Net Zero needs carbon capture
The point of Carbon Capture and Storage (CCS) is to stop fossil fuel use from causing global warming. Credit: Getty Images

Expert Comment: It is remarkable how much we agree. COP28 and the transition from fossil fuels

So, COP28 has just called for “transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner, accelerating action in this critical decade, so as to achieve net zero by 2050 in keeping with the science”. Is this the moment that the world finally decided to hit the brakes, even if ever so gently, on fossil-fuelled global warming? 

By Professor Myles Allen, professor of Geosystem Science. 

The last COP I attended in this region was COP18, in Doha, 2012. There, I was talking about some recent papers claiming that 50-80% reductions would not be enough, and that to stop global warming, carbon dioxide emissions would need to be reduced to net zero. A very experienced negotiator asked me quizzically if this research had been peer-reviewed (it had: ours was one of half-a-dozen papers that appeared in 2009 making much the same point), and then saying “ah yes, but it has not been assessed by IPCC”, in a relieved note-to-self voice of someone who did not need to worry about it. 

Ten COPs later, and the much-criticised UAE Presidency has pulled this off, in the first ten seconds of the final plenary session. Given fossil fuels were only mentioned in a COP decision text for the first time two years ago, and everyone seemed ready to write COP28 off just 24 hours ago, you have to hand it to them. 

Of course, it leaves questions unanswered. Does “energy systems” include transport (particularly relevant as I sit in Dubai airport)? What is “net zero” actually referring to (emissions, presumably, but which ones)? But “in keeping with the science” of “1.5°C pathways” doesn’t leave a whole lot of wriggle room.  

What ultimately matters, as the COP President Sultan Al Jaber likes to remind everyone, is not COP declarations and pledges, but what governments (and, of course, companies, universities and all the rest of us) actually do.

Does this text leave the door open to a future in which we just carry on using fossil fuels and reinject the carbon dioxide they generate back into the earth’s crust?

On this, many will be relieved the text prioritises “transitioning away from fossil fuels”, but will also be worried that further down it talks of “abatement and removal technologies such as carbon capture and utilisation and storage”. Does this text leave the door open to a future in which we just carry on using fossil fuels and reinject the carbon dioxide they generate back into the earth’s crust? 

There has been a heated debate about carbon capture and storage (CCS -- the “utilisation” is a bit of a side-show – what really matters for climate is where the carbon dioxide ends up) and "abated" fossil fuels at COP28. Should we be calling for “phase out of fossil fuels” or (Sultan Al Jaber’s preferred wording), “phase out of fossil fuel emissions”? But what is remarkable is how much everyone agrees, including within our own delegation: no-one could accuse Oxford University of stifling robust arguments and a broad range of views!'  

What is remarkable is how much everyone agrees

IPCC and IEA 1.5C scenarios consistently indicate what should be obvious to everyone anyway. We will generate more CO2 from burning fossil fuels than we can afford to dump in the atmosphere, so we need to scale up safe and permanent CO2 disposal which, right now, means CCS and, later on, direct air capture with CCS (despite the UK government’s enthusiasm for Drax, I'm personally unconvinced that bioenergy with CCS will ever play a huge role because of the true cost of land).  

So, as a matter of topology, not any model, we will still be using fossil fuels, fully abated, meaning 100% capture or recapture and permanent disposal of all the CO2 they generate, at the time we achieve durable net zero emissions. The only argument is how much.  

We will still be using fossil fuels, fully abated...at the time we achieve durable net zero emissions. The only argument is how much

The 1.5°C scenarios indicate around 10-30% of current usage at the date of net zero: coal almost entirely phased out, and roughly half current oil and gas consumption, all compensated for, or “fully abated”, with CCS at source or carbon dioxide recapture from the atmosphere. That is a vast and global carbon dioxide disposal industry, 100 to 300 times larger than the 40 million tonnes of carbon dioxide that we currently dispose of every year. So, we need to scale up CCS by at least two orders of magnitude – far more, in percentage terms, that we need to scale up many other low-carbon technologies. Claims that we can solve the problem without CCS risk discouraging this essential investment.  

That said, I understand that people are concerned CCS might be used by the fossil fuel industry to compete with renewables for investment and subsidies. It should not. They serve different purposes. The point of CCS is to stop fossil fuel use from causing global warming. The point of renewables is to deliver our energy needs in a world where fossil energy is scarce and expensive because we need to get rid of the carbon dioxide it generates. 

I understand that people are concerned CCS might be used by the fossil fuel industry to compete with renewables for investment and subsidies. It should not. They serve different purposes

Safe carbon dioxide disposal should just be a requirement of the sale or use of fossil fuels. Of course, that will make them more expensive, encouraging people to use them more efficiently and switch to renewables.

But as governments at COP28 have recognised, whatever happens now, we need to fix fossil fuels before we phase them out.