Energy Saving Potential of CO2 Transportation Processes in Cold Climate Locations

Abstract

Carbon Capture and Sequestration (CCS) is a technology that can help reduce CO2 emissions and thereby mitigate global warming. The temperature of the available cooling medium effects many of the processes relevant to CCS and in particular, low ambient temperature helps reduce the power consumed by compression and liquefaction processes needed to prepare CO2 for transportation, e.g. in pipelines or tanker ships. The aim of this paper is to look at energy usage in different geographic locations and identify the benefits of preparing CO2 for transportation in a cold climate. The main finding is that the pipeline alternative consumes 10–15% more energy in the Middle East than in Northern Norway, and 25–30% more if the CO2 is liquefied. Lower temperature also offers an opportunity to simplify CO2 compressor design. The most efficient refrigerant for CO2 liquefaction is NH3 (R717), but CO2 (R744) is a practical alternative for cold climates.