Industrial Scale Air Purification – Finally!
If you have been following us for some time now, you would know that the environment and climate change are topics that are closest to our hearts. If you haven’t been following us, do check out local solutions to better air quality and geoengineering among others.
In early September, Iceland officially inaugurated the Orca plant around 25 miles from the nation’s capital, Reykjavik. Made by the collaboration of a Swiss company Climeworks AG and Icelandic company Carbfix, the Orca plant captures carbon dioxide (CO2) from the air by a method called Direct Air Capture (DAC) and converts it into rocks thereby reducing the carbon dioxide in the atmosphere.
Direct Air Capture (DAC) works on the principle of trapping the CO2 in the air using a chemical/filter known as an adsorbent. On exposure to heat, this trap releases all the CO2 which can then be collected and used for any other processes. The inspiration for this process partially came from the working of plants & trees that absorb CO2 and plug them into the soil. In the case of the Orca plant, multiple fans have been installed on 8 shipping container-sized boxes to suck in air and force it down onto the chemical adsorbent. The heat needed to later release this CO2 is supplied by a hydrothermal vent nearby – if you’ve ever been to Iceland, you know they have tons of these. The siphoned-off CO2 is then mixed with water and sent deep into the ground where it will react with basalt rocks and begin a process of mineralization. Although the mineralization may take up to 2 years, it is a near-permanent solution as the CO2 can never go back to the atmosphere and trap heat again. What is even better is that this complete process is powered by renewable energy from nearby geothermal and hydroelectric plants.
While afforestation and increasing the green cover have been touted as great ways to regulate the temperature, these measures are often temporary as when the plant dies the CO2 is released back into the atmosphere. The uptick in forest fires this past year has been indicative of how much more frequent this is as compared to imagining the average age span of a tree. Converting CO2 to rocks is a more permanent solution in comparison. Working around the clock, Climeworks estimates that the plant will remove up to 4000 metric tonnes of CO2 from the atmosphere each year. To put that number in perspective, during the last year, we released 33 billion metric tonnes of CO2 even with the pandemic in full effect.
In Texas, they make ‘em bigger! Not to be left behind the Europeans, the oil company Occidental is partnering with Canadian firm Carbon Engineering to build the largest DAC plant in the world and is expected to begin construction in 2022. When fully functional, the plant is expected to remove up to 1 million metric tonnes of CO2 from the atmosphere each year. While these numbers are promising, they aren’t at the scale yet to help put a dent in the amount of CO2 we generate. As per the UN, carbon removal technologies will be necessary to remove 1 trillion tonnes of CO2 by the end of the century to limit global warming to 1.5C in line with the Paris Climate Agreement.
Even though these numbers may seem small in the grand scheme of things, it is a step in the right direction. According to the Economist, it costs Orca around $600-$800 to sequester one metric tonne of CO2, which is in turn sold at $1200 a tonne to offset CO2 emissions. Even at this rate, it has sold over two-thirds of the total CO2 it will sequester over its entire lifetime. With big names like Microsoft and Swiss Re as its customers, we can only hope that there will be enough investment for this to be the next upcoming industry of this century!
