Twenty promising climatetech companies were selected to advance to the final stage of a global competition backed by Elon Musk's foundation — and three of the finalists hail from Houston.

Vaulted Deep, Mati Carbon, and Climate Robotics secured finalists spots in XPRIZE's four-year global competition is designed to combat climate change with innovative solutions. XPRIZE Carbon Removal will offer $100 million to innovators who are creating solutions that removes carbon dioxide directly from the atmosphere or the oceans, and then sequester it sustainably.

"For the world to effectively address greenhouse gas emissions, carbon removal is an essential element of the path to Net Zero. There's no way to reverse humanity's impact on the climate without extracting carbon from our atmosphere and oceans," Anousheh Ansari, CEO of XPRIZE, says in a news release. "We need a range of bold, innovative CDR solutions to manage the vast quantities of CO2 released into our environment and impacting our planet.

"The teams that have been competing for this Prize are all part of building a set of robust and effective solutions and our 20 teams advancing to the final stage of XPRIZE Carbon Removal will have an opportunity to demonstrate their potential to have a significant impact on the climate," Ansari continues.

The finalists — categorized into four sections: air, rocks, oceans, and land — were selected based upon their performance in three key areas: operations, sustainability, and cost. The full list of 20 finalists is available online.

Around 20 Houston-area companies were initially identified by the challenge. Here's a look at the three that are advancing to the finals:

• Mati, in the Rocks category, durably removes carbon from the atmosphere using basalt based enhanced rock weathering (ERW) in smallholder rice paddy farms. This process, which is being demonstrated in India, removes atmospheric CO2 while adding key nutrients in the soil helping to restore degraded soils to benefit smallholder farmers.
• Climate Robotics, in the Land category, enables broad-scale agriculture adoption of biochar which builds soil health and removes excess carbon from the atmosphere. The company's mobile technology converts crop residues into durable biochar on the fly and in the field, making the economics work for farmers and our ecosystems.
• Vaulted Deep, also in the Land category, delivers scalable, permanent, carbon removal by geologically sequestering carbon-filled organic wastes. Their patented slurry sequestration, which involves the geological injection of minimally processed wastes for permanent (10,000+ year) carbon removal.

"This cohort of exceptional teams represents a diversity of innovations and solutions across a range of CDR pathways, and shows the significant progress the industry is making in a short period of time," Nikki Batchelor, executive director of XPRIZE Carbon Removal, says in the release. "Over the past three years, this competition has helped accelerate the pace of technology development for a whole new industry of high-potential solutions aimed at reversing climate change."