Full maritime electrification has long been restricted to small harbor tour boats and regional shuttle vessels, but a new milestone in naval architecture has completely shifted those boundaries. Buquebus has officially unveiled the China Zorrilla, a massive 426-foot (130-meter) catamaran equipped with an astonishing battery system reaching up to 43 MWh. Built by the Tasmanian shipyard Incat, this colossal vessel now claims the title of the largest battery-electric vehicle on Earth, operating completely free of fossil fuels during its scheduled river crossings.
Operating across the Río de la Plata between Puerto Madero in Buenos Aires, Argentina, and Colonia del Sacramento, Uruguay, the ferry traverses a 37-mile (60-kilometer) route in approximately 90 minutes. Yet, the core engineering feat extends far beyond silent, zero-emission cruising. The true hurdle occurs dockside, where the vessel must completely replenish its massive power reserves in just 80 minutes-the exact window allotted for passenger disembarking and loading.
Engineering the World’s Largest Electric Vessel
To propel a catamaran carrying up to 2,100 passengers and 225 vehicles, naval architects required an unprecedented energy reservoir. The onboard battery pack weighs roughly 275 metric tons (over 600,000 pounds), establishing the largest energy storage bank ever installed on a commercial ship. This system feeds eight electric motors that deliver a combined 19.2 MW of power, driving advanced waterjet propulsion systems.
The hull itself represents a major manufacturing achievement as the largest aluminum catamaran ever built, spanning 426 feet in length and 105 feet (32 meters) in beam. Because engineers optimized the lightweight aluminum structure strictly for high-frequency short-sea transit rather than rough open-ocean conditions, the vessel was transported from Tasmania aboard the Black Marlin, a semi-submersible heavy-lift ship that completed an epic 9,300-mile (15,000-kilometer) journey to South America.
High-Power Shore Stations: Delivering 15 MW in 80 Minutes
Replenishing a 43 MWh battery in under an hour and a half required high-output landside infrastructure engineered completely from scratch on both sides of the river border. Finnish marine technology firm Wärtsilä designed the rapid-charging architecture to interface directly with regional utility grids: Edesur in Buenos Aires operating at 13.2 kV, and UTE in Colonia delivering power at 31.5 kV.
- Medium-Voltage Intake: Grid electricity feeds directly from regional high-voltage distribution substations.
- Voltage Step-Down: Industrial dry-type transformers convert the supply down to match shipboard charging hardware.
- Rapid Shore Delivery: Custom 15 MW shore chargers transfer high-amperage direct current straight into the ship’s marine battery banks.
Whenever the catamaran docks, the shoreline transformers must ramp from zero to full output in under 80 seconds, sustain peak output for the duration of the stop, and repeat this intensive thermal cycle multiple times every day. Each terminal features specialized equipment to manage these massive energy transfers safely.
Custom Dry-Type Transformers
Standard liquid-cooled transformers rely on mineral oil, which presented unacceptable safety and environmental risks in close proximity to major passenger terminals and fragile river ecosystems. Argentine manufacturer CAT Miron developed custom cast-resin dry transformers at their General Rodríguez facility to eliminate fire and spill hazards entirely.
Each terminal utilizes four 4,820 kVA transformers, combining for nearly 39 MVA across both ports. Encapsulated in protective epoxy resin to guard internal windings against maritime humidity and saline air, the units are split into modular outdoor enclosures designed to fit within strict port boundaries.
Fleet Economics and Environmental Shifts
The introduction of the China Zorrilla substantially transforms travel across the Río de la Plata, a busy corridor serving roughly 2 million travelers annually. By accommodating 2,100 passengers, the new flagship nearly doubles the capacity of the company’s previous vessel, the Francisco, which carries 950 travelers and 135 vehicles.
By replacing two conventional diesel-powered ships on the route, the zero-emission catamaran cuts regional passenger transit emissions by an estimated 84%. The transition also removes underwater engine exhaust, minimizes acoustic disruption for aquatic wildlife, and completely eliminates the risk of fuel spills during bunkering operations.
| Specification | China Zorrilla Metric |
|---|---|
| Battery Capacity | 40 to 43 MWh |
| Battery Pack Weight | Approx. 275 metric tons |
| Total Propulsion Output | 19.2 MW (8 electric motors) |
| Vessel Dimensions | 130 m length / 32 m beam |
| Passenger & Vehicle Capacity | 2,100 passengers / 225 cars |
| Shore Charger Rating | 15 MW (80-minute charge cycle) |
Supported by the World Bank and Banco Santander Uruguay through the world’s first certified maritime “blue finance” framework, the project represents an investment between $170 million and $200 million, including extensive terminal grid upgrades. Originally contracted as an LNG-powered vessel in 2019 before pivoting entirely to battery electrification, this massive aluminum ship proves that zero-emission marine engineering can successfully power high-volume international routes today.
