A year ago, NEXTracker launched an innovative solar tracker with flow battery storage built into it. This December, the big new thing looks much more familiar.

The company has taken over a containerized lithium-ion storage product developed by parent company Flex, a major manufacturing firm active around the world. The NX Drive comes in conventional 20- and 40-foot container sizes, but it's a "highly engineered structure" that standardizes the system's electrical, mechanical, thermal and fire suppression needs, said NEXTracker CEO Dan Shugar.

The platform gives the customer a range of choices on battery chemistry and inverter architecture. It has already been installed in multiple locations, including a National Renewable Energy Laboratory test facility in Colorado, as well as customer sites that Shugar declined to disclose.

"Storage is happening, and it’s going to scale," he said. "We wanted to make it easy for customers to get involved and also have a really flexible design."

Many an integrator already sells containerized storage aspiring to the platonic ideal of "plug and play." As a newcomer to the field, NEXTracker hopes to leverage a few differentiators.

One is the digital asset management platform, ported over from the long-running solar tracker business. This system monitors equipment performance in the field, sending data back to NEXTracker via a ZigBee wireless mesh network.

For a battery system, that means moment-by-moment monitoring of temperature and cycling, which is crucial to maintaining the cell warranty and optimizing performance. The company backs up that data with "Fort Knox-level data security" supplied by Flex.

That corporate parent lends strength in the manufacturing arena, and in the global presence for sales and service, although the initial sales focus is the U.S.

"When NEXTracker takes on a supply chain, we don't mess around," Shugar said. "We have an amazing on-time delivery record. We’re approaching the battery market with the same fortitude."

The business pitch that highlights a corporate parent's global reach has become more popular among storage integrators this year. Now Greensmith can point to Wartsila, Green Charge can mention Engie, Younicos taps into Aggreko, and, if the paperwork ever goes through, AES Energy Storage will reach out through Siemens' 160-country sales team.

Simply having a parent company with deep pockets and global reach, then, doesn't differentiate as much as it used to. That said, NEXTracker's years of experience shipping and installing fields of utility-scale solar trackers will count as evidence of the company's logistical wherewithal.

Ultimately, the NX Drive looks and feels like storage solutions being sold by all sorts of companies. But NEXTracker hasn't given up on its wholly unique contribution to the storage market.

The NX Flow puts the flow battery right on the end of the solar tracker. (Photo credit: NEXTracker)

The NX Fusion Plus, announced last year, included vanadium flow battery systems from Avalon Battery attached to a solar tracker at the factory to allow for streamlined workflow and quality control.

NEXTracker pitched the combination as a way to avoid clipped power, which gets lost when generation exceeds the solar inverter’s capacity. The flow system is DC-coupled to the tracker with an Ideal Power inverter, and soaks up any power that would otherwise be clipped.

The system sounded good on paper, which left out the crucial question of whether anyone was ready to pay for it.

Hardly anybody buys flow batteries yet, despite many a lab scientist's assertions of their superior cycle life and safety. Ideal Power has commercialized promising power conversion technology, but is still a small-cap relative newcomer to the inverter world, and lacks the balance sheet of a SolarEdge or SMA.

The product doesn't appear to have flown off of the shelf. NEXTracker has installed some flow systems at customer sites, Shugar said, but he declined to say where or how much capacity they add up to.

Asked whether the product is ahead of its time, he said he heard the same skepticism when the company launched its independent row trackers, back before it became a market leader.

"There’s a period of specification and development," he said. "We’re going to see this coming year and the next year be breakout years for storage. We are very well positioned with a product that covers a wide range of use."

The only major update to the flow product appears to be a name change: It will henceforth be known as the NX Flow, to maintain a "consistent branding platform."