Executive Summary
This whitepaper examines the role of efficient CO₂ liquefaction in enhancing the sustainability and profitability of biogas plants across Europe. It outlines the components driving the business case, highlights regulatory and economic drivers shaping demand for biogenic CO2 through 2035 and describes the integrated biogas upgrading and CO2 liquefaction system: the CarboX®Fusion by DMT Environmental Technology. This is emerging as strategic enabler for biomethane projects seeking faster payback through quota-linked revenues, future-proofing against stricter Carbon Intensity (CI) thresholds in 2030+ and market access to the e-fuel value chain, where biogenic CO₂ is indispensable.
Introduction
Recent developments in legislation such as the implementation of the Renewable Energy Directive 3 (RED3), FuelEU Maritime, ReFuelEU Aviation and the upcoming IMO developments, offer new opportunities for biogas plants. Long-term incrementally increasing CO2-emission reduction targets make capturing the CO2 from a biogas upgrading system increasingly viable. DMT’s CarboX®Fusion technology is specifically designed to benefit from these developments by optimizing efficiency and thereby improving the carbon intensity (CI) of the produced biomethane.
1. Historical and projected development of total greenhouse gas emissions per sector from 2021-2045 (German Environmental Agency): Allowed GHG-emissions are decreasing year-on-year, improving the case for integrating biogas upgrading with CO2 liquefaction.
Building the business case: Current CO₂ Pricing & Market Dynamics
In 2025 Biogenic CO₂ is typically trading at ~€100/t in spot markets (European Biogas Association, 2024). CO2 is a very local market: In some areas and at some times of the year spot prices can exceed €100/t.
Building the business case: CI‑Score & Certificate Market Dynamics
Germany’s THG quota system obliges fossil fuel suppliers to meet increasing CO₂ reduction targets through 2035. The statutory buy‑out penalty is €600/t CO₂e, serving as a price cap but also a long‑term value anchor for Guarantees of Origin (GOs: green certificates).
In the Netherlands, a Carbon Intensity (CI)‑based Guarantee of Origin (GO) system for transport begins in 2026, followed by a larger system for the built environment and under ETS-2 from 2027, with a €450/t CO₂e buy‑out penalty.
Other EU-countries are developing legislation on the basis of the RED3, which lowers the maximum allowed CI-score for renewable gas to 32.9 g CO2e/MJ for transport and 16 g CO2e/MJ for heating and cooling applications.
The further updates of the EU gas decarbonization package are likely to encourage member states to adopt performance‑based obligations tied to Carbon Intensity by 2026.
Market Outlook & Regulatory Forecast (Future developments)
EU biomethane must scale from ~6 bcm in 2024 to 35 bcm by 2030 (REPowerEU, 2024). This drives demand for CO₂ capture (30–50 Mt/year by 2030) and quota‑linked GOs. By the early 2030s, certificate prices may trend toward €450–600/t, enabling €35–77/MWh additional revenue for the CI improvement or even more than that with carbon capture & storage (CCS) and carbon dioxide removal certificates (CDR). Producers integrating biogas upgrading and CO2 liquefaction technology can thus secure fast paybacks and future-proofed revenues.
CO2 prices are expected to rise as e‑fuel mandates from 2030 boost demand for sustainable carbon sources. E-fuel mandates are being implemented in the EU, primarily through the ReFuelEU Aviation and FuelEU Maritime regulations, to increase the use of renewable fuels of non-biological origin (RFNBOs), including e-fuels, in the transport sector. Specifically, the ReFuel EU Aviation regulation mandates that 1.2% of aviation fuel must be e-SAF (sustainable aviation fuel) by 2030, with a gradual increase to 35% by 2050. Similarly, FuelEU Maritime promotes 1% RFNBO use in maritime fuels by 2031. This while the supply of industrial CO₂ has come under significant pressure due to closures and production rollbacks at fertilizer and related chemical plants as well as due to carbon capture and storage in underseas basins.
CarboX®Fusion integrated biogas upgrading and CO2 liquefaction system (DMT Environmental Technology)
CarboX®Fusion System Overview
The most efficient way to upgrade biogas to biomethane and biogenic CO2, is CarboX®Fusion; an integrated biogas upgrading and CO₂ liquefaction solution designed for biogas plants. Its compact, energy-efficient design minimizes power consumption/OPEX and maximizes to 100% the capture efficiency for both CO2 and methane, lowering carbon intensity and enabling project developers to monetize CO₂ through industrial sales, carbon capture & storage (CCS), or e‑fuel markets.
It incorporates the proven Carborex MS biogas upgrading technology from DMT Environmental Technology, which has proven to be very reliable in 100+ production sites across Europe and North-America.
