C-Green
C-Green is a Swedish clean-tech company that commercializes Hydrothermal Carbonization (HTC) technology, converting wet biowaste into biocoal for industrial and waste-management customers such as pulp and paper mills, municipalities, and biogas producers.
- Company typePrivate
- Founded2014
- HeadquartersStockholm, Sweden
- Headcount11–50
- GTM typeB2B
- OfferingHardware or Manufacturing
What C-Green does
C-Green is a Swedish clean-technology company that commercializes Hydrothermal Carbonization (HTC), a thermochemical process that converts wet organic waste streams into biocoal (hydrochar). Headquartered in Solna, Sweden, and founded in 2014-2015, the company serves industrial and municipal customers that produce wet biowaste — including pulp and paper mills, waste-management firms, and biogas producers — enabling them to valorize biosludge that would otherwise require costly drying or disposal. The technology directly addresses circular-economy and Scope 3 decarbonization use cases for resource-intensive industries.
The company's core product is the OxyPower HTC process, delivered through modular, prefabricated plants. Its flagship deployment is a full-scale plant at Stora Enso's Heinola Flouting Mill in Finland, designed to process 30,000 tons of wet biosludge per year. The product portfolio has expanded to include BioBooster (an AI-based process analysis tool with PFAS-mapping capability), Design 3.0 (the latest modular plant architecture), and downstream forest fertilizer pellets that productize the hydrochar output. C-Green operates a capital-equipment business model with long-term service agreements, selling to enterprise customers on a project-by-project basis, supplemented by a partnership-driven go-to-market with engineering and waste-management counterparties such as Ragn-Sells and REYM Rotterdam.
The company is venture-backed, with disclosed funding of approximately SEK 95M+ across multiple rounds since 2018, supported by SEB Greentech, InnoEnergy, Almi Invest, Nordea Life & Pensions, and the Swedish Energy Agency. C-Green is in an early-commercial scaling phase: it has one operational full-scale plant and a development pipeline spanning Sweden, Finland, the Netherlands, Estonia, and India. Leadership comprises CEO Monika Schildknecht, CTO Staffan Jakobsson, and CFO Thomas Ranje. The core commercial challenge is converting the flagship reference into a repeatable sales pipeline beyond a small set of named anchor customers.
C-Green firmographics
Firmographics- Name
- C-Green
- Legal name
- C-Green Technology AB
- Website
- https://c-green.se
- Company type
- Private
- Founded year
- 2014
- Operating status
- Operating
- Headcount range
- 11–50 employees
- Short description
- C-Green is a Swedish clean-tech company that commercializes Hydrothermal Carbonization (HTC) technology, converting wet biowaste into biocoal for industrial and waste-management customers such as pulp and paper mills, municipalities, and biogas producers.
- Ownership category
- akta.pro rank
C-Green industry classification
Industry- Product category
- Sludge Treatment Systems
- NAICS
- Fertilizer and Compost Manufacturing (32531), Sewage Treatment Facilities (221320)
- SIC
- Chemicals & Allied Products (2800)
- akta.pro primary industry
- Biochar Carbon Projects (Biomass to Biochar & Soil Application) (EUABABAH)
- akta.pro secondary industries
- Wastewater Treatment Plant Biogas & CHP (EUACAIAE), Biomass & Waste-to-Energy Plant EPC (EUAEAAAI)
Keywords
Where C-Green is headquartered
LocationHeadquarters
- HQ city
- Stockholm
- HQ country
- Sweden
- HQ region
- Europe
Offices3 records
Markets served
C-Green business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Technology or R&D, Personnel, Operations, Supply Chain, Infrastructure, Marketing or Sales
Revenue model
- HTC Plant Equipment Sales and Licensing: C-Green sells and licenses its HTC technology to industrial partners, including full-scale plant installations. The company operates a full-scale plant at Stora Enso's Heinola Fluting Mill and has partnerships for circular sludge management with Ragn-Sells and others.
- HTC Biocoal Product Sales: Sale of HTC biocoal (hydrochar) produced from the HTC process, which can be used as biofuel, carbon sink, fertilizer, or soil improvement product. The biocoal has a heat value of approximately 10 GJ per ton (2.8 MWh/ton).
Go-to-market motion1 record
Distribution channels2 records
Marketing channels5 records
C-Green product offering
Product offeringCore offering
C-Green designs, manufactures, and licenses modular prefabricated Hydrothermal Carbonization (HTC) plants that convert wet biowaste and sludge into sterile HTC biocoal (hydrochar) at approximately 200°C in one hour. The company sells full-scale HTC plant equipment (up to 30,000 tons/year capacity), provides mobile pilot plants for sludge stream testing, and produces HTC biocoal that is sold as biofuel, carbon sink, fertilizer, or soil improvement product for industrial customers.
Product overview
C-Green offers a suite of HTC (Hydrothermal Carbonization) technology solutions for converting wet biowaste into sustainable biocoal. The core offering consists of the OxyPower HTC Process, which treats sludge at approximately 200°C to produce HTC Biocoal (Hydrochar). Plants are offered in modular, prefabricated configurations ranging from mobile pilot units to full-scale facilities processing up to 30,000 tons per year. The product portfolio includes branded offerings such as BioBooster for biogas enhancement, Design 3.0 as the latest plant generation, and an AI-based analysis tool for predictive process modeling. All solutions share the common foundation of converting wet organic waste into dry, sterile, carbon-rich biocoal with applications in energy, agriculture, and environmental remediation.
Differentiator
Problem solved
Functional benefit
Products and services
- HTC Biocoal (Hydrochar) A solid carbon-rich material produced through hydrothermal carbonization of wet biowaste. It is sterile, odorless, easy to handle and store, with greatly reduced volume and mass (up to 80% less) compared to untreated sludge. Has multiple applications including use as carbon sink, biofuel, fertilizer, and for soil improvement. Heat value approximately 10 GJ per ton (2.8 MWh/ton), 55-70% dry solid content.
- C-Green HTC Plants Modular, prefabricated HTC plants constructed as easily transportable ISO container-sized modules (20-foot or 40-foot). A standard main building with 25,000 tons/year capacity requires approximately 400 m2 with 8m height. Full-scale plants can process up to 30,000 tons of wet sludge per year. Designed for deployment at industrial sites including wastewater treatment plants and pulp mills.
- Mobile Pilot Plant A mobile pilot plant unit used for conducting tests on different sludge streams. Outgoing product streams (biocoal and HTC filtrate) are sent for external lab analysis and to potential off-takers, enabling customer evaluation of HTC processing before full-scale deployment.
Quantifiable outcome
- 80% reduction in transport volumes compared to untreated sludge
- +4 more outcomes
Companies that use C-Green
Customer profileNamed customers4 records
Segments3 records
Ideal customer profiles3 records
C-Green technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
AI capability2 records
Feature4 records
C-Green partnerships and signals
Strategic signalPartnerships
Five partnerships are on record, tiered flagship, core and minor.
- Stora EnsoflagshipFlagship partnership with Stora Enso at their Heinola Fluting Mill in Finland. C-Green built the world's first OxyPower HTC biofuel plant for sludge recycling at this site in 2019. The partnership involves ongoing collaboration for testing and upgrading the HTC technology, with C-Green's pilot unit conducting tests on different sludge streams. The plant processes industrial sludge from Stora Enso's operations.
- Ragn-SellscoreCollaboration on circular sludge management announced January 2023. The partnership aims to develop circular economy solutions for sludge handling. The first C-Green facility designed for sludge from wastewater treatment plants is planned at Häradsudden outside Norrköping.
- REYM RotterdamcorePartnership announced January 2022 for collaboration to reduce climate impact from industrial wet waste. REYM Rotterdam and C-Green launched a unique collaboration for processing industrial sludge using HTC technology in Rotterdam.
- Karlstad UniversityminorResearch collaboration with Karlstad University for testing pelletized HTC biocoal and ash mix as sustainable forest fertilizer. Together they are testing pellets for spreading in growing forests to evaluate potential as replacement for fossil-based forest fertilizers.
- Estonia's Largest Biogas ProducerminorPartnership announced December 2022 with Estonia's largest biogas producer for circular sludge treatment using C-Green's HTC technology.
Scale indicators7 records
Recent moves9 records
Expansion highlights5 records
C-Green competitors and assessment
Company assessmentDirect peers
- Terranova Energy: Terranova Energy operates HTC plants in Germany that convert sewage sludge into hydrochar for agricultural and energy use. It is the closest direct peer to C-Green, sharing both the HTC core process and the municipal-sludge target customer in Europe.
- Carbofex: Carbofex is a Finnish HTC-biochar producer serving agricultural soil amendment and carbon-removal markets. Comparable to C-Green in core hydrochar technology, Nordic footprint, and use of HTC for soil/carbon applications.
- Pyreg GmbH: Pyreg manufactures pyrolysis-based biochar plants sold to municipalities and agricultural operators in Europe. Comparable to C-Green as a biochar plant vendor with a similar carbon-removal and soil-amendment value proposition, though using dry pyrolysis rather than HTC.
Broad incumbents
- Veolia: Veolia is a global water and waste management incumbent operating municipal wastewater and sludge-treatment services across Europe. It is comparable to C-Green as both a potential partner and competitor offering integrated sludge handling to C-Green's target municipalities.
- Suez: Suez (now part of Veolia group structure) is a major European water/wastewater utility offering sludge treatment, recycling, and disposal services at scale. Relevant as an incumbent customer/procurement counterparty and a benchmark for large-scale municipal sludge infrastructure.
Emerging players
- CarbonOrO: CarbonOrO develops hydrothermal carbonization technology to convert wet organic waste streams into biochar and energy. Comparable to C-Green in applying HTC to industrial wet-waste feedstocks, though at an earlier commercial stage.
- Anaergia: Anaergia builds anaerobic digestion and waste-to-energy facilities for municipal and industrial organic waste, including sludge. Comparable as an adjacent waste-to-value technology provider targeting some of the same municipal and industrial customers as C-Green.
- Renmatix: Renmatix converts non-food biomass into sugars and bio-based intermediates using supercritical hydrolysis. Adjacent to C-Green as a thermochemical/biomass conversion technology company pursuing bio-based products from waste or residues.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat5 records
Key risks6 records
Key highlights7 records
Customer concentration
C-Green social profiles
Digital presenceC-Green compliance and trust
Trust signalCompliance1 record
C-Green financial estimates
Financial estimateRevenue estimate
Valuation estimate
C-Green leadership team
Management profileNumber of profiles
Profiles5 records
C-Green funding detail
Funding detailFunding overview
Funding rounds3 records
Investors2 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
C-Green M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about C-Green
What does C-Green do?
C-Green designs, manufactures, and licenses modular prefabricated Hydrothermal Carbonization (HTC) plants that convert wet biowaste and sludge into sterile HTC biocoal (hydrochar) at approximately 200°C in one hour. The company sells full-scale HTC plant equipment (up to 30,000 tons/year capacity), provides mobile pilot plants for sludge stream testing, and produces HTC biocoal that is sold as biofuel, carbon sink, fertilizer, or soil improvement product for industrial customers.
Is C-Green a public or private company?
C-Green is a private company. It is classified as venture growth investor backed and is currently operating.
When was C-Green founded?
C-Green was founded in 2014. It employs 11 to 50 people.
Where is C-Green based?
C-Green is headquartered in Stockholm, Sweden, in the Europe region.
How does C-Green make money?
Two revenue lines are on record. HTC Plant Equipment Sales and Licensing is the primary driver. The others are HTC Biocoal Product Sales.
Who are C-Green's main competitors?
Direct peers on record are Terranova Energy, Carbofex and Pyreg GmbH. Broad incumbents are Veolia and Suez. Emerging players are CarbonOrO, Anaergia and Renmatix.
Does C-Green have an API?
No public API is recorded for C-Green.
What industry is C-Green in?
C-Green's product category is Sludge Treatment Systems. Its primary akta.pro industry code is EUABABAH, Biochar Carbon Projects (Biomass to Biochar & Soil Application), with a secondary code of EUACAIAE, Wastewater Treatment Plant Biogas & CHP. Its NAICS code is 32531 and its SIC code is 2800.