Carbon capture keeps proving its critics right. What comes next?

Ketan Joshi
Published in
7 min readJun 7, 2021


The capability to capture carbon emissions created through the burning of fossil fuels has been of deep emotional and existential significance to fossil fuel industry executives, investors and defenders for many decades now. To them, it seems to fend off a public concern — climate action — while retaining the private benefit — the revenues that flow from digging up and burning fossil fuels.

It’s back in the spotlight, channelled now through the lens of using fossil fuels to produce hydrogen. But we have decades, now, of data about whether the technology has lived up to the promises of the past, and these ought to feed our views of today’s promised futures.

The history of promise

Currently, the total capacity to re-capture carbon before it’s released into the sky and oceans is 40 megatonnes of carbon dioxide per year. The vast majority of it is captured so it can be re-injected into oil reservoirs to aid the extraction of more fossil fuels; only a small minority is dedicated geological storage of that CO2. Over the latter half of the last century and well into the first quarter of this one, the world’s carbon emissions have risen dramatically:

It’s almost a cruel comparison, but if anything, it’s formatted in favour of CCS — the CO2 data should really be cumulative, because it accumulates in the atmosphere. Of course, the story is the same, for Australia:

Back in 2006, the Australian Coal Association suggested that by 2020, a ‘quarter’ of emissions from coal and gas could be captured. In 2020, 0.04 gigatonnes was captured, and approximately 20 gigatonnes were released. Pretty far from one quarter.

We can easily zoom down to the company level, too. As I’ve written previously, Exxon and Shell make a point of including the quantity of carbon they’ve captured in their emissions data. Equinor own a carbon capture plant too, at least, around 58% of one. The ‘waffle charts’ below show how much each company has captured, and the amount of carbon they have released without capturing it.

““ExxonMobil has cumulatively captured more carbon dioxide than any other company, accounting for more than 40% of all carbon dioxide captured in the world” — that’s 40% of nothing.

Exxon comfortably leads the way, and it’s reflected in wider data from the Global CCS Institute which shows America comfortably holds the bulk of the world’s operational carbon capture capacity.

It is surprisingly difficult to visualise exactly how minor the contribution of carbon capture has been. But for these companies, only a tiny fraction of their emissions released are captured by CCS technologies. The story is far worse for the world — the total fossil emissions released over the decades have added up, and the cumulative amount of carbon captured is measly.

It is surprising and telling how rare it is to see metrics like this. They don’t crop up in articles about new promises of CCS; nor do they crop up in the discourse of fossil fuel companies. But it matters, quite a lot, that for a very long time CCS has been promised, but it has delivered only in the tiniest and slowest of increments.

The IEA’s predictions of carbon capture

Recently, the International Energy Agency (IEA) released a scenario that genuinely shook things up. It was a scenario that modelled what’s required to reach net zero emissions by 2050 — that is, for the world to align with 1.5 degrees celsius of global heating, relative to pre-industrial levels.

As we know from many previous scenarios, it’s a big deal. It means stopping the exploration of new oil and gas fields, cancelling all new coal mines, shutting down coal plants before 2030 in advanced economies and around the world by 2040. Much of this was already known, but for it to come from the IEA was stunning.

But buried in the details, some interesting factors emerge. To replace the energy supplied by fossil fuels, a huge build-out of wind and solar is required, alongside the electrification of things like cars, homes and industry to run on those technologies. The change in wind and solar looks like this:

That’s a relatively steep acceleration of the amount of new electricity required from wind and solar, in the IEA’s scenario. But if you look at this in terms of how many new gigawatt hours are added each year, it isn’t quite as steep as it looks, because wind and solar growth has been accelerating over the past decade. That is to say, each year sees more new stuff added than the last, and if this pathway is to be followed, that trend has to keep going:

Plenty of serious effort is required to accelerate the provision of clean power from wind and solar, but there’s a strong precedent for acceleration in the historical records of how they have been deployed. That means the technological, social, and political factors are all relatively well understood, and mostly just need to be scaled up.

But the IEA’s report also leans surprisingly heavily on carbon capture and storage, which means the fossil fuel industry lingers noticeably. The modelling allows for 663 terawatt hours of coal with CCS, and 669 TWh of gas with CCS, in 2050 (7% and 11% of 2020 levels respectively). And when it comes to steep inclines, CCS really takes the cake:

The assumptions of the quantity of CCS deployed in this model are very, very far removed from the historical rates of additions of new CCS. This isn’t a continuation and expansion of proven existing trends — it’s the creation of an entirely new trend, and therefore, a problematic pathway. If we look at the change each year, just as we did for renewables, this becomes incredibly clear.

The IEA report assumes around a 3–4x scale up in the annual addition of renewables, by 2030, compared to 2020. But it assumes a 59x scale up in the annual additions of CCS capture capacity, by 2030. How is this going to happen?

In fact, the Global CCS Institute’s 2020 report includes a list of planned carbon capture projects, along with their potential carbon capture amounts. We can compare that very easily to the IEA’s net zero scenario, for this coming decade. It’s not good.

Of course, the past doesn’t decide the future — you could’ve made a similarly skeptical argument about renewable energy back in 2010, or 2000, and many did. Perhaps what’s really needed is just more political and policy effort to realise the quantities of carbon capture and storage, because every amount of carbon avoided helps?

Well, that’s an overly simplistic view. An excellent piece of recent research dug into the many reasons why proposed CCS projects frequently fall over — comfortably, the vast majority of projects. They’re expensive, the technology still isn’t ready for the prime time, and there’s no real financial rewards for doing this, even when you use the captured carbon to unlock more fossil fuels. Government regulation of carbon would help, but fossil fuels companies spend their effort killing this off. And a recent IEA report shows that fossil fuel companies spend very, very little on CCS, compared to their total capital expenditure:

Renewable energy has its own upwards struggle, but we know a lot about that, and we know how it is changing. There are blanks yet to be filled, such as how to manage the complex social and community challenges of building vast quantities of wind and solar in land-limited countries, or how to manage the critical sources to build electric vehicles. The gap between what’s needed and what’s currently in the pipeline exists, and needs to be addressed — but it’s possible to address it, and we know that putting the effort in wields clear results.

But for CCS, very little has changed. It remains functional only as a promise; featuring heavily in the plans of fossil fuel companies and carving out a smaller and smaller space within visions of the future that they’re willing to say out loud. Not only is the gap between promise and reality much, much bigger compared to renewables, there is no evidence that its corporate proponents are much inclined to put effort into filling that gap, and plenty of evidence that they’ll continue stalling for as long as they can.



Ketan Joshi

Anecdata analysis, research, writing, caffeine. Science, tech and data communications professional in Sydney.