DNV has verified that Carbon Ridge’s centrifugal onboard carbon capture system achieved a peak CO2 capture rate of 98% during a five-month pilot aboard Scorpio Tankers’ LR2 vessel STI Spiga. The trial marks the first successful maritime deployment of centrifugal OCCS technology, offering shipowners a highly compact, column-free retrofitting solution to meet strict global emission mandates.
Athens and Santa Monica | June 3, 2026 – The commercial viability of Onboard Carbon Capture and Storage (OCCS) took a significant leap forward as global classification society DNV independently verified the performance metrics of Carbon Ridge’s centrifugal carbon capture technology.
Following a rigorous, five-month real-world pilot project aboard an LR2 product tanker owned by Scorpio Tankers Inc., the technical assessment confirmed that the system achieved peak CO2 capture rates of up to 98%.
The evaluation was conducted under DNV‘s newly implemented Recommended Practice for performance verification of OCCS systems. This milestone represents the maritime industry’s first independent performance verification of a centrifugal-based carbon capture system operating under real-world commercial conditions at sea.
The Pilot Framework: Testing on the ‘STI Spiga’
The pilot system was retrofitted in July 2025 during a scheduled drydocking period at the Besiktas Shipyard in Turkey aboard the STI Spiga, a 109,999 dwt, 2015-built LR2 product tanker. Nicknamed the “Lone Ranger,” the modular, containerized system was positioned aft of the vessel’s accommodation block and configured to intercept and treat a portion of the main exhaust gas stream.
Following the shipyard deployment, the system underwent five months of intensive data gathering while the STI Spiga executed its standard global commercial trading routes. DNV’s maritime emissions team subsequently audited the raw operational data, methodologies, and mass-balance calculations.
Pilot Testing & Performance Summary
- Host Vessel: STI Spiga (109,999 dwt / Built 2015)
- Operator: Scorpio Tankers Inc.
- Installation Timeline: Commenced July 2025 (Besiktas Shipyard, Turkey)
- Testing Duration: 5 Months under normal commercial operations
- Peak CO2 Capture Rate: 98%
- Data Consistency: 55% of all recorded observations fell within a high-efficiency band of 86% to 98%
Technical Edge: The Centrifugal Footprint Advantage
Conventional land-based carbon capture systems rely on massive vertical absorption columns that use gravity to trickle chemical solvents through exhaust gas. When adapted to vessels, these columns present severe engineering challenges, including extreme height requirements, stability risks due to ship motion, and massive structural weight penalties.
Carbon Ridge addresses these constraints by replacing static columns with a proprietary centrifugal amine capture technology. By mechanically spinning the exhaust gas through the chemical solvent, the system dramatically intensifies the mass-transfer process.
System Profile & Multi-Pollutant Abatement
| Parameter | Performance Profile | Engineering Context |
| Physical Footprint | Up to 75% reduction in equipment size and volume compared to standard columns. | Fits neatly into a modular, containerized footprint; can be installed vertically or horizontally. |
| Fuel Compatibility | Fuel-Agnostic | Compatible with conventional heavy fuel oils (HFO), distillates, and biofuels. |
| CO2 Abatement (System Target) | 90%+ lifetime reduction capability | Captured gas is compressed, liquefied, and safely stored in specialized onboard tanks. |
| Criteria Pollutant Removal | >99% elimination of PM, NOx, and SOx | Acts as a comprehensive exhaust cleaning system alongside carbon capture. |
Executive Perspectives: Transitioning to Continuous Assurance
The successful trial establishes a precedent for shipowners looking to shield legacy, fossil-fueled hulls from escalating carbon taxation, such as the EU Emissions Trading System (ETS) and upcoming global market-based measures from the IMO.
The Classification View
“Independently verified carbon capture rates will be vital to building out a commercially viable business model for OCCS. At DNV we are applying our new OCCS verification Recommended Practice to make sure performance reporting can be accurately and consistently applied across the industry and to help OCCS scale. This has been a great cooperation with Scorpio Tankers and Carbon Ridge, and we look forward to taking the next steps, moving from periodic verification to continuous assurance by using real-time data.” said, Chara Georgopoulou, Head of Onboard Carbon Capture, DNV Maritime
The Operator View
“We’re pleased that DNV has validated the results of our trial with Carbon Ridge. For any shipowner that foresees higher prices or stricter regulations for carbon, Carbon Ridge’s OCCS is an attractive solution. Their system is both straightforward to install and places a low operational burden on the crew. Carbon Ridge has demonstrated the technical capability and understanding required for marine deployment, and we look forward to building on this partnership.” said, Cameron Mackey, COO, Scorpio Tankers Inc.
The Developer View
“This evaluation under DNV’s Recommended Practice validates the capability of Carbon Ridge’s modular centrifugal OCCS technology to significantly reduce the emissions of existing and newbuild vessels. The initial data and learnings from the STI Spiga trial further underpin our ambitions to scale Carbon Ridge’s OCCS across the global fleet.” said, Chase Dwyer, CEO & Founder, Carbon Ridge
The Bunker Insight
The validation of Carbon Ridge’s 98% peak capture rate alters the economics of the maritime energy transition. Up until now, the industry has focused heavily on shifting to unscaled, expensive alternative fuels like green methanol or ammonia to achieve compliance.
By demonstrating that a compact, centrifugal OCCS unit can perform reliably during active sea voyages without disrupting the crew or ship operations, Carbon Ridge and Scorpio Tankers have shown that conventional drop-in fossil fuels, combined with carbon capture, remain a highly competitive decarbonization pathway.
For the bunker industry, a scalable OCCS market means conventional high-sulfur and low-sulfur fuel oils will retain long-term commercial utility, provided an end-to-end CO2 discharge and utilization infrastructure is established at major global ports.
About Carbon Ridge
Carbon Ridge is a U.S.-based clean technology company specializing in onboard carbon capture and storage (OCCS) for the maritime industry. Headquartered in Santa Monica, California, with operations in Houston, Texas, the company offers a modular, scalable, and fuel-agnostic carbon capture system tailored to the unique demands of shipping. Carbon Ridge also delivers end-to-end CO₂ management, from onboard capture to sequestration and credit generation, creating a comprehensive platform for maritime decarbonization.
Source: Carbon Ridge