Solar Builder

MAY-JUN 2018

Solar Builder focuses on the installation/construction of solar PV systems. We cover the latest PV technology (modules, mounting, inverters, storage, BOS) and equip installers/contractors with tips and tools to make informed purchasing decisions.

Issue link:

Contents of this Issue


Page 29 of 55

30 M AY / J U N E 2 0 1 8 B eing the No. 1 tracker world- wide according to GTM Research, I will assume you've heard of NEXTracker and its decentralized tracker design by now. What you may not know about is the company's giant leap into the storage arena with two solutions — NX Drive, a standardized bat- tery enclosure system for generation-plus- storage or stand-alone storage applications, and NX Flow, a modular, integrated solu- tion designed for long duration solar-plus- storage applications. NX Flow in particular intrigued us. It's a solution so unique the company worked on and created a new UL standard to test for and prove what it does (more on that later). We stopped by the Fremont, Calif., offices to record a Solar Builder Buzz podcast with Chief Technology Officer Alex Au to dis- cuss the concept, maximizing MWh over pure MW, decapitating the duck curve and the effect tariffs might have on all of this. Be sure to download the full podcast interview (and subscribe!), but here are three big takeaways. 1. The NEXTracker NX F low is a 30-kW tracker row with a battery coupled just to that row, making it a modular power plant that achieves a renewable base load. There are two keys to its value proposition. One is the battery. Au: "Two years ago we started an RFP called 'Decapitate the Duck' specifically to address the storage market. We reviewed north of 40 technologies. We had an aggressive demand profile, tested units and agreed to move forward with the Avalon battery — a vanadium flow battery. As of Christmas last year, we were able to pass the point of 10 years worth of cycles. Approximately 1.25 cycles per day, 100 percent depth of discharge. We haven't been able to detect any degradation. With other batteries there are maintenance cycles and equalization time, but we haven't had to do any of that either. "The Avalon product mates perfectly with one of our 30-kW rows; it is a 6,000 -lb unit, can ship completely wet and has actually gone through a burn-in cycle in the factory. That testing and burn-in period means you literally just plug in the DC wires for the modules and then the AC grid. Takes less than an hour and 15 minutes to do the full installation with piers and everything." Alex Au [right] explains to a dummy [me] how NEXTracker's NX Flow achieves a renewable energy base load. MOUNTING G U I D E Curve Stomped How NEXTracker's tracker-plus-storage strategy eliminates the duck curve By Chris Crowell

Articles in this issue

Archives of this issue

view archives of Solar Builder - MAY-JUN 2018