## Turning Coal Waste into Concrete’s Climate Solution: PHNX Materials Raises $2.5M Seed
Coal-fired power plants, long criticized for their environmental impact, may inadvertently hold a key to a greener future for the construction industry. PHNX Materials, a startup focused on decarbonizing concrete, has discovered a method to utilize coal waste, specifically fly ash, to significantly reduce concrete’s carbon footprint. The company recently announced a $2.5 million seed round led by Divergent Capital, KdT Ventures, and Overture, with participation from Jane Woodward.
Krish Mehta, co-founder and CEO of PHNX Materials, explained to TechCrunch that fly ash can replace up to 30% of cement in concrete. This substitution is crucial, as cement production is a significant contributor to global CO2 emissions. The EPA estimates that one ton of cement production in the U.S. releases roughly 0.8 tons of carbon dioxide.
The innovative approach of PHNX Materials lies in its ability to prepare the fly ash for use in concrete. The company has developed a process to strip the fly ash of undesirable impurities like sulfur and carbon. This purification process not only makes the ash suitable for concrete companies but also creates a new source of sulfur and aluminum, valuable compounds with applications in industries like fertilizer production.
Using ash in concrete isn’t a new concept. Ancient Romans used volcanic ash in their construction, and in modern times, transportation departments have utilized fly ash from coal plants. Caltrans, for example, mandates a minimum of 25% fly ash in concrete used for its projects. Jorge Osio-Norgaard, PHNX Materials co-founder and CTO, highlights that fly ash stabilizes concrete mixes, preventing chemical reactions that can lead to cracking and extending the lifespan of infrastructure projects like highways and bridges.
However, the decline of coal-fired power plants in the U.S., which now provide only 15% of the country’s electricity compared to 51% in the past, has led to a shortage of readily available, high-quality fly ash. This scarcity has driven prices up and forced concrete companies to reduce the amount of fly ash in their mixes, often replacing it with more carbon-intensive cement.
“We felt that unlocking a new supply of ash was the most scalable and quickest way to decarbonize the sector,” Mehta said. PHNX Materials aims to address this shortage by harvesting fly ash directly from landfills, processing it to remove impurities and extract valuable materials, and then selling the refined ash to concrete manufacturers. The company is also exploring the extraction of rare earth elements from the ash, further enhancing the value proposition of this waste product.
By tackling the impurities present in the majority of the 843 fly ash landfills across the U.S., PHNX Materials believes it can provide a sustainable and cost-effective lower-carbon alternative for the concrete industry. The company’s approach transforms a problematic waste stream into a valuable resource, contributing to both environmental sustainability and economic opportunity. The newly acquired seed funding will enable PHNX Materials to scale its operations and further develop its technology, bringing cleaner concrete closer to reality.