Climeworks Opens "Mammoth II": A Gigaton-Scale Direct Air Capture Facility That Turns CO2 into Solid Rock in Iceland

Healing the Sky

For the last two hundred years, ever since the invention of the steam engine, humanity has been pumping billions of tons of carbon dioxide into the atmosphere. We have wrapped the planet in a thick, invisible blanket of greenhouse gases, trapping the sun's heat and causing the climate to spiral into chaos. We have tried to stop the emissions by building solar panels, wind turbines, and electric cars, but the damage is already done. The blanket is already too thick. To save the planet, we cannot just stop adding to the blanket; we have to take it away. We have to physically remove the carbon dioxide from the air and put it back where it belongs: deep underground. In June 2026, the Swiss climate-tech company Climeworks achieved a monumental milestone in this fight by opening "Mammoth II" in the barren, volcanic landscapes of Iceland. This is not a small experimental pilot plant; it is a massive, industrial-scale "Direct Air Capture" (DAC) facility designed to pull one million tons of CO2 out of the sky every single year. It is the largest carbon vacuum cleaner on Earth, and it is finally turning the tide against climate change.

To understand how Mammoth II works, imagine a giant, industrial box filled with thousands of massive fans. These fans pull in the ambient air from the Icelandic atmosphere. Inside the box, the air passes over a series of specialized, solid-structure filters coated with a proprietary amine-based chemical sponge. This sponge is chemically engineered to have a massive, almost magnetic affinity for CO2 molecules. As the air flows over the filter, the CO2 sticks to the sponge, while the nitrogen, oxygen, and other gases pass right through and are released back into the atmosphere. Once the filter is completely saturated with carbon, the system seals the chamber and applies low-grade heat (around 100°C) to the sponge. The heat breaks the chemical bond, releasing the pure CO2 gas from the sponge, which is then collected in a concentrated stream. The filter is then cooled and ready to capture carbon again. This cycle repeats continuously, 24 hours a day, 365 days a year.

The Geology of Iceland: Turning Gas into Stone

Capturing the carbon is only half the battle; you then have to store it safely for thousands of years. You cannot just pump it into an empty underground cave, because it might leak back out. This is where Iceland's unique geology provides the perfect solution. Iceland is sitting on top of a massive volcanic hotspot, where the bedrock is made of basalt—a reactive, iron-rich volcanic rock. Climeworks mixes the captured CO2 with water and pumps this fizzy, carbonated liquid deep underground, about 1,000 meters down into the basaltic rock formations. When the CO2-rich water touches the basalt, a natural chemical reaction occurs. The calcium and magnesium in the rock dissolve and bind with the CO2, forming solid carbonate minerals. Essentially, the CO2 turns into stone. This mineralization process, which would normally take thousands of years in nature, happens in the basalt in less than two years. The carbon is permanently, safely locked away in the rock, completely immune to leaks, pressure changes, or geological shifts. It is as safe as it can possibly be.

The scale of Mammoth II is staggering. The facility covers an area of several square kilometers, powered entirely by a dedicated, nearby geothermal power plant. Geothermal energy provides the perfect synergy: it provides the continuous, carbon-free heat needed to release the CO2 from the filters, and it provides the electricity to run the massive fans and pumps. The facility operates like a massive, industrial lung, inhaling the polluted sky and exhaling clean air, while simultaneously turning the pollution into solid rock. The cost of capture has finally dropped below $100 per ton, thanks to massive economies of scale and advanced materials, making it economically viable for corporations and governments to purchase "carbon removal credits" to offset their historical emissions.

The Path to a Restored Climate

The opening of Mammoth II is a psychological turning point for the global climate movement. For decades, the narrative has been one of doom and inevitable catastrophe. We were told that we missed the window to prevent warming, and that we just have to adapt to a ruined world. Mammoth II proves that we have the engineering capability to actively reverse the damage. It proves that the atmosphere is not an open sewer that we have permanently ruined, but a massive, manageable system that we can clean up if we apply enough industrial effort. Climeworks has already secured contracts to build ten more Mammoth-scale facilities across the globe, from the deserts of Nevada to the plains of Australia. The goal is to reach one billion tons of capture per year by 2040, effectively neutralizing the remaining hard-to-abate emissions from aviation and heavy industry.

We are standing at the beginning of the "Restoration Era." Just as the industrial revolution built the machines that polluted the sky, the new industrial revolution is building the machines that will clean it. The sight of the massive, white structures of Mammoth II standing against the dark, volcanic backdrop of Iceland is a symbol of human resilience and ingenuity. We broke the planet, but we are not going to let it stay broken. We are pulling the carbon from the air, turning it to stone, and giving the Earth a second chance. The sky is healing, one million tons at a time.