Soda ash is invisible, essential, yet critical

Solar glass, batteries, water treatment, and even everyday products all have one thing in common: sodium carbonate, or soda ash. This is one of the most strategic and least visible materials of the decade ahead. It can be produced cheaply, in compliance with environmental rules that vary enormously from one continent to the next. Solvay, which invented the industrial process 160 years ago, is betting that Europe can still make it cleanly, under the world's strictest rules, if the continent gives its industry the regulatory stability to make that bet pay off. 

Try this test: ask ten people to name a material essential to the energy transition. You'll hear lithium, copper, silicon, maybe cobalt. No one will say soda ash. Yet without it, there is no glass for solar panels, no lithium carbonate for batteries, and no kidney dialysis either. Sodium carbonate is present in every moment of modern life without ever being named. And behind that invisibility lies a question rarely asked: under what conditions is a material so central to our low-carbon future actually made? 

Sodium carbonate is mainly produced in two ways. The first is direct extraction: trona, largely found in the United States and in smaller quantities in Turkey and China. The second is a chemical process, developed by Ernest Solvay in 1863 from salt and limestone, and still the basis of production in Europe. Solvay is one of the few producers that runs both technologies at scale, with a synthetic base in Europe and a trona operation in Wyoming, part of the roughly 13.9 million metric tons the US produces each year. There is also a modified version of this process, commonly known as the Hou process, which is dominant in China.

Étienne Galan, President of Solvay's Soda Ash & Derivatives business, is emphatic that this isn't a choice between the two. “We need an industry that runs on both trona and salt,” he says. The reason is straightforward: known trona reserves, while substantial, are concentrated in a handful of locations and are not limitless. In Turkey, the leading operator estimates its own reserves lasting between 20 and 30 years. Which is why Solvay has kept investing in both approaches for decades rather than betting the business on either one alone.

China accounts for approximately half of the 71 million metric tons of sodium carbonate produced worldwide in 2025, with 52 million metric tons of the synthetic variety and 19 million metric tons of its trona counterpart¹. The country has increased its capacity by more than 7 million metric tons per year since 2023, driven notably by the ramp-up to full capacity of trona-based soda ash in Inner Mongolia and the expansion of synthetic capacity. This supply growth contributed to tipping the global market into overcapacity in 2025. For 2026, leading market analysts project continued sluggish global demand growth, around +0.5%, while global net capacity is set to rise by approximately 2 million metric tons². Turkey adds its own pressure, with direct access to trona and a carbon constraint far lighter than Europe's.
 

Europe, for its part, imposes demanding CO₂ regulations on itself, along with an embargo on Russian gas or coal as well as Iranian gas that its Turkish competitors don't have to observe. “A significant portion of our costs depend on energy” notes Cristiano Fummi, Executive Vice President of Solvay's Soda Ash business. Decarbonize, pay more for energy, and stay competitive: three requirements that Europe requires from its industry all at once, when none of its competitors carries more than one of them at a time. 

There are no more soda ash plants in the United Kingdom: there used to be two. There are none left in Portugal, nor in Romania. Poland, which had two, now has only one. Far from being a temporary correction, these closures point to a deeper trend: an industry retreating from Europe, plant by plant, on a continent that otherwise continues to consume glass, batteries, and bicarbonate-based medicines in stable quantities. 

Unlike industries that could absorb a downturn and later restart a line, soda ash production is a heavy, capital-intensive infrastructure business that doesn't come easily back online once it's shut down. If a closure risks being permanent, a deeper question is raised: if Europe's production, the most tightly regulated in the world, gives way to supply made elsewhere under far looser rules, what has actually been gained for the climate?
 

Faced with challenging market conditions, characterized by worldwide oversupply and the sustained high energy and carbon costs in Europe, Solvay chose to cut capacity at its Spanish plant in Torrelavega. It's a choice for resilience, not retreat. The Belgian group is now taking a more assertive stance on the issue. Long known as European chemistry's discreet “gentleman,” settling matters behind closed doors, Solvay says it is ready to defend its position more openly, without abandoning its methods. 

Solvay's response isn't built around a single technology. It runs through the energy mix first: biomass in Germany, waste-derived fuel in France, exiting coal in the United States. Solvay Soda Ash business thus counts the highest number of decarbonization projects across its industrial sites. 
 

Further out, a pilot electrochemical process called e.Solvay, a nod both to electrification and to founder Ernest Solvay, aims to cut CO₂ emissions by 50%, limestone use by 30%, and energy and water consumption by 20% compared with the current process. A pilot is already running in France, with a >10k metric ton industrial prototype as the next step.
 

Galan is candid about the economics. “We are investing in putting a new engine in the same car, swapping legacy for longevity” he acknowledges. “Finding the returns to invest, without earning more: that's already something of a paradox in itself.” That paradox rests on one specific condition: decarbonized electricity, available at a comparable price in every European country where Solvay operates. A condition that, today, doesn't yet exist anywhere on the European continent. e.Solvay is one proof point in a longer transition, not a single fix expected to settle the argument on its own. 

What ties these bets together isn't a single technology. It's time. A company can commit capital over ten, fifteen, or twenty-five years. It cannot guarantee that regulation or energy prices will hold steady over that same period. That is precisely what Solvay is asking of Europe: predictability, not charity. "The decisions we make today will have effects over the next 10, 15, 20 years." Étienne Galan points out.
 

And that, implicitly, is where the entire future of the continent's glass industry is at stake.

^{1  World Analysis – Soda Ash  - Chemical Market Analytics}

^{2  The Evolving Global Soda Ash Landscape  - Chemical Market Analytics}