Negative emission technologiesHow Microorganisms Can Help Us Get to Net Negative Emissions

Published 8 April 2021

To reduce our reliance on fossil fuels and reduce greenhouse gas emissions, society has increasingly tried turning to plants to make the everyday products we need. But what if plants could be removed from the picture, eliminating the need for water, fertilizer, and land? What if microbes could instead be harnessed to make fuels and other products? And what if these microbes could grow on carbon dioxide, thus simultaneously producing valuable goods while also removing a greenhouse gas from the atmosphere, all in one reactor?

Many of the common items we use in our everyday lives – from building materials to plastics to pharmaceuticals – are manufactured from fossil fuels. To reduce our reliance on fossil fuels and reduce greenhouse gas emissions, society has increasingly tried turning to plants to make the everyday products we need. For example, corn can be turned into corn ethanol and plastics, lignocellulosic sugars can be turned into sustainable aviation fuels, and paints can be made from soy oil.

But what if plants could be removed from the picture, eliminating the need for water, fertilizer, and land? What if microbes could instead be harnessed to make fuels and other products? And what if these microbes could grow on carbon dioxide, thus simultaneously producing valuable goods while also removing a greenhouse gas from the atmosphere, all in one reactor? Too good to be true?

Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have made good progress in turning this technology into reality. Led by scientist Eric Sundstrom, a research scientist at the Advanced Biofuels and Bioproducts Process Development Unit (ABPDU), and postdoctoral scholar Changman Kim, the project combines biology and electrochemistry to produce complex molecules, all powered by renewable energy. With carbon dioxide as one of the inputs, the system has potential to remove heat-trapping gases from the atmosphere, or in other words, a negative emissions technology (NET).

The scientific community as well as policymakers are reaching consensus that NETs can be an important tool in the fight against climate change by reducing the concentration of greenhouse gases in the atmosphere. Berkeley Lab researchers are pursuing a gamut of negative emissions technologies (rRead about “A Sponge to Soak Up Carbon Dioxide”). Sundstrom’s project was launched two years ago under the Lab’s Laboratory Directed Research and Development (LDRD) program.

Berkley Lab’s Julie Chao talked with Sundstrom on a technology to turn electrons to bioproducts.

Julie Chao: How did this project start?
Eric Sundstrom: At the ABPDU, we work across a range of products. Virtually anything made by the chemical industry – you can find a way to use microbes to make those building block molecules, and then replace the petrochemical or even the agricultural equivalent of that product. There’s a lot of power to make virtually anything with biology. It’s just a question of whether it’s economical to do it.