Wattlab launches WEstack: a standardised battery system for inland shipping in International Shipping News 03/06/2026 Rotterdam-based technology company Wattlab introduces WEstack: a standardised battery system for inland shipping that can be installed on board within a single working day. With the introduction of WEstack, Wattlab aims to remove one of the key barriers to decarbonisation in the sector: the high cost and long installation times associated with traditional marine battery systems. Where existing systems are often fully customised and require weeks of installation work, WEstack is fully assembled and tested in Wattlab’s workshop. Once delivered on board, the system only needs to be connected. This reduces installation time from several weeks to just one day. According to Wattlab, this represents a major opportunity for inland shipping. “Generators on vessels operate most of the time at only 10 to 15 percent of their capacity,” says Bo Salet, founder and CEO of Wattlab. “That is extremely inefficient. At low loads, a generator consumes relatively large amounts of fuel. By adding a battery pack, the generator can charge the battery at its optimal operating point, after which the battery supplies power to the vessel.” Diesel generators: up to 90% fewer operating hours WEstack is designed to reduce generator running hours by as much as 80 to 90 percent. According to Wattlab, this results in significant fuel savings, lower maintenance costs, and a substantial reduction in CO₂ emissions. In addition, the system improves onboard comfort by reducing noise, vibrations, and exhaust fumes, while also reducing dependence on shore power. The battery system is available in four standard capacities: 100, 200, 300, and 400 kWh. This standardisation enables faster production and installation while keeping costs lower than those of traditional custom-built systems. WEstack is installed on the aft deck of the vessel and is designed for both newbuild and retrofit projects.