Cemvita’s fuel could approach being carbon neutral because the microbes are consuming carbon dioxide, says Moji Karimi, Cemvita’s CEO. The fuel would still produce emissions when burned, but they would be partially offset by the carbon that was captured to make it.
As for the light the microbes require, Cemvita will likely be using artificial light inside reactors, Harris says. While sunlight is free, relying on the sun would place constraints on how and where the company could build its production plants.
Cemvita is far from the first company to try making fuels with engineered microbes. Companies like LS9, founded in 2005, and Joule Unlimited, founded in 2007, captured large investments and excitement in the biofuels boom. Eventually, most of these efforts sputtered to a halt or pivoted away from fuels. LS9 was sold off in 2014, and Joule shut down in 2017.
Microbial fuel companies may face a different world today, says David Berry, a cofounder of Joule Unlimited and LS9, who is now a biotechnology investor at Flagship Pioneering. Tools for genetic engineering have improved dramatically, Berry says. Researchers today are able to find and test genes much faster, and the techniques for incorporating them into microbes’ genetic material have grown more precise.