Mantel Raises $18M From Constellation and Azimut, Bringing Total to $50M for Carbon Capture Scale-Up

Mantel Capture has raised an $18 million strategic investment from Constellation Technology Ventures and Azimut Investments, with participation from existing investors, bringing the company's total funding raised to $50 million. The Cambridge, Massachusetts-based company develops molten-borate carbon capture technology and is advancing commercial deployment projects spanning power generation, oil and gas, and pulp and paper across North America, with plans to expand into Europe and other regions.

 

Why the Modular, Systems-Engineering Approach Targets a Well-Documented Failure Pattern

 

Mantel explicitly positions its approach as distinct from prior generations of carbon capture projects, which the company says "struggled with cost, scale, and complex on-site integration." That framing points to a genuine and widely documented pattern in the carbon capture industry: many earlier large-scale carbon capture projects, particularly those retrofitted onto existing power plants, faced substantial cost overruns and technical integration challenges specific to each individual site's unique infrastructure, since capturing carbon from an existing industrial facility typically requires customised engineering to interface with that facility's specific equipment and processes rather than a standardised, repeatable installation.

Mantel's stated modular, systems-engineering-led approach aims to reduce that site-specific customisation burden by designing a more standardised capture system capable of integrating into existing industrial infrastructure with less bespoke engineering per installation, an approach that, if successful, could meaningfully reduce both the capital cost and deployment timeline for each new project compared with the largely custom-engineered carbon capture retrofits that have characterised the industry historically.

 

Why Constellation's Involvement Signals More Than Financial Backing

 

Constellation Technology Ventures, the venture arm of Constellation, which the release describes as the largest producer of clean and reliable energy in the US, brings a different kind of credibility to this investment than a purely financial venture capital firm would. As an actual operator of power generation infrastructure at scale, Constellation's investment suggests the company sees genuine potential for Mantel's technology to integrate into real-world power sector operations without compromising the reliability standards utility operators must maintain, a technical and operational endorsement distinct from the kind of validation a pure financial investor's capital alone would signal.

Constellation's Kate Norman specifically framed the investment around technologies that balance "sustainability and reliability," language that reflects the central tension carbon capture technology must resolve for power sector adoption: any carbon capture system integrated into an operating power plant must not meaningfully compromise the plant's ability to reliably generate electricity on demand, since grid reliability requirements leave little tolerance for capture technology that introduces operational risk or reduces plant availability.

 

UPCOMING WEBINAR

AI academy: Two real ESG workflows saving days of manual work

Online, 03 September 2026 · Turning days of emissions data work into minutes with audit-ready AI workflows

 

What the Named Project Portfolio Reveals About Actual Commercial Diversity

 

Mantel's disclosed deployment portfolio includes a project with one of Canada's largest oil and gas producers, selection as the carbon capture technology partner for the 1.6-gigawatt TerraSpark Energy Campus in West Virginia, and deployment at Kruger's Wayagamack pulp and paper mill in Québec. That combination spans three genuinely distinct industrial sectors, oil and gas, power generation, and pulp and paper manufacturing, each with different emissions sources, facility configurations, and capture integration requirements, giving Mantel's stated cross-industry ambition concrete, named evidence rather than remaining purely aspirational.

Selection as the technology partner for a 1.6-gigawatt facility specifically represents a meaningful scale commitment, since a project of that size would require Mantel's technology to perform reliably across a considerably larger capture volume than a smaller pilot or demonstration deployment, making this project a significant test of whether the company's modular approach genuinely scales to large power generation facilities as intended.

 

Why the Azimut Partnership Signals International Expansion Ambitions Specifically

 

Azimut Investments' role is explicitly framed around providing access to global capital markets and project finance expertise to support Mantel's expansion beyond North America into new geographies, a distinct function from Constellation's more North American power sector-focused involvement. That structure suggests Mantel is deliberately building out financing relationships tailored to different phases and geographies of its growth, domestic power sector credibility through Constellation, and international project finance capability through Azimut, rather than relying on a single investor type to support what the company describes as multi-continent deployment ambitions.

 

What Comes Next

 

Chief executive Cameron Halliday framed the investment round around execution speed, stating "this moment is about execution and how fast we can build," positioning the company's current priority as commercial deployment velocity rather than further technology development or validation. Whether Mantel's modular approach successfully reduces the cost and integration complexity that has historically challenged carbon capture projects once deployed at the scale of the TerraSpark Energy Campus and its other named projects, and whether the company's international expansion supported by Azimut's project finance expertise proves as replicable in European and other markets as its current North American deployments, will determine how significantly this funding round advances Mantel's stated ambition to scale carbon capture across power generation and heavy industry more broadly.