Utilisation of CO₂

The focus of NEG8 Carbon is to capture CO₂ from the atmosphere (Direct Air Capture or DAC) and utilise it in decentralised applications. Ideally, we seek to capture carbon and use it in the same location to avoid the carbon penalty of moving the carbon. As summarised in another blog, “How do we Remove the 13%+ of Global Emissions Which Cannot be Tackled Using Traditional Methods“,  to achieve global net zero for ‘difficult’ CO₂ emissions in the long term, up to 10 billion tonnes a year needs to be captured from the atmosphere and utilised. This large scale usage will reduce the impact of climate change.

In this blog we look at;

1. Current uses of CO₂ in the world and their replacement by carbon captured from the air.

2.  Future uses of CO₂

3. Sequestration of CO₂

Current Usage of CO₂

We use approximately 230 million tonnes (Mt) of carbon dioxide (CO₂) annually. The largest consumer is the fertiliser industry where 130Mt of CO₂ is used followed by the oil and gas industry at 80Mt for Enhanced Oil Recovery (EOR). The remainder of 20Mt is used in the food and beverage industry, metal fabrication, cooling, fire suppression and for stimulating plant growth in greenhouses. CO₂ from the air can be substituted for about 100Mt annually of this usage.

We need action at Government policy level to encourage the use of recycled carbon in these applications

Future Uses of CO₂

The most promising areas of usage are;

– Building materials. 

CO₂ can be used in the production of building materials and has the potential to enhance the product quality and to sequester CO₂ for millennia. With a favourable regulatory environment and investment by industry and research partners, this usage could reach up to 1.4 billion tonnes (Gt) per annum by 2050.

– Enhanced Oil Recovery (EOR). 

Due to the fact that most oil wells don’t have a convenient source of CO₂, there is a significant potential to expand its usage with carbon from DAC thereby achieving net zero carbon emissions with this technology. While fossil fuels continue to be needed, CO₂ can be used for EOR at the same time sequestering large amounts of CO₂ for centuries. This usage could reach up to 1.8 Gt/year.

– CO₂ as a fuel.

Combining hydrogen with CO₂ can produce hydrocarbon fuels and replace fossil fuels for high energy applications e.g. shipping, heavy duty vehicles, aviation. For these fuels to be economic we need a cheap source of hydrogen. Ideally, regulators could mandate the use of off peak or surplus electricity for the production of hydrogen. This would allow us eliminate fossil sourced fuels and utilise up to 4.2 Gt CO₂/year.

– CO₂ as a new material

Carbon nanotubes and graphene are some of the latest man made materials which are currently used in specialised applications. The availability of large volumes of CO₂ allows for the possibility of using carbon fibres for industrial wiring and the widespread replacement of steel and concrete by carbon composites.

Sequestration of CO₂

There are many areas with mineral rich soils in the world that have the potential to hold much more carbon than at present. This is an area that grass-rich/forest-rich countries like Ireland need to explore with the soil scientists locally to investigate and realise the potential for this area of CO₂ sequestration. Worldwide, up to 1.9 Gt/year could be sequestered with additional benefits of enhanced agricultural yields.

Conclusion

We can do something about climate change and help lead the world in the area of carbon capture and usage. We need active policies for carbon capture and reuse/sequestration which encourages investment by industry and academia to achieve the targets set out above. The window to impact climate change is closing and we need action now. 

Sources used in this blog include

www.iea.org putting CO₂ to use

www.energypost.eu/10-carbon-capture-methods-compared-costs-scalability-permanence-cleanness

www.neonscience.org/observatory/observatory-blog/what-role-do-deep-soil-minerals-play-carbon-storage