The latest addition to the Wärtsilä Marine Power engine portfolio, the new Wärtsilä 25 medium-speed four-stroke engine is designed to accelerate and support the maritime sector’s efforts in achieving decarbonized operations.
Based on Wärtsilä’s successful modular technology platform, the engine is already capable of operating on diesel, LNG, or on either gas or liquid carbon-neutral biofuels. According to the company, it can easily be upgraded to operate with future carbon-free fuels as they become available, with the flexibility of having different valve timing options being a key enabler for future fuels and emissions optimization.
The Wärtsilä 25 is intended to be the first Wärtsilä engine to run on ammonia as a fuel – technology development is currently underway with a technology concept readiness slated for 2023, followed by planned product release soon thereafter.
CHECKS ALL THE BOXES
“This engine marks the beginning of a new era of future-proof medium speed, small-bore engines, and comes as an important step towards the maritime industry meeting its decarbonization goals,” says Roger Holm, president marine power and executive vice president at Wärtsilä Corporation. “The Wärtsilä 25 checks all the boxes. It is a small but powerful engine, and it provides an effortless transition to future fuels, making it a future-proof investment already today. Most importantly, the Wärtsilä 25 brings all of these advantages while keeping the total cost of ownership within reason.”
When operating with natural gas the engine is IMO Tier III compliant, as it also is with diesel when integrated with a Wärtsilä NOx Reducer (NOR) emissions abatement system. Additionally, it enables economically viable compliance with regulations such as the IMO’s CII and EEXI protocols that enter into force in 2023.
The Wärtsilä 25 is designed for long periods of maintenance-free operation and it supports dry-docking 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.
The new medium speed four stroke engine features a robust and highly efficient turbocharging system with a high pressure ratio. It is now available in 6L, 7L, 8L and 9L cylinder configurations. The dual-fuel (DF) version 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 optimizes combustion and the fuel-injection settings at all loads. This in turn promotes smoke-free operation.
Other features include a self-learning proportional, integral, derivative (PID) control to reduce calibration needs, and the gathering of critical engine data for predictive maintenance, reporting and analysis purposes via Wärtsilä’s Expert Insight service. The modules can be replaced “on the fly,” which eliminates 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.