Carbon Dioxide Removal (CDR)

The first major plant for the commercial filtration of CO2 from the air went into operation in Switzerland in 2017 and has a nominal filtration capacity of 900 tons of CO2 per year. The nominal capacity of the plant built in 2021 is 4,000 tons, more than four times that amount.
CO2 Removal as a Service
Founded in 2009, Climeworks developed a technology to filter CO2 from the air. In 2014, a modular CO2 collector was designed and in 2017, the first commercial plant was commissioned in Switzerland. That same year, the Arctic Fox test project began in Iceland, where the filtered CO2 is stored in underground rock strata. As a result of the storage, the CO2 is permanently bound in the form of a carbonate, and the CO2 concentration in the atmosphere decreases.
Corporate Development Focused on DAC+S
In total, more than 15 of the company’s DAC plants have been commissioned. These include both larger plants and smaller demonstration projects. These are divided into two categories: DAC+S and PTX projects.
PTX stands for “Power to X,” the filtered CO2 is recycled back into the circular economy, for example as plant fertilizer, as an additive to mineral water to generate sparkling water, or as a renewable fuel.
In DAC+S (Direct Air Capture + Storage) projects, on the other hand, CO2 is permanently removed from the cycle and stored underground. The focus in research, development and the construction of additional plants lies on DAC+S in order to reduce the CO2 concentration in the atmosphere and to curb climate change.
CO2 Removal as a Service
Founded in 2009, Climeworks developed a technology to filter CO2 from the air. In 2014, a modular CO2 collector was designed and in 2017, the first commercial plant was commissioned in Switzerland. That same year, the Arctic Fox test project began in Iceland, where the filtered CO2 is stored in underground rock strata. As a result of the storage, the CO2 is permanently bound in the form of a carbonate, and the CO2 concentration in the atmosphere decreases.
Corporate Development Focused on DAC+S
In total, more than 15 of the company’s DAC plants have been commissioned. These include both larger plants and smaller demonstration projects. These are divided into two categories: DAC+S and PTX projects.
PTX stands for “Power to X,” the filtered CO2 is recycled back into the circular economy, for example as plant fertilizer, as an additive to mineral water to generate sparkling water, or as a renewable fuel.
In DAC+S (Direct Air Capture + Storage) projects, on the other hand, CO2 is permanently removed from the cycle and stored underground. The focus in research, development and the construction of additional plants lies on DAC+S in order to reduce the CO2 concentration in the atmosphere and to curb climate change.

The first major plant for the commercial filtration of CO2 from the air went into operation in Switzerland in 2017 and has a nominal filtration capacity of 900 tons of CO2 per year. The nominal capacity of the plant built in 2021 is 4,000 tons, more than four times that amount.
“Two conditions are crucial for the successful use of DAC+S technology. The first is the energy source. The plant should be operated exclusively with renewable energy sources to achieve a better carbon footprint. The second is the storage option. Only in an environment with special rock layers does the CO2 trigger a chemical reaction and crystallize into a carbonate. This is why Iceland is such a favorable location. Renewable geothermal energy sources and highly reactive basalt rock layers can be found in the volcanic environment. Another suitable location is Oman, where the technology will be tested with a plant.”
Nathalie Casas
– Head of Technology
at Climeworks
Climeworks Scales Solution to Mitigate Climate Change
In order to increase its own capacity to climate-relevant scales, the company plans to build new plants, establish partnerships with other companies and recruit new employees. At the end of 2021, Climeworks had 160 employees, and this number is expected to increase to between 250 and 300 by the end of 2022. The commissioning of the next largest plant is planned in the next two to three years.
Direct Air Capture and Storage (DAC+S)
Adsorption and Desorption of CO2
The plants consist of metallic boxes in which a filter with a special filter material, the so-called sorbent, is installed. This sorbent contains an amine and has the ability to bind CO2 via adsorption and release it again via desorption. In the adsorption phase, air is blown through the machine by means of a fan and the CO2 is absorbed by the sorbent.
Once the sorbent has reached a high CO2 concentration, the desorption phase begins: the system is closed so that no more air can enter. Excess air in the box is pumped out and the plant is heated. The heat releases the CO2 enriched by the sorbent. The CO2 is then processed in two subsequent steps so that a CO2 purity of over 95 percent is achieved. The CO2 is mixed with water, transported to underground basalt rock layers and permanently stored.

Climeworks holds several patents. These include patents that legally protect the filtration process, the filter material itself, the heat supply process and desorption.

Basalt Rock
Basalt Rock
The basalt rock in Iceland is a highly reactive material. The mixture of CO2 and water triggers a chemical reaction within it. Thanks to the technology of Climeworks’ partner Carbfix, the mixture of CO2 and water crystallizes in basalt rock layers to form a carbonate. The result: the filtered CO2 is stored in the rock and the CO2 concentration in the air is reduced.
Basalt Rock
The basalt rock in Iceland is a highly reactive material. The mixture of CO2 and water triggers a chemical reaction within it. Thanks to the technology of Climeworks’ partner Carbfix, the mixture of CO2 and water crystallizes in basalt rock layers to form a carbonate. The result: the filtered CO2 is stored in the rock and the CO2 concentration in the air is reduced.

Basalt Rock
Partnership with Carbfix in Iceland

In Hellisheidi, hot water and steam are extracted from 50 boreholes and transported via pipes to the geothermal power plant (on the right in the picture).
Filtered CO2 Permanently Stored Underground
Reykjavik Energy operates the geothermal power plant in Hellisheidi, Iceland, where hot water and steam are pumped to the earth’s surface from hundreds of meters below ground. Subsidiary Carbfix returns the water back underground mixed with CO2 that has been filtered out and treated by Climeworks. Carbfix’s technology simulates the natural process of mineralization: The CO2-enriched water is acidic, which triggers a chemical reaction in the basalt rock.
Cations contained in the rocks, such as calcium, magnesium and iron, are released, and mix with the water to form a carbonate. Due to the high density of the CO2-containing mixture compared to the groundwater, the mixture sinks down into the porous rock layers. According to studies by Carbfix, 95 percent of the injected CO2 forms a carbonate after two years.
Filtered CO2 Permanently Stored Underground
Reykjavik Energy operates the geothermal power plant in Hellisheidi, Iceland, where hot water and steam are pumped to the earth’s surface from hundreds of meters below ground. Subsidiary Carbfix returns the water back underground mixed with CO2 that has been filtered out and treated by Climeworks. Carbfix’s technology simulates the natural process of mineralization: The CO2-enriched water is acidic, which triggers a chemical reaction in the basalt rock.
Cations contained in the rocks, such as calcium, magnesium and iron, are released, and mix with the water to form a carbonate. Due to the high density of the CO2-containing mixture compared to the groundwater, the mixture sinks down into the porous rock layers. According to studies by Carbfix, 95 percent of the injected CO2 forms a carbonate after two years.

In Hellisheidi, hot water and steam are extracted from 50 boreholes and transported via pipes to the geothermal power plant (on the right in the picture).

Climeworks obtains the energy to operate the Orca plant from the nearby geothermal power plant in Hellisheidi. The goal is to use only renewable energy sources.
Site Selection Dependent on Energy Sources and Storage Capabilities
Geological storage of CO2 is possible almost anywhere in the world. According to research findings of the Carbon Dioxide Removal Primer, storage capacities are large enough to absorb three times all greenhouse gases emitted since the industrial revolution.
The collaboration with Carbfix and the location of Iceland fulfill important requirements for Climeworks to roll out the technology.
Site Selection Dependent on Energy Sources and Storage Capabilities
Geological storage of CO2 is possible almost anywhere in the world. According to research findings of the Carbon Dioxide Removal Primer, storage capacities are large enough to absorb three times all greenhouse gases emitted since the industrial revolution.
The collaboration with Carbfix and the location of Iceland fulfill important requirements for Climeworks to roll out the technology.

Climeworks obtains the energy to operate the Orca plant from the nearby geothermal power plant in Hellisheidi. The goal is to use only renewable energy sources.
“Iceland is volcanic and the rock is very reactive, which makes it an ideal location. Access to a renewable energy source and reactive rock layers as suitable storage sites for the filtered CO2 are particularly important. The logic behind this is clear: if other energy sources were used, the climate balance of the plants would be much worse. Various locations meet these requirements, and if enough CO2 is to be filtered from the air to limit climate change, the use of the technology cannot be limited to Iceland. There are currently plans to deliver a plant to Oman, which also offers suitable conditions in terms of energy source and storage options.”
Nathalie Casas
– Head of Technology
at Climeworks
Vision: Black Factory

The collectors of the Orca plant differ from those of the Arctic Fox pilot plant. The structure of the collectors, the stability of the hardware and the service life of the filter material used were optimized for plant operation at the Iceland site. The goal is to develop a standardized system for filtering CO2 that can function regardless of harsh environmental conditions.
Findings from Previous Project Arctic Fox Implemented for ORCA
Arctic Fox is the precursor to the largest Orca plant in Iceland to date, with a nominal filtration capacity of 50 tons of CO2 per year. The commissioning of the plant served to test the DAC+S technology in the harsh environmental conditions of Iceland and marked the beginning of the partnership with Carbfix for the underground storage of the filtered CO2. The experience gained from the test project is crucial for the implementation of other projects, explains Nathalie Casas:
Findings from Previous Project Arctic Fox Implemented for ORCA
Arctic Fox is the precursor to the largest Orca plant in Iceland to date, with a nominal filtration capacity of 50 tons of CO2 per year. The commissioning of the plant served to test the DAC+S technology in the harsh environmental conditions of Iceland and marked the beginning of the partnership with Carbfix for the underground storage of the filtered CO2. The experience gained from the test project is crucial for the implementation of other projects, explains Nathalie Casas:

The collectors of the Orca plant differ from those of the Arctic Fox pilot plant. The structure of the collectors, the stability of the hardware and the service life of the filter material used were optimized for plant operation at the Iceland site. The goal is to develop a standardized system for filtering CO2 that can function regardless of harsh environmental conditions.
“The new technology installed in the Orca plant is much more efficient than before, compared to the Arctic Fox project. The structure, the filter material, and the hardware have been optimized and adapted to the climate conditions in Iceland. The air in Iceland, for example, contains a lot of sulfur. Non-ferrous metal components of the silencers at the Arctic Fox plant oxidized within three weeks. Other components, on the other hand, require protection during prolonged snowfall. Findings like these allow for adjustments that reduce risks and vulnerability to failure when building more plants.”
Nathalie Casas
– Head of Technology
at Climeworks

Process data from the Orca plant is collected using sensors. Measurements include temperature, pressure, valve data, quality of treated CO2, weather data, energy consumption and functionality of the sorbent.
Climeworks Focuses on Remote Control and Maintenance
Process control software is used in the Orca plant. Sensors monitor various measured values as well as the condition of the components used. Detailed monitoring enables predictive maintenance. The remote control functionality is to be expanded in the future, explains Nathalie Casas:
Climeworks Focuses on Remote Control and Maintenance
Process control software is used in the Orca plant. Sensors monitor various measured values as well as the condition of the components used. Detailed monitoring enables predictive maintenance. The remote control functionality is to be expanded in the future, explains Nathalie Casas:

Process data from the Orca plant is collected using sensors. Measurements include temperature, pressure, valve data, quality of treated CO2, weather data, energy consumption and functionality of the sorbent.
“The Orca plant is the first of its kind, which is why there are still employees stationed on-site to observe. However, the control is done from Switzerland. The goal is to operate the plants as black factories. This means that there will be no staff on-site and control will be completely remote. For this reason, the OPC UA data communication standard is being tested in laboratory environments. This is to be used for control in the next plant.”
Nathalie Casas
– Head of Technology
at Climeworks
Scaling of the DAC+S Solution
Over the next few years, Climeworks intends to increase the capacity of its plants by a factor of five to ten every two to three years. At the same time, the machine for CO2 filtration will be further optimized, explains Nathalie Casas:
“The development of PTX projects will continue, but plants like Orca are clearly the focus of development work. The machines, plants and process components are designed in a modular way, so that it is easy to replace or insert certain parts, depending on whether or not it is feasible for the particular site. This applies, for example, to modules for heat and energy recovery in the plants’ CO2 collector system.”
Nathalie Casas
– Head of Technology
at Climeworks
Objective: The Mitigation of Climate Change

CO2 Emissions Rise to All-time High in 2021
Which Sectors Generate the Most CO2 Emissions?
The largest share of total emissions is attributable to energy and electricity consumption in buildings (17.5 % of total emissions), industry (24.2 %) and transport (16.2 %). In particular, road transport (11.9 %), private households (10.9 %) and the iron and steel industry (7.2 %) are the main contributors. Energy consumption as a whole accounts for 73.2 % of total emissions. Another notable contributor is the food supply.
Agriculture and forestry account for 18.4 % of total emissions, and animal husbandry for 5.8 %. The food industry, including cultivation and use of land as well as refrigeration, the processing and transport of food, accounts for a total of 26 % of CO2 emissions.
CO2 Emissions Rise to All-time High in 2021
According to a study by the International Energy Agency (IEA), the total amount of CO2 emitted reached a new record high in 2021. With a total of 36.3 gigatons of CO2, emissions in 2021 more than offset the corona-related reduction in emissions in 2020. The trend of rising CO2 emissions will continue.
Energy Emissions Rise Across Virtually All Sectors
With the exception of the transport sector, CO2 emissions from electricity and heating, in industry, and from buildings have increased as a whole in 2020 and 2021. Energy consumption in these sectors accounts for 73 percent of total emissions.
The Use of Fossil Fuels is on the Rise
About 40 percent of global emissions come from burning coal. According to estimates by the Mercator Research Institute on Global Commons and Climate Research (MCC), there are barely 8 years left to curb fossil fuel emissions and limit global warming to 1.5 degrees Celsius.
Which Sectors Generate the Most CO2 Emissions?
The largest share of total emissions is attributable to energy and electricity consumption in buildings (17.5 % of total emissions), industry (24.2 %) and transport (16.2 %). In particular, road transport (11.9 %), private households (10.9 %) and the iron and steel industry (7.2 %) are the main contributors. Energy consumption as a whole accounts for 73.2 % of total emissions. Another notable contributor is the food supply.
Agriculture and forestry account for 18.4 % of total emissions, and animal husbandry for 5.8 %. The food industry, including cultivation and use of land as well as refrigeration, the processing and transport of food, accounts for a total of 26 % of CO2 emissions.
CO2 Emissions Rise to All-time High in 2021
According to a study by the International Energy Agency (IEA), the total amount of CO2 emitted reached a new record high in 2021. With a total of 36.3 gigatons of CO2, emissions in 2021 more than offset the corona-related reduction in emissions in 2020. The trend of rising CO2 emissions will continue.
Energy Emissions Rise Across Virtually All Sectors
With the exception of the transport sector, CO2 emissions from electricity and heating, in industry, and from buildings have increased as a whole in 2020 and 2021. Energy consumption in these sectors accounts for 73 percent of total emissions.
The Use of Fossil Fuels is on the Rise
About 40 percent of global emissions come from burning coal. According to estimates by the Mercator Research Institute on Global Commons and Climate Research (MCC), there are barely 8 years left to curb fossil fuel emissions and limit global warming to 1.5 degrees Celsius.

CO2 Emissions Rise to All-time High in 2021