Silevo’s press materials describe its proprietary technology as hybrid because it uses elements of standard crystalline silicon solar cells and elements of thin film solar cells.
“It’s not a pure-play thin film play. It’s not a pure-play crystalline play. It’s a hybrid,” said Silevo VP of Business Development and Marketing Chris Beitel.
It “evolves silicon-based PV,” a press release detailed, “as the first hybrid solar solution to combine high-performance crystalline silicon N-type substrates, thin-film passivation layers and a unique tunneling oxide layer -- all in a single solar module.”
The oxide film layer is a new way in which Silevo’s cells release electrons when hit by sunlight and prevent the electrons from returning to their previously stable position (passivation counteracting recombination), Beitel explained. The thin film layer (doped amorphous silicon) emits the electrons, Beitel said. It is a proven emitter commonly used in LCD flat screens.
“We’ve used new materials to form that emitter,” Beitel said. “To our knowledge, no one has ever taken an n-type substrate, a semiconductor oxide and a doped amorphous thin-film layer and put them in a hybrid package.”
That conversion efficiency, Beitel said, has been verified by Sandia National Laboratories. It will be the basis of panels with “a better than 18 percent efficiency” which the company’s new 32-megawatt capacity production facility will turn out at a cost of "98 cents per watt."
The 21 percent cell efficiency, Beitel said, would rank Silevo’s cell with the few “high efficiency” cell makers such as SunPower (Nasdaq:SPWR), Sanyo, or Suniva. The 18 percent panel efficiency would rank Silevo ahead of First Solar’s (Nasdaq:FSLR) 12 percent and Suntech, Trina and Yingli “with modules efficiencies between 14.5 percent and 16 percent.”
Beitel said the hybrid concept’s use of oxide as the crucial middle layer evolved from experimental work with metal insulated semiconductor (MIS) cells carried out by solar energy pioneer Martin Green in Australia in the late 1970s.
Both Silevo’s smaller, lighter-weight, 235 watt-peak panels of 72 cells designed for rooftops, and its 305 watt-peak, 96-cell panels designed for utility-scale projects, have obtained Underwriter Laboratory (UL) and International Electrotechnical Commission (IEC) certification.
Silevo has taken the journey from R&D to production in a much shorter timeframe than other high efficiency panel producers, Beitel said. “SunPower, the industry leader in efficiency,” he said, “researched their integrated back contact [design] for about twenty years.”
The technology promises unprecedentedly high performance at low cost, Beitel said. First Solar’s 72 cents per watt cost produces only 12 percent efficiency, and SunPower’s 20+ percent efficiency comes with a cost of around $1.40 per watt, according to Beitel.
“We believe this tunneling junction technology can reach a manufacturing cost of around 61 cents per watt.," said Beitel.
The higher efficiency, he added, can also drive balance-of-system (BOS) costs lower by reducing the need for hardware and installation expenditures.
“If I am 42 cents per watt better in cost structure than SunPower, but have a performance that’s similar,” Beitel said, “I can reduce my pricing while scaling my operations to drive a system cost reduction.”
He acknowledged that Silevo’s business-world record is starkly different than that of industry veteran SunPower. But, he said, his claims are based on real-world performance. “We have been shipping sample product to our early customers for the past nine months. Panels have been installed on rooftops. Panels have been sent to third parties for validation. We have a performance lab on our roof in Fremont, CA. So we have real-world data. But in [terms of] megawatts, it is very small.”
CEO Zheng Xu and colleagues from Applied Materials founded Silevo in 2007. It emerged from “stealth mode” in October 2011 with two rounds of funding amounting to $75 million. The firm has a $33 million, 32-megawatt production facility coming on-line.