Negative Carbon Emission

Tech Primer

E8 has always been committed to accelerating the transition to a cleaner world by investing in and fostering cleantech enterprises. We believe that investing in climate mitigation technology is one of the most important ways to help lower carbon emissions.

 

 Negative Emission Technologies (NETs)  have been shown to remove carbon from the atmosphere and sequester it. In our current state of constant emitting, this is as necessary as preventing those CO2 emissions at the source. Some NET methods are very common, such as reforestation (replanting an area with trees), afforestation (planting trees on an area not previously forested), and soil sequestration (transferring carbon dioxide to the soil for storage).

 

Other NETS, such as Coastal Blue Carbon, Bioenergy with Carbon Capture and Sequestration (BECCS), Direct Air Capture, and Carbon Mineralization are less widely developed with some scientific unknowns. Many of the companies that we have chosen to highlight in the Good Carbon Gifts catalog are using and developing these NET strategies. You can find more detail on the scientific processes behind their business models below.

Coastal Blue Carbon

Coastal Blue Carbon technologies increase the carbon stored in plants or sediments in coastal ecosystems such as mangroves, tidal marshlands, seagrass beds, and other tidal/salt-water wetlands. This means that we can take carbon and store it in already existing coastal ecosystems safely, thus decreasing carbon emissions in our atmosphere.

 

Terrestrial Carbon Removal and Sequestration

Terrestrial Carbon Removal and Sequestration includes practices such as reforestation, afforestation, and agricultural practices that increase soil carbon storage. These practices are widely known and have been developed over many decades. Sheep Inc. makes their knitwear using regenerative agriculture which increases natural carbon sequestration and helps to mitigate the impact of their farming methods. You can also be a part of this climate solution by purchasing carbon removal credits from Nori, who works with farmers to remove carbon from the atmosphere and store it in their soil via sustainable farming practices.

 

Bioenergy with Carbon Capture and Sequestration (BECCS)

BECCS technologies use plant biomass to produce energy while capturing carbon during the process. Pyrolysis/gasify techs thermochemically convert biomass into volatile liquids or gases that provide energy when combusted, but also produce carbon in the form of biochar that can be sequestered in soil for hundreds of years. The biochar can then be used in your home garden or lawn. Just take a look at Wakefield Biochar’s line of soil conditioning products. Wakefield believes that with the amount of carbon they can sequester through this process we can save the world, and they may be right; the potential rate of CO2 removal for BECCS is currently the highest of any NET.

Direct Air Capture

Direct Air Capture processes capture CO2 from the air and concentrate it so that it can later be injected into a storage reservoir. You can help companies like Climeworks remove CO2 through direct air capture technology by purchasing carbon removal subscriptions. They note direct air capture as being a great approach because it has the smallest land and water footprint of all NETs. The impact of these technologies has amazing potential. As they are scaled, they could feasibly remove significant amounts of carbon from the atmosphere.

Carbon Mineralization

Carbon Mineralization technologies are a form of “accelerated weathering,” where CO2 from the atmosphere forms a chemical bond with a reactive mineral on the surface and in the subsurface of exposed rock. Climeworks has partnered with Carbfix, a world expert in this process. Climeworks captures the carbon dioxide through direct air capture technology, then Carbfix mixes that carbon dioxide with water and pumps it underground. This carbon dioxide mixture reacts with basalt rock and within a few years, turns it to stone, storing it safely in the earth.

 

 

In Summary – here’s a table that compares the (a) cost and (b) potential emissions capture potential, along with limiting factors and benefits.  Stay tuned as this sector grows!

NET process backgrounds and table taken from:

National Academies of Sciences, Engineering, and Medicine. 2019. Negative Emissions Technologies and Reliable Sequestration: A Research Agenda. Washington, DC: The National Academies Press. doi: https://doi.org/10.17226/25259.