First Solar executive sings praises of 'infinitely scaleable' community PV

First Solar believes the potential for community solar to be "much, much larger" than for residential rooftop, a director says, as the company plans its approach to the booming US distributed-generation market.

Compared to the "somewhat limited" market potential for rooftop solar, the largest US-based PV manufacturer views the emerging market for community projects as "infinitely scaleable", says Eran Mahrer, its senior director for utilities.

First Solar, the biggest Western solar manufacturer, and among the world's largest developers of utility-scale projects, remains stuck on the sidelines of the fast-growing US rooftop sector.

While First Solar's cadmium telluride thin-film modules are extremely competitive in the utility-scale sector, where space is less of an issue, their lower conversion efficiency compared with the crystalline silicon modules made by rivals such as SunPower and Trina means they are uncompetitive in many rooftop settings, where space is often constrained.

Until recently,it appeared that First Solar's approach to the distributed-generation market would centre on TetraSun, the high-efficiency silicon solar start-up it acquired in April 2013. But in December, the Arizona-based company opened a second line of attack by taking an equity stake in Colorado's Clean Energy Collective (CEC), the leading player in the fast-growing but still-tiny community solar sector.

CEC does not build rooftop projects. Rather, it works with utilities to develop community solar "gardens" – typically ground-mounted projects running from several hundred kilowatts to a few megawatts.

The utility's customers are offered the opportunity to buy into the projects on a per-module basis. The customers then see their power bills lowered based on the amount of electricity their share of the project generates.

James Hughes, First Solar's chief executive, now sits on the board of CEC, which is involved in 60% of US community solar programmes. 

For now, the most obvious candidates for community projects are people without a house to put panels on, or whose poor credit score precludes them from obtaining a solar lease or power-purchase agreement, but who are nevertheless interested in the benefits of solar.

Over the long run, however, community and rooftop solar may be on a collision course. "It's possible that community solar draws on some of the same pool [of potential customers]," Mahrer acknowledged, taking questions at the Solar Power Generation conference in California.

In First Solar's opinion, community projects have many advantages compared to rooftop systems, including economies of scale and their ability to be sited in areas where they are most conducive to grid reliability. 

First Solar sees community solar as a compromise between consumers and utilities, with consumers still able to offset their power bills by investing in PV, but utilities dictating where the projects are built and ultimately maintaining control over them.

"Community solar allows this unique opportunity to take a resource, site it to the benefit of the utility, position it in a way that it can... create real benefit for individual customers, all in a universe where the utility continues to be the driver in deploying that resource," Mahrer says.

"If you do that, and you do it right, and you do it at scale, you can drive the cost of [solar energy] low enough that we believe over time that market is what we'll call infinitely scaleable."

Mahrer concedes that residential rooftops still represent a potentially "very, very large market" in the US. But he also calls that market "somewhat limited".

"The population of people who are owners of single-family homes, that have the right [rooftop] orientation and the right credit [score]... is a limited population."

"Community solar is not limited to that population. The universe opened up by community solar is much, much larger."