Steady-state optimisation of CCS pipeline networks for cases with multiple emission sources and injection sites: South-east Queensland case study

Abstract

A significant cost for carbon capture and storage (CCS) can be associated with transporting the captured carbon dioxide (CO2) to injection sites. It may be possible to reduce these costs by matching the CO2 sources and sinks through an appropriate pipeline network. A model for optimising CCS pipeline networks, including multiple emission sources, capture plants and injection locations, is under development. The optimisation is based on minimising the cost of the network using a genetic algorithm. The “total CCS network cost” includes the costs of building, operating and abandoning the capture plants, pipeline network and injection sites. As a case study, the optimisation model is used to design a CCS network for the emission sources in the south-eastern Queensland region. Different injection locations are considered. The optimal network is one in which all of the captured CO2 is transported via a branching network and stored at an injection location close to the emission sources. The pipeline and compression costs for the optimal network are A$18 per tonne of CO2 avoided, or approximately US$15 per tonne of CO2 avoided. These costs are 9% less than the pipeline and compression costs for a network that follows existing gas pipeline routes. The total CCS network cost was A$78 (US$66) per tonne of CO2 avoided.