Electric utility Arizona Public Service Co. said yesterday it would delay some of its battery storage facility projects after a fire and explosion at a storage site four months ago prompted an investigation.
Donald Brandt, APS chairman and CEO, discussed the post-fire delays on an earnings call for Pinnacle West Capital Corp., the utility’s parent company.
An April 19 incident at APS’s McMicken site in Surprise, Ariz., sent multiple first responders to the hospital and brought to light safety risks for utilities as they adopt battery storage technology (Greenwire, April 22).
“Because safety is our top priority, we will temporarily be delaying our investments in new battery storage resources to incorporate our learnings from this incident,” Brandt said.
Those projects include 60 megawatts of storage on existing solar facilities and a new 100-MW solar facility paired with 100 MW of battery storage. The delay “reflects a thoughtful and responsible pause,” Brandt said, as the company moves forward.
Those are the only active requests for proposals (RFP) put on hold, according to an APS spokeswoman.
The company said it will use the results of its active investigation to inform any changes made to design parameters that may be implemented on future batteries.
“We will notify participants when we make adjustments to the RFP schedule,” the utility said in a statement as it reaffirmed its commitment to add 850 MW of battery energy storage to its portfolio by 2025.
Yesterday’s Pinnacle West call came less than one week after Sandra Kennedy, a commissioner with the Arizona Corporation Commission, raised concerns about the use of lithium-ion battery chemistry to fellow commissioners, staff and others in a strongly worded, multipage letter about the April incident.
Kennedy also referenced a 2012 battery fire at the APS Elden substation facility in Flagstaff, Ariz., as cause for concern.
She criticized the use of lithium-ion batteries — particularly those that release hydrogen fluoride in the event of a fire and/or explosion — stored at some APS facilities. She called those types of batteries “not prudent” and said they create “unacceptable risks.”
“Other utility scale battery technologies or those with chemistries that do not have an associated risk of a release of hydrogen fluoride should be utilized,” Kennedy wrote. “There are also energy storage technologies that do not utilize batteries at all.”
Kennedy identified other types of utility-scale battery technologies — including liquid flow and liquid metal batteries — which could be used.
Todd Olinsky-Paul, a project director at the Clean Energy Group, noted that lithium-ion remains the market leader and that other batteries, such as some of those referenced by Kennedy, are largely still in development in laboratories. The reality, Olinsky-Paul said, is that lithium-ion technology has advanced faster than regulatory structures.
“The issue is not that it’s a bad technology,” Olinsky-Paul said. “The issue is that policy and regulatory structures have to catch up with the technology, and that’s a process that’s happening right now.”
The electric vehicle industry is a chief sector driving the lithium-ion market, he said. And while fires and explosions like at the McMicken site are certainly tragedies, they are also a part of the learning process that will inform future rules and regulation, Olinsky-Paul said.
Although a review of the April 19 equipment failure is ongoing, the investigation has moved into its second phase, according to an Aug. 7 update from APS. All but one of 378 battery modules from the installation were safely discharged on site, the utility said, and the final one is set to be discharged next week.
Among other things, the second phase includes a re-creation of events and a modeling of factors that may have contributed to the equipment failure.
“I want to reinforce that we remain committed to investing in new clean energy resources, including battery storage,” Brandt said on yesterday’s call.
Source: E&E News