The UK product safety regulator published a report on the Tesla Powerwall 2 on 28 September 2026. The Office for Product Safety and Standards describes a fire risk in certain affected units rather than in every unit installed. Tesla has begun a replacement programme, and the questions a UK owner is left with are whether their unit is affected, what still works, who arranges the swap and who pays for it.

What the report says the fault is

The report describes an investigation that found battery cells made by a third party may contain excessive lithium plating. That plating can crack the cell casing, which can produce an internal short circuit and thermal runaway, and the report describes the result as an increased risk of the battery overheating and catching fire. The defect involves certain cells within affected units and may develop over time; the report does not describe a fault present in every Powerwall 2.

The report records the product as not meeting the requirements of the Electrical Equipment (Safety) Regulations 2016. The GOV.UK entry is a product safety report, and its measure type is a modification programme.

How an owner finds out whether a unit is affected

The regulator's instruction to owners is to keep the Powerwall 2 online and check the Tesla app for a notification confirming whether their unit is affected. That notification is the confirmation route the regulator publishes. Neither the report nor Tesla's UK replacement page publishes a serial number list or a count of affected units, so the government page on its own cannot tell an owner whether a particular unit is in scope. The report does not explain how to interpret a missing notification.

Solar keeps generating, backup does not

Solar generation continues during the programme, while backup power is unavailable until the replacement is installed. Tesla says this on its UK replacement page. Backup is the function that keeps a home powered during a grid outage, so that protection pauses with it. The report records that most affected units were discharged remotely, with technicians discharging the rest, and that the discharge happened pending replacement. Tesla states that a discharged unit no longer presents an operational risk. That statement is the company's own assessment of its equipment, and no independent verification is cited here.

Concept illustration of solar panels in daylight beside a storage battery marked with a pause symbol under SOLAR ≠ BACKUP.
Tesla says solar generation continues while battery backup is temporarily unavailable pending replacement. Concept illustration; no assurance of power during an outage.

Who arranges the replacement and who pays

The replacement is free of charge for affected units, the report says. Owners are directed to their original Tesla Certified Installer to arrange the installation. If that installer is unavailable, or asks for an additional payment, the published fallback is Tesla Support on +44 1628 450630. Tesla says affected customers are prioritised, and that once an installer has been in contact the company coordinates the removal and the installation.

Why no installation date is published

Neither document gives an installation date for a particular property. The published description is a sequence: the installer makes contact, then Tesla coordinates the removal and the installation. The two channels for status are the Tesla app and the installer.

What the report does not say about scope

The report names the Powerwall 2, described as an AC battery system for residential or light commercial use, and it does not mention the Powerwall 3. It refers to affected units rather than the whole installed base, so owning a Powerwall 2 does not by itself put a household in the programme. The risk level field on the GOV.UK page reads "not provided", so the publication does not grade the hazard. The report does not say how many units have been replaced so far. The notice is PSD notification 2609-0219, with Local Authority Trading Standards as the notifying authority.

What an owner can do next

Keep the unit online so the app notification and any remote work can reach it, watch the app for confirmation, and contact the original Tesla Certified Installer about the replacement. If that installer cannot help or wants to charge, the Tesla Support line is the published alternative. Nothing in either document asks an owner to open, move or service the battery: the discharge of the remaining units is described as work for Tesla technicians.