As the cost of solar photovoltaic modules becomes an increasingly smaller piece of the "all-in" price, balance of system (BoS) has become a more prominent piece of the puzzle, subject to cost pressure as well as innovation. GTM's Solar Summit featured several panels on BoS, ranging from electronics to cables to mounting to racks and trackers.

The conversations were occasionally heated, especially when microinverter maker Enphase and panel optimizer firm Tigo faced off. (Despite the protestations of an audience member to play nice.) SolarBridge, which builds a microinverter focused on full panel integration to create an AC module (ACM), also weighed in, but avoided the Enphase-Tigo slap-fight.

Jeff Krisa, VP of Marketing at Tigo, said that Tigo and Enphase were founded around the same value of distributed electronics. Tigo, according to Krisa, "took a different approach at delivering these features." Krisa said the distributed electronics in the Tigo architecture "lowers the LCOE in all cases." "Something we do is focus on delivery of data and analytics, lowering the risk of the plant and lowering the O&M." He suggested that although Enphase has "had some success in the long tail," the challenge is always this: how do you convince a guy in Germany  to do something differently? Krisa noted that "we're close" and that traditional installers as well as financiers are beginning to understand the value of distributed power electronics. Krisa also remarked that the individual panel visibility enabled by the company's approach was a feature that was moving from "monitoring" to "asset management."

Bill Rossi, CMO of newly public Enphase, noted that he was new to the solar industry and his two years of PV experience have left him less cynical than many of the veterans in the crowd. Rossi reported that Enphase has shipped 1.7 million units so far and added, "It's not just happening in residential." Rossi said that 30 percent of the company's business is in commercial installs.

On Tigo, Rossi suggested that the company's optimizer was a classic "tweener" technology -- not an inverter and not a microinverter -- and the market doesn't understand it. This is not the first time Enphase has questioned the value of the Tigo-style optimizer architecture.  

Rossi also argued that the California Solar Initiative (CSI) database indicated that the price of Enphase's all-in installs were at or less than the cost of traditional installs. Asked if Enphase could ever reach the cost per watt of string inverters, Rossi said that Enphase was fundamentally a semiconductor company with an ASIC at the heart of the product -- and therefore the dollar-per-watt metric will come down much faster in the microinverter than in the string inverter sector.

Craig Lawrence, VP of Marketing at SolarBridge, made the case for SolarBridge's AC module (ACM) approach. Lawrence argued that truly integrated AC modules better enabled the 10X growth of the solar business by simplifying the design process, allowing larger installations, and opening up a wider workforce to be trained up to address volume roofs. As for SMA and Power-One's entrance into the microinverter market, Lawrence posed the question of whether an entrenched incumbent concerned with cannibalizing its existing business can compete with a laser-focused startup doing one thing really well.

All three of these firms are collecting massive amounts of module-level performance data, which might eventually serve a yet-unmined purpose.

In any case, the market will determine the winner of these different approaches, and for the moment, Enphase is very much in the lead.  

Another take on panel-integrated solar electronics is tenKsolar's solar panel construction, which mates a wavelength-selective reflector to an "illumination-agnostic solar panel." The panel's novel wiring scheme and redundant electronics within the panel itself allow light to strike the panel in a non-uniform fashion -- without sacrificing power harvest. Innovations in PV-cell-to-PV-cell interconnections ensure no single point of failure, according to Dallas Meyer, the CTO and Founder of tenKsolar. Meyer claims, "We're talking 30 percent to 40 percent advantage in power harvesting" and a far better LCOE.

TenKsolar just closed a $15.5 million funding round from Hanwha of South Korea joined by ESB Novusmodus.


Another panel at the Solar Summit addressed even more BoS technologies:

Dean Solon, CEO and Founder of Shoals Technologies Group, told the great story of how his firm moved from automotive components to solar harnesses, junction boxes, combiner boxes, and other solar BoS componentry and into position as a supplier to First Solar, Tigo, and SolarEdge. The CEO remarked that "people ask us to do stupid things and we can do stupid things all day long. Except modules."

John Rethans, Director of Product Management, Solon Corporation (now owned by Microsol) reported on its new racking product that uses a material called Fibrex made by the Andersen company, a venerable maker of windows and doors. The material is new to the solar market, but it has been on the market for 50 years in demanding outdoor building applications. Moderator Stephen Smith of Solvida Energy Group suggested that solar would be well served by pulling technologies and practices from other industries.
Laurence Mackler, CEO of Solaire Generation, builds a set of turnkey solar parking and carport structures with an eye to aesthetics, functionality, and serviceability. The deployments range from the kilowatt-range to a 3.6-megawatt system deployed by Dow Jones.

Wasiq Bokhari, CEO and Founder of QBoTix, was a stealth developer of dual-axis tracking systems -- at least until this event, when he revealed that his firm is developing a dual-axis tracking system at single-axis prices. Bokhari claims that the new product can reduce LCOE by 10 percent to 15 percent with its innovation in controls and activators. It is designed to be compatible with all panels and inverters and looks to ship a few megawatts this year. The CEO also said that the product provided inherent redundancy and much higher reliability. We'll hear more from this firm in a few months, but Bokhari left us with this: "It's possible to reduce BoS without decreasing reliabilty."


The hope is that BoS performance and pricing can be driven down the same cost curve as solar modules, minus the harrowing financials seen in today's module business.