Removing carbon dioxide from the atmosphere may seem like an immense challenge, but even greater obstacles await humanity if it does not actually begin to act to reduce the concentration of the gas in the environment. For this reason, research carried out around the world tries to bring a solution to this problem: in an article published last week by the journal Nature Communications, scientists suggest that the emergency implementation of CO2 purifiers would be one of the techniques that would boost the undertaking. However, the action would require financing equivalent to that dedicated to wars by governments and companies.
Through a technology called Direct Air Capture (free translation of Direct Air Capture – DAC), mechanical systems that currently use a liquid or solid solvent capable of separating CO2 from other gases, perform the task.
Examples of such devices are those marketed by the Swiss company Climeworks, which already has 15 active machines on the European continent. The operations are powered by renewable geothermal energy or produced by burning waste: a fan sucks the air and passes it through a collector, inside which there is a filter that, in turn, directs the pollutant underground, where it is finally kidnapped.
Canadian Carbon Engineering, with giant fans, captures the air and directs it to a tower-like structure, in which a solution of potassium hydroxide binds chemically to the CO2 molecules and removes them.
Then, the pollutant is concentrated, purified and cleaned, and can be injected into the soil to extract oil and, in some cases, acting to neutralize emissions generated by the burning of fuels.
Both companies say they are ready to produce their devices on a large scale, and the potential market value of the technology could reach $ 100 billion in 2030, estimates point. Anyway, one doubt prevails: is it really worth it?
It is expected that the costs of such devices will gradually be reduced, but, in the molds found today, in addition to being expensive in relation to studied alternatives, they consume a lot of energy. Just to give you an idea, they would be responsible for a quarter of global consumption in 2100. Fortunately, methods under development are expected to decrease these unsightly rates – such as those of Australia’s Southern Green Gas and CSIRO, which are building solar-powered DAC technologies.
The interest of large companies can also bring benefits. Last year, Microsoft included the novelty in its negative carbon plans, and as other institutions follow suit, additional research funding could accelerate the emergence of more effective products, such as those promised by Elon Musk.
One of the great advantages of the air capture technique, experts argue, is that it requires less land and water than others, such as planting forests or storing CO2 in soils or oceans. Job creation is another attractive possibility, given the populations affected by the decline in the use of fossil fuels.