Undoing the damage

Is MechanicalTree a better and more scalable carbon capture solution?

Carbon mitigation is something that the world is now running after. We, humans, have caused irreversible damage to Mother Earth by emitting carbon into the air that is making the world a warmer place. 

Can we undo this? Human behaviour is something that takes decades or even more to change or adapt to new behaviour. Can we stop the damage?

While we can gradually change our behaviour to responsible consumption, efforts are in place to remove the existing carbon from the atmosphere. 

This has led to the innovation of innovative technologies that can effectively fight climate change. 

Mechanical tree? Is that even possible? 

One such concept is the mechanical tree -- a concept of collecting carbon from the air with the help of technology. 

We produce this carbon every day by driving cars, using air conditioners, eating foods, making waste etc. While fossil fuel is the biggest source of carbon emission, other industries also emit carbon to some degree.

The Arizona State University Centre for Negative Carbon Emission is leading the way in finding a technology-based solution to carbon capture from the atmosphere, recycle, and reuse it as an industrial gas. 

ASU in its Tempe campus has installed the first of its kind MechanicalTree in partnership with Dublin-based Carbon Collect Ltd. It is expected to become a major technology in the global fight against climate change. 

This prototype of a MechanicalTree features a metal column and five-foot diametre disks, with each disk holding six leaves. Once completed, it will be a 33 feet (10 metres) installation. 

These mechanical leaves will store the collected carbon in a nine feet (2.7 metres) tall canister. Carbon Collect will make commercially available devices if the project is successful.

How it differs from other carbon capture technologies 

Like most other carbon-capture technologies, MechanicalTree is also based on the Direct Carbon Capture (DAC) process. Traditional DAC approaches have been constrained by the excessive cost of the capture of CO2, dependency on energy-intensive processes, and finally challenges in scaling. 

MechanicalTree first separates the CO2 from the ambient air and then permanently removes CO2 from the atmosphere. 

The separation process involves the chemical or physical separation of carbon, capturing and purifying it for industrial use or sequestering it in underground geological formations.

When the tree-like column is fully extended and its disks spread apart, airflow contacts the disk surfaces and the CO2 is bound up by a special sorbent material. During regeneration, the disks are lowered inside the canister. 

Inside the chamber, the CO2 is released from the sorbent. The released gas is then collected, purified, processed, and put to other uses, while the disks are redeployed to capture more CO2. When running constantly, it can remove 200 pounds (90 kg) of carbon every day.

Is the technology scalable? 

Carbon Collects expects that the geometry and dimensions of the capture units will enable easy scaling. While many DAC approaches use a high-power blower or fan, MechanicalTree can remove CO2 from the atmosphere without the use of blowers or fans. 

This makes it a passive, lower cost, and scalable solution that is commercially viable. 

Carbon Collect claims to have overcome the economic challenges of Direct Air Capture solutions through a proprietary passive Direct Air Capture (PDACTM) technology. 

Professor Klaus Lackner founded the idea of a mechanical way of carbon extraction from the earth's atmosphere. In 1999, he was the first scientist and academic to suggest that CO2 can be artificially captured from the earth's atmosphere to tackle global warming. 

He is the director of the Centre for Negative Carbon Emissions and a professor at the School of Sustainable Engineering and the Built Environment of the Ira A Fulton Schools of Engineering, Arizona State University. 

Lackner's research interests include closing the carbon cycle by capturing carbon dioxide from the air, carbon sequestration, carbon foot-printing, innovative energy, and infrastructure systems and their scaling properties, the role of automation, robotics, and mass-manufacturing in downscaling infrastructure systems, and energy and environmental policy.

Some scepticism

In the Paris Agreement, parties to the UNFCCC reached a landmark deal to accelerate and intensify the actions and investments needed for a sustainable low-carbon future, most of the countries in the world will not meet the 2030 climate goal.

Our consumption behaviour is the root cause of all the problems. Why don't we just change our behaviour that caused the environmental damage and made the climate more extreme? 

The root cause of this problem is our consumption behaviour. It is very unlikely that the world will shift toward responsible consumption tomorrow. That's why billions of dollars are being invested in DAC technology. 

The US Department of Energy announced in May that it would make a $3.5 billion investment to construct four DAC plants. 

Private investments have also been made by Google, Facebook, Tesla, and investment firms.  

However, there is no proven business model for carbon removal. Critics also fear that it will only slow down the green energy transition and that DAC is another way of doing billion-dollar business in the guise of the promise of a sustainable future. 

And last but not the least, ending fossil fuel is the only way to stop destroying the environment and endangering the climate.

Meer Ahsan Habib is a Hubert h Humphrey Fellow at Arizona State University. Twitter @meeriyadh.