Dan Shugar, CEO of NEXTracker, is one of the old-school players in the rise of solar in the United States — he lives and breathes solar trackers.
pv magazine interviewed Shugar, took a tour of the firm’s tracker demonstration field and played some blues with the CEO. (Shugar’s a musician, I’m not.)
While single-axis trackers for solar panels might seem a bit mundane compared to a solar panel or an inverter, once you stumble into Shugar’s reality distortion field, trackers become kind of, well, sexy.
According to Wood Mackenzie, the tracker market grew 62 percent in 2019, reaching 23 gigawatts (DC) of installations — and the market will grow on average by 11 percent annually from 2019 through 2024.
According to WoodMac, NEXTracker is the world’s leading tracker vendor, with one-third of the market by shipments in 2018. Other firms claim between 8 percent and 12 percent of the market each, including Array Technologies, PV Hardware, Arctech Solar and Soltec.
The interview has been edited and condensed.
pv magazine: Talk a little about innovation. How much more performance can you extract from trackers?
Dan Shugar: There’s a lot more to wring out of this. There is definitely room for improvement. We focus on the integrated power plant and how the modules work with the tracker and the control system, how we respond to weather.
Since we launched the tracker, seven-ish years ago, we’ve been focused on yield.
pv magazine: Does that include working on tracking bifacial panels?
Dan Shugar: We were driving bifacial here from the get-go. I got exposed to bifacial and did the first bifacial installation with the Nellis project – 12 years ago.
The Nellis system was 20% bifacial, which was the most we could get. That used Sanyo HIT technology. We had really spent a lot of energy on bifacial 12 to 15 years ago. And, so understanding what the potential was for yield — with bifacial you really want to be on a tracker.
We had designed a tracker, the one actually deployed in Nellis, which was optimized around bi-facial — the T20 tracker.
I thought that installation was gorgeous. But the issue was that Sanyo had a very expensive technology, their HIT technology. It had a really small cell and they were just an expensive producer. We were begging them for product, and we took as much as they’d ship, but they couldn’t scale. Sanyo ended up selling to Panasonic.
The history, the context, was that the Chinese had scaled with traditional multi-screen print stuff, which is inherently not bifacial. The industry was quite static in terms of monocrystalline silicon.
But the quality of the material was really improving in terms of purity, the silicon had less defects, and driven mostly by Longi and a couple of others, we saw a huge shift back to multi. The thinning of the wafers, the shift back to multi and then some additional processing with the PERC meant there was little additional cost to make the cells bifacial — you just need to do a couple of additional processing steps.
pv magazine: But using bifacial changes the tracker math.
Dan Shugar: Now that the cells are increasingly bifacial, the yield you get is a function of how more granulated you spread out the material, the more reflected light you can capture.
What you want to do is find the idealized situation with regards to ground cover ratio. Typical utility-scale systems in the tracker realm, are say 35% to 40% ground cover ratio, some more, some less, but that’s a typical rate. With fixed systems, typically you’ve planned at 65% or 70% ground cover ratio. There’s a lot less reflected light.
And, secondly, the way fixed systems are oriented, you’ll have two or three or four modules that are together. So, you have a big white umbrella, it’s super dark in the middle. Whereas, if you granulated all these panels out, you would capture more of the reflected light.
And, so a tracker, because it’s one typically one panel wide, sometimes two, but not more than that — it’s the idealized framework in which to capture bifacial yield.
pv magazine: So is bifacial the best way to improve the value of tracking?
Dan Shugar: There are a couple of things that make the economics for a tracker way better. One is bifacial. Two is that the efficiency of the panels has gone up a hell of a lot due to a couple of things.
If you went back 12, 15 years ago, you got like three or four amps out of a cell like this. Now you have a bigger cell, and it’s way more efficient. You might be at like eight amps or 10 amps out of the cell. But, the losses inside the solar panel are the current squared times the voltage.
The expedient thing that a lot of people are doing is you cut the cell in half, and then you build these modules, and the current drops by half and the loss has dropped by a factor of four, and then you can thin out the amount of silver on this cell, the screen print. You obscure less of the cell.
Module efficiency has gone up a lot from better materials and processing, mono PERC and half-cut and as a result — on a tracker, the dollar per watt has gone down a lot, but the module power’s gone up a lot. The dollar per module has been much more stable, you’re getting a lot of watts you still want to track. If you need to get the backside, you have to track.
pv magazine: You talked about backtracking and better software 30 years ago, right?
Dan Shugar: Exactly. In 1991, we published the original backtracking algorithm with my colleagues at PG&E.
The whole industry went to that. Backtracking, if you had a perfectly flat, perfectly installed, perfectly sunny site, backtracking is the perfect way to track, but the real world is not that. If you have a site that undulates, you go up a hill, and the sun in the morning is over there, the trackers that are facing downhill east are doing great, the trackers on the west are hosed.
What happens is the system gets sort of de-tuned to the lowest common denominator. Depending on how undulating the site is, that could be up an over 4% annualized energy hit.
The second factor is on a diffuse day, like today, a traditional tracker will be at an angle, but if you go to horizontal, you’ll see the absolute power in real time go up by 10% to 15%.
On an annualized basis, by adaptively tracking to the optimized weather conditions in real time, not just keeping the sun perpendicular to the panel based on an astronomical clock — if you modify that, that’s another 2 or 3 percent, depending on the location.
pv magazine: That’s your True Capture software?
Dan Shugar: True Capture is dealing with the backtracking as well as optimizing.
It’s your individual row backtracking. Each row understands its geospatial position relative to its neighbor. One tracker knows where the next tracker is.
We commercialized linked-row systems back in the day. We didn’t invent the idea, but we sure as hell commercialized it.
We had actually developed an individual tracker, but the cost effectiveness of the control or technology wasn’t there yet, it wasn’t digitized.
pv magazine: The wireless technology at the time…
Dan Shugar: It wasn’t available.
Dan Shugar: We’ve built hundreds of these linked row trackers, and that was fine. That was a decent technology back 20 years ago, but it couldn’t do adaptive tracking. This is a huge thing. We can get as much as as 2% to 6% more energy depending on the site, and that’s unbelievably powerful. These are additives — so you have the bifacial gain, you have the true capture gain. These are all additive to what you’d have with a fixed system.
There’s other things you get out of this. I was meeting with a client yesterday. They have a bunch of fixed systems at a low angle. It snows and the snow stays on there. They lose a ton of production. It could be another 3% improvement. Our tracker goes 60 degrees and so the snow slides off. We’ve developed custom algorithms we call Snow Shed, where they’ll tilt and dump the snow mid-morning and mid-afternoon. All this additive yield adds up.
pv magazine: NEXTracker was acquired by Flex a few years ago. You’ve been through an acquisition before with PowerLight and you have experience in this. Can you tell us about this most recent adventure in integrating a company into a much larger entity?
Dan Shugar: As you said, it wasn’t our first rodeo and that informed how we structured the deal when it actually went down. I was really clear with the CEO of Flex when we did the merger that we needed to be a wholly owned subsidiary, but also a separate company, a separate brand, and I needed to run the P&L with a lot of autonomy. They agreed to that.
You see that manifested. We’re in a separate building. We have a completely separate culture. We have our pet-friendly side, and their non-pet friendly side. At a high level I’d say it’s gone extraordinarily well. I would say if you look at a distribution of goodness, how mergers are going, we’re on the tail end of goodness.
There are public companies, so there’s some certain things that must be integrated like basic processes.
But, for the most part, we really run the operation. When we need support, we’ve gotten it. The thing that has been really helpful, one of the reasons we did the merger, is that we wanted to bring our technology into far away places that can be challenging to serve, like Brazil, India, places like that.
Flex has over 12,000 people in both of those countries. We can go in there and operate through their existing legal company. We’re still NEXTracker, but the way the actual money flows is through an existing legal entity. Flex can worry about things like global treasury optimization, things like that. We have great customer focus and solar design, product focus and operational focus in solar. We don’t necessarily want to be global experts in…
pv magazine: Currency exchanges, yes?
Dan Shugar: Exactly. Those kinds of things, like hedging.
pv magazine: It allows you to be an international company with less investments in infrastructure
Dan Shugar: Exactly. It’s worked really well. You’ve seen, we’ve grown. We have 24 operating projects in India, and we’ve gotten fully paid and those have been really great. We’ve got a bunch of projects operating in Brazil. That’s a tough place to do business. It’s got its own unique set of rules. I think this has worked extremely well. The one piece that Flex actually manufacturers for us in a Flex factory, which is really important, is the controller.
pv magazine: That makes sense, that’s their strength, yes? Circuit boards and metal bending?
Dan Shugar: Sure. These power plants have gone from a megawatt to a gigawatt level. If you’re building power plants that are $250 million, $500 million, a billion dollars of value, you need it properly designed. We got that. The controller is really important.
As you know, the volatility in PV is high. If you look 10 years ago at the tracker companies — who is still around? Even the big guys have gotten out of it. SunPower’s gotten out, FirstSolar has gotten out of it, Sunlink went belly up, another tracker company is on the rocks right now.
We’re getting calls from a lot of clients saying, hey, could we make our controller for other companies? My point is we’ve got the best possible provider with Flex. They have a 230,000 person company and $25 billion in revenue.
We’ve seen owners really focusing more on a flight to quality, rather than going with the cheapest setting. So in more mature markets, that’s the trend.
pv magazine: A colleague asks if there’s a tool for smaller projects, say a few megawatts, that a developer can use to build their own systems and get rough pricing on? Your company is not going to look at a sub-one megawatt project, I assume. Is there a tool that he can look at to consider whether he should incorporate trackers?
Dan Shugar: First of all, we support the whole idea of distributed generation. Early in my career at PG&E, we published a lot on grid support and how small systems benefit the grid. Psychically, we believe in lots of distributed systems. Five years ago we created a separate division to really support DG. We had hundreds of small DG systems out there in the 1 to 10 megawatt range.
In order for us to effectively serve that, we have a couple of partners that are regional, that are really good at supporting the smaller developers.
In the case of your colleague, if he said, “Hey, I’ve got a portfolio of 3 to 5 jobs in this small range,” we would refer him. We’d say “yeah, our technology is perfect for it” in terms of efficiently supporting his opportunities where we’d refer him to one of our partners that knows how to install our system, how to procure it. That partner would also provide installation services to the extent that’s needed by the developer.
We psychically want to support that part of the market. We think trackers have a huge role to play and, personally, I’m really excited about community energy and more DG.
We’ll cover the terror of torsional galloping in a solar array and NEXTracker’s training facility in part two of our interview with Dan Shugar.