One of Tesla's big battery buyers is another Musk company. xAI, now part of SpaceX, bought another $269 million of Tesla Megapacks this year, after $430 million of purchases in 2025, Electrek reported on Wednesday, Oct. 21, 2026, alongside Tesla's Q3 results. Tesla says storage demand is at its "highest-ever order rate and backlog," driven by data centers.
Tariffs keep moving the energy numbers
- Energy gross margin by quarter, per Electrek: 31.4% (Q3 2025), 28.6% (Q4 2025), 39.5% (Q1 2026), 20.4% (Q2 2026) and 33.1% (Q3 2026).
- On the call, CFO Vaibhav Taneja attributed the Q3 jump "primarily" to "tariff refunds recognized in the quarter and warranty true-downs" from an agreement with a vendor to reimburse certain cell-related costs.
- Tesla's letter blames lower energy revenue "partially" on "tariff-related customer refunds" without giving an amount. Electrek said the likeliest reading is refunds tied to the IEEPA tariffs the Supreme Court struck down in February, but noted Tesla has not explained them.
- Taneja said "the money that we received from the tariff refunds is being reinvested to expand production capacity in the U.S."
- Energy gross profit fell to $954 million from $1.07 billion a year earlier, and Q3 deployments of 13.7 GWh were short of the roughly 15.9 GWh analysts expected, Electrek said.
Musk said on the call that Tesla is "almost sold out of all Megapacks for 2027" and expects margins on them "to increase meaningfully." Related: Megafactory Texas starts production and Tesla's full Q3 2026 results.