The recent IPCC The report and the UN report on climate change make it clear: it’s time to start working on something to combat the amount of COtwo in our environment. There are hundreds of startups working on that “something”.
Some are working on direct air capture technologies, like Climeworks, which raised $110 million in April. These engineered solutions extract carbon from the atmosphere using expensive and complicated machinery and inject it back into the ground for long-term storage.
But there is a more efficient way of capturing carbon that has been around for much longer: photosynthesis. Nature-based solutions tend to focus on this approach; think tree planting or soil restoration. These have been championed by non-profit organizations such as The Nature Conservancy and American Forests.
In the world of climate mitigation, nature-based solutions are cheap and generous, but are considered short-term carbon removals because much of the carbon is at risk of being released into the atmosphere if a fire burns through a forest or a human cuts down the trees. Engineered solutions are much more durable and measurable, but they are expensive and in short supply.
Living Carbon, a San Francisco-based startup that came out of stealth mode in March, is working at the intersection of nature and engineered solutions to climate change. The company is genetically modifying the trees so they can store more carbon.
“Plants have the unique power to fix carbon from the atmosphere: photosynthesis,” said Living Carbon’s scientific director, Yumin Tao.
The startup wants to improve that power by creating trees with greater photosynthetic capacity.
The idea is to “use that natural process…with the added storage and added durability of an engineered solution,” CEO Maddie Hall said of her company.
Breeding and engineering plants to be bigger and stronger is not new. It’s something the world of food and agriculture has been doing for a long time. Even the specific scientific innovation Living Carbon is using: enzymes to bypass the inefficient biological pathway called photorespiration, which causes plants to release some COtwo returns to the atmosphere, wasting some of the energy produced by photosynthesis, has been a field of research for decades. But instead of using those tools to grow more food, more easily and cheaply, Living Carbon is turning that biological innovation into carbon sequestration.
“I was fascinated by this idea of, could you steer a lot of the plant biotech work that is used specifically to focus on the food supply, could you steer it around solving a new problem: carbon removal?” Hall said.
Living Carbon’s real innovation was taking the genetic engineering process of suppressing photorespiration that was developed for tobacco plants and putting it into trees like hybrid poplar and loblolly pines. According to Tao, Living Carbon has spliced genes for enzymes from gourds and algae into trees so that carbon dioxide is broken down within the chloroplast, resulting in a more efficient CO conversion process.two into sugar with a smaller amount released into the atmosphere. This process builds on a natural one found in certain more efficient photosynthetic plants called C4 plants, which include corn and sorghum.
“More carbon fixed means faster growth and bigger plants,” Tao said. And because, according to Tao, about 50% of a plant’s biomass is carbon, bigger plants mean less carbon in the atmosphere.
In a research paper published by Living Carbon that has not yet been peer-reviewed, an experiment in a controlled indoor growing environment found that over five months, trees genetically modified with Living Carbon technology had a 53% increase in weight above ground than the control plants
The next step is for Living Carbon to field test its genetically modified trees. It has a four-year partnership with Oregon State University to continue research on its trees, and this month the company began planting with private owners in Pennsylvania, Georgia and California.
Living Carbon is working on the new flourishing carbon economy. You will not make money by selling the GM trees to landowners, but will instead provide the trees for free and retain the rights to the carbon credits generated by the plantation projects. You can then sell those credits to corporate buyers like Microsoft and Salesforce who have net-zero ambitions for their companies. Owners also get a share of the sales revenue.
Organizations such as Verra and The Gold Standard are used to verify, assess and award carbon credits to projects. Due to genetic enhancements that make Living Carbon trees larger and therefore more carbon-bearing, they will earn more credits than a project using regular trees if this is held constant.
“Landowners right now can plant trees that have elite genetics and grow faster than traditional trees,” Hall said. “It’s enhancing growth for carbon removal purposes.”
Living Carbon is also working to reduce COtwo emissions from the other side by finding genes that slow the decomposition process. The carbon stored in trees can never really be permanent because trees are living organisms that will eventually die and are always at risk from unpredictable wildfires, but slower decomposition is a way to prolong the life cycle, reducing COtwo released during this process and the amount of highly flammable wood chips in the forest.
“When you globally reduce the rate of decomposition, you also globally increase the carbon pool in the soil and keep that carbon out of the atmosphere longer,” said Patrick Mellor, co-founder of Living Carbon.
It is also exploring whether it can engineer trees to grow on land that previously couldn’t support them, such as old mining areas, by creating trees that have a higher tolerance for nickel or other heavy metals. According to Mellor, Living Carbon has shown that some of the trees in its research have a higher tolerance for nickel and a lower rate of decay, but those studies are still in the indoor growth testing phase.
Trees are one of our best and most popular tools to combat the climate crisis. Using human innovation to make them even more powerful has attracted a $15 million Series A for the three-year-old venture, led by Lowercarbon Capital, Goat Capital, Prelude Ventures and others.
“The ability to use the energy-efficient nature of biology, and to do it in a way that is capable of permanently sequestering carbon, that’s the Holy Grail,” said Hall.