ClearSign Technologies Corp., a leader in advanced combustion and sensing technologies that help industrial operators dramatically reduce emissions, increase efficiency and safety, and support the use of cleaner fuels including hydrogen, announces that, in conjunction with the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL), under its Small Business Innovation Research (SBIR) program, it has successfully completed the testing of its ClearSign Core™ Flexible Fuel, 100% Hydrogen Capable process burner branded as ClearSign Core 2.

“We are very pleased to publicly report the success of this flexible fuel burner development project,” said Jim Deller, Ph.D., Chief Executive Officer of ClearSign. “We are thankful for the SBIR program funding that allowed us to develop and demonstrate a technology designed to meet the real-world needs of U.S. refineries and chemical processing facilities. This technology enables compliant and cost-effective use of fuels ranging from 100% hydrogen, the full gamut of petrochemical and refinery hydrocarbon fuel gas blends, and natural gas in industrial heating operations. We believe that these ultra-low NOx results and ease of use are unmatched by any other burner that we know of in the market.”

Many industrial operators in these industries currently have access to a variety of opportunity fuels or specific gas compositions that traditionally require extremely costly heater modifications to meet regulatory nitrogen oxide (NOx) emission limits in place to help protect air quality and respiratory health.

ClearSign’s “Flexible Fuel Ultra-Low NOx Process Burner” project, which is nearing its scheduled completion and marking a significant 2.5-year effort, resolves this issue by facilitating fuel flexibility without compromising emissions compliance with the simple replacement of burner technology. This innovative technology allows industrial facilities to enhance operational flexibility, reduce costs associated with fuel procurement and regulatory emissions compliance, and reduce disruptions to operations — all of which may provide Americans with more affordable energy.

The ClearSign Core burner, scaled to 8 million British thermal units per hour, has demonstrated consistent performance across a range of fuel compositions, including 100% hydrogen, natural gas and various intermediate blends. This technology has also achieved NOx emissions that are consistently below 5 parts per million (ppm) across this entire range of fuel gas blends. This is accomplished through integrated features such as internally induced flue gas recirculation, fuel-lean premixing and a patented distal flameholder, all contained within a compact burner head designed for easy retrofitting into existing heater infrastructure.

“NETL’s investment in ClearSign’s technology is opening up significant operational advantages for the industry,” said Drew O’Connell, NETL federal project manager. “This solution allows companies to effectively utilize a broader spectrum of available fuels, ensuring they operate within permitted NOx limits without needing additional post-combustion controls like selective catalytic reduction or diluents.”

This project, which was made possible through a $1.65 million SBIR Phase II award from the DOE, is now progressing to the next stage to implement commercial field installations at operational industrial sites.

ClearSign expects that this advancement will significantly improve operational resilience and competitiveness within the domestic refining and chemical production sectors, aligning with NETL’s commitment to providing technological solutions for U.S. industrial needs, increasing industry partnerships and advancing hydrocarbon technologies.

This initiative underscores the impact of DOE’s SBIR program, which NETL helps administer, by empowering small businesses, such as Tulsa-based ClearSign, to develop technologies that are expected to address national industrial challenges and strengthen U.S. manufacturing innovation.

NETL is a DOE national laboratory dedicated to innovating and accelerating the nation’s energy solutions in hydrocarbon, geothermal energy and critical minerals production. With research sites in Albany, Oregon; Morgantown, West Virginia; and Pittsburgh, Pennsylvania, NETL operates as one laboratory to create advanced energy technologies that support DOE’s mission and enable affordable, reliable and secure energy to fuel human prosperity.