Elon Musk offers $100M prize for Gigaton Scale Carbon Removal

A four-year global competition to lock away CO2.

Peter Miles
Mar 1 · 5 min read
Elon Musk. Image — Flickr Creative Commons.

Elon Musk and the Musk Foundation are offering $100 million total prize money, for innovators and teams, to create and demonstrate solutions that can pull carbon dioxide directly from the atmosphere or oceans then lock it away, and which can be scaled up to gigatons of CO2 removal.

Named XPRIZE Carbon Removal, it will be the largest incentive prize ever offered.

Judging of the winner will use the criteria of the amount of CO2 removed and the amount of sequestration, analysis of the overall removal process, amount of energy needed and the land area required.

Carbon negative solutions can be nature based, direct air capture, ocean based, mineralization or other ideas that sequester carbon dioxide permanently.

The competition will be launched on Earth Day, the 22nd April 2021 and run for 4 years until Earth Day 2025 (XPrize Carbon Removal, 2021).

Tree plantation, , spotted gum. Image by author.

Potential ideas that might be submitted are:

Tree planting. Increasing our forest cover and its potential effect on CO2 capture has been assessed by Bastin, et al., (2019). The authors sought to answer the question of how much land is available for potential tree planting and how much carbon dioxide could be sequestered.

They used remote sensing data from satellites, the European Space Agency’s global landcover model and mathematical models derived from direct measurements of tree cover in protected, relatively unaffected areas, to assess the present forest cover. The United Nations Food and Agriculture Organization FAO definition of forests was used, ie 0.5 hectare in size minimum and at least 10% tree cover.

Using climatic, edaphic (soil) and topographic variables which determine the natural spread of forests and woodlands, terrestrial land that could support forests was determined, that is outside of urban areas and croplands, this totaled 0.9 Billion hectares as suitable for forest restoration which equates to 205 GtC stored.

50% of this land was found to be in 6 countries, Russia 151 million Hectares, United States 103m Ha, Canada 78.4m Ha, Australia 58m Ha, Brazil 49.7m Ha, and China 40.2m Ha.

Tree growth was accurately predicted under the present climatic conditions but potential forest cover will decrease by 223m Ha and 46 GtC by 2050 if CO2 continues to rise.

With current anthropogenic atmospheric carbon at around 300GtC, this places restoration of forests, woodlands and their associated ecosystems such as soil carbon, as a most important mitigation solution to the climate crisis.

Organizations like the Half Earth Project Half-Earth Project | E.O. Wilson Biodiversity Foundation (half-earthproject.org) and Rewilding Earth Rewilding Earth Welcome — Home of the Rewilding Institute have important and worthwhile projects, and may be names to watch out for in this competition.

Direct air carbon capture is the process of capturing carbon dioxide from the surrounding air, rather than from a point source such as a chimney. The captured CO2 can then be directed into a stream to be sequestered deep underground or pressurized for further industrial use, eg used to give the fizz in soft drinks.

Several companies are contributing to this technology, for example, Carbon Engineering Carbon Engineering | Direct Air Capture of CO2 | Home, Climeworks Climeworks offers a technology to reverse climate change., and Global Thermostat Global Thermostat.

Direct air capture can be energy intensive, but the required energy of course may be from renewable sources.

Enhanced rock weathering can be used to capture atmospheric CO2 and sequester the carbon by mimicking part of the natural inorganic carbon cycle. Natural long term atmospheric CO2 is regulated by rock weathering and volcanic emissions. Rainwater combines with CO2 to form carbonic acid H2CO3, which can slowly dissolve silicate rocks. The chemical process of weathering silicate rock requires two molecules of CO2 for each molecule of calcium silicate rock CaSiO3.

Land-based enhanced rock weathering for carbon dioxide removal can be done by the application of crushed silicate rocks, such as basalt, to croplands. The basalt then reacts with CO2 in the rhizosphere (root zone) releasing calcium and magnesium ions, resulting in the carbon being sequestered in the soil. Experimental and field evaluation showed four times increase in carbon storage compared to untreated soils (Kelland, et al., 2020).

Widespread mining, crushing to coarse grain and spreading of basalt can be energy and labour intensive.

Tractor with multipurpose spreader. Image — Wikimedia Commons.

Electro-swing activation of electrodes A new approach to CO2 capture | MIT Energy Initiative uses a special class of molecules called quinones and reversing electrical current to attract CO2 and then release it to enable gathering and storage of the CO2.

This process is certainly scalable by producing more units, it can be used for ambient air CO2 or at a point source, and may prove to be low in both energy consumption and cost of fixing atmospheric carbon.

Concrete. The manufacture of cement, which is then mixed with sand and gravel to form concrete, are both processes which are high producers of CO2.

Carbon cure CarbonCure Technologies | Reducing Carbon, One Truck At A Time injects recycled CO2, from industry, into fresh concrete, as it is being mixed, which then becomes Calcium carbonate CaCO3 and stays permanently in the concrete structure.

The widespread use of concrete and the large amount of CO2 generated by its use make a greener concrete option very important.

Concrete truck. Image — Pixabay Creative Commons.

In terms of saving the planet, the Xprize competition over the next 4 years may well be the most important and vital competition in our short human history.

Of course, ‘saving the planet’ is said in anthropogenic terms, the planet and biosphere will still be here long after Mount Rushmore is subducted by tectonic plate movement, and the Earth will be breathing easily for not being under the uncaring foot of mankind. Unless of course we get thinking, and win that prize!


Bastin, J. F., Finegold, Y., Garcia, C., Mollicone, D., Rezende, M., Routh, D., … & Crowther, T. W. (2019). The global tree restoration potential. Science, 365(6448), 76–79.

Kelland, M. E., Wade, P. W., Lewis, A. L., Taylor, L. L., Sarkar, B., Andrews, M. G., … & Beerling, D. J. (2020). Increased yield and CO2 sequestration potential with the C4 cereal Sorghum bicolor cultivated in basaltic rock dust‐amended agricultural soil. Global change biology, 26(6), 3658–3676.

XPrize Carbon Removal (2021) Carbon Removal At Gigaton Scale | XPRIZE Foundation

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Peter Miles

Written by

Peter Miles B.Env.Sc. 45 years in Environmental Science, specializing in Wildlife and Conservation Biology. Writes about Animals, Revegetation & Climate Change.

Age of Awareness

Stories providing creative, innovative, and sustainable changes to the ways we learn

Peter Miles

Written by

Peter Miles B.Env.Sc. 45 years in Environmental Science, specializing in Wildlife and Conservation Biology. Writes about Animals, Revegetation & Climate Change.

Age of Awareness

Stories providing creative, innovative, and sustainable changes to the ways we learn

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