Latest / The Manufacturing Podcast with Fexingo: Factories, Supply Chains, and Industrial Business / How a Dutch Factory Turns Greenhouse CO2 into Baking Soda
Transcript
- Lucas: There is a factory in the Netherlands that takes waste carbon dioxide from a greenhouse and turns it into baking soda. Not a pilot plant, not a lab experiment — a commercial factory that has been running since 2022 and made about 15,000 tons of the stuff last year. Luna: Wait — baking soda as in the orange box in my pantry? That baking soda? Lucas: Exactly that. Sodium bicarbonate. Same chemical. But most of what this factory produces doesn't end up in cookies — it goes into laundry detergent, animal feed, and industrial water treatment. The company is called NedCarbon, and the plant sits right next to a massive greenhouse complex in the province of South Holland. Luna: And the CO2 comes from the greenhouse itself? I thought plants absorbed CO2. Lucas: They do, during the day. But at night, when photosynthesis stops, greenhouses often vent CO2 from their heating systems — natural gas boilers — straight into the atmosphere. This particular greenhouse uses combined heat and power, so it's emitting a concentrated stream of CO2. NedCarbon pipes that off-gas through a two-kilometer line into their reactor building. Lucas: Inside the reactor, they bubble the CO2 through a solution of sodium hydroxide — what you'd know as caustic soda. The reaction is actually straightforward: CO2 plus sodium hydroxide gives you sodium bicarbonate and water. No catalysts, no exotic temperatures. Standard industrial chemistry you could look up in a 10th-grade textbook. Luna: So why isn't every greenhouse doing this? It sounds almost too simple. Lucas: The simplicity is real, but the economics have only worked recently. Sodium hydroxide isn't free. The energy to run the pumps and dryers isn't free. And the selling price of baking soda is around €200 to €250 per ton for industrial grade. For years, it was cheaper for greenhouses just to vent the CO2 and buy baking soda from conventional sources — mined trona ore from Wyoming or synthetic production from limestone. Lucas: What changed is the carbon price. Under the EU Emissions Trading System, that greenhouse was paying roughly €80 per ton of CO2 emitted in 2023. By late 2025, the price was flirting with €150 per ton. Suddenly, capturing the CO2 and selling it as baking soda starts to make financial sense — especially if you can sell the bicarbonate at a small premium as 'low-carbon' or 'circular'. Luna: So the carbon price is the real driver here, not the technology. Lucas: Exactly. The chemistry has been known since the 1800s. The innovation is the business model — and the fact that the pipeline is only two kilometers long. Transporting CO2 over long distances is capital-intensive and politically contentious. But if your CO2 source and your conversion plant are next door, the infrastructure cost drops dramatically. Luna: And you mentioned this isn't their only product. What else comes out of that plant? Lucas: They also produce sodium carbonate — soda ash — which is used in glass making and detergents. By controlling the temperature and concentration in the reactor, they can shift the output between bicarbonate and carbonate. That flexibility matters because the market for soda ash is much larger — roughly 50 million tons globally per year — but it's also more price-competitive. The bicarbonate market is smaller but commands higher margins. Lucas: NedCarbon's plant is designed to produce about 20,000 tons annually when running at full capacity. They hit about 15,000 last year, which means they captured roughly 7,000 tons of CO2 that would have gone up the greenhouse's stack. That's not huge in absolute terms — a typical coal plant emits that in a few days — but it's a proof point for distributed carbon capture at agricultural sites. Luna: And their biggest customer? You said detergent industry, not food. Lucas: Right. Food-grade baking soda has to meet strict purity standards — no heavy metals, no residual caustic. That requires extra processing steps and certification. Industrial grade is less demanding. Their main buyer is a European detergent manufacturer that uses sodium bicarbonate as a water softener and pH buffer in laundry powders. It replaces sodium tripolyphosphate, which is a pollutant in waterways. Luna: That's actually a nice angle — the baking soda itself is solving a different environmental problem downstream. Lucas: Exactly. And that's the kind of circular logic that makes this plant more than a carbon capture gimmick. The bicarbonate is displacing phosphates, which cause algae blooms. The CO2 is from a greenhouse that would otherwise pay to emit it. The only input that isn't recycled is the sodium hydroxide, but that's produced using chlorine — and there's ongoing work to produce that from salt using renewable electricity. Lucas: If these conversations have moved your work forward in some small way, here is the thing — we deliberately don't run ads on these episodes. No sponsors, no pre-rolls, no affiliate links. That is a choice we made when we started the show, and it means the only thing supporting it is listeners who find it useful. Luna: Yeah, and it is genuinely the only reason the show exists the way it does. If that model works for you, the link is buy me a coffee dot com slash fexingo. No pressure at all. Lucas: And back to the factory — one detail I find fascinating is that the reaction itself produces heat. When you bubble CO2 into caustic soda, the temperature rises. NedCarbon captures that waste heat and uses it to dry the bicarbonate crystals. So the plant's energy intensity is lower than a conventional baking soda plant that has to fire a kiln. Luna: Right — so they're getting heat recovery from the chemistry itself. That's clever. Lucas: It is. And it shaves about 15 percent off their operating costs compared to a standard Solvay-process plant. That matters because the profit margin on industrial bicarbonate is thin — maybe 10 to 15 percent at current prices. Every efficiency gain is material. Luna: How many similar plants could exist? Is this replicable beyond Dutch greenhouses? Lucas: There are roughly 3,000 hectares of greenhouse agriculture in the Netherlands alone, most of them heated by natural gas. If you assume each hectare emits about 50 tons of CO2 per year from heating — that is a rough number — you get a potential capture volume of 150,000 tons per year just from Dutch greenhouses. That is enough to feed maybe 8 to 10 plants the size of NedCarbon's. Lucas: Globally, the opportunity is larger but more diffuse. In Spain's Almeria region, you have 30,000 hectares of greenhouses, but they use much less heating because of the climate. In Canada, there is a growing greenhouse sector using geothermal and natural gas. The model works best where you have concentrated CO2 from a point source and a nearby market for bicarbonate. Luna: What about the sodium hydroxide supply? That's not exactly a green chemical. Lucas: Fair point. Most sodium hydroxide is made via the chlor-alkali process, which uses electricity and produces chlorine as a co-product. If the electricity is from fossil fuels, the carbon footprint of the hydroxide can offset the capture benefit. NedCarbon sources its hydroxide from a plant that uses hydroelectric power, so the overall balance is positive. But that's a constraint — not every location has access to low-carbon caustic soda. Lucas: There is also a startup in Belgium called CO2-to baking soda that uses a different route — they react CO2 with brine and ammonia in a modified Solvay process. They claim they can avoid the caustic soda entirely by recycling the ammonia. I think they are at pilot scale now, targeting 2027 for a commercial plant. Luna: So the field is moving, but the Dutch plant is the one that's actually making money today. Lucas: Yes. And that matters because carbon capture has a credibility problem. A lot of projects are announced, few are built, and even fewer operate profitably. NedCarbon is not huge, but it's real. It pays its bills. It sells a product people actually buy. That is the kind of proof the sector needs. Luna: One thing I'm curious about — the greenhouse itself. Are they getting any benefit beyond avoiding the carbon tax? Does the CO2 capture affect their operations? Lucas: The greenhouse owner, a company called Duijvestijn, gets a lower carbon bill and a fixed-price revenue stream from NedCarbon for the captured CO2. But there is a nuance: the greenhouse still needs CO2 during daylight hours for plant growth. The pipeline runs both ways — during the day, some of the CO2 from the boiler goes directly into the greenhouse. At night, when the vents are open and no CO2 is needed, it goes to the factory. So the two operations complement each other without conflict. Luna: That is actually a smarter design than I imagined. It's not just a one-way pipe. Lucas: Right. And it's a reminder that industrial symbiosis often requires that kind of choreography. You can't just bolt a carbon capture unit onto any facility and expect it to work. You need to match the timing, the purity, the volume. The Dutch greenhouse case is unusually clean because the CO2 stream is already high-concentration — about 95 percent after the flue gas is scrubbed — and the demand is nearby. Lucas: NedCarbon's founders, by the way, came from the chemicals industry, not from carbon capture. They had worked in soda ash production and saw the opportunity when the EU carbon price started climbing. That background shows — they optimized the process for yield and energy, not just for carbon removal. Luna: That might be the most important lesson for listeners thinking about carbon capture. If you approach it as a chemical business, not a climate project, you are more likely to build something that lasts. Lucas: Exactly. And if the carbon price stays above €100 per ton — which most analysts expect — then the economics will only improve. NedCarbon is already talking about a second plant in the province of Limburg, connected to a sugar beet processing facility. Sugar fermentations produce CO2 too, and the caustic soda route works the same way. Luna: Will they announce that this year? Lucas: They haven't said publicly yet. But if the financing comes together, it would be a strong signal that the model is scaling. One plant is an experiment. Two plants in different industries is a template. Lucas: I think the most encouraging part is that the technology is so boring. No fusion, no quantum, no exotic materials. Pipes, pumps, tanks, and a simple acid-base reaction. That's what industrial decarbonization looks like when it works — not a breakthrough, but a business model that finally becomes viable because the incentives line up. Luna: Boring is good in manufacturing. Boring means reliable, maintainable, financeable. Lucas: Exactly. And that is why this factory in a Dutch greenhouse district might matter more than any fancy carbon capture startup you read about. It's running. It's making money. And it's selling baking soda.