September 15, 2026: Base’s battery lineup expands, but the big questions stay open

September 15, 2026, and Base Power’s latest public documents point to a broader product stack, but not yet to a meaningfully different operating picture.

The clearest update is in Base’s help center. Base now says it offers 25 kilowatt-hour, 39.2 kilowatt-hour, and 50 kilowatt-hour battery systems, all paired with an 11 kilowatt inverter. It also says the 39.2 kilowatt-hour unit is its newest battery and is still in limited beta in select areas. That is a company claim, not independent proof of how widely the new unit is deployed, but it does suggest Base is no longer describing a single static system.

On the commercial side, Base’s Core page still advertises the same basic offer structure: 39.2 kilowatt-hours, 13.9 cents per kilowatt-hour Oncor pricing, a 695 dollar install fee, and 19 dollars per month membership. The page also now says Core is in production at Base Factory 1 in Austin. That production language is important, but it remains a company claim until outside records show output, commissioning, or other independent factory evidence.

Base’s electricity facts label page also still organizes plans by utility territory, including Oncor, CenterPoint, AEP Central, AEP North, and TNMP. It says the utility supply price to compare is 10.399 cents per kilowatt-hour through September 30, 2026. That comparison benchmark matters because Texas retail offers are often judged against the local utility’s supply price to compare. If that benchmark resets or expires, the same plan can look cheaper or pricier on paper even when the product itself does not change.

That is the main plain-language mechanic to keep in mind today. The price-to-compare is a reference point, not a guarantee of what a household will pay. So when Base, or any retailer, shows a rate next to it, the comparison can shift simply because the benchmark changed. That is why the September 30 expiration date on Base’s posted comparison price is worth watching.

What did not change is just as important. ERCOT’s ADER pilot still sets the gate for wholesale participation around a resource that can, in aggregate, respond to ERCOT dispatch instructions. That is the unresolved market proof point for Base. Until there is a filed ERCOT or PUCT record naming Base resources, qualified megawatts, telemetry validation, or dispatched services, wholesale participation should stay in the unresolved column.

The same caution applies to the factory story. Base says Factory 1 is producing, but today’s research dossier does not include a certificate of occupancy, electrical final, commissioning record, or interconnection completion tied to the facility. So the correct reading is partial progress, not verified scale-up.

There is also no new grounded evidence here on reliability, recalls, or customer complaint patterns. The open reliability question still needs failure-rate metrics, warranty disclosures, RMAs, recalls, or supplier corrective-action notices before anyone can say more than unknown. And on the complaint side, the only responsible stance is still that the signal is unknown until a Base-specific row or trend change appears in the PUCT complaint statistics page.

One item in the background remains just that, background. The Information reported that Base is in talks to raise funds at a 12 billion dollar valuation, with Ribbit Capital possibly leading. That would be a major capital step if it closed, but today it is still rumor, not a completed financing. No one should treat that report as revenue, operating proof, or a closed round.

So the practical story for September 15 is modest but real. Base’s public materials now show a more segmented battery lineup, including a new unit still in limited beta. Its pricing pages remain stable. Its factory claim is still unverified externally. And its wholesale market ambitions remain stuck at the level of an unresolved qualification question.

If you are tracking Base day to day, the next falsifiable checkpoints are straightforward. First, does Base publish any independent factory evidence, such as an occupancy, electrical, or commissioning record for Factory 1? Second, does ERCOT or the PUCT file anything that names Base resources in ADER, with qualified capacity or dispatched performance? Third, does the September 30 price-to-compare figure roll over, and if so, what does Base post afterward? And fourth, do any complaint statistics, recalls, or warranty records turn from unknown into a measurable trend?

Until one of those shows up, the best read is that Base is still refining product and public presentation faster than it is proving the harder parts of scale.