The biggest roadblock for the commercialization of solar power in the United States is not the technology of the modules but the mundane back-end issues of permitting, installation, electrical controls and business practices, according to a report by the Rocky Mountain Institute.

The report, summarizing the institute's design charrette in June, concludes that "balance of system" (BoS) costs -- everything other than the modules themselves -- could be cut in half through streamlined, standardized approaches.

"Although solar PV has reached grid parity in select markets, significant reductions are still required to make it a true 'game-changer.' Technology development and economies of scale have helped manufacturers of both crystalline silicon and thin film PV modules create aggressive yet credible cost-reduction roadmaps," the report says.

That makes BoS costs -- representing about half of typical commercial and utility project costs -- critical to overall cost reduction for solar, the report says.

Cutting the costs of solar, including modules and supporting systems, by half from $3.50 or more per watt currently would establish solar as a viable option without subsidies, experts agree. "As $1 per watt everything becomes possible," said Energy Secretary Stephen Chu.

The institute's study concludes that back-end costs, now averaging $1.60 to $1.85 per watt, could be reduced to 60 to 90 cents. (The lower price is for ground-mounted systems; the higher, for units on rooftops.) Such a cost cut would offer "a pathway to bring photovoltaic electricity into the conventional electricity price range," the report concludes.

Increased solar installations, notably in California, have already helped reduce BoS expenses and total costs, said Thomas Rooney, president and CEO of SPG Solar, the second-largest solar installer in California.

No need for a technological 'miracle'
"Scale matters in this industry," Rooney said in an interview. A 1-megawatt solar project would have cost $8 million and taken six months to install two or three years ago, he said, requiring 14,000 worker-hours. Today, it can be done for $5 million, in six months, with 4,000 hours on the job, he added.

But cost reduction opportunities are fragmented and usually not coordinated, so gains are less likely to occur than with modules, the report authors said. At the most basic level, developers face community-by-community differences in structural and electrical codes. Coordinating the work of developers, installers, suppliers, regulators, utilities, and building owners with customers' demands is the challenge.

Robin Schaffer, senior vice president of sales and marketing for SunLink Corp., which has installed more than 150 megawatts of mounting systems, said his company is working on pre-assembly steps for systems to reduce costs. "We don't need technology breakthroughs," Schaffer said, speaking on a telephone conference call this week. "We just need the effort and cooperation among industry participants to get there, and we're getting that."

There are no "silver bullet" solutions, the report says. Solar power systems must be individually designed for unique site conditions around the country. But given that, more standardized models are needed that can then be adapted to local needs. "To achieve economies of scale, mass customization will be required whereby common parts and approaches can be readily customized for different locations," the report says.

Opportunities include better module and array designs to withstand high winds; standardized permitting; streamlined manufacturing; more "tool-less" installation automation to limit on-site labor, and improved direct-to-alternating-current conversion instruments. "Ultimately, plug-and-play installation approaches that don't require specialized labor may be possible," the report says.

Stephen Doig, program director at the Rocky Mountain Institute, said in the phone conference that the solar pilot projects around the country funded by the Energy Department provide the laboratories for attacking the cost and systems issues.

There is "one clear message," he said. Getting to good economies of scale does not require a major technology breakthrough. The component pieces are there. "We need to drive out the waste in the system. ... This is a matter of hard work now, not some miracle breakthrough."
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500