GreenVolts, a concentrating photovoltaic (CPV) supplier, came to the solar market with a lot of promise a few years ago -- only to recede soon afterward. The startup had signed a multi-megawatt power purchase agreement (PPA) with PG&E in 2008, one of the more sizable CPV projects at the time. But GreenVolts had some troubles and a bit of a boardroom shift: founder Bob Cart was replaced as CEO by JDSU executive Dave Gudmundson.

Gudmundson took the firm quiet and the company radically reworked its product and its strategy.

And now GreenVolts has returned, armed with a new design and a new $35 million VC round, which includes $20 million from ABB Technology Ventures, the VC arm of ABB, the power and automation technology giant. The GreenVolts CPV technology is a good match for ABB's recent equity stake in Novatec Solar, a provider of linear fresnel lenses. The round brings GreenVolts' VC fundraising total to more than $115 million since its founding in 2005.

While GreenVolts was re-inventing itself, Amonix, Soitec, and SolFocus became the dominant leaders in the CPV sub-sector, with hundreds of megawatts in their PPA pipelines

But Eric Romo, a VP and founder at the firm, doesn't see those CPV vendors as the competition. He told Greentech Media, "The competition isn't CPV, it's PV. How we measure and think about ourselves is as a solar company, not a CPV company." He adds that GreenVolts has won a dozen projects (about 3 megawatts total) in competitive bids against flat-panel photovoltaics.

Romo claims that CPV has "the potential to be the next leg in the curve," adding, "The next phase is showing CPV is not just as good, but better than PV." He acknowledges that if CPV vendors expect customers to pay more for CPV because of some of its advantages, such as its space-saving compact size, "That's just not going to happen."

According to the VP, "Everything about our CPV product has changed. Everything changed because we needed to get to the right price and performance. It had to be better than other PV solutions."

Romo emphasized, "We are a systems company."

The press release from the firm states that GreenVolts is "the industry’s first complete and fully integrated solar system, including modules, trackers, inverters, and energy management software." Although not willing to go on record, a competitor in the tightly knit CPV space told me that this was hardly a CPV industry first and that most CPV vendors provide complete systems.

What that "systems" claim is, really, is an attempt to find some or any differentiation for the GreenVolts product in a brutal, commodity electron market.

One of the things that is different for GreenVolts is the concentration level. Romo said that GreenVolts is at 1,300 times concentration, while Soitec is at about 500X, Amonix is at 600X, and SolFocus is in the 650X neighborhood. Amonix will be moving to 900X in their next-generation product. This means that GreenVolts' optical design and tracking has to be extremely robust and accurate -- and that could result in an improvement in efficiency and energy harvest. High concentration can have its drawbacks as well, with heat and hotspots playing havoc with chip performance and longevity.

Romo asserts that the tracker architecture is different than any other two-axis trackers and that the inverter is designed to work with the motion controller: it's not a multipurpose inverter but a specific device made just for CPV.

Like most CPV system vendors, GreenVolts will buy the III-V multi-junction solar cell from existing cell vendors such as Spectrolab, Emcore, Azure Space or newcomers Solar Junction, Semprius, JDSU, and Cyrium. 

ABB will sell the system for GreenVolts, providing a turnkey CPV system to its customers. ABB will essentially serve as the sales force and turnkey EPC for the startup. 

OK. Sounds good. So how much does it cost?

If you're competing head-to-head with PV panels at $1.00 per watt or solar farms with an all-in cost of $3.50 $2.50 per watt, GreenVolts should be able to furnish a dollar per watt or LCOE number that shows why they can win business against flat-panel PV. That's where Romo was less than completely communicative with this reporter. He said that because they were a full systems company, the dollar-per-watt value was not comparable to the PV module dollar-per-watt price and that there was a "nomenclature" mismatch because of the apples-to-oranges nature of the comparison of a CPV system to a PV installation.

Romo noted that the fact that the firm is winning business against PV vendors underscores the value and advantages of its CPV approach and the potential for CPV to deliver more kilowatt-hours per kilowatt in some environments.

Still, in a 1.5-gigawatt U.S. PV market and an 18-gigawatt global solar market, scale is vital -- and GreenVolts has to prove it can scale, scrub out cost, and genuinely out-perform and out-compete against PV and its CPV brethren, even as solar pricing continues to drop. Having ABB as a partner will certainly help with sales and bankability. In addition to GreenVolts, ABB Technology Ventures has recently made investments in ECOtality (EV infrastructure), Trilliant (smart grid communications), Power Assure (data center efficiency), Pentalum (wind power site assessment), and Aquamarine (wave power). ABB has also made a number of smart grid and EV-related acquisitions.

Greentech Media Research has forecast that CPV installations will exceed one gigawatt per year by 2015. GTM Research has profiles of all of the relevant industry players and a thorough analysis of the sector here.