Seaspan and Maersk have invested $75 million to upgrade 18 chartered containerships, implementing shaft generators, structural modifications, and hydrodynamic improvements to boost fuel efficiency and cargo capacity. This strategic modernization program targets a 10–13% reduction in slot costs while ensuring long-term regulatory compliance and carbon capture readiness.
Singapore | July 8, 2026 – As the containership sector scrambles to manage rising fuel bills and strict carbon emission limits, Seaspan Corporation and liner giant A.P. Moller – Maersk have expanded their long-term partnership with a major fleet modernization program. The program represents a $75 million investment targeted at improving the fuel efficiency, carbon intensity, and carrying capacity of 18 vessels under long-term time charter to Maersk.
The centerpiece of this strategic push is a highly complex, multi-layered retrofit package designed for four 13,000 TEU containerships. Rather than waiting for future fuels to mature, the program relies on immediately deployable mechanical, electrical, and structural upgrades that will improve each ship’s slot cost by an estimated 10% to 13%.
Technical Deep Dive: The 13,000 TEU Retrofit Package
The upgrades represent a masterclass in modern vessel optimization, squeezing extra performance out of the existing hull, machinery, and electrical systems.
| Upgrade Category | Retrofit Measure | Operational & Commercial Benefit |
| Structural Upgrades | Elevated Lashing Bridge | Raises deck securing systems to allow taller container stacks, directly increasing nominal TEU intake. |
| Increased Deadweight Limit (DWT) | Strengthens and recertifies load lines to enhance maximum cargo-carrying weight capacity. | |
| Engineering Upgrades | Shaft Generator Installation | Uses main engine rotation to generate onboard electricity, eliminating auxiliary diesel fuel burn during transit. |
| Main Engine Optimization | Re-tunes injection and turbocharger mapping to maximize thermal efficiency across standard service speeds. | |
| High-Efficiency Propeller & Pre-Swirl Device | Conditions water inflow and reduces drag to lower the propulsion power required to maintain transit speeds. | |
| Carbon Capture Readiness | Pre-allocates deck space, weight margins, and piping interfaces for rapid installation of onboard CO₂ scrubbers. |
1. Shaft Generator Integration (Auxiliary Power Avoidance)
Similar to retrofits targeting auxiliary diesel engines, the installation of a shaft generator allows the main propulsion engine to generate electrical power for the ship’s hotel and reefer loads while underway. Because the massive main engine operates at a far higher thermal efficiency than smaller, high-speed auxiliary gensets, this shift drastically reduces auxiliary fuel burn and overall fuel costs.
2. Hydrodynamic and Propulsion Upgrades
- High-Efficiency Propellers & Pre-Swirl Devices: Installing a hydrodynamically optimized propeller alongside a pre-swirl device (which conditions the water flow before it hits the propeller blades) recovers kinetic energy and minimizes drag, reducing the power needed to maintain transit speeds.
- Main Engine Performance Optimization: Readjusting and tuning fuel injection systems, cylinder pressure parameters, and turbocharger mapping ensures the engine operates at peak thermal efficiency across its entire service speed range.
3. Structural Modification (Increasing Cargo Capacity)
To improve the vessel’s earning potential relative to its emissions output (improving the vessel’s CII rating), the partners are executing physical structural modifications:
- Elevating the Lashing Bridge: Raising the structural bridges where containers are secured allows for taller container stacks on deck, maximizing nominal container intake (TEU).
- Increasing the Deadweight Limit (DWT): Re-calculating and strengthening the load lines where safe and compliant allows the ship to carry more heavy cargo per voyage.
4. Preparing for Carbon Capture (CCS)
Crucially, the vessels are being retrofitted to be carbon capture ready. This means the engineering teams are pre-allocating structural space, deck weight margins, and piping interfaces so that onboard carbon capture and storage (CCS) scrubbers can be installed quickly once regulatory frameworks and CO₂ port reception facilities mature.
Strategic Alignment: Tonnage Provider Meets Global Operator
In a classic “split-incentive” scenario, shipowners are often hesitant to fund retrofits because the charterer reaps the direct benefit of lower fuel bills. However, this joint investment breaks that mold.
For Seaspan (the world’s largest independent container tonnage provider with a massive fleet of 247 vessels), upgrading these ships ensures their long-term asset value remains high as CII and FuelEU standards tighten. For Maersk, the program directly lowers slot costs, curbs fuel burn, and reduces exposure to EU ETS carbon taxation.
The Technology Alliance: WattSpan, Maersk, and COSCO
Adding a technological layer to the announcement, WattSpan, Seaspan’s joint-venture engineering arm—has signed a one-year Memorandum of Cooperation (MoC) with Maersk and China’s COSCO Shipyard.
This framework establishes a formal channel for joint engineering, information sharing, and project execution, ensuring that subsequent retrofit projects can scale rapidly from drawing boards to dry-dock yards.
What the Executives Say
Dimitrios Panagopoulos, Chief Fleet Operations Officer at Seaspan, highlighted the commercial pragmatism of the move “This partnership reflects the kind of practical, high-impact collaboration needed to advance decarbonization across the maritime industry. By working closely with Maersk, WattSpan, and COSCO Shipyard, we are combining technical expertise, operational insight, and long-term investment to improve vessel performance today while preparing our fleet for the fuels and technologies of the future.“
Anda Cristescu, Head of Chartering and Newbuilding at Maersk, added “By working closely with Seaspan, we aim to implement vessel upgrades that reduce fuel costs, lower greenhouse gas emissions, and increase cargo capacity – all of which enhance the competitiveness of our fleet.“
About A.P. Moller – Maersk
A.P. Moller – Maersk is an integrated logistics company working to connect and simplify its customers’ supply chains. As a global leader in shipping and logistics services, the company operates in more than 130 countries and employs approximately 100,000 people.
About Seaspan Corporation Pte. Ltd.
Seaspan Corporation is the world’s leading independent maritime asset owner and operator, focused on long-term, fixed-rate charters to the world’s most prominent container shipping lines. As of March 31, 2026, Seaspan’s operating fleet consisted of 247 vessels, pro forma for undelivered newbuilds (including two Very Large Ethane Carriers and four Open Hatch Gantry Crane vessels ordered in April 2026), representing a total fleet capacity of approximately 2.5 million TEU on a fully delivered basis.
Source: Seaspan Corporation