The Port of Rotterdam CO2 transport hub and offshore storage (Porthos) project is a carbon capture utilisation and storage (CCUS) project near the port Rotterdam in the Netherlands. The project aims to transport and store CO2 produced by refineries, chemical- and hydrogen plants into empty gas fields in the North Sea. The CO2 will be captured by various companies, supplying their CO2 to the Porthos pipeline that will run through the Rotterdam port area. The CO2 will then be pressurised in a compressor station and transported through an offshore pipeline, before getting pumped into an empty gas field situated 20 km off the coast and more than 3 km beneath the North Sea. As soon as the investment decision has been taken, the construction of the infrastructure will start. It is expected that the system will be operational by 2024. The Porthos CCUS project has been recognised by the European Union as a Project of Common Interest and will be capable of storing approximately 2.5 million tonnes (Mt) of CO2 a year.