Sucking in a million tonnes of CO2 a year
In Scotland, the world’s biggest CO2 collection plant is in the pipeline.
With so many plans and promises for carbon reductions being based on technologies that do not even exist yet, any attempt to develop practical and costeffective carbon capture and storage should be examined closely, and critically. Some projects focus on capture and storage during the burning of coal, gas and oil, but there are also projects that plan to collect carbon dioxide already emitted. The world’s biggest such facility is being planned for Scotland, and if successful will remove a million tonnes of CO2 from the atmosphere annually.
It uses a chemical process, sucking in air through large turbines, then directing it across a plastic surface covered in a solution of potassium hydroxide. Carbon dioxide from the air binds to potassium hydroxide like a salt. The resulting solution is then distilled to raise the concentration of CO2, and finally, the salt can be pressurised into tablets. When the tablets are burned, CO2 can be collected as gas in pressurised bottles, with other ingredients separated and reused for the collection of further CO2.
There remains the problems of cost and storage: the storage plan is for collected CO2 to be used industrially, or deposited so deep it purportedly cannot escape. The exact location has not been decided; the Canadian company behind the technology, Carbon Engineering, hopes to license it to a UK company to get the plant running by 2026.
A million tonnes a year is equivalent to the effect of 40 million trees, yet it pales beside the output of a single coal-fired power station. The Eraring power station on Lake Macquarie, NSW, emits an estimated 15-17 million tonnes of carbon dioxide annually.