Invinity Energy Systems (AIM:IES) said customer Indian Energy's vanadium flow battery system at the Viejas Casino & Resort near San Diego has now delivered more than 1 GWh of energy, a milestone the AIM-listed battery maker is using to underline the technology's reliability in commercial operation.
The system was commissioned in late 2025 and has run near-continuously since, charging from on-site solar generation and discharging to support resort operations at what Invinity describes as California's largest tribal microgrid installation, featuring a 15 MW solar array and backed by the California Energy Commission.
The milestone follows Invinity's disclosure in August that its global operating fleet of VS3 and Endurium systems had surpassed 10 GWh of cumulative energy dispatched, up 85% year on year, with the Viejas installation singled out then as a strong performer exceeding warranted metrics with more than 0.5 GWh delivered.
"Invinity's battery system has proven to be a true workhorse for us, consistently performing to specification and supporting our operational requirements since commissioning," said Allen G. Cadreau, chief executive of Indian Energy.
Matt Harper, president at Invinity, said the milestone demonstrates "the maturity of our technology, the strength of our customer relationships and the growing operating track record which underpins our business."
The California Energy Commission has backed Invinity's vanadium flow battery technology through a series of grant-funded projects since 2021, according to the commission's chair, David Hochschild, who called the Viejas milestone another step in the state's transition to clean energy.
The update adds to a run of operational progress for Invinity, which is separately working toward connecting its 20.7 MWh Copwood Energy Hub in the UK, expected to become Europe's largest operating vanadium flow battery once commissioned.