02 June 2026

Lessons learned – Financing a first-of-its-kind project

A CCS project such as Porthos demonstrates that large-scale CO₂ transport and storage is not only a technical challenge, but just as much a challenge in terms of financing, risk sharing and public support. As the first large-scale CCS project in the Netherlands and the European Union, Porthos had to develop a business model without existing market standards, regulated tariffs or proven financing structures. It is precisely for this reason that the project has yielded many valuable insights for future energy and infrastructure projects — lessons that Porthos actively shares to further accelerate the development of the CCS energy transition.

Early certainty on funding builds confidence
One of the key lessons is that early clarity on funding is essential to build confidence in the market. During the international knowledge-sharing webinar with CCS professionals late last year, Dorus Bakker, Porthos’s financial director, explained how important the €102 million European CEF grant and the Dutch SDE++ scheme had been for the project. These schemes provided a necessary foundation for investors, customers and shareholders. Without public support, the project would simply have been unfinanceable in its early stages.

Furthermore, as this was a first-of-its-kind project, there were hardly any existing references or market models available. This made public support and guarantees all the more important in order to mitigate risks and facilitate private investment. In this regard, the government not only played a catalytic role, but also acted as a risk-taker in a market that is still very much under development. The government acted as a grant provider and – given that Porthos’s shareholders are state-owned entities – assumed part of the market, demand and development risk, thereby ensuring that private parties were willing to participate.

Flexible subsidy schemes and predictable tariffs
Porthos has also experienced how important it is for subsidy schemes to align with a project’s development phase. In the early stages, there are still many uncertainties regarding technology, planning and costs, whilst investors simultaneously require financial clarity. The safety net mechanism of the SDE++ scheme mitigates the uncertainty surrounding future CO₂ prices and helps projects navigate this vulnerable phase.

The chosen tariff model also proved to be a key success factor. Porthos deliberately opted for a conservative and predictable transport and storage tariff that could fall later, but could no longer rise – except through inflation adjustment. This gave customers sufficient certainty for their SDE++ applications and strengthened confidence in the business case.

At the same time, Porthos found itself facing a classic ‘chicken-and-egg’ situation. Customers needed a transmission tariff for their grant application, whilst Porthos, in turn, needed insight into future volumes in order to determine that tariff. Close cooperation between the government, customers and the project organisation within working groups proved essential to break this deadlock.

The long-term certainty offered by the SDE++ scheme also played a key role here. The fifteen-year subsidy period provided sufficient certainty regarding future revenue streams for both capture projects and the transport and storage infrastructure.

Investing in future CCS infrastructure
Finally, Porthos demonstrates that investing in future-proof infrastructure delivers societal added value. A conscious decision was made to build an onshore pipeline network with a capacity of 10 million tonnes of CO₂ per year, whilst current customers supply approximately 2.5 million tonnes. In doing so, Porthos not only supports the current project, but also creates scope for future CCS projects and the further development of a broader CO₂ infrastructure in North-West Europe.

The common thread running through the project is clear: successful first-of-a-kind climate projects require strong public-private partnerships, long-term policy certainty and a financing model in which risks, returns and societal value are carefully balanced.