CO2: a solution to the climate crisis (provided it's the green and leafy kind)

Carbon dioxide (CO2) has gotten a bad reputation over the past three decades for being the main cause of global warming. And rightly so, as excessive emissions have triggered a global environmental crisis. However, we must revisit our preconceptions of CO2 and instead focus on the positive potential in utilizing biogenic CO2 to reach ambitious climate targets.

Biogenic CO2 originates with organic matter and is part of the natural carbon cycle where plants absorb CO2 through photosynthesis. Later, those plants will decompose or be burnt, releasing the CO2 into the atmosphere from where it is re-absorbed by new plants – thus creating a circular process.

While CO2 is the same molecule no matter where it comes from, the difference between it originating in the living world or from fossil fuels is substantial. Carbon from fossil fuels has been trapped for millions of years, and when it is released, it increases the CO2 concentration in the atmosphere. This is not the case for biogenic CO2, since the CO2 released is equivalent to what the organic matter in question has previously absorbed.

How can biogenic CO2 be used to solve the climate crisis? By combining it with green hydrogen, we can produce electro-fuels (e-fuels) such as e-methanol. And making hydrogen is not complicated – it’s a process that has been known for centuries. You may even have done it yourself in high-school chemistry class. An electrolyzer powered by renewable energy will split water, H2O molecules, into hydrogen, H2, and oxygen, O2. The hydrogen can then be used directly as an energy source or as a base for further processing.

Until recently, this couldn’t be done at a large scale because electricity wasn’t cheap nor green, and electrolysis requires a lot of energy. Thanks to the rapid build-out of renewable energy sources like wind and solar, we can now produce large quantities of green hydrogen. Green hydrogen is a burgeoning industry that will revolutionize the energy system.

One remarkable example is the global logistics company Maersk, which will use green methanol to operate a fleet of more than 20 container vessels, a prospect unthinkable not long ago. It was unthinkable because marine shipping is part of “hard-to-abate” industries. These also include sectors like aviation, cement, steel, and chemicals, which are responsible for a large share of global emissions. They are hard-to-abate because they cannot be directly electrified, as they rely on carbon and fossil fuels as integral parts of their energy consumption. Their emissions are deeply intertwined with the fabric of their operations, which until now has made decarbonization difficult.

Biogenic CO2 offers a solution in the pursuit of reducing fossil carbon emissions, because when we use it as an ingredient in e-fuels, such as e-methanol, we have a virtually carbon-neutral fuel for shipping or aviation. It might sound like science fiction, but as the Maersk example demonstrates the transformation is happening now. It is only one of the large companies stepping forward to show how to significantly decarbonize some of the heaviest emitters on the planet. Volvo has committed to using green steel in the frame of its heavy-duty electric trucks, and Apple has bought the first commercial-grade aluminum made with carbon-free smelting technology.

Carbon used for e-fuels should be based primarily on biogenic CO2, while fossil CO2 should be kept underground. It is important that it is not the other way around because storing biogenic CO2 will reduce the availability of a key component of e-fuels, which will drive up prices and slow down the decarbonization of hard-to-abate sectors.

Due to its pivotal role in the production of e-fuels, CO2 will soon become a tradeable commodity. And that is good. It will promote the realization of large-scale carbon capture projects and allow for utilizing biogenic CO2 and storing of fossil CO2 underground.

Regulators worldwide must, however, stay alert to the possible consequences of changing CO2 from waste to a commodity. Excessive biomass growth for the sole purpose of processing it into e-fuels must be carefully regulated to avoid deforestation and jeopardizing vital agricultural activities. In Europe, regulators have quickly spotted this problem, and regulatory bodies elsewhere should take a leaf out of their book, keeping a close eye on those trying to work around these restrictions.

To kickstart such a large-scale market, the industry actors require a certain degree of investment predictability. Regulators must step forward and provide the framework that supports all the multiple ways of CO2 transportation. The industry will rely on a network of pipelines, rail, ships and trucks depending on the location of the CO2 source and the usage of the technology.

The establishment of CO2 infrastructure should go hand in hand with hydrogen infrastructure and the deployment of renewable energy. The climate benefits from using CO2 in green fuels depend heavily on the combination of biogenic CO2 and hydrogen produced by renewable energy. The roll-out of these technologies will accelerate if the infrastructures are built in parallel.

While CO2 is the primary cause of climate change, it is time to shift our perspective and recognize the potential of biogenic CO2 as a major part of the solution in decarbonizing hard-to-abate industries and significantly reducing global emissions. Through technological innovations, collaborative alliances and thoughtful regulatory actions, we can usher in a new era of sustainability, where CO2 becomes an integral part of our journey toward a greener future.