Instead of air conditioners contributing to climate change, scientists have developed a plan to retrofit units with technology that would make them part of the solution.
The plan, which is outlined in Nature Communications, is to use technology that can pull carbon dioxide out of the atmosphere and make it part of the air conditioning unit. That way HVAC systems could become part of the solution, not the problem.
As the paper points out HVAC systems move a lot of air and machines that capture carbon dioxide from the atmosphere also move large volumes of air.
So why not put the two together. Air conditioners could be used to not only capture CO2, but transform it into a fuel.The concept, called crowd oil, is still in development but it has the potential to combat climate change, the authors said.
Led by chemical engineer Roland Dittmeyer at Germany’s Karlsruhe Institute of Technology, the researchers propose a system of modular components, powered by renewable energy, that would extract carbon dioxide and water from the air and convert them into hydrogen.
A multistep chemical process is then introduced to transform that hydrogen into liquid hydrogen fuels.
“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 authors said.
Technology to capture carbon dioxide directly from the air is not new. However, retrofitting air conditioners with this technology to capture Co2 and converting it to fuel is very new.
According to Nature the ultimate aim is to reduce the amount of carbon dioxide in the atmosphere.
The authors calculate that a capture system installed in the Frankfurt Fair Tower in Germany could remove over a tonne of carbon dioxide from the air per hour. The same systems implemented in Germany's 25,000 supermarkets could capture around 1,000 tonnes an hour.
The first commercial “direct air capture” plant, built by Climeworks in Switzerland, captures 900 metric tonnes of CO2 per year, while an apartment building with five or six units could capture 0.5 kg of CO2 an hour with this proposed system.
Obviously, there are some major challenges to overcome. Firstly, if the air conditioners are run on electricity powered by burning fossil fuels, it defeats the whole purpose. That means basically switching over to renewable energy as quickly as possible.
The paper's authors estimate that to do this in Germany alone would mean covering half of all roof space in the country with solar panels.
"This means that buildings populated by humans will act like inhabited technical photosynthesis systems, which is a very intriguing idea given the ever-growing number of human beings on this planet," the paper reads.
One bonus is that the fuels created by the system could be stored collectively and used during times when solar and wind power collection is not possible. But this brings up another challenge, which is how and where to store all the fuel that would be created from the A/C captured carbon.
Clearly there are some challenges that need to be addressed but demand for cooling is growing at such a rapid pace surely all ideas to tackle global warming should be considered.