Originally intended for maritime applications, the Wärtsilä 31, one of the world’s most significant engines, is currently being converted into a clean generator of renewable energy.
With the most power per cylinder for engines of its bore size, this Finnish engineering masterpiece is the most efficient 4-stroke marine engine in its class and now holds the Guinness World Record. It can have eight to sixteen cylinders and produces power output between 4.6 and 10.4 MW between 720 and 750 rpm.
Wärtsilä, renowned for creating some of the world’s largest combustion engines, such as the 89-ft (27-m) tall, 44-ft (13-m) long, 110,000-horsepower RTA96-C, has reimagined the Wärtsilä 31. Though smaller at 15.4 ft (4.7 m) high and 28.8 ft (8.7 m) long, it can still generate up to 13,142 horsepower (9,800 kW) on fossil fuel.
The 31SG-H2 variant, now ready for hydrogen, is a generator that runs on natural gas or a mixture of natural gas and 25% hydrogen. Running entirely on hydrogen is also an upgradeable feature. Furthermore, the 31H2 flexible-fuel type can run on blended fuels or natural gas in addition to fully hydrogen.
If there is enough hydrogen available, these cutting-edge engines have the potential to become the biggest hydrogen-powered generators in the world. Their purpose is to facilitate the operation of a renewable energy-based grid by quickly adapting to intermittent renewable energy sources such as wind and solar power. At the touch of a button, the engines can synchronise with the power grid in only 30 seconds, producing entirely carbon-free electricity with no minimum uptime or downtime.
“We must be realistic about the fact that natural gas will play a part in our power systems for years. Our fuel-flexible engines can use natural gas today to provide flexibility and balance, enabling renewable power to thrive. They can then be converted to run-on hydrogen when it becomes readily available, future-proofing the journey to net zero,” said Anders Lindberg, President of Wärtsilä Energy.
The hydrogen power plant concept, featuring Wärtsilä’s engines, has received phase 1 certification from TÜV SÜD, an organization dedicated to ensuring safety and regulatory compliance. Two more certifications are needed before construction, and hydrogen-ready engines are expected to be delivered by 2026.
Wärtsilä has a track record of reliability that includes more than 1,000 MW of installations and more than a million running hours. Regarding efficiency and long-term economics, the industry is eager to observe how this big machine compares against large fuel cell operations that directly turn hydrogen back into energy and water.
Source: Wärtsilä
