Wärtsilä and Furetank crack down on methane slip

Finnish marine technology supplier Wärtsilä and Swedish shipping company Furetank are co-developing and testing two technologies showing the potential to halve the methane slip of LNG-fueled ships.

Methane slip on LNG-powered vessels refers to the unintentional release of methane, a potent greenhouse gas, into the atmosphere during the process of converting LNG into energy.

While LNG is considered a cleaner alternative to traditional fossil fuels, some methane, which is the main component of natural gas, can escape without being fully combusted in the engine. This can occur due to incomplete combustion, leakage in the fuel system, or during startup and shutdown phases when engine efficiency is lower.

As such, methane slip undermines the environmental benefits of using LNG as a marine fuel, as methane has a much higher global warming potential than carbon dioxide over a shorter timescale.

Therefore, efforts to reduce methane slip by improving engine design and optimizing the combustion process are central to improving environmental benefits of LNG-powered ships.

Furetank said that the two technical solutions have been tested in the company’s Vinga series tankers. One of them is a greenhouse gas (GHG) reduction package, developed by Wärtsilä for dual-fuel engines. The GHG package actively controls the engine while working in demanding conditions like manoeuvring, harsh sea conditions or varying fuel quality.

The company said that in this way, combustion is optimized and unburned gas emissions minimized.

The other solution is the low load optimization package, which reduces the methane slip at low engine loads, for example during harbour operations like loading and unloading. This package actively balances the loading of each engine cylinder, optimizing the overall total engine efficiency even at a low engine load.

The tests performed, both in the laboratory and at sea, show very promising results, according to Furetank, which claims that the methane slip was reduced by 45-50%.

“These are great results, far exceeding what we had expected or technically believed. The tests show a significant impact in absolute terms. We believe many shipping companies will be interested in these solutions. And this is not the end of the road, there is more to be done,” says Göran Österdahl, sales director of marine power at Wärtsilä.

For Furetank, this is yet another step in progressing the emission-reducing technology in the Vinga vessel series, designed by Furetank with partners.

“We had many discussions with Wärtsilä during the past years on how to counter the methane slip. It is a tough nut to crack and the most important technical issue for us to solve. There is an ongoing chase for new engine solutions which will only intensify with the EU ETS system and stricter IMO regulations. We are happy to have this fast track to developers and manufacturers of advanced engine technology,” says Clas Gustafsson, Technical Manager at Furetank.

“This is a very successful collaboration, as Furetank has asked us for solutions and offered to perform tests in real-life conditions. We are in a phase of intense research and development on future fuels, making it invaluable for us to find test-willing partners. Our entire industry will need to establish many operator/product developer collaborations. Otherwise, progress will be too slow,” says Österdahl.

The functionality will be implemented in the Vinga sister vessels currently being built at the China Merchants Jinling Shipyard in Yangzhou, and retrofitted into all earlier ships in the series.