The great potential of Carbon Capture & Storage

Carbon emissions reductions

This year, British home secretary Amber Rudd committed the UK to the ‘fifth carbon budget’, which binds the nation to a maximum CO₂ output between the years 2028-2032 of 1,725 MtCO₂e. Currently, it is thought by many that the UK will not meet this target without substantial changes to energy policy. CCS has a potential to account for 17% of necessary the nations carbon emissions reductions, and so would offer great support for the British energy industry as it may mean that there wouldn’t be a need for such a rapid switch to renewable energies which would inevitably be very costly.

Storage potential

There appears to be a vast storage potential for CO₂ within the Earth, but due to the numerous types of geological formations, the planet’s potential is difficult to estimate. Scientist Udayan Singh reports on IPCC suggestions that there may be the opportunity to store 2000Gt of CO₂ within the planets formations. Further investigations into this reveal that between 675-900 Gt of CO₂ could be stored into oil and gas fields, 1000-10,000 Gt of CO_2­ may be contained in saline formations and between 3-200 Gt of CO­₂ within coal beds. Udayan Singh importantly points out that in 2010, annual global CO₂ emissions were less than 34 Gt of CO₂, thus clearly demonstrating that the world can take confidence in this environmental policy. In addition it is also important to note that as our fossil fuel consumption increases, more space in geological formations for CO₂ storage will become readily available.

Key carbon storage examples:  UK & India case studies

In terms of the UK’s personal environmental policy, Jon Gibbins and Hannah Chalmers predict the UK offshore CO₂ storage potential to be at least 20 Gt of CO₂. This type of formation alone could store the UK’s CO₂ emissions for 40 years!

Fig. 1 - A geological map of India, showing the presence of basaltic rocks
as well as highlighting regions of good, limited or fair storage potential
https://hub.globalccsinstitute.com/publications/regional-assessment-potential-co2-storage-indian-subcontinent/22-potential-geological

Researchers Udayan Singh also reveals information regarding the storage potential of India (the world’s third largest CO₂ producer) and combined their research with McGrail et al’s laboratory experiments to conclude that India alone has an incredible potential for CO₂ storage within onshore and offshore saline aquifers (360 Gt) and within Basaltic rock settings (200 Gt). McGrail et al’s tests revealed that the basalts within the region showed fast chemical reactions with CO₂-saturated water, enabling it to produce stable carbonate minerals. When analysing fig 1, one can realise that due to the vast quantities of basaltic rock within India (formed as a result of the Deccan Traps eruptions which produced material that covers 500,000km² of India’s Western provinces), India’s storage potential within this type of geological formation, and future potential after further scientific research into this field is immense.

Another advantage which would result from storing CO₂ within depleted oil and gas fields is that it will allow for the  recovery of further oil and gas that was not initially recovered for a variety of reasons, for example because it was not initially economically viable. CO₂ also has many industrial purposes, and is used in pharmaceutical, fertilizer and beverage carbonation industries (Udayan Singh).

These methods provide further advantages, as pumping CO₂ into oil fields can also help to retrieve more fuels that were not recovered during initial oil exploration. This is due to the fact that CO₂  injection reduces the viscosity of oil, thus improving the ability of oil  to flow up boreholes to the surface.Whilst in basalt formations, CO₂ reacts with the basalt to form carbonate minerals, further adding to the stability of the formation.

Economic incentives

An interesting economic incentive to carbon capturing is the emission trading mechanism, which limits a country to a maximum volume of CO₂ that can be emitted. However if a country to reduce its emissions below the maximum amount, they would be able to use the CO₂ as a commodity which they could then use in trading and thus generate profits from. This offers yet another advantage for Less Economically Developed Countries, who may not otherwise prioritise emission reductions due to their respective financial situations.

Furthermore, the UK government reports that should CCS be fully implemented into power plants that produce electricity for domestic use, energy prices for citizens would decrease by up to £0.02 per Kilowatt hour (Kwh) by 2030 (fig.2). Correlating this to the whole UK population would show significant energy savings nationally. 

Fig. 2 - A chart expressing future energy savings (in pence per Kwh) per year
with CCS implementation.
https://www.tuc.org.uk/sites/default/files/carboncapturebenefits.pdf

Therefore one can conclude by realising that there is a great potential for CCS, with positive practical and economic aspects, what now needs to be decided is whether these positives outweigh negative issues, which will be talked about in the next blog post.