Future fuels development
To power shipping in the future, Wärtsilä is investigating a wide range of fuels, including bio and synthetic liquefied natural gas (LNG) and natural gas along with ammonia, methanol, hydrogen and biofuels. Wärtsilä’s research draws on deep experience gained through decades of building engines as well as supply and storage systems for a wide range of fuels. Wärtsilä is leading the way in developing a wide range of engine and fuel gas supply systems to help ship owners navigate the route to reduced GHG emissions – whatever fuels they choose.
We have today the technology needed to use most future fuels.
Development is on-going for the rest.
Our journey to date: decarbonising shipping
Before we begin discussing future fuels, an important distinction should be made between so-called ‘carbon-neutral’ and ‘zero-emission’ fuels.
- Carbon-neutral fuels are those that have no net carbon emissions, meaning their production and use does not increase the amount of CO2 in the atmosphere. Examples include synthetic fuels made with renewable energy and certain biofuels.
- Zero-carbon fuels release no CO2 when used as they do not contain any carbon. While hydrogen is an example of a zero-carbon fuel, it may or may not be carbon neutral depending on how it was produced.
To power shipping in the future, Wärtsilä is investigating a wide range of fuels.
The exploration of ammonia as a fuel is progressing fast. It has several advantages over hydrogen, for example its greater energy density and the fact that it does not need to be stored under compression or at very low temperatures. But ammonia is toxic and highly corrosive, making it challenging to handle, especially for passenger vessels. Furthermore, the current ammonia supply is fossil based so in future it would have to be made in an environmentally sustainable way as it the case with synthetic ammonia.
Wärtsilä is not starting from scratch in this area. We have several years’ experience of designing cargo-handling systems capable of handling ammonia for use on LPG carriers. On the fuel storage and supply side, we are participating in the EU project ShipFC to develop systems that will supply ammonia to fuel cells that will be installed on Eidesvik Offshore’s supply vessel Viking Energy by 2023. We have performed combustion tests with ammonia in our fuel laboratory, and the next step is full-scale engine tests.
Until now, methanol has not been widely used as a marine fuel. This easily and cheaply produced industrial alcohol is today made predominantly from natural gas, but the use of hydrogen from renewable electricity and recaptured carbon to make green methanol would make it carbon neutral. And with better combustion and easier storage and handling than ammonia, methanol is a key component of decarbonisation in the maritime industry.
Only a few marine engine builders have experience with methanol engines. A project to convert a Wärtsilä Z40 engine on the ro-pax vessel Stena Germanica to burn methanol began in 2015. The engine now runs mainly on methanol, and the success of the installation has inspired Wärtsilä to investigate this fuel further.
The Stena Germanica has been successfully operating with a Wärtsilä engine burning methanol fuel for five years. Copyright: Stena
Fuels derived from biomass have great potential as a carbon-neutral energy source. They can be made in a variety of forms that can be used in both diesel and gas engines, either as a drop-in fuel or as a standalone fuel. As biofuels are compatible with existing engine, fuel supply and storage technologies they could offer simple and capital efficient decarbonisation of shipping.
Wärtsilä has been continuously experimenting with many different biofuels since the 1990s, and over the past ten years has been developing advanced combustion techniques to further improve efficiency and fuel flexibility. More recently, Wärtsilä worked with Boskalis and biofuels company Goodfuels todevelop and test biofuels suitable for use in shipping. We already have several products in our portfolio that can use biodiesel, for example our W20, W31, W32 and W46 diesel and dual-fuel engines.
Wärtsilä already has a strong understanding of hydrogen, and our dual-fuel engines and spark-ignited gas engines can already run on a fuel mix comprising between 15 and 25% hydrogen, further highlighting the flexibility of dual-fuel engines. We first experimented with using hydrogen in our gas engines in 2015 and are continuing development towards a pure hydrogen engine. But fuel storage and supply remain a challenge for hydrogen due to its low volumetric energy density and its explosive and corrosive nature. Synthetic hydrogen will take around a decade to be globally and reliably available; green hydrogen is produced using only renewable energy sources.