Solarcycle is a California-based startup that provides comprehensive solar panel recycling services. The company has developed proprietary recycling technology for solar panels. Since its founding in 2022, Solarcycle has raised $37 million in funding and partnered with companies such as Sunrun to recycle solar panels. The company aims to build a circular economy for solar and renewables by maximizing solar sustainability.
Challenges: solar cell recycling
Photovoltaic modules are devices that can convert solar energy to electricity. Even though it is considered “green” equipment for producing alternative and renewable energy, it has a limited lifespan of 20 to 25 years and, at the end of its useful life, it becomes an electrical and electronic waste that needs special care. By 2030, the global accumulation of decommissioned solar panels could reach 8 million metric tons, and by 2050, 80 million metric tons.
Recycling solar panels is an important process that is still in its early stages. Today, only about 10% of panels are recycled in the United States.
Solar panels that end up in landfills may take hundreds of years to decompose, leading to waste buildup and taking up valuable landfill space. This waste can also release harmful chemicals and greenhouse gasses. Some solar panels contain toxic substances such as cadmium, lead, and mercury, which can leach into the soil and groundwater if not disposed of properly. This pollution can be harmful to wildlife and human health, as well as the food chain.
Solar panels contain valuable materials such as silicon, aluminum, copper, and silver, which are non-renewable resources. By 2050, the materials in decommissioned solar panels could be worth an estimated $2 billion. If these materials are not recycled, they will be lost forever, which will increase the demand for new raw materials and contribute to resource depletion.
However, recycling solar panels is a major challenge due to several factors.
One of the biggest challenges is the lack of harmonized regulations, waste management infrastructures, and coordination between the energy and waste sectors. The United States has no federal laws in place that mandate the recycling of solar panels, making it difficult to incentivize manufacturers and businesses to properly dispose of modules. However, some individual states have policies that classify panels as hazardous waste.
Another challenge is the cost of recycling solar panels, which currently far exceeds the cost of disposing of them in a landfill. Recycling a solar panel costs between $20 and $30, while dumping the same panel in a landfill costs between $1 and $2. To build a robust PV recycling network in the United States, it is essential to reduce the overall cost of recycling. Rising energy costs, improved recycling technology, and government regulations may pave the way for a solar panel recycling market.
Recycling is already established in the glass, metals, and electronics industries, which can accommodate solar panels and other components of solar power systems. These processes typically involve crushing, shredding, and milling, usually after removal of the frame and junction box. An ideal recycling system would recover as much material from solar panels as possible. However, some materials located within the solar cells may be more difficult to recycle, such as silver, internal copper, and toxic metals like lead and cadmium.
The solar cell recycling industry is new and still growing, with researchers examining how to commercialize recycling to economically recover most of the components of a solar panel.
Solarcycle’s recycling process is designed to maximize solar sustainability by providing a low-cost, eco-friendly, and comprehensive process for recycling and reusing retired solar panels. Solarcycle is already able to recycle 95% of the valuable components of solar panels, including aluminum, glass, copper, silver, and silicon. The company aims to establish a circular supply chain for the solar industry.
Solarcycle might use the solar cell recycling process developed by its CTO and Co-Founder, Dr. Pablo Dias. The recycling process is capable of separating and recovering the different macro components of crystalline silicon photovoltaic modules using mechanical operations and solvent immersion under conditions specific and a sealed apparatus. The completely separated and recovered macro components include metallic frame, intact (undamaged) glass, junction box, polymeric substrate, metallic contacts, and a mixture of materials, including the encapsulant, other metallic materials and the semiconductor.
Solar panel recycling technology
The first step of the recycling process is the removal of the outer aluminum frame and the junction box.
As shown in the diagram below, a solar cell panel has a frame and junction box. The frame is responsible for the physical stability of the structure. The junction box is responsible for the electrical connections of the photovoltaic module. The junction box and the metallic frame of the module are mechanically separated.
Once the aluminum frame and the junction box are removed, the whole solar cell modules are submerged in the organic solvent (toluene) in the apparatus as shown in the diagram below. The encapsulants of EVA are dissolved by toluene, allowing the separation of intact tempered glass and silicon solar cells.
The apparatus consists of a rigid metal container and an inert lid. The container must be thermally conductive at the bottom to allow heat conduction to heat solvent in the container. The inert material in the lid aids in sealing and thermal insulation. To increase the efficiency of the apparatus, the edges are sealed sealant and mechanical compression. A reflux system is placed in the center of the inert lid in order to ensure that the solvent is preserved.
The apparatus is heated between 70 and 100 ºC with a heating plate and left to rest for a period of between 24 and 68 hours.
At the end of the period, the apparatus is then opened, the solvent (liquid phase) and the module (solid phase) are recovered, which will be partially separated. Separation results in intact tempered glass, polymeric substrate, copper metallic contacts and mixture of encapsulant, silicon, silver, and aluminum.
The sealed system is manipulated at regular intervals in order to preserve the solvent and optimize process time.
The mixture of encapsulant, silicon, silver and aluminum can be further separated with a thermal process of pyrolysis in an inert atmosphere at 500 ºC in order to eliminate the encapsulant and remain with a fraction containing silicon, silver and aluminum.
The recycling process of Solarcycle has a high efficiency, being able to recover 100% of the glass, the metallic frame, the junction box, the metallic contacts, the semiconductor, the polymeric substrate, and other metals.
The quality of the recycled product is superior to that of other techniques because the components are intact (which are not broken or comminuted) and pure (because there is no use of high temperature, which causes impurity atoms to diffuse into materials of interest). Intact glass can be recovered, as can other materials (metallic contacts, frame, substrate). Furthermore, silver does not migrate into the silicon crystal lattice from the cell surface.
Another advantage of Solarcycle recycling process is the reduction in the amount of waste, effluents, and emissions generated, since the process uses a solvent that can be reused and reused several times and does not use acids or produce emissions typical of thermal separation techniques.
Finally, Solarcycle recycling process has a very low cost compared to conventional techniques which use thermal processes to achieve the separation.
Recycling solar panels can have significant economic benefits. Recent projections indicate that recyclable materials from solar panels will be worth more than $2.7 billion by 2030. The International Renewable Energy Agency (IRENA) estimates that the recycling industry of solar panels could be worth $15 billion by 2050.
Diverting solar panels from landfills to recycling saves space in landfills in addition to capturing the value of the raw materials. The cumulative value of recoverable raw materials from end-of-life panels globally will be about $450 million by 2030, which is equivalent to the cost of raw materials currently needed to produce about 60 million new panels.
Solarcycle raised $30 million in a recent Series A round, bringing the company’s fundraising total to $37 million since launching in 2022. The company aims to use the funds to scale its recycling capacity and expand materials remanufacturing. The company has partnered with Sunrun, a leading residential solar company, to launch its new technology-driven recycling platform.
Video: SOLARCYCLE’s State of the Art Recycling Facility in Odessa, Texas
Solarcycle is funded by 8 investors, including Closed Loop Partners, Urban Innovation Fund, Prologis Ventures, Fifth Wall, HG Ventures, Lyndon Rive, Tom Dinwoodie, Peter Rive. Prologis Ventures and Fifth Wall are the most recent investors.
Suvi Sharma is the CEO.
Solarcycle Board Member and Advisor
Danielle Joseph and Peter Rive are Board Member.