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Wärtsilä 25 multi-fuel engine launches as company eyes use with ammonia
The engine is intended to be the first Wärtsilä engine to run on ammonia as a fuel, with technology development underway
Finnish technology company Wärtsilä has launched the Wärtsilä 25 medium-speed four-stroke engine.
The modular design of the engine and its valve timing setting options allows it to operate on diesel, LNG, gas or liquid biofuels, and, the company said it can be upgraded to operate with future carbon-free fuels.
"The flexibility of having different valve timing options is a key enabler for future fuels," the company said. "The Wärtsilä 25 is intended to be the first Wärtsilä engine to run on ammonia as a fuel – technology development is currently underway with technology concept readiness slated for 2023, followed by planned product release soon thereafter."
The engine is IMO Tier III-compliant when operating on natural gas alone and can reach compliance operating on diesel fuel when integrated with a NOx emissions abatement system. It also allows for compliance with regulations including IMO’s CII and EEXI protocols that enter into force in 2023, according to Wärtsilä.
"The Wärtsilä 25 is designed for long periods of maintenance-free operation and it supports drydocking schedules with a time-between-overhauls (TBO) of up to 32,000 hours. As a result, both downtime and operating costs are significantly reduced. Data-driven dynamic maintenance planning and predictive maintenance services can extend the TBO even further," Wärtsilä said.
The Wärtsilä 25 engine has a turbocharging system with a high-pressure ratio and is currently available in 6L, 7L, 8L and 9L cylinder configurations. The dual-fuel version of the engine has a power output ranging from 1.9 to 3.1 MW, and the diesel version from 2.0 to 3.4 MW.
The common-rail high-pressure fuel injection technology optimises combustion and the fuel-injection settings at all loads. This in turn promotes smoke-free operation," Wärtsilä said.
The engine also includes a self-learning control to reduce calibration needs and to gather critical engine data for predictive maintenance, reporting and analysis purposes with the use of Wärtsilä’s Expert Insight service.
Wärtsilä said engine modules can be replaced ‘on the fly’, eliminating the need for separate software downloads. Optional and easy-to-apply adjustments for Arctic or tropical conditions and for reducing emissions to the level of a pure gas engine are also available, the company said.
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