The first hybrid inland towboat in the United States, the Kirby Green Diamond, will be powered by a Corvus system.

Bergen, Norway and Houston, USA— Corvus Energy is pleased to have supplied the battery energy storage system (ESS) onboard the M/V Green Diamond—the first hybrid diesel-electric inland towboat in the United States, working jointly with vessel owner/operator Kirby Inland Marine, LP, electrical integrator Stewart & Stevenson, and other partners.

Kirby Inland Marine, LP, a subsidiary of Houston-based Kirby Corporation (NYSE:KEX) is the first inland marine transportation company to own and operate a diesel-electric hybrid towboat in the United States, leading the way in reducing inland maritime carbon emissions and enabling Inland Green Corridor operations.

For the Kirby Green Diamond, Corvus Energy supplied a 1,243 kWh Corvus Orca ESS, its market-leading battery ESS that features patented passive single-cell thermal isolation and proven forced-air cooling to deliver the highest standards of safety and performance.

Reducing Emissions, Fuel Use & Maintenance Costs

The Green Diamond design incorporates the ESS to significantly reduce vessel emissions and improve fuel economy. When no shore charging is available, the hybrid towboat will have an estimated 27% reduction in fuel used and CO2 emissions. With shore charging, fuel use will be reduced by almost 80%, resulting in an 88%-95% reduction in emissions of NOx, CO, and HC. Engine run time is estimated to be reduced between 93%-98%, resulting in significantly decreased maintenance costs.

“Corvus, together with our partners, is pleased to be able to provide proven technology to help solve the technical challenges of hybrid vessel propulsion and shore-side charging to accelerate maritime decarbonization,” remarks Ole Jacob Irgens, Corvus Energy – Executive Vice President. “Inland and harbor tugs are ideal candidates for electrification with batteries because their routes are shorter, in proximity to the shore, and have limited power demands. We’re seeing significant interest from tug owner/operators, designers, and builders right now.”

Kirby’s Commitment to Decarbonization

The Green Diamond also represents a strategic step towards Kirby’s commitment to decarbonization, including a 40% reduction of Scope 1 Emissions by 2040. Which, according to the company, represents roughly 160,000 metric tons of CO2 (Source).

“We are pleased to have collaborated with Corvus to make this vessel possible” says Christian O’Neil, President of Kirby Inland Marine. “Kirby is excited to be the first to market with a plug-in hybrid towing vessel. Barge transportation is already the cleanest and greenest form of surface transportation, and we are working to make it cleaner and greener. Our customers who are focused on reducing their emissions want more efficient options. This solution is available today.”

Corvus Energy is pleased to have collaborated with Kirby Inland Marine, LP, Stewart & Stevenson and other partners on the Green Diamond and congratulates Kirby on the vessel christening which occurred last week on August 25, 2023, in Houston, Texas, USA.

Photo caption: The Kirby Inland Marine Green Diamond hybrid diesel-electric inland towboat

About Corvus Energy

Corvus Energy is the leading supplier of energy storage systems (ESS) for maritime, offshore, subsea and port applications. Corvus Energy offers a full portfolio of ESS suitable for almost every vessel type, providing high-power energy storage in the form of modular lithium-ion battery systems. The purpose-built, field-proven battery systems provide sustained power to hybrid and all-electric heavy industrial equipment, including large marine propulsion drives. Corvus Energy has unsurpassed experience from almost 900 projects, totaling over 750 MWh and more than 6 million operating hours. The company also develops maritime hydrogen fuel cells in collaboration with the world leader in fuel cell technology, Toyota.

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