$50 million XPRIZE winner wants to help smallholder farmers

Key Points:

– A unique method will capture millions of tons of CO2.
– Startups focusing on geological storage of organic waste and biochar were also recognized.
– The XPRIZE Carbon Removal was created in 2021 with $100 million funded by Elon Musk’s foundation.

In a recent announcement, the organizers of the XPRIZE Carbon Removal competition revealed that a strategy to compensate millions of small-scale farmers in developing nations for reducing carbon dioxide has emerged as the winner. Mati Carbon, the startup behind this concept, secured the top prize of $50 million. The majority of the remaining $100 million prize pool, funded by Elon Musk’s philanthropic foundation, was shared among three runner-up startups.

Mati stood out by introducing an innovative approach to enhanced rock weathering (ERW), a concept that has gained prominence in recent years. Similar to other ERW companies, Mati captures CO2 from the air by crushing basalt rock, which is widely available, and spreading it on farmlands. The rock powder reacts with CO2 dissolved in rainwater, storing the greenhouse gas in a relatively inert molecule called bicarbonate. Additionally, the basalt releases minerals that enrich the soil.

What sets Mati apart is its focus on engaging millions of small-scale farmers, initially those cultivating rice fields in India. The company targets this location due to the favorable wet and hot conditions that accelerate the absorption of dissolved CO2. Mati’s chief science officer, Jake Jordan, emphasized the significance of heat and water flux in speeding up the dissolution process.

Despite the potential benefits of rock weathering, the accuracy of estimates on its carbon capture capacity has been questioned. The variability in factors like temperature on open farmlands poses a challenge for companies like Mati to control the performance of crushed basalt. As a result, early-stage ERW companies are under pressure to conduct thorough sampling and modeling to gain investor confidence.

Mati validated its model by following methodologies from respected standard setters like Puro.earth and Isometric. The startup collected 30,000 samples over four years to study potential rice fields in India and other regions. CEO Shantanu Agarwal expressed confidence in the model’s reliability, stating that it has been consistently proven effective.

Several companies, including Stripe, Shopify, Siemens, and Figma, have already purchased carbon credits generated by Mati. These credits are currently priced at around $300 per ton of CO2 removed, a figure higher than those from reforestation but lower than some alternative removal methods like direct air capture. Mati aims to reduce the cost to approximately $100 per ton as it scales up operations.

Mati operates as a non-profit but plans to expand by partnering with local for-profit entities to manage on-ground activities. Agarwal estimated that a typical smallholder farmer in India could earn an additional $400 from credit sales and soil fertility improvements facilitated by basalt powder.

In addition to Mati, the other top three contenders from the XPRIZE Carbon Removal competition received cash awards:

– Runner-up NetZero secured $15 million for its biochar initiatives in Brazil.
– Vaulted Deep, which manages organic waste disposal by injecting it into geological storage locations, earned the third prize of $8 million.
– ERW startup UNDO, operating in Scotland and Canada, received $5 million.

Significant changes have occurred since the competition’s inception in 2021, with a surge in startups and increased involvement from major buyers like Microsoft and the Frontier coalition. The actions and evolving positions of Elon Musk, the prize funder, have also played a role in shaping the field’s growth. The prize’s executive director, Nikki Batchelor, emphasized the importance of maintaining clear boundaries between sponsors and prize operations, ensuring sponsors have no influence over the selection of winners.