Tesla has unveiled the Megablock, a next-generation utility-scale storage solution designed to set new benchmarks in efficiency, speed of deployment, and cost savings. Building on the success of its widely deployed Megapack systems, Megablock introduces a pre-engineered, medium-voltage architecture optimized for massive renewable energy projects worldwide.
Faster Deployment and Lower Costs
Announced at the company’s ‘Las Megas’ event in Las Vegas on Monday night, Tesla says the Megablock installs 23 percent faster than Megapack, with up to 40% lower construction costs thanks to its simplified design and reduced site complexity. Each block is engineered for 20 MWh of AC capacity, translating into a site-level energy density of 248 MWh per acre—a crucial advantage as utilities and developers seek to maximize output within limited land footprints.
Megablock pic.twitter.com/JqQEAv4grj
— Tesla (@Tesla) September 9, 2025
Proven Technology, Enhanced Design
The system leverages the latest Megapack 3 architecture, incorporating Tesla’s proven inverter technology and fire protection system. A drastically simplified thermal bay—with 78% fewer connections—improves reliability and reduces maintenance demands.
Tesla says Megablock will use its most advanced cell technology, sourced from the U.S., Southeast Asia, and China, with a targeted manufacturing capacity of 50 GWh per year.
Performance has also been a priority. Megablock offers a 91% round-trip efficiency at medium voltage (inclusive of auxiliary loads), with a lifespan rated for over 10,000 cycles across 25 years. Operating conditions are equally robust, with functionality guaranteed from -40°C to 60°C, ensuring deployment potential from arctic regions to desert environments.
Megablock will begin production at the company’s newest Megafactory in Houston, Texas in the second half of 2026, with the first deliveries to follow shortly thereafter.
From Megapack 2XL to Megablock
Before Megablock, Tesla’s flagship energy storage product was the Megapack 2XL, introduced in 2022 as an enhanced version of the original Megapack. The 2XL delivered up to 3.9 MWh of storage per unit, nearly doubling the capacity of the standard Megapack, while integrating improved thermal management and higher-density battery modules. It became the backbone of many of Tesla’s largest projects, from massive installations in California to grid-balancing deployments in Australia and Europe.
The 2XL helped Tesla’s energy division hit record highs in deployed storage, making it one of the fastest-growing segments of the company’s business.
Megablock represents the next logical step, scaling well beyond individual containerized units like the 2XL into pre-engineered blocks that streamline installation at the site level. Where Megapack 2XL pushed the limits of modular storage capacity, Megablock focuses on deployment efficiency, site density, and total system economics, marking a shift from maximizing per-unit energy to optimizing grid-scale buildouts.
You can watch the full Las Megas presentation below.
Presentation starts in 1h https://t.co/S4lTEzXDyg
— Tesla (@Tesla) September 9, 2025
