Interview: Terry Jester, Silicor Materials

Reg Tucker, US Editor, Renewable Energy Focus

Extolling the virtues of 'solar-grade' silicon alternatives

While attending SPI 2013 in Chicago this past fall, Renewable Energy Focus magazine had an opportunity to sit down with executives from Silicor Materials. These included: Theresa (“Terry”) Jester, CEO; John Beaver, chief financial officer; and Michael Russo, WW sales, marketing and business development. The Silicor Materials team discussed, among other topics, their technological capabilities, marketing approach, and current view of the PV silicon business. Following are excerpts from that discussion:

Q: Tell us about Silicor Materials and your technology.
Terry Jester: Silicor Materials manufactures high-quality solar silicon and aluminum master alloy. Leveraging a proprietary process, Silicor provides the lowest-cost alternative to the electronic-grade (EG) silicon commonly used throughout the photovoltaic (PV) industry. Silicor’s solar silicon delivers consistent quality and a more fit-for-purpose option for PV cells and modules than over-engineered EG silicon. The resulting solar cells achieve conversion efficiencies greater than 17 per cent — on par with EG silicon, but at roughly half the production cost. Our process also limits the environmental impact of purifying silicon by producing zero waste.

Our technology confers benefits throughout the solar value chain, enabling solar PV cell and module manufacturers to increase their margins in an increasingly competitive global market. Our process has been fully validated and, to date, we have produced more than 25 million cells and 700 MT of solar silicon, and more than 1,000 ingots have been cast with our solar silicon.
Q: What is solar silicon, and how does it differ from the silicon available to the solar industry today?
Jester: Since the 1960s, the standard method of polysilicon production has been the Siemens process, which yields EG silicon with a purity of 99.9999999 per cent. EG silicon is a vital feedstock for the semiconductor industry, where this level of purity is absolutely essential. However, the solar industry does not require this same level of purity, especially when it comes with the highest price tag in the supply chain. With this in mind, Silicor has designed a proprietary silicon manufacturing process that yields a solar-grade silicon to better meet the cost needs of the solar industry while still delivering a purity of 99.9999 per cent to 99.99999 per cent. Further, as mentioned previously, the production process is environmentally benign.
Q: How is Silicor Materials able to manufacture solar silicon so cost-effectively?
Jester: We’re able to achieve these production efficiencies by simplifying the silicon purification process. In comparison with the EG process, we reduce the number of phase changes necessary by half. The EG method requires four phase changes: solid to liquid; liquid to gas; gas to liquid; and, finally, liquid to solid. Our technology eliminates the gaseous phase and does not require treatment with tricholorosilane gas, which is toxic. The process only goes through two phases — solid to liquid and liquid to solid — yielding very pure silicon ready for application in the solar industry. By halving the number of steps necessary, our energy requirements are reduced by approximately 25 per cent, resulting in significant improvements in production cost. Overall, our commercial plants require two-thirds less capital than production plants using the EG process. Additionally, our process yields aluminum-silicon alloy and polyaluminum chloride (PAC) for use in the automotive and water treatment industries, respectively. 
Q: You mentioned earlier that solar silicon confers benefits throughout the solar value chain. Can you explain this in more detail?
Jester: A few years ago, a global PV module oversupply caused a rapid decrease in prices and led to the failure of non-competitive PV manufacturers. The manufacturers that now remain are still struggling to preserve their businesses in this crowded, commoditized market.

As manufacturers search for ways to boost their margins and stay competitive, they have to find ways to bring down cost. Increasingly, their focus is shifting to solar silicon, which (as mentioned previously) presents the single highest cost in the upstream supply chain. With recent reports predicting that global solar silicon prices will increase by 25 per cent in 2014, the need for an alternative has never been more apparent. 

Because we can produce solar silicon at approximately half the cash cost of EG silicon — just $9/kg — we open the door to considerable cost savings for module manufacturers, resulting in a more profitable and a healthier solar industry.
Q: Can module manufacturers easily integrate your solar silicon into their manufacturing processes?
Jester: Absolutely. Whether utilized as a drop-in replacement for EG silicon or as part of a blend, Silicor’s solar silicon can significantly improve the economics of solar cell and module manufacturing. Our product has been vetted and validated by almost 20 module manufacturers who have used our solar silicon to meet anywhere from 10 per cent to 100 per cent of their needs.
Q: In addition to cost and performance, are there any other advantages in Silicor’s manufacturing process?
Jester: Due to our environmentally friendly, closed-loop process, our manufacturing facilities can be placed in light industrial parks, or co-located with our cell manufacturing partners’ facilities. This differentiator reduces the time and financial resources required for delivery to the end user while allowing Silicor to easily scale its output to meet customer demand. We also reduce the capital requirements to build a plant by approximately two-thirds, reducing depreciation.
Q: What is Silicor Materials’ commercialisation strategy?
Jester: We have already proven the technology at commercial scale via our silicon purification operations in Ontario, Canada. We also have a state-of-the-art research and development center located in Berlin.

Our next phase of growth will come from a new solar silicon manufacturing plant capable of producing 16,000 metric tons per year. We are currently in advanced development work at three sites, and we are working with a top-tier investment bank to raise funds for the plant. We already have letters of intent in place to account for almost all the output from this new facility, meaning that our customer base is already in place.

With the key elements of a strong foundation in place — a commercially proven technology, a robust customer base and ripe market conditions — we expect 2014 to be an important year for Silicor and for the continued adoption of solar silicon. 
Theresa (Terry) Jester, a 30-year veteran of the solar industry, is the CEO of Silicor Materials. She has extensive experience in the manufacturing and engineering of photovoltaics and led efforts to ramp up manufacturing operations to full production for a variety of photovoltaic technologies, including silicon cell-based photovoltaics. Formerly Entrepreneur in Residence at Hudson Clean Energy, Ms. Jester has managed large solar operations and held engineering positions at SoloPower, SunPower, SolarWorld, Siemens, Arco and Shell. 

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Photovoltaics (PV)  •  Solar electricity