"Tesla has launched a new virtual power plant in partnership with PG&E in California that will pay Powerwalls owners to help stabilize the electric grid and end brownouts in California," reports Electrek. A virtual power plant (VPP) consists of distributed energy storage systems, like Tesla Powerwalls, used in concert to provide grid services and avoid the use of polluting and expensive peaker power plants.
PC Magazine notes the program was launched in conjunction with California power utility Pacific Gas and Electric Company: As well as the personal feeling of satisfaction for helping to stabilize California's grid, you'll receive $2 for every additional kilowatt-hour delivered during designated "events," such as any time grid operator CAISO issues an energy alert, warning, or emergency. Contributors will receive push notifications before and during an event with details of its expected start and finish times. Once an event is over, each Powerwall will automatically resume normal operation. Electrek adds that "The $2 per kWh amount is quite significant and reflects just how much value a Virtual Power Plant can add to the grid in case of an emergency event where the grid needs more capacity. Depending on the events and the number of Powerwalls homeowners have, they could earn anywhere from $10 to $60 per event or even more for bigger systems." But in addition, "Tesla will dispatch your Powerwall when the grid is in critical need of additional power. That is when the least efficient generators would typically come online."

The largest distributed battery in the world could be over 50,000 Powerwalls. There are about 50,000 Powerwalls that could be eligible for this VPP, which adds up to 500 MWh of energy capacity. The company will be turned into a major electric utility. In Australia, it's already in use. It will be in Texas soon.