The global food system is responsible for roughly 25% to 35% of all human-caused greenhouse gas emissions today (depending on how you tally them up), and much of that comes from animal agriculture. Alternative food sources could help feed the world while cutting climate pollution.
As climate change pushes weather conditions to new extremes, it’s going to be harder to grow food, says LanzaTech CEO Jennifer Holmgren. The company’s current specialty, sucking up waste gases and transforming them into ethanol, is mostly used today in places like steel mills and landfills.
The process the company uses to make ethanol relies on a bacterium that can be found in the guts of rabbits. LanzaTech grows the microbes in reactors, on a diet consisting of gases including carbon monoxide, carbon dioxide, and hydrogen. As they grow, they produce ethanol, which can then be funneled into processes that transform the ethanol into chemicals like ethylene or fuels.
A by-product of that process is tons of excess microbes. In LanzaTech’s existing plants where ethanol is the primary product, operators generally need to harvest bacteria from the reactors, since they multiply over time. When the excess bacteria are harvested and dried, the resulting powder is high in protein. Some plants using LanzaTech’s technology in China are already selling the protein product to feed fish, poultry, and pigs.
Now, LanzaTech is expanding its efforts. The company has identified a new microbe, one they hope to make the star of future plants. Cupriavidus necator can be found in soil and water, and it’s something of a protein machine. The company says that after growing, harvesting, and drying the microbes, the resulting powder is more than 85% protein and could be added to all sorts of food products, for either humans or animals.