Using the mineral olivine to remove carbon through natural weathering
greenSand achieves CO2 removal by exploiting the natural weathering of a variety of minerals covered under the classification of Olivine. This is a reaction that undeniably occurs in nature and so the removal of atmospheric CO2 is not a point of debate. Compared with other CO2 removal companies, greenSand has operating for many years and has removed uncertainties around application (e.g., public acceptance, logistics, sourcing, sales). greenSand’s method is remarkably simple and represents replacing an existing product. These are strong benefits of the greenSand method that lend credence to their ability to scale their process.
greenSand should be applauded for attempting to quantify the timing of CO2 credits it provides to customers. It is a tricky calculation not only for greenSand’s method, but also for CO2 removal methods that utilise biomass. This ‘real-world’ uncertainty should not be taken as a unique downside to the GreenSand method, it exists in all CO2 removal processes given their early-stage nature.
All told, the greenSand process has a number of very appealing traits:
- it does not rely on a CO2 transport or storage infrastructure;
- it involves no new energy consumption, simply replacing current mining and milling operations with a different rock;
- it is both visible (the public is aware of CO2 removal) and invisible (it is something that is already well accepted by society: grinding rocks);
- it is cheap and simple; and
- it is highly amenable to electrification (lower costs and higher CO2 removals as renewable energy expands).
What remains to be fully vetted is how close greenSand can come to achieving their reported CO2 reductions. greensand is undertaking extensive testing with research institute partners to continue to validate their model for estimating CO2 removal. We have a close relationship with the researchers working on this project and will assess the outputs of this testing.
Additionality → 2/3
Negativity → 0.74
Permanence → 1000+years
Source: CarbonPlan, 2020
Written in collaboration with Dr. Corey Myers and Dr. Martin Chan