Using feedback from NREL and the CIGS module manufacturers, Funkenbusch expects the redesign to have increased light transmission, better durability and lower cost. "We want to make sure we
have a product that lasts 25 years," he says. "That's where SunShot helps us out."
The new manufacturing line will be at an existing 3M factory in Columbus, Missouri. According to the Columbus Daily Tribune, the line will add 120 solar jobs to a plant that's shed jobs for years.
Construction of the line is underway and production Construction of the line is underway and production is set to begin in early 2012. There are indications that CIGS module manufacturer
SoloPower, which recently secured a $197 million DOE loan guarantee for a new factory in Wilsonville, Oregon, will be the first customer.
Varian Semiconductor
Target: IBC Cell Production, Cost
Recent NREL tests have measured SunPower's interdigitated-back-contact solar (IBC) cells at the highest conversion efficiencies to date. The only factor preventing SunPower's technology from becoming the industry standard is cost.
The principle is very simple: IBC cells eliminate frontside metallic conductors, which typically cover 5-8% of the physical surface of a wafer. Move the wiring to the backside, more sunlight gets absorbed, and cell efficiency spikes.
"Currently, IBC solar has the highest efficiencies, but it's very expensive to make," says Jim Mullin, general manager for solar products at Varian Semiconductor. "In solar manufacturing, every step adds cost, adds complexity, and can result in potential yield loss." In Gloucester, Mass., Varian is using $4.8 million in SunShot funding to develop an ion-implant tool that promises to slash the number of manufacturing steps from 21, necessary in the IBC process today, to eight.
Ion implantation is far from a novel concept - implanters are integral to semiconductor device fabrication and have long been used to make computer chips. Varian's been selling the tools to the electronics industry since 1975 and has an ion implanter, the Varion Solion, for conventional PV cells that's already running in high-volume production. SunShot backing will be used to redesign the Solion so that it can to do backside wafer patterning necessary for IBC cell production.
"We're the first ones to do this," Mullin says. "We are in a unique position because we're the only ones that can do it without impacting the tool's productivity - because we own the intellectual property."
Mullin says that Varian has matched its DOE funding with internal investments well north of $20 million. He expects the tool to be commercially ready within three years.
It's unclear how much the reduction in production complexity will reduce IBC costs, however. Module manufacturers have some ground to make up before IBC solar is cost-competitive with other PV technologies.
SunPower is the only company commercially producing IBC modules today and is operating at a production cost of around $1.70 per watt, while Chinese crystalline-silicon manufacturers are producing at about $1.20 per watt, and First Solar, a CdTe thin-film manufacturer, is now down below the $0.75 mark.
NREL Incubator Program
Not all SunShot funding is going toward projects at 1366 Technologies, 3M, PPG, Varian Semiconductor and Veeco, a fifth recipient. Another $7 million is being injected into the National Renewable Energy Lab's Photovoltaic (PV) Technology Incubator program.
Started in 2009, the incubator program is primarily tasked with hastening nascent PV technologies' transition from the drawing board into the lab. There are two funding tiers: The first supports development of commercially viable prototypes; the second helps companies scale up to the pilot-project manufacturing stage.
SunShot funding targets four companies:
Tier One
Caelux (Pasadena, CA) - $1 million: developing a flexible PV-manufacturing process that minimizes the amount of semiconducting material used.
Solexant (San Jose, CA) - $1 million: developing a new printable nanoparticle thin-film ink from common nontoxic substances.
Stion (San Jose, CA) - $1 million: developing a technology consisting of two stacked high-efficiency thin-film devices, offering improved absorption of light.
Tier Two
Crystal Solar (Santa Clara, CA) - $4 million: commercializing single-crystal silicon wafers, four times thinner than standard cells.
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This article first appeared in Solar Today, a SustainableBusiness.com Content Partner. Read the digital edition of the full magazine.
