During Solarvalue’s annual general meeting, Dr. Christian Bornhauser (pictured), CTO of Solarvalue, announced that the company had created the first solar grade silicon-ingot, which weighed in at around 15kg during several repeated tests on different plants. He assured that the purity levels of phosphorus and boron were less than 1ppmw and within the demanded specifications.
The company detailed that the key feature in the fundamental process is a multistage treatment for the separate reduction of phosphor, boron and other metals, which achieves the required purity levels. Simultaneously, the feed stock is permitted to differ on a larger scale making the whole process flexible when it comes to the quality of the metallurgical grade silicon.
Dr. Bornhauser stated, “We have already achieved far better results with the new process within the last couple of months than with the previous process, which was developed and tested for nearly two years in the US. We definitely have achieved a breakthrough in this area. We have produced the first ingot in a quality that seems to be adequate for manufacturing solar cells. Of course this has to be verified by means of further tests. The next step is going to be converting the material into cells by our partners. Altogether, this positively attunes us for the further development of the Solarvalue. It is still our goal to
produce solar grade silicon at compatible costs out of metallurgical grade silicon with the new production process. From today’s perspective, thanks to our rigid savings program the current liquidity is sufficient to build a larger pilot plant for ingots up to 60 kilograms each. But we will have to overcome a number of technical and especially financial barriers before we can produce in an industrial scale.”