Porthos

The Porthos project will capture CO₂ from industrial facilities in the Port of Rotterdam and transport it through a 30-kilometer onshore pipeline to a compressor station. From there, the CO₂ will be pressurized and sent via a 20-kilometer subsea pipeline to the repurposed P18-A platform, where it will be injected into depleted gas reservoirs located 3–4 kilometers beneath the North Sea seabed. The storage capacity is approximately 37 million tonnes in total, with injection rates of about 2.5 million tonnes per year over a 15-year period. Injection will take place in phases, beginning with free-flow into the reservoir, followed by gas-phase and eventually dense-phase injection as pressures increase. Construction began in 2024 after the final investment decision in late 2023, with operations expected to start in 2026. The onshore and offshore pipeline systems, compressor station, and platform are all being built with scalability in mind, allowing for future connections to other projects such as Aramis and the CO₂next terminal. The project includes continuous monitoring of wells, reservoirs, and infrastructure during the injection period, with oversight by the State Supervision of Mines to ensure safe and secure long-term storage.