By Julian Spector
This is not a test.
Utility Arizona Public Service has contracted for a new grid-scale battery — not to demonstrate the technology, but because it’s a lot cheaper than the conventional alternative.
The company will purchase two 1-megawatt/4-megawatt-hour storage systems from AES for the small town of Punkin Center. This 600-person hamlet, 90 miles northeast of downtown Phoenix (and known for a bar with a prominent jack-o’-lantern sign) is bumping up against the limits of its distribution grid.
The traditional approach, which APS considered, would be to upgrade the 20 miles of 21-kilovolt cables that service the town. That requires construction through hilly and mountainous terrain, with considerable expense and local disruption.
The utility decided that batteries would be cheaper.
By tucking the AES storage systems on APS-owned land in Punkin Center, the company can deliver locally stored power on the 20 to 30 days a year when local and system peaks are expected to strain the wires.