.


Today's Popular Articles and Posts:

Can Synthetic Trees Tackle Climate Change?   By Haydn Dunn

 

 

I just listened to the Prime Minster of Trinidad and Tobago at the Commonwealth Heads of Gov't Meeting speak about implementing Carbon Capture and Sequestration (CCS) it's the same as Carbon Capture & Storage where the “capturing” process capture carbon emissions prevented from being released into the atmosphere, and the “sequestration” or “storage” of the captured carbon. “Capturing” carbon means separating out the carbon dioxide from all of the other gases and particulates often found in fossil fuel exhaust however capturing and compressing CO2 requires much energy and would increase the fuel needs of a coal-fired plant with CCS by 25%-40%

We all know that trees are great absorbers of CO2 and the idea of increasing the planting of trees to act as carbon sinks, especially in areas around coal plants and other offenders, has been floated around for a while. But can you make a better tree? A Columbia University professor thinks so. He and his company, Global Research Technologies, have created a synthetic tree that they say captures CO2 1,000 times faster than regular trees and without the need for direct sunlight.

Klaus Lackner, a physicist with the Earth Institute, first developed a prototype machine that would remove carbon dioxide directly from the air, called a ‘synthetic tree’. The design, which looks more like a cross between a rugby goal post and giant venetian blinds than a natural tree, is one of a countless number of so-called ‘geo-engineering’ projects that promise to reduce the effects of climate change.

 

As Lackner explains, the technology is similar to that used at coal plants to capture carbon from flue stacks, but can be used anywhere. Lackner notes that half of carbon emissions come from small sources, including cars and airplanes, and is usually nearly impossible to collect. But since the carbon dioxide in the air is actually very concentrated, the device required to collect it can be fairly small.
 
Lackner's goal is to make the synthetic tree highly efficient for its size. Compared to the amount of carbon dioxide that a large windmill can avoid generating, for example, a synthetic tree of equal size could collect several hundred times the amount of carbon dioxide that the windmill avoids.
Professor Lackner estimates that each ‘tree’ would cost £12,000 and over its lifetime would capture almost 20 times the amount of CO2 it consumed during its production and operation. The trees could be located close to depleted oil and gas reserves.

 


Is it good For Home use?


According to professor Lackner, A synthetic tree could be planted anywhere. A small one could sit like a TV on the lawn to balance out the CO2 emitted by one person or family.
But more practically, said Dr Lackner, a device the size of a barn would sit in the open air, near repositories for easy transportation and storage of carbon.

He estimated that 250,000 synthetic trees worldwide would be needed to soak up the 22 billion tonnes of CO2 produced annually.

Not everyone is rooted to the idea though.

 Massachusetts Institute of Technology engineer Howard Herzog thinks Dr Lackner's design will not hold together on the scale he proposes.
He said you would expend more energy in capturing the CO2 - in keeping the slats coated in absorbent and disposing of it - than you would save.
"Once the solvent captures the CO2, it holds it on tight," said Dr Herzog, "and it's going to take a lot of energy to break those bonds."
He said that much more research was needed on the technology.
"The idea of air capture is seductive and would really be great to have," said Dr Herzog, "but it's important to separate out the concept from the technical details."

Back to Environment