The lime kiln at the Energy & Environmental Research Center in North Dakota stands more than seven stories tall, a hulking piece of industrial plumbing that looks like it belongs in a cement plant. It is, in fact, a testbed for something far more ambitious: turning one of the world’s most carbon-intensive materials into a machine for pulling CO2 out of thin air.
Origen Carbon Solutions, a UK-based startup founded in 2013, has spent over a decade refining its proprietary oxyfuel kiln technology. The goal is simple, if audacious: make lime, a foundational material for steel, construction, and water treatment, with zero process emissions. Then, use the same chemical cycle to capture atmospheric carbon. In January, the company announced the results from that North Dakota demonstration, reporting the kiln consistently achieved greater than 99% conversion of limestone to lime in a CO2-rich environment, exceeding performance targets [World Cement, Jan 2026].
The chemistry of turning a problem into a solution
Origen’s bet hinges on the lime cycle, a well-understood chemical reaction. Heating limestone (calcium carbonate) produces quicklime (calcium oxide) and releases pure CO2. In a conventional kiln, that CO2 is vented to the atmosphere. Origen’s oxyfuel kiln burns fuel in pure oxygen, creating a stream of exhaust that is almost entirely CO2 and water vapor, which is easily separated. This allows the CO2 from the limestone itself to be captured as a pure, pressurized gas [LinkedIn, retrieved 2024].
The quicklime produced is then "slaked" with water to make hydrated lime. This material is highly reactive with CO2 in the air. Spread it on fields or in simple reactors, and it will naturally re-absorb carbon dioxide over time, reverting back to limestone. It’s a closed-loop, mineral-based form of direct air capture that uses an existing global commodity as its engine [CO2 Value Europe, retrieved 2024].
The core commercial proposition rests on three pillars:
- A drop-in replacement. The technology is designed to be compatible with today’s lime supply chains, aiming to retrofit or replace existing kilns [LinkedIn, retrieved 2024].
- Dual revenue streams. Origen could sell zero-carbon lime at a premium, while also generating and selling carbon removal credits.
- Strategic use. By embedding itself in lime production, it builds a capital-efficient foothold in the larger carbon removal market.
Why Shell and Barclays are writing checks
The $13 million Series A round led by Barclays Climate Ventures in January 2025 was a vote of confidence from industrial and financial incumbents [Origen Carbon, Jan 2025]. Shell Ventures is also an investor, and Origen is working with the energy giant on its Pelican Direct Air Capture Hub on the Gulf Coast, a project that aims to eventually eliminate around one million tonnes of CO2 annually [Shell Global, retrieved 2026]. Another backer, Mississippi Lime Company, is one of the largest producers in North America.
| Metric | Value |
|---|---|
| 2018 Seed | Undisclosed |
| 2023 Seed | 0.142 M USD |
| 2025 Series A | 13 M USD |
The team bridging academia and heavy industry
Origen’s leadership reflects its dual identity as a deep-tech pioneer and an industrial project developer. Chief Scientist and co-founder Tim Kruger ran the Oxford Geoengineering Programme for over a decade and is a co-author of The Oxford Principles [Net Zero Climate, retrieved 2026]. CEO Ben Riddle-Turner, who joined in 2019, brings the commercial heft. A former investment banker, he has led the company’s global expansion, fundraising, and partnership efforts [Origen Carbon, retrieved 2026]. The team has grown to between 11 and 50 employees as it moves toward commercialization [Tracxn, Jul 2025].
The road from pilot to plant
The successful North Dakota test de-risks the core technology, but the path to commercial impact is measured in tons of lime and tons of CO2. The Singleton Birch project in the UK will be the next critical milestone, proving the technology at a scale relevant to industry. The main construction for that zero-carbon kiln was finished in mid-2022, with the company now focused on commissioning and testing [Invest Humber, retrieved 2026].
The economics of carbon removal are still being written. Origen must prove its process is not only technically sound but also cost-competitive. The capital expenditure for an oxyfuel kiln is higher than a traditional one, and the operational costs of oxygen production add another layer. The business case, therefore, leans heavily on the value of avoided carbon liabilities and sold removal credits.
The incumbent it must beat
Origen’s most direct competition isn’t another startup; it’s inertia. The global lime industry is fragmented, conservative, and operates on thin margins. Convincing a plant manager to rip out a functioning, depreciated kiln for a new, more complex system is a monumental sales challenge. The company’s partnership strategy with producers like Singleton Birch and backers like Mississippi Lime is explicitly designed to overcome this by sharing risk and aligning incentives.
Among pure-play carbon removal companies, Heirloom Carbon also uses a mineral-based process. Origen’s bet is that by anchoring its technology in an existing, essential industrial process, it can achieve scale and credibility that standalone DAC plants struggle to match. The company is now fundraising to extend its runway into 2027. The next twelve months will be about moving from a validated pilot to a financed, operating facility that produces both lime and verifiable carbon credits.