Tesla builds largest grid battery in US at xAI’s Memphis site

Seven hundred and twenty Tesla Megapacks, arranged across what used to be relatively quiet Memphis terrain, now form the single largest grid-connected battery system in the United States. Satellite imagery from July 11, 2026, confirmed the sheer footprint of the deployment at xAI’s Colossus 2 data center in Tennessee, a facility purpose-built to train cutting-edge AI models on hundreds of thousands of GPUs. The estimated storage capacity sits around 2.8 GWh, with some projections suggesting it could climb as high as 3.3 GWh. Depending on the specific Megapack model deployed, the system’s power output ranges from 720 MW to 1.4 GW. A billion-dollar battery habit Between 2024 and mid-2026, xAI and its parent company SpaceX funneled roughly $1 billion into Tesla Megapacks and related infrastructure. A single purchase in April 2026 alone was worth $269 million. SpaceX acquired xAI back in February 2026, consolidating Elon Musk’s AI ambitions under the same roof as his rocket company. Before the battery system reached its current scale, the Memphis facility leaned on temporary natural gas turbines to fill gaps in grid supply. Those turbines drew environmental criticism from local residen...