Carbon capture and storage is the solution for greenhouse gases, based on net-zero policy goals

By Ian Palmer, PhD

CSS for enhanced oil recovery
CSS for enhanced oil recovery (illustration: I. Palmer)

Fossil fuel causes 75% of global greenhouse gas emissions (GHG). Carbon capture and storage (CCS) is an escape hatch, or an offset, to be used if there are “leftover” GHG emissions – to bring the total back to net-zero.

What is carbon capture and storage
Carbon capture and storage means collecting GHG (usually CO2, the dominant component) and burying it deep underground. “Bury” means to inject CO2 down a well where it’s contained by a non-leaking rock layer, and eventually merges chemically with the rock. The rock layer can be a depleted oilfield or a saline aquifer.

The process, called EOR for enhanced oil recovery, has been used by the oil and gas industry in the US for decades. CO2 is injected at one well to soften up the residual oil that is then produced from a second well along with some of the CO2.

Why CCS is a no-brainer
First, it will be a huge challenge for the world to make it close to true-zero GHG emissions by 2050 (the most common goal) because the world’s fossil energy economy and infrastructure are gigantic, worth USD 87 trillion.

Second, bp have predicted in their “Rapid” scenario that oil and gas will still be 36% of total global primary energy by 2050. CCS projects will be needed to offset the CO2 that comes from burning this 36%.

Third, CCS will also be needed for heavy industries that are difficult to decarbonise, such as cement and steel-making plants that produce significant CO2.

CO₂ storage estimates in North American oil and gas fields
CO₂ storage estimates in North American oil and gas fields (illustration: NETL, DOE)

CCS future for US
The US has plenty of storage capacity just in old oil and gas fields. US now emits 6,000 Mt/year of GHG and this entire amount could be stored each year for 23 years.

But new pipelines to transport GHG would have to be built or old gas pipelines retrofitted. While 45Q tax credits from the US government exist and will help – $50/ton of CO2 injected by CCS, or $35/ton if it’s used for EOR – cost remains a question and carbon-pricing would probably have to be mandated.

ExxonMobil is storing 9 Mt (million tonnes) of CO2 each year, equivalent to 11 million car exhausts each year. The company plans to invest USD 3 billion on 20 new CCS facilities – some to bury CO2 from other industries, such as cement or steel plants.

Occidental Petroleum are building a direct-air-capture wall of fans in West Texas that will suck in air and separate the CO2 for underground injection. They envisage a new business that will assist other paying customers to get rid of their CO2.

CCS future for Europe
According to Rystad Energy, power plants, transportation, industry, and buildings represent the larger portions of GHG. These could be covered by electrification, with partial or full use of batteries.

What could be fully covered by hydrogen is shipping, aviation, and industrial processing of chemicals and steel, totaling 7% of global GHG. By 2050 Rystad Energy predicts that 7% of the total CCS (8,000 Mt/year) would be CO2associated with hydrogen production.

Green hydrogen is produced by electrolysis of water. Blue hydrogen (H2) is created when methane, CH4, is broken into H2 and CO2. The chemical process is called ATR. The biproduct, CO2, would need to be buried by CCS.

Bp have plans for a large blue hydrogen plant at Teesside in the UK – to provide 20% of UK’s hydrogen needs by 2030. The goal of this first “hydrogen hub” is to decarbonise the nearby industrial area, as well as supply hydrogen to homes. BP will operate two CCS projects that would bury two Mt/year of CO2 from the production of blue hydrogen, equivalent to the emissions from heating a million UK homes.

Rystad Energy anticipates that 3 Gt/year of CO2 will need to be removed from the air by 2050, out of a total of about 47 Gt/year total GHG emitted in 2019. This 3 Gt/year will be shared by direct-air-capture and BECCS.

CCS future across the world
Currently, 65% of CCS occurs in the US, with 10% or so in each of Europe, Australia, and the Middle East.

On a worldwide basis, OGCI reported a CCS capacity from 715 sites in 18 countries that would supply projected CCS needs for 1300-2600 years.

CCS in 2020 stored only a paltry 40 Mt/year. Rystad Energy predicts it will need to be 8,000 Mt/year by 2050 – a total increase by 200 times. This would represent a 20% growth in CCS year-over-year. The numbers are staggering, but to make it happen a CCS industry would end up as big as the present-day oil and gas industry.

Ian Palmer, PhDA petroleum engineer and consultant, Ian Palmer, PhD has worked at Los Alamos, The Department of Energy, BP, and Higgs-Palmer Technologies. He is a contributor at Forbes.com and the author of The Shale Controversy.