On Tuesday, Natcore announced it had successfully eliminated silver from an all-back-contact silicon heterojunction cell, and replaced it with aluminum. No loss of performance was said to have been recorded, and "substantial" cost savings made possible.
When asked how far away Natcore is from commercializing the solar cells, David Levy, Director of Research & Technology at the companys R&D Center in Rochester, tells pv magazine that high efficiency laboratory demonstrations will be held in the next two to three months. "We expect pilot demonstration in early 2016, and if successful production availability at some time in 2016," he adds.
Regarding efficiencies of the cells, Levy explains, "All of the work to date has focused on the new metallization approach, and has been done with cells that are not optimized for their structure or optical properties.
"As a result, the relevant metric at this point is the effect on efficiency of moving from silver to aluminum, which is negligible our main focus at this point is applying these approaches to high quality optimized substrate so that we can report hard and relevant efficiency numbers. We are on an aggressive timeline regarding that, and expect to be at that stage in the next 2 to 3 months."
Levy says that while concrete details cannot currently be disclosed, production equipment will not need to be significantly altered. "The metallization processes we are developing will replace current metallization operations, but otherwise have low impact on a given cell line," he says.
Natcore is still working on detailed cost models of producing solar cells with aluminum instead of silver, Levy says, adding that the main driver is the significant cost difference between silver and aluminum.
Although it boasts high conductivity, silver is very expensive. And, while twice as much aluminum is needed as silver, "raw material costs would still be just 0.6% of the direct material cost of using silver in the cell," said Natcore in a statement detailing the initial announcement.
Currently, silver costs around US$15.28 per troy ounce contributing to roughly 30% of a silicon cells production cost whereas the same quantity of aluminum is said to cost $0.05.
Four companies two in the U.S., one in Australia and one in China are said to have expressed interest in Natcores new cell. "These are all companies that are planning to get into solar energy. They want to build cell fabs, module fabs, and/or power plants," says Levy.
President and CEO, Charles Provini added, "We will be filing the necessary patents on several of these applications early next week. Once they are filed we would anticipate approaching other manufacturers and equipment suppliers more aggressively. We have been somewhat quiet about our success until we protected our IP … Once the patents are filed, we will be able to say much more about the new cell and how we got there."
Update: This article was modified on August 24 to include commentary by Charles Provini, and to change the number of interested parties from three to four.