Saved By The…Air Conditioner?
New Paper Proposes Carbon Sequestration From HVAC Systems
You have to like the idea carbon sequestration: if our ability to stop putting carbon into the atmosphere is limited, why not try taking it out? But it always seems to founder on a life-cycle analysis: it costs so much in energy to get the system working that you wind up producing more carbon than you withdraw. But now comes Roland Dittmaier of Germany’s Karlsruhe Institute of Technology and Geoffrey Ozin of the University of Toronto, with a new idea: use the HVAC system to do it.
What does HVAC have to do with anything? Simple: HVAC systems move a lot of air around, all the time. They can completely replace the air in a building from 5 to 10 times an hour. And if they can move air around, they can move carbon dioxide around — in fact, they already do. Thus, Dittmaier and Ozin
imagine a system of modular components, powered by renewable energy, that would not just extract carbon dioxide and water from the air. It would also convert them into hydrogen, and then use a multistep chemical process to transform that hydrogen into liquid hydrocarbon fuels. The result: “Personalized, localized and distributed, synthetic oil wells” in buildings or neighborhoods, the authors write. “The envisioned model of ‘crowd oil’ from solar refineries, akin to ‘crowd electricity’ from solar panels,” would enable people “to take control and collectively manage global warming and climate change, rather than depending on the fossil power industrial behemoths.”
The commenters in the article think it’s a promising idea, but seriously doubt that it can be done on a large scale. For me, though, the key lies in the dependent clause “powered by renewable energy.” It doesn’t matter how cool any new gizmo is: what matters is the life cycle analysis. And interestingly, none of the more skeptical views in the Scientific American article seem to question that. Arte Johnson would find this very intereshting.
Reader Comments
4 Replies to “Saved By The…Air Conditioner?”
Comments are closed.
About Jonathan
Jonathan Zasloff teaches Torts, Land Use, Environmental Law, Comparative Urban Planning Law, Legal History, and Public Policy Clinic – Land Use, the Environment and Loc…
READ more
The problem is that this is still only carbon neutral. The biofuel made then gets burned again. If it is made into a non-fuel feedstock, especially for plastic, it will be sequestered for a long period of time (hopefully somewhere other than in the ocean).
Agreed. Keep the stuff in the ground.
We need to remember the lesson of fossil fuels themselves. Coal was created when plants “invented” lignin in order to be able to grow taller and get into the sun. Lignin is a biopolymer of phenol (IUPAC, benzenol) unlike many plant tissues, which are polysaccharides. Bacteria were unable to break down lignin, so for the 60 million years of the Carboniferous (“I bear coal”) period wood was buried, and eventually all of that carbon was sequestered as coal. (And now we are bringing all of that carbon back out in a few generations – we burn over a cubic mile of coal a year.)
We also have some suggestion of an opportunity in that some creature (us) has invented a family of mainly carbon based materials that don’t biodegrade and hence might be a route to hiding some of the excessive carbon in the atmosphere. About 300 million MTonne of plastic is made a year, and if it could be made of feedstocks derived from carbon dioxide in the atmosphere instead of fossil carbon it would make a dent, though it would be preferable to sequester the plastic in some form other than microparticles in the environment – in India they make roads out of recycled plastic.
It is worth noting that though there are a lot of mechanical means of making alkanes and alcohols with carbon dioxide and renewable energy, biology does this as well. There are a lot of schemes to use micro and macroalgae (kelp) to make biofuels and feedstocks, which generally require much less expensive equipment than mechanical systems.
As a final note, natural kelp forests sequester substantially larger amounts of carbon provided they can be protected from predation by sea urchins. Unfortunately, the sea otters that ate them were hunted to near extinction for their fur and Pacific kelp forests died. Restoration of kelp forests and their guardians is something we “otter” be working on (see your California state tax return checkoffs).
That should be 300 MTonne, not 300 million MTonne.