CO2 Reduction Potential of the Chemical Industry through Carbon Capture and Utilisation (CCU)

In an exploratory scenario, the study “CO2 reduction potential of the chemical industry through CCU” investigates the greenhouse gas (GHG) reductions that can be achieved in the global chemical and derived material industries if the entire demand for embedded carbon is met solely and exclusively via CO2 instead of from fossil sources. Major simplifications are used to achieve transparency and comprehensibility of the issue. Methanol (CH3OH) is considered to cover the needs for hydrocarbons for chemicals and derived materials among the various chemical intermediates as a representative pathway for renewable carbon. It is a plausible scenario to assign methanol a central role in supplying the chemical industry of the future.

The examined CCU-based production route includes CO2 capture as a mix of direct air capture (DAC) and capture from different point sources, hydrogen supply and the hydrogenation reaction for methanol synthesis. The GHG emissions related to CCU-based methanol synthesis depend on the emissions of the renewable energy production. Emissions of CCU-based methanol could be 67 to 77% lower compared to emissions from releasing embedded carbon of fossil fuels, when using current energy supply based on photovoltaics. With improvements in renewable energy production, the reduction could increase to levels between 96 and 100%.

The annual global demand for carbon embedded in chemicals and derived materials could rise from 450 million tonnes of carbon (Mt C) today to 1,000 Mt C by 2050. Meeting this demand with CCU-based methanol would cause an immense demand of 29.1 PWh/year of renewable energy. Enormous efforts would have to be made to deploy sufficient renewable energy. If desert photovoltaic is used to produce the hydrogen, theoretically 1.3% of the Sahara area would be required to cover the entire demand.