Overview
Orca is a direct air capture (DAC) facility located in Iceland, widely recognized as the largest operational plant of its kind in the world. The facility is operated by Carbon Capture and Storage Ltd. (CCS Ltd.), a joint venture between the Icelandic company Climeworks and the geothermal energy provider Svartengill. Orca began commercial operations in 2021, marking a significant milestone in the deployment of large-scale DAC technology. The plant is situated in the Hellisheiði area, approximately 40 kilometers south of Reykjavík, leveraging Iceland’s abundant geothermal energy resources to power the capture process.
Orca utilizes Climeworks’ proprietary solid sorbent technology to remove carbon dioxide (CO₂) directly from the ambient air. The system consists of large fan arrays that draw in air, passing it over a filter medium containing a potassium hydroxide (KOH) solution. As the air flows through the filter, CO₂ molecules bind to the sorbent. Once the filter is saturated, it is heated to release the captured CO₂, which is then compressed and stored. This process is energy-intensive, requiring both heat and electricity, which Orca sources primarily from the nearby Hellisheiði Geothermal Power Plant.
The captured CO₂ is transported via pipeline to the Carbfix storage site, located about 4 kilometers away. At Carbfix, the CO₂ is mixed with water and injected into basaltic rock formations beneath the Earth’s surface. Through a mineralization process, the CO₂ reacts with the basalt to form stable carbonate minerals, effectively turning the gas into stone within two years. This method provides a permanent solution for carbon storage, reducing the risk of leakage compared to traditional underground reservoirs.
Orca has a current annual capture capacity of approximately 4,000 metric tons of CO₂, with plans for expansion. The facility serves as a proof-of-concept for the scalability of DAC technology, demonstrating the feasibility of combining air capture with geothermal energy and mineral carbonation. Orca’s operations highlight the potential for Iceland’s unique geological and energy landscape to play a pivotal role in global carbon removal efforts, offering a replicable model for other regions with similar resources.
How does direct air capture work at Orca?
The Orca facility utilizes direct air capture (DAC) technology to extract carbon dioxide directly from the ambient atmosphere, rather than from point sources like smokestacks. The process begins with large industrial fans that pull outside air through specialized sorbent filters. These filters contain a solid sorbent material that chemically binds with CO2 molecules, separating them from other atmospheric gases such as nitrogen and oxygen. Once the sorbent is saturated, the filters are heated to release the captured CO2, creating a concentrated stream of gas ready for compression and transport. This thermal swing adsorption process is energy-intensive, relying on heat to reverse the chemical bond and free the carbon dioxide.
Mineralization via Carbfix
After capture, the CO2 is transported to a nearby injection site where the Carbfix mineralization process takes place. Carbfix dissolves the CO2 in water to form a carbonic acid solution, which is then injected into porous basaltic rock formations located approximately 400 to 800 meters underground. The basalt is rich in calcium, magnesium, and iron, which react with the dissolved CO2 to form stable carbonate minerals, effectively turning the gas into solid stone. This mineralization process typically takes less than two years, significantly faster than traditional geological storage, and ensures long-term stability with minimal risk of leakage.
| Step | Process Description | Key Component |
|---|---|---|
| 1. Air Intake | Ambient air is drawn into the system via large fans. | Industrial Fans |
| 2. Sorption | CO2 binds to solid sorbent filters, separating it from other gases. | Sorbent Filters |
| 3. Desorption | Heat is applied to release concentrated CO2 from the sorbent. | Heat Exchangers |
| 4. Compression | CO2 is compressed into a liquid or supercritical state for transport. | Compressors |
| 5. Dissolution | CO2 is mixed with water to form a carbonic acid solution. | Water Mixing Tanks |
| 6. Injection | Solution is injected into porous basalt rock formations. | Injection Wells |
| 7. Mineralization | CO2 reacts with calcium, magnesium, and iron to form solid carbonates. | Basalt Rock |
The chemical reaction for mineralization can be simplified as: CO2+H2O+CaO→CaCO3+H2O. This process ensures that the captured carbon is stored in a stable, solid form, reducing the risk of re-emission into the atmosphere. The entire system is designed to be scalable, with the potential for multiple units to operate in tandem to increase annual capture capacity. The integration of DAC and Carbfix provides a comprehensive solution for removing legacy carbon from the atmosphere, leveraging both advanced filtration technology and natural geological processes.
History and construction
The development of the Orca carbon capture facility represents a collaborative engineering effort between Climeworks and Carbfix, two prominent entities in the direct air capture (DAC) and mineralization sectors. Climeworks, responsible for the atmospheric air capture technology, partnered with Carbfix, which specializes in the mineralization of captured CO2 into stable carbonate minerals. This strategic alliance was crucial for the project's execution, combining Climeworks’ modular capture units with Carbfix’s geological storage infrastructure in Iceland. The construction phase involved the assembly of the capture modules and the integration of the necessary power and heat systems required for the sorbent regeneration process.
Construction and Partnership Dynamics
The construction of Orca was characterized by the integration of modular technology into a semi-industrial scale facility. Climeworks provided the core air capture units, which utilize a proprietary sorbent to pull CO2 directly from the ambient air. These units were housed in a prefabricated structure designed to optimize airflow and thermal efficiency. Carbfix’s role was pivotal in the downstream processing, where the captured CO2 is mixed with water to form carbonic acid, which is then injected into basaltic rock formations. This partnership model allowed for a streamlined construction process, leveraging the strengths of both companies. The facility was built to serve as a proof-of-concept for larger-scale DAC operations, demonstrating the viability of combining air capture with permanent mineral storage.
Inauguration and Financial Overview
The Orca plant was officially inaugurated on 8 September 2021. This date marked a significant milestone in the commercialization of direct air capture technology, signaling the transition from pilot projects to semi-industrial operations. The inauguration ceremony highlighted the collaborative nature of the project and the potential for DAC to contribute to global carbon removal efforts. The financial investment required to bring Orca online was estimated to be between 10 and 15 million. This cost covered the capital expenditure for the capture units, the mineralization infrastructure, and the initial operational setup. The relatively modest investment for a semi-industrial facility underscored the modular and scalable nature of the technology, suggesting that future expansions could be achieved with incremental capital outlays. The successful launch of Orca provided valuable data on operational costs and efficiency, informing the design of subsequent, larger DAC facilities.
Why it matters
The Orca facility represents a pivotal milestone in the deployment of Direct Air Capture (DAC) technology, distinguishing itself as the largest operational DAC plant globally. This status is significant because it transitions carbon removal from pilot-scale experiments to a commercially viable industrial process. The plant’s capacity to extract carbon dioxide directly from the ambient atmosphere provides a tangible benchmark for the global carbon removal market, demonstrating that large-scale negative emissions are technically achievable. By operating at this scale, Orca validates the engineering and economic models that underpin the broader DAC industry, offering critical data on energy consumption, sorbent efficiency, and operational continuity. This real-world performance data is essential for investors and policymakers evaluating the scalability of carbon removal as a climate mitigation strategy.
Integration with Hellisheiði Power Station
A critical factor in Orca’s operational success is its strategic location adjacent to the Hellisheiði Geothermal Power Station in Iceland. This proximity allows the facility to leverage the unique energy mix of the geothermal plant, which provides both the thermal heat and electricity required for the DAC process. The integration reduces the carbon footprint of the capture process itself, as the energy input is largely derived from renewable geothermal sources. This synergy between power generation and carbon capture serves as a model for future DAC facilities, highlighting the importance of co-location with low-carbon energy sources to maximize net carbon removal efficiency. The Hellisheiði site thus functions not just as an energy provider, but as an enabler of the carbon removal value chain.
Impact on the Global Carbon Removal Market
Orca’s operation has catalyzed growth in the global carbon removal market by providing a reference case for other developers. Its success has encouraged further investment in DAC technologies and related infrastructure, contributing to the maturation of carbon credit markets. The facility demonstrates the potential for DAC to complement other removal methods, such as afforestation and bioenergy with carbon capture and storage (BECCS). As the market expands, Orca’s role as a pioneer continues to influence policy frameworks and corporate procurement strategies, reinforcing the viability of direct air capture as a key component of global net-zero pathways. The plant’s ongoing performance data helps refine cost projections and technological expectations for the sector.
What is the carbon offsetting potential of Orca?
The Orca carbon capture plant, operated by Carbon Capture Technology AS, is designed with a nominal annual capacity of 4000 tons of CO2 (per company specifications). This figure represents the maximum theoretical throughput under optimal operating conditions. To contextualize this volume, the operator has compared the 4000-ton annual capture to the emissions of approximately 870 cars (according to Carbon Capture Technology AS). This analogy assumes a standard passenger vehicle emits roughly 4.6 tons of CO2 per year, providing a relatable metric for the public and investors. However, this comparison relies on average driving distances and fuel efficiency, which can vary significantly across different vehicle types and usage patterns.
Actual Capture Rates vs. Electricity Emissions
In May 2025, a report analyzed the actual capture rates of the Orca plant in relation to the electricity emissions generated during its operation (per May 2025 report). The analysis highlighted the energy penalty associated with direct air capture (DAC) technology. The Orca plant uses heat pumps and fans to draw in ambient air, passing it through a filter with a potassium hydroxide solution to absorb CO2. The energy required to power these mechanical and thermal processes results in indirect emissions from the electricity grid.
The May 2025 report indicated that the actual net carbon offsetting potential is influenced by the carbon intensity of the local electricity mix. If the electricity used to run the Orca plant is generated from fossil fuels, a portion of the captured CO2 is effectively "re-emitted" through the power generation process. This creates a net capture rate that is lower than the gross 4000-ton figure. The report emphasized that the efficiency of the offsetting potential is not static; it fluctuates with the grid's decarbonization. As the electricity grid becomes greener, the net benefit of the 4000-ton capacity increases. Conversely, during periods of high fossil fuel dependency in the power sector, the net removal is reduced.
The comparison to 870 cars must therefore be viewed as a gross capture metric rather than a net removal metric. The net removal is calculated by subtracting the upstream emissions from electricity consumption from the gross captured amount. While the 4000-ton capacity remains the operational target, the May 2025 analysis suggests that the real-world climate impact is contingent on the synchronization of the plant's operation with low-carbon energy peaks, such as wind or hydroelectric surges. This dynamic relationship between capture volume and energy source is critical for accurately assessing the plant's contribution to global carbon budgets.
Worked examples
The Orca carbon capture plant in Keflavík, Iceland, operates as a Direct Air Capture (DAC) facility. It removes carbon dioxide from the ambient air and stores it geologically. The process involves air intake, chemical absorption, heating, and mineralization. This section provides worked examples of the plant’s operational parameters.
Example 1: Annual CO2 Removal Capacity
The Orca plant has a designed annual removal capacity. According to Climeworks, the plant can capture up to 400 metric tons of CO2 per year. The calculation is straightforward. The plant operates continuously. The air is drawn through large fans. The CO2 is separated from other gases. The total annual removal is 400 metric tons. This capacity allows Orca to offset the emissions of approximately 85 passenger cars per year, based on average annual emissions. The plant uses modular units. Each unit contributes to the total capacity. The system is scalable. Additional modules can be added to increase the annual removal rate.
Example 2: Energy Consumption and Heat Source
The DAC process requires energy for air movement and heating. The Orca plant uses a mixture of geothermal and solar energy. Geothermal energy provides the primary heat source. The heat is used to release CO2 from the solid sorbent. The temperature required is approximately 100°C to 110°C. This low-temperature heat is ideal for geothermal sources. The solar panels provide electricity for the fans and pumps. The energy consumption is a key operational parameter. The plant consumes about 3.5 MWh of energy per ton of CO2 captured. This figure includes both thermal and electrical energy. The use of renewable energy reduces the carbon footprint of the capture process itself. The geothermal plant Svartsengi supplies the heat. The solar array is located on the roof of the Orca facility.
Example 3: Geological Storage Process
After capture, the CO2 is compressed and transported to the storage site. The storage site is located at the Carbfix facility. The CO2 is mixed with water and injected into basaltic rock formations. The injection depth is approximately 400 to 800 meters. The CO2 reacts with the minerals in the rock. This process is called mineralization. The CO2 turns into solid carbonate minerals. This process takes about two years. The storage is considered permanent. The injected CO2 is stored in the underground basalt. The volume of CO2 stored is equal to the volume captured, minus minor losses. The storage capacity of the site is large. It can store millions of tons of CO2. The injection process is monitored continuously. Pressure sensors and seismic data are used to track the storage.