Battery energy storage system integrator Fluence Energy has cut its 2026 revenue forecast by $600 million after automated welding problems disrupted production at a contract manufacturing facility in Houston, Texas.
The Nasdaq-listed company now expects revenue of about $2.4 billion, down from its previous guidance midpoint of $3 billion. Its forecast adjusted EBITDA loss has widened from approximately $10 million to $200 million.
Fluence said more than 80% of the anticipated revenue reduction was attributable to US production problems, principally delays in ramping up the Houston facility.
The affected operation is a contract manufacturing facility where enclosures for Fluence’s storage products are welded and the products undergo final assembly. Fluence is the facility’s off-taker rather than its owner.
Fluence told investors that the contractor was the company’s established enclosure supplier in Vietnam. The company has previously identified that manufacturing partner as ACE Engineering.
The facility is separate from Bergstrom’s Houston operation, which produces thermal-management systems, including heating, ventilation and air-conditioning and chiller equipment, for Fluence’s Gridstack Pro battery energy storage systems.
Fluence CEO Julian Nebreda told investors the company had underestimated the complexity of ramping up production. A customised automated welding process was operating significantly below its target, while final assembly was being constrained by a shortage of skilled labour.
Production averaged fewer than one unit per day during August, compared with the 11 units per day assumed in the company’s previous guidance. Output increased to an average of three units per day during the first two weeks of September.
The contract manufacturer has temporarily moved to manual welding, recruited additional skilled workers and engaged three subcontractors in the Houston area to increase welding and assembly capacity. Fluence estimated these measures would add $25 million to costs.
Nebreda said the automated welding system was still being trained to weld the company’s Gridstack Pro 5000 equipment. A plan for delivering Fluence’s 2027 backlog had been prepared on the assumption that manual welding might continue, although it would be slower and more expensive.
The company has $2.9 billion of backlog scheduled for 2027, of which $1.2 billion requires US production.
The Houston plant has also not yet been connected to the electricity grid. Fluence said generators had been installed and power availability was no longer constraining output. Grid connection is expected in the first quarter of its 2027 financial year.
Nebreda said the delay in introducing manual welding had accounted for most of a roughly $1 billion shortfall against Fluence’s earlier annual revenue expectations.
“That is clearly not a resilient plan,” he said, adding that Fluence would seek to reduce its dependence on individual suppliers and manufacturing processes.
Law firm Hagens Berman has opened an investigation into whether Fluence adequately disclosed the facility’s operational readiness and potential financial effect. The announcement concerns a preliminary investigation and does not establish that Fluence or its executives violated securities law.
Fluence shares fell $1.39, or 15.4%, from $9.05 to $7.66 following the revised guidance.
The company also terminated chief product officer Peter Williams on 11 September and appointed former AES executive Bernerd Da Santos as chief operating officer. Da Santos will oversee product, supply chain, manufacturing, customer success and enterprise operations.
Correction — 24 September 2026: An earlier version of this article incorrectly linked the production problems at Fluence’s Houston enclosure and final-assembly facility to Bergstrom. Bergstrom is associated with a separate Houston facility producing HVAC and chiller equipment for Fluence. The affected operation is a contract manufacturing facility used for enclosure welding and final assembly.
