations and things like that.

He continued, “So when I am talking about an enclosure, lithium ion batteries are sort of the industry standard. So when you are looking at the enclosure, when you open that up, you can’t walk inside of it but you open up from the outside, there’s all these racks that hold modules which then hold the battery cells.”

Silverfield, itself, is planned to be a 300 megawatt, 1200 megawatt hour, system. As a reference, the company has leased about 25 acres,” said Johnson. “The batteries themselves will be on about four acres of that. Again, a stand-alone facility. The nearest residence will be over a quarter mile (away).

“If constructed, it will be a great addition to the local tax revenue as well as its very good at assisting the grid, both in the case if there were blackouts or brownouts. It’s an excellent resource to interject power back onto the grid. It also helps with the longevity of existing infrastructure.” 

He told the commissioners that there was a transmission line running through the project and Spearmint intends through their interconnection to tap directly into that line so they would not be building additional lines.

Commissioner Hamilton told Johnson that there was ongoing discussion on whether the county even wanted a battery storage facility.

Hamilton said that just for public knowledge, right now, this project could have a conditional-use permit because they were not prohibited.