Solar power used to produce clinker for the first time

1 min read

Solar-driven cement plants have moved forward with the production of the world’s first solar clinker, the key component of cement, by CEMEX and Synhelion.

The pilot plant installed at the Very High Concentration Solar Tower of IMDEA Energy, Spain (Image: Synhelion)

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 they are responsible for approximately 40 per cent of direct CO2 emissions of the process.

“The production of the first solar clinker is an exciting milestone for this transformational technology. It is proof of our commitment to deliver tangible outcomes through innovation to achieve our goal of delivering only net-zero CO2 concrete by 2050,” said Fernando A. Gonzalez, CEO of San Pedrom, Mexico-based CEMEX.


The Synhelion and CEMEX research and development teams set up a pilot batch production unit to produce clinker from concentrated solar radiation by connecting the clinker production process with the Synhelion solar receiver.

The pilot was installed at the Very High Concentration Solar Tower of IMDEA Energy, located in Spain. Synhelion’s solar receiver delivers temperatures reaching over 1,500°C by heating a gaseous heat transfer fluid to provide the necessary process heat for clinker production.

“Our technology converts concentrated sunlight into the hottest existing solar process heat – beyond 1,500°C – on the market,” said Dr. Gianluca Ambrosetti, CEO and Co-Founder of Synhelion, which is headquartered in Switzerland. “We are proud to demonstrate together with CEMEX one specific industrially relevant application of our fully renewable, high-temperature solar heat.”

The pilot is the first successful calcination clinkerisation ever achieved using only solar energy. The clinker was used to produce cement and was then further processed to produce concrete. In the next phase of their joint research and development project, CEMEX and Synhelion aim to produce solar clinker in larger quantities as they work towards an industrial scale pilot at a cement plant.