What Penske Learned About Charging Electric Trucks
Penske Pilots Software to Support Electric Truck Charging
Penske is piloting an 800 kilowatt hour battery system powered by Stem's Athena smart energy storage software at Penske's heavy-duty truck charging sites in Ontario, California.

Penske is piloting an 800 kilowatt hour battery system powered by Stem's Athena smart energy storage software at Penske's heavy-duty truck charging sites in Ontario, California.
Photo: Penske
As Penske Truck Leasing continues to expand its fleet electrification efforts, the company is evaluating related technologies to support the emerging charging needs of battery electric trucks.
Earlier this year, Penske began piloting a 350 kilowatt (kW)/800 kilowatt hour (kWh) battery system powered by Stem's Athena smart energy storage software at Penske's heavy-duty truck charging sites in Ontario, California.
Stem's Athena predicts when the charging site's electricity demand will spike and uses the supplemental stored energy via on-site batteries at the optimal time to drive off-peak electricity savings and minimize utility peak demand charges, Penske officials said.
Since starting the pilot, smart energy storage has driven a 40% decrease in Penske's site peak energy consumption.
Sean Yentsch, vice president facilities at Penske, said in a press release that Penske is pleased with the initial results, and that the company will continue to continue to evaluate expanding the use of this AI-driven energy storage system as new charging positions equipped with supplemental battery storage are established.
"We collaborated with Stem and other suppliers in designing and implementing the electric vehicle charging infrastructure," Yentsch said. “We then used Stem's Athena smart energy software to optimize the electricity requirements associated with charging commercial electric trucks.”
Stem collaborated with Penske and its other suppliers in project execution, including optimizing energy tariffs, utilizing energy storage to secure funds from California Air Quality Resources as well as securing incentives from California's Self Generation Incentive Program.
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