Battery Storage and Safety Protocols: the Case of APS

Arizona Public Service (APS), a utility company combining solar with storage in the US, has detailed its extensive report on a fire and explosion involving its lithium-ion batteries, reports GreenTech Media. The electric utility recommends several safety measures which are all considered important to Mexico’s up-and-coming storage sector.

APS presented the report to its legislators after working together with DNV GL in the creation process, which includes important new safety measures that could prevent dangerous situations for other battery storage facilities. The fire at the APS’ McMicken facility in April 2019 was caused by a battery container catching fire. First-responders tried to open the door, which caused an explosion causing injuries to several workers. Fortunately, the fire itself did not spread out. Nonetheless, a built-in aerosol fire suppressant was unable to stop the release of explosive gasses. After the opening of the door brought oxygen into the mix, the explosion occurred.

Rather than hiding from potential backlash, APS looked for the opportunity to learn from what went wrong and enhance safety measures, said Scott Bordenkircher, Director of Technology Integration and Innovation at APS. “Conversations and learnings around an event like this are hypercritical, because that is how you get the information out that needs to be considered by the next generation,” he noted.

The report’s findings suggest to build better ventilation for explosive gases and to equip containers with much more powerful fire suppression measures. Further remote sensors can enhance safety and cooling systems could help rule out the spread of the fire if it does occur. Finally, first responders can benefit from being trained on issues regarding batteries.

It is clear that the global energy sector still has a lot to learn about batteries and how they function. Even though the failure presented in the battery that caused the fire is one of common knowledge, APS did not expect it to occur so soon. “Over a long period of time it may be kind of expected but nowhere near the severity we saw in this short period of time at this system,” Bordenkircher said.

In Mexico, battery storage is relatively new. Nonetheless, its popularity is expected to grow because major companies are taking advantage of the opportunities battery storage provide. It is an attractive option for Mexican states as well, said Rodrigo Osorio, head of the Energy Agency of Puebla in an interview with MBN. “We plan to have a healthy balance in Puebla’s energy mix. We would like to have a solar park with flow batteries to mitigate energy peaks.” In May 2019, the first solar-plus-storage project materialized in the country, reported PV Magazine. Aura Solar III, located in the Baja California, was constructed by Elmya for the Mexican company Gauss Energía. Even though the government is yet to issue regulations on the issue, the market potential for battery storage is rapidly growing.