RENOVAL: solar concentration for aluminum recycling

Reducing greenhouse gas emissions and contributing to the circular economy are the main objectives of this initiative developed by Fraunhofer Chile and funded by Corfo through the Crea y Valida program.

The primary aluminum production industry generates 1.1 billion tons of greenhouse gases annually, accounting for 2% of global emissions. Conventional recycling reduces the energy required for the process by 95%, and therefore its emissions. However, it is not free of emissions, releasing half a ton of CO₂ into the environment for every ton of recycled aluminum.

The smelting process requires the highest energy consumption, which inspired the RENOVAL project: a solar aluminum recycling furnace developed by research engineers at Fraunhofer Chile.

By concentrating solar radiation directly onto a furnace located at the focal point, common aluminum waste—such as beverage cans, window frames, and engine pistons—can be melted without any need for other energy sources like fossil fuels.

After several months of work, and through various stages of R&D, the challenges related to design, manufacturing, assembly, testing, and commissioning of the prototype have been overcome, successfully achieving aluminum melting using solar energy.

The ultimate goal is to scale up the prototype with a fully constructed unit capable of melting diverse aluminum alloys at different capacities. The greater ambition: to eliminate the dependence on fossil fuels in metal smelting processes and to contribute to the circular economy through sustainability and renewable energy.

The project is funded by Corfo through the Crea y Valida program.

"Validating smelting without fossil fuels was a demanding challenge"

Designing, manufacturing, and commissioning a solar concentration system for aluminum smelting meant overcoming engineering and execution barriers. We faced issues in optics, heat transfer, and material resistance, constantly iterating until achieving aluminum smelting.

The manufacturing and assembly of the system were key to ensuring the correct focusing of solar radiation. Experimentally validating smelting without fossil fuels was a demanding challenge, but we managed to demonstrate its feasibility using solar thermal energy.

Today, RENOVAL is an operational prototype—a concrete step toward the decarbonization of recycling and high-temperature processes, demonstrating how Chilean engineering can deliver innovative solutions for a more sustainable economy. Working on RENOVAL has been both a technical challenge and an enriching experience.