Fresh funds to scale solar energy for cement production

Clinker is produced by fusing limestone, clay, and other materials in a rotary kiln at temperatures nearing 1’500°C. Fossil fuels are typically used to heat the kiln and are responsible for approximately 40% of the direct CO2 emissions of the process. Replacing fossil fuels entirely with solar energy will be a game-changer in the industry’s efforts to achieve carbon neutrality.

Synhelion, a global pioneer in the field of carbon-neutral solar fuels, developed a breakthrough technology that delivers high-temperature process heat beyond 1’500°C. This makes it possible to drive industrial processes such as fuel production and cement manufacturing with solar heat for the first time. The technology will be used to produce clinker without using fossil fuels.  Synhelion is currently building its first industrial solar fuel plant in Germany. The first commercial production facility is planned for commissioning in Spain by 2025.

The startup has joined forces with CEMEX and Sandia Laboratories to implement the Solar SMEAD project, funded by the U.S. Department of Energy. The project will investigate methods to reduce carbon dioxide emissions, lower process temperatures, and increase the efficiency of clinker formation using solar energy. The team will assess the conditions to maximize heat transfer to the raw cement mix.

CEMEX and Synhelion have been collaborating to introduce concentrated solar thermal (CST) in the cement production process, achieving the first successful laboratory-scale demonstrative pilot in 2022 by producing the first-ever solar clinker. In the joint project, Sandia Laboratories will contribute unique research facilities as part of the National Solar Thermal Test Facility and subject matter expertise to help accelerate the adaptation of the technology to cement manufacturing.

“Few renewable technologies are capable of generating heat at the temperatures needed to process raw cement feedstock,” said Nathan Schroeder, Sandia researcher and principal investigator for the Solar MEAD project. “This project will advance our understanding of how to use concentrating solar technology to gather and deliver the heat to existing cement production facilities and will have crosscutting relevance to other ore processing industries such as refractory, ceramics, and battery production.”

Successful adoption of this technology in cement manufacturing will allow for 100% replacement of fossil fuels and result in a more efficient and lower-cost carbon capture process compared to the current state-of-the-art technologies.

(Press release/RAN)