Surprise was rocked by an explosion April 19 when a battery storage unit owned by Arizona Public Service erupted in a fireball that left city and utility industry officials reeling.

APS spokeswoman Jill Hanks said the utility has three energy storage facilities like the one in Surprise but none in Peoria.

However, a much larger facility is planned for neighboring Youngtown, which the Peoria Fire-Medical Department serves when needed.

This is opening the door for surrounding departments to look at new code that addresses battery facilities.

Ms. Hanks said the investigation is still ongoing and cannot release information until it is complete.

“APS and the investigative team intend to share what they can of the ultimate findings, especially to the extent they are helpful to first response agencies and the energy storage industry,” she said. “Safety is the priority for everyone involved and APS will continue to work with first responder and municipal partners to comply with any revised or new codes that come about.”

Four Peoria Fire-Medical Department firefighters were injured fighting the fire at the APS McMicken Energy Storage facility near Grand Avenue and Deer Valley Road in Surprise.

Peoria Deputy Fire Chief Stacy A. Irvine said one is back to work full-time, two are restricted to office duties per their physicians, and one is still on a no-work status per his physician.

The Peoria Fire-Medical Department is a member of the Automatic-Aid Dispatch Consortium, which allows for the closest, most-appropriate unit to respond to an incident. On the day of the accident, the Surprise HazMat team had been dispatched to a medical call just minutes before the McMicken Energy Storage facility call. Peoria’s HazMat team was the next closest crew to respond.

Sun City Fire and Medical provides fire and medical coverage for the town of Youngtown. But Ms. Irvine said the automatic aid system is why the Peoria fire department could respond to a location in Youngtown if needed, to secure the area, evacuate residents in immediate danger, and mitigate the hazard if possible.

She said scientists and manufacturers investigating the fire will be a big part of learning how to avoid a battery explosion in the future, and local jurisdictions are updating their fire codes to now include Battery Energy Storage Systems.

But she did not have immediate details about updtated codes in Peoria.

Youngtown

A much larger battery facility is planned by Invenergy officials for a Youngtown location south of Olive Avenue between 111th Avenue and the QuikTrip gas station and convenience store. The Surprise incident has Youngtown and Sun City Fire and Medical Department officials concerned enough to be taking precautions to try and prevent a repeat of a similar accident.

“The Surprise battery storage unit did not have a permit, except for the chain link fence around it,” said Sun City Fire Marshal Jim Fox. “Surprise Fire Department did not know about the facility and what it was.”

To avoid a similar incident, SCFMD officials adopted new codes, Oct. 15.

While the SCFMD board was to consider a variety of codes — fire, building, mechanical and others — for the 2018 cycle, they are also including amendments being developed specifically for battery storage for the 2021 cycle.

“Technology has advanced so quickly that battery storage was not a consideration in previous cycles,” Mr. Fox said.

The International Code Council revises codes on a three-year cycle. SCFMD adopted new codes in 2009 and 2012, and are now preparing to adopt 2018 revisions. Mr. Fox said SCFMD did not adopt the 2015 cycle because they believed it did not spell out enough detail.

SCFMD officials are working with Youngtown leaders to help make the Invenergy facility as safe as possible.

“We can make this safe,” Mr. Fox said. “We already have certain conditions as part of their use permit with the town of Youngtown.”

Invenergy officials are in full cooperation, according to Susan Innis, Invenergy senior manager for renewable development.

“We have agreed to follow all the codes that are put in place,” she told the SCFMD board during its Oct. 8 meeting.

She added the global sustainable energy company, which completed 146 worldwide projects, has time to adjust its plans for the Youngtown facility according to the codes. Invenergy officials plan to seek permits in the spring of 2020, start construction in 2021 with an expected completion in summer 2021.

“These facilities will be built, so we need to regulate them,” Mr. Fox said.

Representatives of fire departments in Sun City, Surprise, Peoria and Phoenix worked together to write the codes under consideration for adoption, according to Mr. Fox.

“One of the codes will give us the authority to check their buildings at any time to see any changes that are made,” Mr. Fox explained. “That way, we’ll all know what’s in the building and how it works.”

He also said one of the features of the planned Invenergy facility was that each battery will be individually monitored. If one begins to generate too much heat, the entire system will be shut down.

The Surprise explosion raised concerns among energy utility officials nationwide, especially regarding energy storage.

“The question of how you manage these things safely, when you’ve got thousands of these cells in close proximity, that’s still a work in progress,” Donald Sadoway, Massachusetts Institute of Technology professor and an expert in battery technology, told Utility Dive, an industry website.

In February, APS announced it will add 850 MW of battery storage and at least 100 MW of solar generation by 2025. Despite the incident at its McMicken facility, the utility plans to follow through with its plans.

“As far as we are concerned, we know that energy storage, including batteries, is vital to a clean energy future. We will continue with our plans to add clean energy projects to our system,” Lily Quezada, APS spokesperson, told Utility Dive. “[It] is a breakthrough technology that is solving important issues and challenges. We are still committed to our plans.”

The fire at its storage facility in Surprise was not the first such incident for APS. A system near Flagstaff also caught fire in 2012. APS officials said they took several key design lessons from the 2012 fire, including improving air ventilation between cabinets, incorporating a 24/7 monitoring system and the ability to send remote alarms, according to the Utility Dive article.

The new codes will require all buildings to allow emergency radio communications inside. This could require some facilities, like Banner Boswell Medical Center, 10401 W. Thunderbird Blvd., to install communication systems that allow radio connectivity throughout the building.

“There are some buildings — and Boswell is one of them — where you can connect by radio with your command or personnel outside from one side of the building but not from the other,” Mr. Fox said.

The codes are retroactive, meaning there will be no grandfathering for businesses and agencies out of compliance.

“That will be a good thing, because communication is very important for emergency responders,” said Walter Link, Sun City Fire District board member.

Philip Haldiman can be reached at 623-876-3697, phaldiman@newszap.com, or on Twitter @philiphaldiman.

News Editor Rusty Bradshaw can be reached at rbradshaw@newszap.com or follow him on Twitter @SunCitiesEditor.