Basalt-based Portland – A new thermodynamics-based assessment finds making Portland cement from basalt could reduce CO2 emissions by almost 30% on a fossil-heavy power grid—and much more with clean electricity—if inefficient lab steps can be made scalable and paired with recovery of
On the face of it. cement is the kind of climate problem that seems designed to resist change: it’s everywhere. it’s hard to replace. and much of its carbon footprint comes from the way it’s chemically manufactured.. A new analysis is now asking whether a different rock—basalt—could turn that formula toward lower emissions.
The pathway the researchers modeled centers on converting basalt minerals into calcium oxide, the key chemical step behind Portland cement.. In theory, the chemistry is friendlier than the standard limestone route.. Thermodynamics suggests that turning basalt minerals into calcium oxide needs around half as much energy as converting limestone.
But the researchers also point to a stubborn reality—today’s methods for enabling that conversion are inefficient.. When all the extra steps are included. along with follow-up reactions needed to restore acid or other chemicals to a usable state. the overall energy requirement comes out to a little more than double that of traditional production from limestone.
Even with that penalty, the emissions math shifts. The analysis argues that direct liberation of CO2 from limestone would be eliminated. Instead, the process could run on electricity, changing what drives the carbon footprint from geology to power generation.
If electricity comes from a fossil-fuel-dominated grid, the researchers estimate emissions would be cut by almost 30 percent. With clean electricity, they say, most of the remaining emissions would disappear.
That is where the tension lives: the environmental payoff is meaningful, but the trade-off is cost. As the study notes, expense tends to decide which options actually scale, even when the climate case is strong.
The paper also highlights another potential pressure release—basalt doesn’t just provide the calcium needed for cement.. The other minerals it contains could be separated and recovered as valuable materials such as iron, magnesium, and aluminum.. And the leftover silicate material could serve as an additive for Portland cement instead of relying on something like coal ash.. The researchers stress that coordinating these outputs would be necessary for the whole approach to become more economically feasible.
The study. published in Communications Sustainability (2026). presents a relatively simple analysis—but it maps out what would have to change for basalt-based cement to move from lab concept to viable industrial practice.. Cement may still be one of the hardest greenhouse-gas sectors to crack. but the direction of travel is clear: reduce the carbon-intensive limestone step. electrify the process. and capture more value from the rock itself.
basalt cement Portland cement CO2 emissions greenhouse gas reduction thermodynamics decarbonization electricity grid iron magnesium aluminum recovery
So basically turn rocks into cement? Sounds fake but I’ll take it.
If it cuts emissions like 30%, why aren’t they doing it already? I saw another post saying cement is basically unavoidable, so this feels like good news. Also the grid thing confuses me… like does it only work if we have no power plant? Seems convenient.
They say energy use doubles but still somehow emissions drop. That doesn’t add up in my head. Like if they need more electricity, won’t fossil plants just burn more? Maybe the “clean electricity” part is gonna be like 20 years from now.
Basalt Portland cement… so we’re gonna quarry different rocks? Great, more mining. And “recovery of On the face of it” ??? what even is that, it got cut off or something. I’m not saying it won’t help, I just don’t trust another lab step that’s supposed to scale. Cost decides everything anyway like they admit, so who benefits first? Probably not regular people.