Recycled glass from panels verified suitable new high-grade PV glass ‘for the first time’

“We consider this a significant new step in our mission to make a circular economy for solar panels,” says Suvi Sharma CEO at the Texas-based firm Solarcycle. “We believe we are the first company to do this.”

“There’s over 50GW of solar manufacturing being built in this country and there’s zero gigawatts of solar glass being made here.”

Sharma’s comments come shortly after his company announced plans to build a “first-of-its-kind” solar glass recycling facility in Cedartown, Polk county, Georgia, where cullet is mixed with virgin materials to make these new glass sheets domestically with up to 50% recycled content.

“Our goal would be to eventually do it with 100%, but that starts getting harder,” says Jesse Simons, CCO at Solarcycle – adding that a great deal of innovation and a number of different technologies were needed to make 50% possible.

Referring to the major glass company’s verification of the technology, Simons adds: “This has never been proven before to our knowledge and it is a major breakthrough that validates our vision for the Cedartown factory.”

Glass transparency

At its other recycling facilities, Solarcycle’s processing usually involves cleanly taking the glass off used solar panels, then supplying it to a partner who refines the cullet further into fiberglass, says Simons. This product is then sold to US insulation and roofing company Owens Corning for its own fiberglass production.

While it is valuable to revert the used material towards making a key material for US infrastructure, not all glass is made equal. A large proportion of glass has a high iron content, which makes it less transparent and therefore less effective for solar applications. The iron can dilute sunlight hitting a panel and lower the conversion of the sun’s energy into electrons.

“The problem is we’re taking some of the most valuable glass on the planet, super low iron glass that is transparent for solar and has all these special benefits, and now we’re grinding it down to making fiberglass,” says Simons.

Furthermore, new solar glass and modules require sourcing virgin material from all over the world, and fiberglass can already be made with the lower-quality glass of old bottles and windshields.

It was this transparency and quality issue that led to Solarcycle’s idea of creating the new glass recycling factory specifically to create new solar sheets with all the benefits of manufacturing domestically in America.

Just a small fraction of the US$344m invested in the project will go towards a PV module recycling facility, which will have much the same functions as Solarcycle’s other facilities in Odessa, Texas and Arizona. The majority of the investment, instead, will go towards the ground-breaking glass factory.

“This whole thing is 1.5 million square feet, so it’s very large and the recycling piece is relatively small compared to the glass,” adds Simons. “The glass component of a PV panel accounts for more than 70% of its weight.”

The facility will produce 5-6GW of solar glass annually for sale back to domestic solar manufacturers as part of the United States’ effort to onshore PV manufacturing as much as possible to reduce reliance on imports. The glass sheets are applicable to all crystalline solar technologies, whether polysilicon, monocrystalline silicon, mono-facial or bifacial, but they are not suitable for thin-film cadmium telluride panels, which use a different type of glass.

“It’s sort of like blood type,” adds Simons. “We can take First Solar glass and turn it into crystalline glass, but you can’t take crystalline glass and turn it back into First Solar glass.”

Since Sharma and Simons outlined their company’s ability to recycle at least 95% of the value of a PV panel last summer, Solarcycle has obtained two more patents on top of the seven it had already filed, as well as receiving a grant from the Department of Energy (DoE) to progress its technology.

Growing interest from big names

Last summer, Solarcycle had already signed long-term partnerships with around 20 of the top 100 solar companies active in the US to reuse and recycle their solar panels, but demand has soared since then, and it now has more than 40 of the largest companies onboard, including nine big names that have announced their partnerships publicly. So far these include:

• Qcells North America
• EDP Renewables
• EDF Renewables North America
• Greenbacker Renewable Energy Company
• Orsted
• AES
• Silicon Ranch Corporation 
• Sunrun 
• Silfab Solar

“What’s really cool is it represents the whole ecosystem of the solar industry,” says Simons. “We’ve got manufacturers, the big developers, residential companies, distributors, EPCs. All of the biggest of those verticals have signed up to work with us, and it’s important, because to close the loop on the solar circular economy, you really do need to be working across that value chain.”

Earlier this month, the announcement that Korean-owned solar manufacturer Qcells had signed an agreement with Solarcycle to recycle its decommissioned modules in the US was also a significant “first-of-its-kind” partnership with a manufacturer, adds Simons.

Solarcycle has already found off-takers for more than half of the planned glass capacity, citing two main reasons. First, having a domestic supplier makes working together easier, reduces supply chain risk and disruption concerns, and allows for customers to easily visit Solarcycle’s R&D facilities to assess their own requirements for glass processing.

“The other big one is the climate benefits of using domestically produced recycled glass are quite significant and the big buyers of solar panels now – the Microsofts, the Apples, the Amazons, and the big utilities – they’re all really looking at what are the Scope 3 emissions profiles of the panels on buying,” says Simons.

For example, using 30% recycled glass content in new glass sheets reduces emissions by 30%, he claims, while manufacturing domestically without overseas shipping reduces carbon emissions by 66% on transportation.

“There’s over 50GW of solar manufacturing being built in this country and there’s zero gigawatts of solar glass being made here,” says Simons. “So, our ability to provide a premium product that also has all these sustainability benefits is something that we’re finding the big manufacturers really want to do.”

“The same thing is true for aluminium frames. While we’re starting with glass, our vision is to domesticate the supply chain. The two materials that make up the vast majority of the weight of solar panels are glass and aluminium and yet, all these manufacturers are building new panels with imported glass and imported aluminium.”

Last November, Solarcycle’s CTO and co-founder Dr. Pablo Dias co-released a study on how to reduce carbon emission intensity from manufacturing solar panels by as much as 85% through circular practices. These included, for example, decarbonising the solar supply chain, reusing and optimising materials such as aluminium and concrete, and powering operations with clean energy technology.

“That’s why we’re going to be powering our facility with solar as a way of further reducing the emissions,” adds Simons.

Repowering

There is a growing awareness that the economic end-of-life of a solar project may take place well before its technical end-of-life, says Simons. This happens when the economics of a PV system installed just 12-13 years ago already become questionable. Even if still functioning well, used panels can be replaced with new modules that could generate power with two to three times more efficiency, which is known as repowering. Furthermore, inverters, which are designed to last 10-12 years, may also need replacing, and for rooftops, there may be re-roofing requirements, so companies may look at the whole project and consider furnishing it with new technology.

PV Tech Premium recently discussed concerns that in the rush to install solar PV globally, the financial and environmental costs of decommissioning at end-of-life are being overlooked. While this issue would be assuaged somewhat if repowering became the norm, the ability to recycle PV modules efficiently remains critical given the great mass of PV equipment being installed.

Many landfills refuse to take solar panels, so they need to be shipped to a specialised facility instead. Thus, when shipping costs are included, Solarcycle estimates the cost of landfilling a module at between US$8-12, whereas the costs of recycling a PV panel comes out at US$15-20. Simons says companies are willing to pay this slightly higher cost for ethical reasons and most companies involved recognise the need to make solar panels as sustainable as possible.

“We’re constantly competing against landfills and we’re winning,” he adds. “And part of it’s because we’re doing the right thing.”