More than 2,000 households in South Australia have been given a $55 credit on their bill from Tesla after their PowerWall batteries helped keep the lights on earlier this month after a big storm caused major damage to the electricity grid.
The households – who all participate in a “virtual power plant” managed by Tesla and use its Powerwall 2 home battery system – have been advised of the $55 credit by Tesla on the app that monitors their electricity use, solar consumption and battery operations.
Batteries – both big and small – played a key role in the events on November 12, when a huge transmission tower collapsed in the middle of a major storm, tripping multiple circuits and causing South Australia to be “islanded” and lose its synchronous connection to the rest of the grid.
The batteries were important because they helped arrest the frequency excursion after the collapse of the tower and the separation.
Most of the response came from the original “Tesla big battery” at the Hornsdale Power Reserve, but also from the Dalrymple North battery, and the Tesla VPP, and also one run by AGL.
See also:Â Battery storage and big solar button keep lights on and dampen critics in South Australia
“Your Tesla Virtual Power Plant participation has helped maintain grid stability across South Australia this week during a significant grid event,” the notice to customers said on its app.
“We would like to thank you by providing an additional bill credit of $55 (incl GST) for each Powerwall you own. This bill credit will be applied to your Tesla Energy Plan account.”
The credit to households means the Tesla VPP will share at least some of the windfall profits it likely made from the event, when frequency and ancillary services costs soared and the market operator had to impose a price cap.
In a separate LinkedIn posting, Tesla noted the severe weather event caused South Australia to disconnect from the National Energy Market (NEM), resulting in blackouts that impacted tens of thousands of homes and businesses.
It should be noted that those blackouts, which affected more than 160,000 customers at its peak, were caused by local network problems, such as trees and branches on power lines and fallen poles, and not the separation event.
“Over 4,000 homes with Powerwall connected to Tesla’s Virtual Power Plants reacted within seconds to maintain grid stability across the state while keeping their homes powered,” the LinkedIn post says.
“Tesla’s battery storage played a significant role in helping to avoid the widespread events of 2016.”
The rebate applies only to those households connected via the Tesla Energy Plan, as opposed to other VPPs that also use Powerwall batteries. It is estimated that this will reward more than 2,000 customers who take part in Tesla’s VPP, which is sized at around 12MW.
The reference by Tesla in its LinkedIn post to 2016 refer to the system black in South Australia that was caused by a series of tornadoes that tore down three transmission lines and created a series of cascading events that caused the lights to go out across the state’s entire grid.
It had been speculated at the time that the presence of a big battery, or multiple small batteries, would have acted as a shock absorber and prevented some of those cascading events.
The political fallout and the grid response to the incident led to the quick construction of the Hornsdale battery – built in less than 100 days as promised by Tesla boss Elon Musk – and it has proved its worth by cushioning multiple separation events since then.
South Australia now has three big batteries in operation, the now expanded Hornsdale facility, and smaller batteries at Lake Bonney and Dalrymple North, and an estimated 50MW of distributed storage from batteries in households and businesses.
There are also several smaller batteries operated by the water utility, and a number of major new battery storage projects in construction and development, including the Blyth battery that will help deliver 24/7 renewable power to the giant Olympic Dam mine in the state’s north.
