About seven years ago, Vince Allen broke into the garage he shared with some roommates in a Sydney suburb and set out to try to shake up the solar industry. At the time he was a PhD candidate at the University of New South Wales, and he had an idea to make solar panels much cheaper: replace the expensive silver normally used to extract electricity from devices with abundant and cheap copper.
Well-funded labs and giants had already struggled with this very attempt to get rid of silver. Allen was unfazed and built his own team to test idea after idea in one quick clip, until he found a technique that worked. SunDrive Solar, the company he co-founded in 2015 based on this research, proved this week that it has produced one of the most efficient solar cells of all time, according to a leading independent test lab. And SunDrive did it with copper as the metal in the core.
If SunDrive can mass-produce its technology, and that’s a big yes, the Australian startup could lower the cost of solar panels and make the industry much less dependent on silver. “The thing about copper is that it is very abundant and generally about 100 times cheaper than silver,” said Allen, now 32 years old.
SunDrive has raised about $ 7.5 million to date from Blackbird Ventures and other big name investors. Mike Cannon-Brookes, one of Australia’s richest people, has backed the startup through his Grok Ventures; So has former Suntech Power Holdings Co. chief Shi Zhengrong, sometimes called the “Sun King” for his outsized role in the solar panel industry. The company also received more than $ 2 million through a grant from the Australian Renewable Energy Agency, a government body tasked with pushing green technology.
About 95% of solar panels are built with photovoltaic cells made from silicon wafers. To draw electrical current from cells, it is usually necessary to fuse them with metal contacts. Silver has long been the metal of choice because it is easy to work with and very stable. Solar panel manufacturers rely on a screen-printing process similar to that used to place designs on T-shirts, pushing a thick silver paste through a mesh and over their silicon cells in a fixed pattern. If you’ve ever seen a solar cell up close, the faint, thin lines running through it are the metal electrodes.
Solar panel manufacturers now consume up to 20% of the world’s industrial silver each year. When silver prices are high, the metal alone can account for 15% of the price of a solar cell. Even after a big rally this year, copper is trading for just over $ 9,000 a ton in London. That same amount of silver would cost almost $ 770,000. The solar industry will need more and more silver as it continues to boom, and at some point SunDrive backers believe demand for the metal is likely to limit the spread of solar electricity needed to reduce greenhouse gas emissions. .
The problem preventing solar panel manufacturers from abandoning silver has been that copper does not lend itself to standard manufacturing techniques, in part because it does not adhere well to solar cells. Copper also oxidizes more easily, affecting its ability to conduct current.
The University of New South Wales has a long history of advancements in solar technology, and Allen focused on this copper conundrum as the heart of his graduate studies. However, instead of working in the labs at school, Allen thought that he could perform experiments more quickly by building an R&D setup in a garage. He spent a couple of years assembling machines that contained a mixture of liquid copper of his own creation that could deposit the suspension in a solar cell in a controlled manner.
“I always wanted to follow my own curiosity and try a lot of random and crazy ideas,” Allen said. “It required some discretion since there were neighbors, and I was walking around in a lab coat with all these chemicals.”
He took hundreds of experiments, but eventually developed technology that allows thin lines of copper to be safely attached to solar cells. He started SunDrive with his former roommate David Hu, 33, in an attempt to commercialize the technology. The company now has about a dozen employees. Hu, who grew up in China and moved to Australia at age 16, handles business affairs, while Allen sticks to science.
Just this week, SunDrive received the official news that it had set a record for efficiency in which its particular solar cell design converts light into electricity. The result came from analysis by the Hamelin Solar Energy Research Institute (ISFH), a German organization known for conducting such tests. The efficiency figure, 25.54%, will mean little to people outside of the solar industry. But it is one of the key metics by which cells are compared.
Large Chinese solar cell manufacturers have broken efficiency records for years. Longi Green Energy Technology Co., which sold $ 8.4 billion of solar technology last year and is one of the world’s largest manufacturers, maintained the previous top mark of 25.26%.
Startups in this part of the solar market are rare due to the daunting prospect of competing against giant companies that produce solar cells by the millions in large, expensive factories. Chinese companies dominate, with collective control of most of the global capacity for the supply chain. “The capital required to start a new company is huge, and even then it’s not a terribly profitable business,” said Zachary Holman, a professor who studies solar materials at Arizona State University. Still, he said, there are a handful of companies like SunDrive that are targeting technical advancements that could give them a shot. SunDrive “would need something new like that to be able to compete.”
The next step for SunDrive will be to demonstrate that it can mass produce solar cells reliably and economically. “What they have shown so far is high throughput in a cell,” Holman said. “They didn’t show 10,000 high-throughput cells coming out of a multi-hour build run.”
Allen and Hu said they have not yet decided on the exact path they will take in the future. They are likely trying to form a partnership with one or more of the big manufacturers rather than trying to build an entire solar panel business from scratch. “We could buy partially complete solar cells and then finish them with our copper process,” Hu said.
Shi, the SunDrive investor nicknamed “Sun King,” said it will be difficult to find enough affordable silver if the solar business grows as predicted. Over the next decade, he expects manufacturers to move to a 50-50 split between silver and copper in solar cells. “The switch to copper is something we have wanted for a long time, but it has been very difficult to do,” he said.
He recalled visiting Allen in his home laboratory and being amazed at what the PhD student had accomplished. “He had all these simple tools and things that he had bought from Amazon,” Shi said. “Innovation is really about the individual and sometimes timing, and not being in a large, resource-rich company.”
