Behind the Scenes of our Article in Nature Sustainability

by Kathleen Alexander, co-founder and CTO

Image generated by DALL·E

"Can’t we just eat the fossil fuels?” Ian McKay had been asking this question for a while, and I answered it in the way that any of us standard-issue humans might: “Ian, that is a terrible idea.”

The idea had occurred to him after revisiting ‘Potatoes Made of Oil’^[¹^,²^] and reading (again) how many kcal of fossil fuels get burned to produce one kcal of beef. (Note: we’ve seen this value reported all over the map: from 10-100x^[³^,⁴^]. It’s a tricky calculation with wide error bars, but everyone seems to agree that it’s a lot more than 1x). When you’re Ian, you read this type of thing and think: 1) fossil fuels are sources of energy 2) humans need to eat sources of energy 3) why again are we bothering with cows and potatoes? 

When you’re me, it’s not so simple. Food is good and fossil fuels are gross. Also, I had spent my entire academic and professional career focused on developing technology solutions that would allow us to keep fossil fuels in the ground. The idea that we might intentionally extract fossil fuels in order to eat them sounded misguided on a professional level, and gross on a personal level. For some, ‘that sounds gross’ would, in fact, be a completely valid scientific reason to abandon a given line of inquiry, and we might have closed the discussion there. But it seemed plausible that there might be a better measure than ‘units of grossness’ to litigate the idea of eating fossil fuels.   

So we went to the figurative whiteboard (this was the summer of 2020, and literal whiteboards were not really a thing). We charted out all the ways we could imagine converting fossil fuels into food (i.e. fats, proteins, carbohydrates) and calculated the lifecycle emissions, land usage, and water usage for as many of the pathways for which we could find data. We then looked at literature data for emissions, land, and water intensity of agriculturally derived macronutrients, and the results were clear: fossil fuels might be gross (more on this later), but if humans ate them, it would be dramatically better for the planet than the current agriculture system. This work has now culminated—thanks largely to our talented colleagues in academia—in a recent article published in Nature Sustainability: Food without Agriculture^[⁵^].   

As described in the paper, a lot of the differential impact between synthetic and agricultural foods comes down to land use: we currently clear lands for pasture and crops, and the release of stored carbon that results from this land conversion is enormous. So far, humans have converted about 50% of the habitable land on the planet for agricultural use. The net release of carbon that was stored in former forests and soils into the atmosphere has already increased global temperatures by about 1-2 °C^[⁶^,⁷^]. When you then consider how that land is now used, you see how drastic a swing for the planet this really represents: Former carbon sinks become massive ongoing emitters of carbon. We found this graphic from a 2018 Bloomberg article to be a particularly compelling illustration of land use in the United States. Note just how much land is currently used to power our agricultural system, and in particular how disproportionate the land investment in agricultural animals is, no small part of which is the land used to feed the animals we feed ourselves. 

Merrill, D. & Leatherby, L. Here’s how America uses its land. Bloomberg (2018). 

The thought that shifting humans from eating animals and plants to eating fossil fuels could enable the reclamation of all of those lands—and the ensuing sequestration of vast amounts of atmospheric carbon^[⁸^]—was powerful. I even made this artsy slide about it:  

(Nonredeemable bonus points if you can guess why we named this Project 255) 

So what do you do when you have an idea that everyone will think is terrible but that you think might be able to make an enormous difference for the planet? I’m not sure what you would do, but what we did was take a closer look at the pathways we’d mapped out, this time focusing on technical viability and readiness, and we identified one of them—the synthetic production of fats—as having unusually high technical readiness, high economic viability, and high potential for impact.  

With so much stacked technoeconomic potential, we felt compelled to explore the commercialization potential of synthetic fat production, which brings us back to the topic of fossil fuels being gross. Let’s examine: Fossil fuels are made up of compounds, some of which are toxic and carcinogenic, some of which are inert in the human body, and some of which are ingredients in our food and cosmetics. The funny thing is, if you replace ‘fossil fuels’ in that sentence with ‘agricultural products’, the sentence will still be true. We have been socialized to think feel that synthetic compounds are not as good or safe for humans as their plant-derived counterparts; I’m sure it is possible to find examples to support this, but I am equally sure that there are counterexamples. The pro-natural bias we carry is a strong one, but it may not be the right metric to drive healthy (much less ethical) decision making when it comes to what we consume. After coming to terms with this ourselves (really just myself, Ian is exempt from the limitations of socialized thought and feeling), we were emboldened to find a lab space to try and make some synthetic fats and determine whether they would be safe to eat. Notably, we didn’t ask whether they would be good to eat. That’s a story for another day.  

Fast-forward to the present, and we’ve founded a company, Savor, that is commercializing the production of agriculture-free fats. The fats we make at Savor can be produced from fossil fuels like natural gas or from captured CO2 and green hydrogen—the latter of which would have lower net emissions than natural-gas-derived fats, but only in exchange for a higher cost. We have our work cut out for us both technically—making high purity and high-performance fats—and commercially—learning how to share our products and technology with the world in a way that addresses inevitable questions and concerns about safety and health. It’s been a fun journey so far: building a team, raising money, and overcoming the daily hurdles inherent to developing and scaling a new technology. We could not be more excited to bring these new fats to the world. Speaking of which, here is a picture of some unusual butter: 

Butter made from fossil fuels. I swear it tastes really good. The color is from beta carotene that we add because we have found that people like to see yellow-ish butter; the synthetic fats themselves are white. Photo credit: Ailin Zhang

It can feel like something of a miracle to be unearthing a new paradigm for food production, and perhaps it is another small miracle to make a new food and find that it is delicious. But societal paradigms and culinary pleasure are only a corner of what drives us. For us, success is measured in the concentration of atmospheric greenhouse gases and hectares of diverse ecosystems preserved or restored, and that work is only just beginning.   

Alright. Enough butter and “manifesto.” I know the only thing really on your mind right now is: should you go drink a glass of gasoline after reading this? It turns out that the LD50 of gasoline is surprisingly high, but the answer is: No, please don’t. 

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