Tesla Starts Megapack 3 Production at New Texas Megafactory

What happened

Tesla confirmed that its Brookshire, Texas Megafactory began producing Megapack 3 grid batteries, 16 months after groundbreaking. The facility is designed to manufacture 50 GWh of Megapack 3 annually, representing Tesla's third grid-battery production site alongside facilities in Lathrop, California and Shanghai. Each Megapack 3 unit holds approximately 5 MWh of energy, up from 3.9 MWh in the Megapack 2 XL, achieving 28% more storage capacity in the same physical footprint. Tesla accomplished this increase primarily through larger 2.8-liter cell format and a redesigned thermal system that reduces connection points by 78%, improving reliability and reducing assembly complexity. The company also introduced the Megablock configuration, which bundles up to four Megapack 3 units (about 20 MWh) with integrated transformers and switchgear. By moving medium-voltage wiring work from field installation to factory assembly, Tesla says deployment can reach 248 MWh per acre with installation running approximately 23% faster than previous methods, enabling 1 GWh deployment in 20 business days. The Brookshire facility received approximately $44 million for building improvements and $150 million for manufacturing equipment under a local tax-abatement agreement, with potential for around 1,500 jobs.

Why it matters

The production start at Brookshire significantly expands Tesla's energy storage manufacturing capacity at a time when its storage business is growing faster and delivering higher margins than its core vehicle business. Tesla deployed a record 13.5 GWh of storage products in the second quarter, up 41% year-over-year, compared to 25% growth in vehicle deliveries. Energy generation and storage revenue reached $3.14 billion with a gross margin of 20.4%, exceeding the automotive segment's 16.9% margin. The higher energy density and faster installation capability of Megapack 3 address key bottlenecks in grid-battery deployment, where projects often stall on interconnection, permitting, and field construction rather than cell technology. Tesla recently signed a $5 billion, 25 GWh Megapack deal with NatPower in Europe, and demand from data-center operators continues to accelerate. At 50 GWh annual capacity, Brookshire alone could potentially exceed Tesla's entire Lathrop output, positioning the company to capture more of the rapidly expanding grid-storage market as utilities and renewable developers add battery capacity. The U.S. Energy Information Administration expects developers to add 24 gigawatts of utility-scale battery storage nationwide in 2026, with Texas accounting for 12.9 GW or 53% of the total.

Bigger picture

Grid-scale battery storage is emerging as one of the fastest-growing segments of the clean-energy transition, driven by increasing renewable generation, rising electricity demand from data centers, and grid-reliability concerns. The shift to factory-integrated medium-voltage equipment represents a broader industry trend toward simplifying field installation, which has been a major cost and timeline bottleneck. Tesla faces intensifying competition from established players including CATL, Fluence, and BYD, making manufacturing speed and unit economics increasingly important. The company has reported lower gross margins on energy products due to high tariffs on imported LFP cells, and filling a 50 GWh factory will require securing adequate cell supply amid evolving U.S. trade policy. Electricity rates rose nearly 10% in the past year and are expected to continue climbing, strengthening the economic case for both utility-scale and distributed storage. Tesla is also reportedly planning solar-panel manufacturing at the same Brookshire campus, which could create vertical integration opportunities between solar generation and battery storage, though the company has not confirmed investment figures or production targets for that facility.

What to watch

Monitor Tesla's quarterly energy deployment figures and gross margins to assess whether Brookshire output translates into higher volumes and profitability. Watch for announcements on cell-supply agreements, particularly for large-format LFP cells needed to reach the facility's 50 GWh design capacity. Track Megablock adoption rates among utility and data-center customers as an indicator of whether the integrated-equipment approach delivers the promised installation-speed advantages. Pay attention to competitive pricing and capacity announcements from CATL, Fluence, and BYD as the grid-storage market expands. Also watch for updates on Tesla's potential solar-manufacturing plans at the Brookshire campus, which could create synergies with battery production. Finally, follow U.S. tariff policy developments, as changes to import duties on battery components could materially impact energy-segment margins.