Democratized Direct Air Capture
What is the problem?
Climate change is one of the largest risks to human civilization. It has the potential to disrupt our economy, social life, and all institutions we have built over the past several thousand years. Carbon dioxide buildup is the signature marker for climate change. We need to remove accumulated carbon dioxide in the atmosphere. In this blog, we discuss how we can take on a huge environmental issue that will be key in the fight against climate change: carbon capture.
The concentration of CO2 in the atmosphere is 421ppm, and rising every day. Besides stemming the tide of CO2 emissions, we also need to remove existing CO2 in the atmosphere to avoid the worst effects of climate change. In order to do that, we have to create and improve technologies that allow us to grab the CO2 out of the air and store it underground. These technologies are called Direct Air Capture (DAC). However, DAC companies face significant challenges because their facilities require a lot of land, energy and money in order to capture a significant amount of carbon.
The following graph by Herzog  shows calculations why it takes a lot of land and energy to run a DAC facility:
As shown above with the orange curve, in order for a DAC facility to capture 1 million tons of CO2 per year at 90% utilization, capturing 75% of the incoming CO2 from air moving at a linear velocity of 1.5 m/sec would require a cross-sectional area that’s slightly over 40,000 square meters. The high energy costs come from passing large amounts of air through this large area. Admittedly, these carbon capture facilities are “beautiful monstrosities” — beautiful in the sense that they are capturing carbon dioxide, but monstrosities in that they are huge, ugly eyesores. Given the scope of the world’s carbon dioxide problem, carbon capture needs to be scaled up to a large degree. That means a rapid increase in the number of DAC facilities, implying they have to be everywhere in the near future. The problem is, nobody wants a monstrosity in their backyard.
A different way of tackling the problem
We need to reimagine DAC and fix the problems associated with DAC monstrosities. At Hago Energetics, we are building a new kind of carbon capture device that will be housed in a cargo trailer and can be attached to automobiles and trucks, so it gets pulled along for the ride. Our goal is to create a DAC unit designed to capture carbon dioxide from ambient air while the vehicle is in motion. If you attach one to your vehicle, every time you drive — no matter how short or long the trip — you will be doing your part to mitigate climate change.
What are our advantages over competing companies, and why is this technology unique?
We believe the way forward is to miniaturize carbon capture facilities to fit on the backs of automobiles and trucks. Whereas the foremost carbon capture firms operate just one or two football field-sized facilities, we want to democratize carbon capture by operating thousands of trailer-sized devices.
How does it work, you might ask? Basically, as the vehicle is moving, air will flow through holes in the side of the trailer, to obstruct the wind and slow it down. From there, the air will go into a cavity which contains a solid sorbent, which is encased in a removable cartridge. The CO2 sticks onto the sorbent. Then the trailer is brought to a central station, where the customer exchanges the CO2-laden cartridge for a new one and is paid for it. The CO2-laden cartridges will be heated up at that central location to “unstick” the CO2 from the sorbent. Finally, that CO2 is isolated so that it can be pumped into the Earth, or used in some other way, such as agriculture or fuel production.
A possible idea to further enhance revenues would be to sell advertising on these trailers, just like many trucks already do all over the country. This advertising could benefit the entire realm of climate change mitigation, because advertising space could be prioritized for companies and startups that are working to address and solve climate issues.
What are some effects of using this technology?
The long term goal is to reverse climate change by reversing the flow of carbon dioxide into the atmosphere. However, there are some unknowns with these technologies. A car hauling a trailer will experience drag, and lose efficiency of motion, which will reduce the fuel efficiency of the vehicle to an unknown extent. Also, a life cycle analysis would need to be done, to gauge effectiveness of carbon dioxide reverse flow. It is conceivable that this technology would work best for electric vehicles, to avoid the DAC device using some of its bandwidth to capture emissions from the vehicle itself.
What is the future of this technology?
Our game plan is to get everyone involved in the capture of carbon dioxide, and reward them for their help in doing the capturing. Our hope is that all future vehicles, especially if they are powered by electricity, will make use of this technology. A widespread adoption of carbon capture is a critical step towards mitigating climate change. We think it’s a future worth fighting for.
This blog was written by Emmett Novick and Megan Ferris as interns at Hago Energetics, Inc. Emmett is a junior at Johns Hopkins University majoring in Environmental Science. Megan is a 2020 graduate of the University of Connecticut, where she majored in Environmental Science.
Hago Energetics is a startup whose mission is to contribute to reversing global warming by tackling the biggest problems facing our environment, to create an abundant future for generations to come. If you wish to support this project, please visit our Indiegogo page at: https://www.indiegogo.com/projects/suck-carbon-out-of-the-atmosphere#/
Citations:  Herzog, Howard. “Direct Air Capture: A Process Engineer’s View (Low-Carbon Energy Center Webinar).” Youtube, 4 Feb. 2021, www.youtube.com/watch?v=9uRHKnQ3b5s&t=3s. Accessed 4 May 2021.