Arjun-backed Bigadan supplies CO₂ in first-of-its-kind industrial-scale carbon storage value chain

• CO₂ from Bigadan’s Kalundborg Bioenergy plant has been permanently stored beneath the North Sea through the INEOS-operated Greensand facility

• The milestone demonstrates a complete commercial pathway from biogenic CO₂ capture at a biogas plant to permanent offshore storage, establishing a model for wider deployment.

• It follows the opening of Bigadan's third CO₂ capture facility, taking annual capture and liquefaction capacity to more than 56,000 tonnes, serving permanent storage and industrial use.

Arjun Infrastructure Partners announces that biogenic CO₂ captured at its portfolio company Bigadan’s Kalundborg Bioenergy plant has been permanently stored below the Danish North Sea, through the INEOS-operated Greensand facility. The milestone connects Bigadan’s established biogas operations with commercial offshore carbon storage. Greensand, the EU’s first full-scale CO₂ storage site, was formally opened on 18 September by King Frederik X of Denmark, at a ceremony attended by senior European and Danish policymakers.

Bigadan converts agricultural, household and industrial organic waste into renewable gas and nutrient-rich biofertiliser, providing essential waste treatment services while displacing fossil gas and returning valuable nutrients to agriculture. Bigadan’s integrated model combines organic waste treatment, renewable energy production and permanent carbon removal, advancing circular economy and decarbonisation objectives while strengthening energy security.

Bigadan holds a contract awarded by the Danish Energy Agency to capture and permanently store biogenic CO₂, placing it at the start of the Greensand value chain. During biomethane production, CO₂ is separated, captured and liquefied at Kalundborg Bioenergy, then transported using biogas fuelled tankers to storage at the Port of Esbjerg and from there loaded onto Carbon Destroyer 1 for delivery to the Nini West reservoir, a depleted oil field roughly 1,800 metres beneath the seabed.

Biogenic CO₂ that would otherwise enter the atmosphere is permanently stored, enabling the generation of high-quality, traceable carbon removal credits. A 2024 assessment indicated that durable carbon removal solutions such as these need to scale approximately 1,000-fold by 2050, requiring urgent investment alongside deep emissions reductions.

Greensand is operated by INEOS Energy alongside Harbour Energy and Nordsøfonden. Its first commercial phase can store up to 400,000 tonnes of CO₂ annually, with potential to reach between four and eight million tonnes a year as the market develops.

The milestone comes as Europe expands both biomethane production and carbon storage infrastructure. The European Union is targeting annual biomethane production of 35 billion cubic metres by 2030, while Denmark expects renewable gas to meet the equivalent of its entire gas consumption by the end of the decade.

In part to address this demand for biogas and carbon storage, Bigadan opened its third CO₂ capture and liquefaction facility at Herning Bioenergy earlier this month. The facility can capture 12,000 tonnes of biogenic CO₂ annually, taking Bigadan’s total capacity to more than 56,000 tonnes a year. Bigadan intends to establish CO₂ capture across all its Danish biogas facilities, potentially increasing capacity to 200,000 tonnes annually by 2030.

Arjun was an early institutional investor in Danish biogas infrastructure in 2020 and acquired an initial 49.9% interest in Bigadan in 2021. Since then, it has worked alongside management to optimise feedstock supply and refine the business’s hedging strategy, underpinning the expansion of biomethane production capacity across the platform. Arjun has also supported the development of Bigadan’s carbon capture capabilities and increased its investment in 2025 to become the company’s majority owner.

Surinder Toor, Managing Partner at Arjun Infrastructure Partners, said:

“Bigadan demonstrates what active, long-term infrastructure ownership can achieve. We entered the Danish biogas market early because we recognised the essential role biomethane could play in the energy transition and the potential to build a broader, integrated circular energy platform.

“Since investing in Bigadan, we have worked alongside management to scale and strengthen the business, encouraging the adoption of new capabilities such as carbon capture. The permanent storage of Bigadan’s CO₂ beneath the North Sea is not a pilot project. It’s a fully operational, industrial-scale value chain, and evidence of the long-term, sustainable growth in the business we have delivered. We’re incredibly proud to have played an active role in helping Bigadan achieve this first-of-its-kind in Europe.”

Henrik Iversen, Chief Commercial Officer at Bigadan, said:

“Greensand marks a historic milestone for carbon capture and storage in Europe, and we are proud that Bigadan is contributing biogenic CO₂ to it. Seeing the full value chain in operation - from capture and transport to permanent storage - demonstrates what can be achieved when industry, policymakers and technology work together.”

About Arjun Infrastructure Partners

Arjun Infrastructure Partners is an independent asset manager focused on mid-market infrastructure investments. Founded in 2015, Arjun manages approximately €8.2 billion of capital on behalf of prominent institutional investors across the digital, renewables, transport and utilities sectors.

Arjun began investing in Danish biogas infrastructure in 2020 through its acquisition of Sustainable Bio Solutions, owner of the SBS Kliplev biogas plant. It acquired an initial 49.9% interest in Bigadan in 2021 before increasing its investment in 2025 to become the company’s majority owner.

About Bigadan

Bigadan is a Danish renewable energy platform with more than 40 years of experience developing, constructing and operating biogas facilities. The company converts organic waste, including manure and food and industrial by-products, into renewable biogas, biomethane and nutrient-rich biofertiliser.

Bigadan owns nine operational biogas facilities producing approximately 1.3 TWh of renewable energy annually and plans to increase production to more than 2 TWh by 2027. Its three operational CO₂ facilities in Kalundborg, Horsens and Herning can supply more than 56,000 tonnes of biogenic CO₂ annually for permanent storage or industrial use.

About Greensand

Greensand is the EU’s first full-scale CO₂ storage facility and forms part of a complete carbon capture and storage value chain. The project is led by INEOS Energy, alongside Harbour Energy and the Danish North Sea Fund, Nordsøfonden.

CO₂ is transported through a dedicated terminal at the Port of Esbjerg and shipped aboard Carbon Destroyer 1 to the Nini West reservoir, approximately 250 kilometres offshore in the Danish North Sea. Greensand has capacity to store up to 400,000 tonnes of CO₂ annually during its first commercial phase, with potential capacity of four to eight million tonnes annually.