Calcined Clay: CemGreen Took Its EIC Accelerator Kiln to CRH

Cement is made by heating crushed limestone to 1,450°C, and half of the carbon dioxide it emits comes from the chemistry of the limestone itself rather than the fuel, according to a Danish Environmental Protection Agency report. One way to cut those emissions is to use less cement in concrete and replace part of it with a supplementary cementitious material (SCM). The main substitute has been fly ash from coal power stations, which is becoming scarce as those plants are phased out, the CORDIS project summary notes. CemGreen, a small Danish company, bet on heated clay minerals, and on a kiln of its own design to heat them.

In the European Innovation Council's May 2020 Green Deal cut-off, CemGreen was one of the Danish winners, listed in the Commission's list of selected companies as a Roskilde company with "blended finance" for CemShale CemTower. No other company is listed for the project. CORDIS records an EU grant of €1,517,699 towards a total cost of €2,168,142.36, from 1 October 2020 to 31 March 2023. At the time, the company's filed accounts show no employees in 2019 and one in 2020.

Where CemGreen Stands Now

CemGreen is active. It filed its 2025 annual report on 30 June 2026, and in September 2026 it registered a new board, chaired by founder Lasse Nørbye Døssing, according to North Data. The registered office moved from Roskilde to Humlemarken 2A in Hobro, North Jutland, in January 2024, where the company's website places its workshop, laboratory and the CemTower pilot plant. The website describes CemGreen as a supplier of equipment for the cement and concrete industry, offering engineering, procurement, commissioning and plant automation, and says "the first CemTower plant in operation" is run by NovaClay A/S, a joint venture between CRH and CemGreen.

That plant sits on Viborg Landevej 1 in Hobro. NovaClay was registered in June 2022 as CemGreen Denmark A/S by CemGreen ApS and CRH Denmark A/S and took its current name in July 2024, according to North Data. Its 2025 annual report names CRH Denmark A/S as parent company and says the company "brought property, plant and equipment under construction into use" in January 2026. CemGreen's own 2025 accounts list its stake in NovaClay at 40%. NovaClay's product, also called NovaClay, has been certified under the Danish concrete standard DS/EN 206 for exposure classes up to XF1, which covers most ordinary buildings but not bridges, roads or marine structures, the company said on its website in October 2025.

The Technology: A Kiln Stood on Its End

Clay minerals have no cement-like properties in their natural state. Heated to the right temperature, they lose their bound water and become reactive, so that the silicon and aluminium in them combine with the calcium hydroxide released by hydrating cement. Overheat them and the result is inert; the iron in them oxidises and turns the product red, as the Danish EPA report explains. A February 2026 presentation to the Danish Concrete Association by Gunnar Hansen (North Data lists a Gunnar Jan Hansen as NovaClay's director until January 2026) describes the NovaClay process: clay from Danish pits is kneaded and formed into uniform pieces, heated to about 700°C and ground finer than cement.

CemGreen's two ideas are in the project title. CemShale was a process to calcine shale in granules rather than as a powder, which the company says limits overburning and discolouration. CemTower is a unit that stacks the preheater, kiln and cooler of a conventional plant into one vertical tower, which the CORDIS report says cuts operating costs compared with SCM production in "conventional rotary kilns or complex cyclone solutions". The company's emissions claims vary by source: the CORDIS report says its SCM has "98% lower CO2 emission rates" than cement production, while the 2024 Saudi announcement, reported by Gulf Construction and the Middle East Observer, cites 8 kg of CO2 per tonne of calcined clay. No independent measurement of either figure was found.

What the EIC Project Promised, and What CORDIS Shows

The CORDIS objective promised a 10-tonne-a-day CemTower pilot plant, preparation of a 500-tonne-a-day demonstration plant, patents and partnership agreements, and "~650+ new jobs already within 5 years of commercialisation". It put the market at €63 billion and said full adoption could cut worldwide CO2 emissions by 4.81%, a figure the later report lowers to "approx. 3%".

The single periodic report on CORDIS is headed as covering 1 October 2021 to 31 March 2023, but its text describes the work as it stood in mid-2021: the pilot plant erected, cold commissioning "expected to be concluded towards the end of September, 2021", and talks with "a major EU-based global stakeholder" that could co-fund the demonstration plant. No final results, deliverables beyond a note on patent filings, or publications are listed on the results page.

The missing results can be filled in partly from Danish sources. A report published by the Danish Environmental Protection Agency in October 2022, on a separate MUDP grant to CemGreen, says the pilot ran 15 test runs and then four continuous runs of 16 hours that processed 40 tonnes of raw material, and that mortar in which calcined clay replaced 35% of the cement showed stable, high compressive strength. It says that after that project CemGreen signed an agreement with CRH Group to build a full-scale CemTower plant, and that it had been granted a further MUDP lighthouse grant for that plant. The size of that grant could not be verified.

1. 10 t/day CemTower pilot plantDeliveredErected per CORDIS; 40 tonnes processed in continuous runs per the Danish EPA report.
2. Prepare a larger demonstration plantLate, via partnerNovaClay's Hobro plant went into use in January 2026, after the project; its capacity is not public.
3. CemShale as a shale-based SCMNot deliveredProcess switched to clay (CemClay); no shale-based product announced.
4. Patents and partnershipsDeliveredPatent applications listed on CORDIS and North Data; joint venture with CRH Denmark.
5. 650+ jobs within 5 yearsNot delivered9 average staff at CemGreen and 14 at NovaClay in 2025.
6. Final reportingNot publishedThe only CORDIS report describes the state of mid-2021.

What CemGreen Has Achieved Since the Award

The core of the record is the CRH deal. CRH Denmark controls the joint venture and financed most of the plant: NovaClay's 2025 balance sheet shows DKK 229.9 million owed to group companies, against DKK 206.2 million of plant under construction. The joint venture lost DKK 4.5 million in 2024 and DKK 12.7 million in 2025, leaving equity of minus DKK 16.5 million; its auditors note a letter of support from the majority shareholder valid until 31 December 2026. CemGreen's 2025 accounts report NovaClay's equity at minus DKK 16.6 million and its result at minus DKK 12.8 million, slightly different from NovaClay's own filing.

A second licence followed abroad. In October 2024 Nizak Mining Company, a subsidiary of the listed Saudi producer City Cement, and the UK's Next Generation SCM announced a joint venture to bring CemTower to the Gulf, with a first plant in Riyadh planned to start mass production in the third quarter of 2025 at 350,000 tonnes a year, rising to 700,000 tonnes, according to Gulf Construction and the Middle East Observer. City Cement's 2025 annual report says Next Generation SCM holds "usufruct rights to patented technology developed by Danish firm CemGreen" and that Nizak "commenced operations in 2025, generating total sales revenue of approximately SAR 17.36 million". It does not say whether a CemTower line is producing calcined clay, and that could not be verified.

CemGreen's own accounts show the business growing from a near-empty shell. Total assets rose from DKK 417,441 in 2019 to DKK 54.4 million in 2025, and cash to DKK 14.9 million. The 2025 balance sheet records DKK 42.8 million of payments received on account for contract work, with contract work in progress of DKK 17.9 million recognised, which shows CemGreen selling plant engineering to a customer; the accounts do not name it. North Data also lists state aid of DKK 4,709,985 in 2024 and DKK 4,737,510 for 2026 to 2028 under Denmark's Innobooster programme; no second source for those grants was found.

The team is still small. The filed accounts show one employee on average from 2020 to 2023, three in 2024 and nine in 2025. The company website gives a staff of about 30, a number the accounts do not show.

The Money

CemGreen has made small profits in every year since the award except 2023, and its equity rose from DKK 1.0 million at the end of 2020 to DKK 6.3 million at the end of 2025. No equity round was found. The award was listed as blended finance, but CORDIS shows only the grant, and CemGreen does not appear among the 319 organisations on the EIC Fund's list of invested companies. Its shareholders on record are holding companies of its founders and managers, according to North Data.

Why Europe Should Care

Cement is one of the six sectors covered by the EU's Carbon Border Adjustment Mechanism, whose definitive regime began on 1 January 2026, so the carbon content of cement now carries a price at the border as well as inside the EU. Clay is local, which matters more as fly ash disappears with coal power: NovaClay sources its clay from Danish pits, according to its 2025 sustainability statement. Denmark only allowed calcined clay as an SCM in concrete under its standard from 1 July 2024, according to the Danish Concrete Association presentation.

The commercial value has so far gone to a large incumbent. The plant belongs to a joint venture controlled by CRH, and the Saudi rights sit with a British company. The scale-up the EIC funded is visible mainly in other companies' accounts.

The Verdict

CemGreen has not been asked for comment for this article. It is based entirely on public records, company statements and EU project data, linked throughout. The origin of the company is reported differently: its website calls it a spin-out of a University of Copenhagen research project, while the Danish EPA report says preliminary studies were carried out in a research project at DTU.