In March, Elon Musk made a bet on Twitter that his company Tesla could, in just 100 days, build a 100 MW lithium ion battery system—bigger than any in the world—in South Australia. If Tesla failed to meet the deadline, Australia would get its money back, no questions asked.
Tesla came through, and after initial testing, the record-setting battery was switched on earlier this month. It was just in time, too, as South Australia’s brutal summers begin in December. In fact, within two weeks of going online, the Hornsdale Power Reserve battery system (as it’s officially called) was put to its first test. On Dec. 14, one of the coal-power units at Loy Yang, one of the biggest power stations in Australia tripped up, causing a sudden and massive drop of power—560 MW, enough to power some 170,000 Australian homes.
This was exactly the type of problem the Tesla battery was built to solve; the Twitter bet was made after Musk announced publicly that his batteries could solve South Australia’s chronic summer power-outage problems. Tesla passed with flying colors. In literally less than a blink of the eye—it happened so fast the Australian energy market regulator couldn’t time it—the Tesla battery, 620 miles (about 1,000 km) away from the coal plant, shot a 7 MW jolt of electricity into the grid, stopping the bleeding and starting the grid back on its way to recovery.
Then, on Dec. 22, it happened again: a different coal unit at Low Yang tripped, this time causing a 353 MW loss in capacity, and again, the Tesla battery came to the rescue, responding in milliseconds with a 16 MW injection to keep the grid under control.
Almost all grids have a backup power source contracted to sit dormant during periods of low-energy need, and kick into gear when needed. In most cases, these backups are…