Does CCS Offer Fossil Fuels a Real Lifeline?

With COP28 nearing, many in the oil industry keep repeating that emissions are the problem, not fossil fuels, and that the most "pragmatic" approach to climate change is therefore to capture as much carbon as possible rather than to focus on cutting oil and gas demand. Climate scientists agree that carbon capture and storage (CCS), direct air capture (DAC), afforestation-reforestation and similar technologies are indispensable. But their models clearly show that those only come as an addition to what should be the world's priority — massively phasing down fossil fuels.

Energy Intelligence's review of the main climate models shows that those targeting 1.5°C without phasing out fossil fuels assume around 9 billion tons per year of carbon capture and removal by 2050. This would complement 26 billion tons/yr achieved by a 72% drop in fossil fuels supply between now and midcentury — or minus 86% for coal, minus 67% for oil and minus 56% for gas.

COP28 Host's Ambitions

COP28 President-Designate and Head of Abu Dhabi National Oil Company Sultan al-Jaber is much more ambitious for carbon capture and removal. He said in a recent speech that the world could remove "up to 25 billion tons" of carbon emissions annually. Assuming carbon neutrality remains the goal, that would allow fossil fuels to fall by only 25% between now and 2050 if coal's market share was to remain constant, or for oil and gas to grow by 36% if coal was phased out, Energy Intelligence calculations show. The problem with a 25 billion ton/yr, or even a 9 billion ton/yr industry, is that it would be physically bigger than any existing industry and would need to be set up in just 25 years, which critics find unrealistic. The entire oil and gas sector, for example, yields around 7 billion tons/yr, coal 8 billion tons/yr and agriculture 9 billion tons/yr of produce.

To address residual emissions and the likely temperature overshoot, models use a combination of plain CCS to prevent additional emissions and carbon removal to reduce existing carbon concentration in the atmosphere. Bioenergy with CCS (BECCS), while based on the same processes as plain CCS, is a removal technology. So are DAC and nature-based solutions such as afforestation-reforestation.

Ambitious Scenarios

The most ambitious scenario in terms of removal is Shell's Sky 2050, with 0.4 billion tons/yr of DAC, 1.5 billion tons/yr of BECCS and 6.1 billion tons/yr of nature-based solutions. Those would involve some 700 million hectares of land per year, almost the size of Australia, for a mix of afforestation-reforestation, changed agricultural practices and wetland protection. Next are Equinor's Bridges, the International Renewable Energy Agency (Irena) 1.5 scenario and the Intergovernmental Panel on Climate Change's (IPCC) average of 1.5°C scenarios, each at around 4 billion tons/yr by 2050. While Irena gives little detail on technologies, Equinor and the IPCC roughly assume the same distribution between nature-based solutions, at just over 2 billion tons/yr, BECCS at around 1.5 billion tons/yr and DAC at half a billion tons/yr in 2050. By contrast, the International Energy Agency (IEA) excludes nature-based solutions from its net-zero scenario as an "explicit decision" not to rely on offsets from outside the energy sector to address energy emissions. The IEA's net-zero scenario incorporates 1.4 billion tons/yr of carbon removal, including around 1 billion tons/yr of BECCS and 0.4 billion tons/yr of DAC.

While most scenarios end in 2050, the IPCC and Shell provide predictions to 2100. Shell's Sky 2050 achieves negative emissions in 2060 and reaches minus 12 billion tons/yr in 2100. By that time, fossil fuels are projected to be almost phased out, at respectively minus 98%, 90% and 87% from today for coal, oil and gas. For that reason, CCS from fossil fuel emissions would fall to 1.4 billion tons/yr in 2100, down from a peak 5.1 billion tons/yr in 2050. CCS from hard-to-abate industries, notably cement production, which has limited decarbonization alternatives, would stabilize near 1 billion tons/yr around 2055. BECCS would reach 3.5 billion tons/yr, and DAC 5.4 billion tons/yr in 2100. Nature-based solutions would peak in 2060 at 6.7 billion tons/yr, and fall to 3.2 billion tons/yr in 2100.

The IPCC's 1.5°C scenarios equally predict the quasi-phaseout of coal and oil, but are less pessimistic for gas, which would still account for 10% of primary energy supply in 2100, down from a quarter today. This would involve more CCS, at 16 billion tons/yr, than the 11 billion tons/yr in Shell's scenario. Negative emissions would be achieved between 2050 and 2060 and reach minus 10 billion tons/yr in 2100, in line with Shell's 12 billion tons/yr.