Capturing, storing, and recycling carbon: Iceland's CCUS initiatives

Why carbon capture?

While clean energy generation should remain at the ‘top of the pile’ for combatting climate change, capturing, storing, and, in some cases, recycling carbon dioxide will also play a vital role in softening the damage already incurred, and mitigating that which is anticipated, before reaching net-zero.¹ CCUS is invaluable for offsetting emissions that are difficult to avoid, since even building the assets to generate green energy – such as wind turbines, which use steel – inevitably leads to emissions.²

According to the latest IPCC report, an aggressive reduction of emissions is required across all sectors in order to halve global emissions by 2030 and limit global warming to 1.5°C.³ Attaining these targets without the assistance of CCUS will be very difficult, to say the least. To illustrate the magnitude of this task, 8 gtpy of CO₂ needs to be captured by 2050 to reach net-zero emissions by that same year, while current global capture capacity sits at 0.04 gtpy.⁴ How we deal with the carbon we are emitting, then, is another axis by which the climate crisis can be addressed, with Iceland providing an effective example of how CO₂ can be managed.

Direct air capture in Iceland

Climeworks is a Swiss direct air capture company that procures CO₂ via the world’s first large scale CO₂ removal plant, Orca, in south-western Iceland. The company offers a DNV certified carbon capturing service to companies who are looking to reduce their emissions. The Orca plant itself consists of eight collector containers, each with a gathering capacity of 500 tpy; capturing CO₂ automatically through the use of fans, a solid filter, and heat. The energy to run the Orca plant is supplied by the adjacent ON Power owned Hellisheiði geothermal power plant.⁵

Climeworks' CO₂ removal plant, Orca.

Plants like Orca are 1000 times more efficient at removing CO₂ than a forest of an equivalent size. Trees covering the same 0.42 acres would only be able to remove 4.62 tpy compared to the 4000 tpy extracted by the Orca plant. Of course, 4000 tpy is still very little when compared to the aforementioned gigatonne figures that need to be achieved by 2050. However, as a testament to the scalability of this technology, Climeworks is currently building a larger plant, Mammoth, that will be able to capture 36 000 tpy once built.⁶ All that is needed for these plants is a renewable source of energy to run the plant (Iceland has geothermal in abundance), and a means to store the gas once it has been captured. The storage part is performed by Carbfix, who is storing the captured CO₂ in mineral formations beneath the ground for over 10 000 years, which is a neat little segue onto the next port-of-call.

Interesting uses for Iceland’s geology in carbon storage

Carbfix is a prime example of how Icelandic companies have harnessed the island’s unique geology and turned it into an asset for CO₂ storage. Located atop of the mid-Atlantic ridge – a growing rift between the Eurasian and North American tectonic plates – Iceland is a beacon of volcanism and geothermal resources. Consequently, Iceland has extensive basalt formations – a reactive, permeable, and porous igneous rock that forms through the rapid cooling of low-viscosity lava. Basalt is rich in iron, calcium, and magnesium, which react with carbonated water to create stable carbonate minerals like calcite. In essence, it turns CO₂ into stone.⁷

Comparison of regular basalt (left) and basalt once reacted with CO₂, the white spots are carbonate minerals (right).

Carbfix has accelerated this natural process to just two years; sequestering the CO₂ from companies like Climeworks and dissolving it in water through a machine akin to an enlarged sodastream machine, before depositing it in basalts underground. At the Hellisheiði power plant, they essentially hitch a ride with the geothermal water being extracted from the resource, carbonate it and then pump it back underground through the existing boreholes. This way the water is continuously recycled and carbon emissions are dealt with at the same time, an example of how efficient Iceland is with its geothermal resources (a topic which will be covered in greater depth in the Winter issue of Energy Global).

ON Power's Hellisheidi geothermal powerplant.

The global storage potential, theoretically, surpasses the emissions from burning all the remaining fossil fuels on Earth. Current estimates suggest Europe has a 4 billion t storage capacity, with the US having as much as 7 500 billion t.⁸ Moreover, recent studies reveal that this method could actually work with sea water, a significant advantage considering much of the world’s basalt lies beneath the ocean. Researchers are even exploring the possibility of applying this method to other types of rock, and so there may be even more space than originally calculated. Carbfix is currently working on the Coda Terminal project, which is a port of sorts, wherein other nations or companies can transport their CO₂ for Carbfix to sequester and store in Icelandic basalts.⁹ The potential in this method is huge: carbon can be extracted from anywhere in the world and securely stored in basalts (or perhaps other rocks) either in Iceland or elsewhere.

 

One of Carbfix's pods that shelters workers monitoring the pumps from Iceland's harsh elements. 

 

Recycling CO2

Another interesting feat in Iceland is Carbon Recycling International’s (CRI) endeavours to recycle CO₂ into methanol. A leitmotif when discussing the climate crisis is to view CO₂ as the cause of all our ills and a harmful greenhouse gas that heats up the atmosphere. CRI is founded on the premise that carbon is not a waste gas, but a useful tool to create methanol.

The company does this by combining CO₂ with hydrogen, sourced either from water electrolysis (making e-methanol), or as a by-product of industrial processes (low carbon methanol). Methanol is a versatile substance used in glue, plastics, building materials, paints, and solvents, though most importantly, it makes cleaner fuels and can easily be blended with gasoline. Methanol is being considered as an alternative in the shipping industry due to its ease of storage (it is liquid at room temperature) and lower emissions. The potential usage for methanol is huge, as it cuts CO₂ emissions by 95%, with its projected usage at 500 million t by 2050.¹⁰

The company’s George Olah Renewable Methanol Park, uses flue gas emissions from the nearby Svartengi geothermal Resource Park – owned by HS Orka – to create methanol. This is another example of how every last drop of geothermal resource can be utilised in Iceland, as even the natural emissions of CO₂ are used in other exploits. Here CRI is able to recycle roughly 5500 tpy of CO2 and create 4000 tpy of methanol.

Elsewhere, the latest plant running on this technology is recycling around 160 000 tpy of CO₂ into methanol. CRI has also managed to produce methanol for residual steel gas in the company’s FReSMe project in Sweden, which is particularly important relating back to the issue of steel being used to create wind turbines.¹¹ Carbon recycling is scalable, and valuable to the green transition through its ability to deal with unavoidable emissions, and create cleaner fuels in the process.

 

Conclusion

These three examples illustrate how a change in the treatment of carbon can help combat climate change beyond the scope of merely switching to clean energy. The reality is that emissions are unavoidable in the transition to net-zero; the damage being done and the damage that will be done needs to be addressed, and these technologies are a good way to do it. While there is a lot of work to do, with numbers still being far off the gigatonne level required by 2050, the growth in this industry is sure to happen. CCUS technologies function as a supplement to the green transition, as showcased by these three companies in Iceland.

 

Article by Théodore Reed-Martin, Editorial Assistant for Energy Global and LNG Industry at Palladian Publications Ltd.

 

References:

1. IEA, ‘Why carbon capture technologies are important’, https://www.iea.org/reports/the-role-of-ccus-in-low-carbon-power-systems/why-carbon-capture-technologies-are-important
2. Orsted, ‘What is the carbon footprint of offshore wind?’, https://orsted.com/en/insights/the-fact-file/what-is-the-carbon-footprint-of-offshore-wind
3. IPCC, ‘The evidence is clear: the time for action is now. We can halve emissions by 2023’, https://www.ipcc.ch/2022/04/04/ipcc-ar6-wgiii-pressrelease/.
4. IRENA, ‘Carbon Capture’, https://www.irena.org/Energy-Transition/Technology/Carbon-Capture#:~:text=Reaching%20net%2Dzero%20by%202050,current%20rate%20of%200.04%20Gtpa
5. Climeworks, ‘Orka’, https://climeworks.com/plant-orca
6. Climeworks, 'Mammoth: Our newest facility',https://climeworks.com/plant-mammoth
7. Carbfix, ‘How Carbfix works’, https://www.carbfix.com/how-it-works
8. Carbfix, ‘Where does it work?’, https://www.carbfix.com/atlas.
9. Carbfix, 'Coda Terminal', https://www.carbfix.com/codaterminal 
10. Methanol Institute, 'Renewable methanol', https://www.methanol.org/renewable/#:~:text=Compared%20to%20conventional%20fuels%2C%20renewable,oxide%20and%20particulate%20matter%20emissions
11. Carbon Recycling International, 'Our projects', https://www.carbonrecycling.is/projects

Read the article online at: https://www.energyglobal.com/other-renewables/08112023/capturing-storing-and-recycling-carbon-icelands-emission-reducing-initiatives/