Is carbon removal a realistic climate solution?

There is no golden bullet to 'stop climate change' however, in transitioning to a low carbon economy Carbon Capture is needed to support decarbonisations in many industries. This article breaks down Carbon Capture & Storage into its many forms, and explores the viability and effectiveness of these solutions.

Essential for net-zero

Using alternative energy sources, and implementing decarbonisation strategies in many industries is very possible, other industries like shipping are much less straightforward. Carbon capture then presents itself as a promising technology to supplement and support other mitigation technologies particularly during this transition period.

 “The deployment of carbon dioxide removals to counterbalance hard-to-abate residual emissions is unavoidable if net zero…emissions are to be achieved.”

UN panell on Climate Change (IPCC, 2022).

So, what exactly is carbon capture, and how does it work?

The first thing to know is carbon capture comes in many forms, and its impact varies depending on the integrity of individual efforts. The following diagram breaks down carbon capture into two main components: Carbon Dioxide Removal (CDR) and Carbon Capture and Storage (CCS).

Image credits above: biodGRADable.com

Carbon Capture vs Carbon Removal

Carbon capture and storage (CCS) refers to the collecting of CO2 directly from the source, such as factories, before it enters the atmosphere. Carbon dioxide removal (CDR), on the other hand, seeks to remove CO2 already in the atmosphere.

Direct air capture (DAC)

DAC or Direct Air Capture is the removal of CO2 already in the atmosphere through large industrial equiptment (ideally powered by renewables). Think of this like an atificial tree, only it can store carbon indefinitely, wheras trees release CO2 when they die. Full article: What is direct air capture and how does it work?

Nature based solutions to CDR

Some solutions such as the one by Charm Industrial, utilise plants carbon capture potential and then store the carbon underground where it stays indefinitely. While others, (BEECS) re-use the carbon for energy.

Bio-energy carbon capture and storage (BECCS) is a more nature-based solution. With BECCS, CO2 is captured by trees, and this biomass is then used in industry or fuels to produce energy. Esentially, this is net-zero in theory. It captures as much as it emits (if managed carefully) meaning you can have 'zero impact' energy production. Carbon emitted via energy production can then be captured and stored at souce, making it net negative. The main consideration here is that this method is very land intensive.

Where is captured carbon stored?

Once captured, CO2 is generally stored in underground reservoirs. While this is often the case with carbon capture usage and storage (CCUS), carbon capture and utilisation (CCU) looks to use some of the captured CO2 in industrial processes such as fertiliser production (think 'recycling carbon').

Is Carbon Capture Greenwashing?

Companies can use Carbon Capture to accomplish 'greenwashing' if it is used as a scapegoat to expand harmful operations and neglect environmental footprint. CO2 capture is not inherently 'greenwashing', but we must consider how this tool is used. Companies should source renewable energy and reduce their emissions where possible, using DAC to counter-balance areas that cannot be reduced in order to acheive net-zero.

At the moment, polluters such as oil companies are not required to use carbon capture technology, but there is growing pressure to get this written into law and force those producing vast quantities of CO2 to address their planetary impact, and ultimately support this transition to a low-carbon economy. CCS would allow industries to continue using fossil fuels while there is still availability, enabling them to, in a way, continue with ‘business as usual’ with this mitigation technology used alongside. CCS is therefore generally the preferred option for such companies because they do not have to abandon their current business model and can still rake in those huge profits.

There is, however, lots of controversy surrounding a certain aspect of this topic: enhanced oil recovery, a process some would like to see included as ‘CCS’, but others not. Enhanced oil recovery works by injecting and storing CO2 into the earth, forcing oil up towards the pump where it can be collected. The issue with this is while some explain that captured carbon can be used in this process, later storing it way underground, this oil is extracted with the intent to burn it and use it as an energy source. This end goal, then, seems to make the carbon-capturing aspect futile when finite fossil fuels are still used and not alternative energy sources. The question here is if we are using CCS, shouldn’t we move away from unsustainable fuels entirely?

A recent IPCC report argues that some form of carbon capture will be needed if we are to stay below an ‘increase of 2 degrees Celsius by 2100’. Therefore, demonstrates the great potential here, and how it will most likely play a role in future technology and how we adapt to the challenges presented by climate change. There is, though, doubt about how CCS can best be carried out and in what applications, with concerns that more research and developments are needed before it can be properly upscaled.

Article by Heidi Surfleet

Diagram - Max Kennan on Canva

References: https://www.youtube.com/watch?v=Tra0yeTsm1k