Musk unveiled the Powerwall home battery in April 2015 at Tesla's design studio in Hawthorne, California, describing a vision of homes storing solar energy generated during the day for use at night, or drawing cheaper off-peak grid electricity for use during expensive peak hours.[1][2] The product has gone through several generations — Powerwall, Powerwall 2, and Powerwall 3 — each improving capacity, power output and installation simplicity, with Tesla later adding a backup-only leasing option to lower the up-front cost of adoption.[2][3]
01
At a Glance
Tesla Energy is the division of Tesla that designs and sells battery-storage products: Powerwall for homes, Powerpack for commercial sites, and Megapack for utility-scale grid storage. Musk unveiled Powerwall in April 2015 as a way to store solar energy or grid power for use during outages or peak-price periods, and Tesla later scaled the same underlying technology up to Megapack, a shipping-container-sized unit for grid operators and renewable-energy projects. Energy storage has become one of Tesla's fastest-growing and highest-margin businesses, with 2025 deployments reaching a record 46.7 gigawatt-hours, up 49% from the prior year, even as the company's core vehicle business faced a sales decline.
02
Powerwall: Batteries for the Home
03
From Powerpack to Megapack
Tesla initially offered a commercial-scale product called Powerpack before introducing Megapack in 2019, a much larger, pre-integrated battery system designed for utility companies and large renewable-energy projects rather than individual businesses.[1][3] A single Megapack unit can store several megawatt-hours of energy, and projects typically deploy dozens or hundreds of units together to back up or replace fossil-fuel "peaker" plants that would otherwise run briefly during periods of high electricity demand.[3][4]
Tesla introduced Megapack 3 in 2026, offering roughly 28% more energy capacity per unit than its predecessor, and began production at a dedicated new factory near Brookshire, Texas, adding to existing Megapack manufacturing capacity in Lathrop, California and Shanghai.[4][5]
04
Record Growth and Its Role in Tesla's Business
Energy storage deployments have grown sharply: Tesla deployed 14.2 gigawatt-hours of storage in the fourth quarter of 2025 alone and 46.7 gigawatt-hours for the full year, up 29% and 49% respectively from the prior year's comparable periods.[6][7] The energy division posted record gross profit and margins for five consecutive quarters through early 2026, at a time when Tesla's core automotive revenue was declining — making energy storage an increasingly important part of the company's overall financial picture.[6][7]
Notable large orders have included SpaceX itself, which purchased $329 million worth of Tesla Megapacks in a single year to power its own facilities and data centers, illustrating how Tesla's energy and space businesses have begun to intersect commercially.[7]
05
References
- 1Tesla, Powerwall, accessed on September 26, 2026.
- 2Tesla, Megapack, accessed on September 26, 2026.
- 3Tesla Investor Relations, Tesla, Inc. investor information and filings, accessed on September 26, 2026.
- 4Energy-Storage.News, Tesla reports record energy storage deployments and profit ahead of vote on Musk's monster pay proposal, accessed on September 26, 2026.
- 5Renewables Now, Tesla's 2025 energy storage deployments hit all-time high of 46.7 GWh, accessed on September 26, 2026.
- 6All Things Elon, Tesla Starts Megapack 3 Production With 28% More Energy, accessed on September 26, 2026.
- 7All Things Elon, SpaceX Has Bought $329 Million in Tesla Megapacks This Year, accessed on September 26, 2026.
06
Frequently Asked Questions
What is Tesla Powerwall?
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A home battery, unveiled in 2015, that stores solar or grid electricity for use during outages or expensive peak-price periods.
What is Tesla Megapack?
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A large, pre-integrated battery system for utility companies and renewable-energy projects, introduced in 2019, with each unit storing several megawatt-hours of energy.
How much energy storage did Tesla deploy in 2025?
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A record 46.7 gigawatt-hours for the full year, up 49% from 2024, including a record 14.2 gigawatt-hours in the fourth quarter alone.
Is Tesla's energy business profitable?
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Yes, and increasingly so. The energy division posted record gross profit and margins for five consecutive quarters through early 2026, even as Tesla's core vehicle revenue declined.
Does SpaceX use Tesla batteries?
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Yes. SpaceX purchased about $329 million worth of Tesla Megapacks in a single year to power its own facilities and data centers, including Colossus in Memphis.