By Eloi Grignon, Ph.D. student, Member-at-Large for the GCI
Faced with a worsening climate crisis and growing food insecurity, humans have begun to produce food from the air. While you’d be forgiven for assuming this plot to be that of an Asimov story, it is, in fact, the reality that several start-ups envision for the future of agriculture. Indeed, a wave of firms have developed gas-to-protein technologies that employ bacteria to convert feed gases into an edible flour.
In truth, none of the technologies designed to date rely solely (if at all) on air. For instance, Solar Foods, a Finnish biotech company, combines carbon dioxide from the air with green (i.e. not derived from fossil fuels) hydrogen and water to feed a carefully selected bacterium. The result of this fermentation is their proprietary Solein protein, which they currently produce at a rate of 1 kg per day.1 Others in the gas-to-protein industry have developed their fermentation processes around different gases: Calysta uses methane supplied by the energy giant BP while Lanza Tech relies on the waste carbon monoxide generated by a nearby steel plant.1
The synthesized proteins are generally viewed and marketed as alternatives to other plant-based proteins, such as those derived from soy, whose cultivation is land-intensive and can come at the cost of intense deforestation.2 Here, gas-to-protein agriculture has the tantalizing potential to produce food on similar scales while requiring only a fraction of the area. A 2018 study estimated that widespread adoption (roughly 10-20% market share) of gas-to-protein could reduce farmland area by 6% and associated GHG emissions by 7%.3
Gas-to-protein agriculture may also help phase out animal-based proteins. One suitable target for replacement is fishmeal, the powder obtained from drying and grinding the bones and offal of commercial fisheries’ by-catch. Fishmeal, which is used as the primary source of protein for farm-raised fish, consumes approximately one quarter of the global wild fish catch and is strongly linked with the depletion of aquatic environments and collapse of local fisheries.1 As a more sustainable alternative, Calysta produces a bacteria-sourced protein with all the amino acids required to feed farmed fish. The potential impact is huge: Calysta’s CEO claims that the presence of a 100,000-tonne plant of synthetic protein can allow 500,000 wild fish to remain in the ocean.1
The boons of gas-to-protein agriculture are pushed to truly stupendous heights when CO2-consuming processes are employed. According to Solar Foods, the operation’s economic use of energy coupled with its inherent carbon sequestration could translate to a protein with only 1% of the carbon footprint of its plant- and animal-derived counterparts.1
Beyond the increased protection of forest and aquatic ecosystems along with huge water and energy savings, gas-to-protein agriculture has other, more intangible advantages. For instance, the liberation of food production from environmental dependence means that the protein’s annual tonnage need not be subject to environmental crises or day-to-day weather. Moreover, scaling production up or down can be achieved far more easily when no marginal land or animals come into the equation.
Although there is great promise for gas-to-protein firms to gain an established foothold, there remain several economic hurdles impeding widescale production. Chief among these is the high cost of green hydrogen – a key ingredient of many firms’ protein recipe. Green hydrogen is produced from the electrolysis of water and, as such, its price is contingent on the supply of low-cost electricity. It is hoped that the economies of scale associated with the advent of renewables will lower the price of electricity sufficiently to render gas-to-protein agriculture the economically favourable option. The balance may also be tipped in favour of gas-to-protein agriculture if alternative, non-monetary costs, such as those of land and wildlife, are factored into consumer decision-making.
The first agricultural revolution saw us take mastery of our environment and irreversibly change the course of human history. If gas-to-protein agriculture is to become a mainstay, could we now, 12 millennia later, be on the brink of witnessing an equally important turning point?
References
[1] Scott, A. (2020). Food from the air. CHEMICAL & ENGINEERING NEWS, 98(35), 18-21.
[2] Phillips, D. (2020). The Cerrado: how Brazil’s vital ‘water tank’ went from forest to soy fields. https://www.theguardian.com/environment/2020/nov/25/the-cerrado-how-brazils-vital-water-tank-went-from-forest-to-soy-fields
[3] Pikaar, I., De Vrieze, J., Rabaey, K., Herrero, M., Smith, P., & Verstraete, W. (2018). Carbon emission avoidance and capture by producing in-reactor microbial biomass based food, feed and slow release fertilizer: potentials and limitations. Science of the Total Environment, 644, 1525-1530.
[4] https://www.calysta.com/feedkind/. Accessed February 20, 2021.
[5] https://solarfoods.fi/impact/#bioprocess. Accessed February 27, 2021.
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