How much battery storage does CAISO have?

CAISO had approximately 250MW of storage resources connected to the grid as of late last year. CAISO believes that the amount of battery storage on its transmission system will increase four-fold between late last year and this summer, reaching 2,000MW by the beginning of August.

Why does CAISO not include battery charging?

One quirk of CAISO’s load reporting is that they do not include battery charging, which distorts the picture of total demand on the grid. To ameliorate this, we have added it back in the figure below, which dramatically alters the shape of the load curve for 2024.

Are CAISO batteries fully charged during a heat wave?

However, aggregate state-of-charge for the CAISO battery fleet tended to stay below 90 percent of total charge capacity (around 13,600 MWh) throughout the heat wave. Batteries would not be fully charged—even in the hours preceding peak load—as a result of any of the constraints listed in Section 3.1.

How long does CAISO's battery management feature last?

Originally, the CAISO intended this feature to be a stopgap measure to manage critical periods while refining rules for battery storage resources, and gave it a sunset date of two years after implementation.

Are batteries a major force impacting CAISO's grid operations?

Batteries have taken a huge leap forward in CAISO this spring, shifting from a noteworthy trend into a major force impacting operations of the grid Battery storage has been a standout performer in California ISO this spring. After years of growth, batteries have reached a level of operations where they now play a newly impactful role on the grid.

What happened to CAISO's solar load this April?

CAISO’s load has been low this April, with a relatively mild spring, the continued march of BTM solar installations, and energy efficiency upgrades. However, with changes to the state’s net-metering program, BTM solar growth has started to slow. All of the different generation sources we discussed so far are running with the goal of serving load.