Interview with Peter Psarras
This piece originally ran in MIT’s The Engine and is republished with permission.
Peter oversees the direction of Jennifer Wilcox’s lab, focusing on CO2 removal and carbon capture. His research involves techno-economic and life-cycle assessments of CCUS and CO2 removal systems, specifically in identifying regional opportunities for deployment.
Many of those communicating revolutionary technologies, especially with regards to climate change, struggle with capturing the scale of the challenge. How do you put the work ahead into perspective?
When I talk about scale, it’s about the rate at which we need to grow CCS (carbon capture and sequestration) processes—essentially an order of magnitude every decade. It helps to break it up like that, it translates our 2050 goals to what we must achieve today.
In terms of actual volumes of CO2 that need to be processed, I use the analogy of the growth in mobile phone popularity since the 1990s. Back then a mobile phone was a clunker, a luxury item, and now there are more than one per capita in the world. That’s astonishing growth! That’s basically the scaling that we need to do with CCS in terms of units of CO2 moved.
On the other hand, articulating the full scale of the challenge can quickly get terrifying and be viewed as putting the cart before the horse. As an example, I just helped the American Chemical Society do a video on CCS in which they were trying to calculate the amount of air that would need to be processed—and it is essentially half of the whole atmosphere.
To many, CO2 removal and carbon capture sound like the stuff of science fiction—can you talk about some of the most promising approaches and their significance?
We can look at what’s actually been proven and what’s been practiced for years—CO2 scrubbing and point source capture. It’s always more efficient to go those routes (than direct air capture) — just block it from getting into the atmosphere in the first place. There are a lot of arguments about how appropriate or costly these approaches are, but none of those arguments, in my mind, is aligned with the state of climate emergency we find ourselves in. Think of it this way—your room is on fire; are you going to get out a whiteboard and argue about what window you’re going to escape from?
Anything that plays on the Earth’s natural carbon cycle is interesting to me. We study mineral carbonation in our lab, which is essentially an enhanced weathering process—you get capture and storage in one step and you obviate the need for most of the infrastructure associated with other approaches.
Which approaches excite you the most?
We’ve had promising ideas for many, many years, but there’s never been a demand for CO2-derived products until now. We’re seeing this ridiculous surge in demand. So much so, that in 5 or 10 years, we’ll see a significant penetration of CO2-derived goods in the marketplace. But there are still barriers to adoption, especially with carbon storage—that approach is far more difficult than we anticipated, both technically and from a regulatory standpoint.
I have to mention Heirloom Carbon, co-founded by one of our students. Heirloom is commercializing a technology that enhances carbon mineralization, a natural geologic process, using natural and earth abundant minerals like alkaline oxides that can bind CO2 at ambient conditions. Careful engineering can enhance the kinetics from perhaps years to just days.
I was an author on California’s Livermore Lab “Getting to Neutral” report from 2020; in it, you see waste biomass as a major component of the state’s decarbonization initiatives. You see the same thing in Princeton’s Net-Zero America report. Using waste biomass as a feedstock we can produce hydrogen and CO2. If the CO2 is stored away securely, the hydrogen has a negative carbon footprint and this opens the door to a number of potentially carbon neutral products using H2 and CO2 as co-feedstocks, like plastics or fuels.
What gives you hope?
The best minds are coming to the table to solve these challenges. And I’ve also seen a real shift to humanitarian elements, where for so long climate change was cast as an environmental problem. We’re seeing many more people realize that this is our future—that our behavior directly impacts that future. All this, even in the face of an adversarial political climate, is hopeful. We’ve realized that we can’t say “2050” like it’s a million years away anymore. The practice round is over.
From a practical perspective, I am happy at the amount of scrutiny this space (CCS) is receiving. It makes it next to impossible for bad actors to continue with any type of market or regulatory manipulation. Meaning that we will get better data and better results with approaches that truly work.