Alternative fuels must be found for shipping, if global climate protection targets are to be met. The “ShipFC” project, an international consortium of 13 partners coordinated by NCE Maritime Cleantech from Norway, aims to demonstrate that an ammonia-based fuel cell can be used to safely and efficiently propel container ships across long distances. The Fraunhofer Institute for Microengineering and Microsystems (IMM) in Mainz is developing the fuel cell technology.

First the ammonia (NH3) is “cracked” in a fission reactor and split into nitrogen (N2) and hydrogen (H2), which accounts for 75 percent of the gases produced. The N2 and H2 gases are then fed into a fuel cell along with air, which causes the H2 to burn, producing energy plus water. In a second stage of catalytic conversion, the residual gases are purified to generate N2 plus water.

Ammonia has several advantages over hydrogen as an energy carrier: it can be stored and transported in liquid form at just -33 degrees Celsius at standard pressure (or at pressures of +20 degrees Celsius at 9 bar as a gas), while hydrogen has to be stored at -253 degrees Celsius as a liquid (or at pressures of c. 700 bar as a gas). The “Green NH3” for the project will be supplied by YARA, a chemicals giant that can produce it from renewable sources.

The main challenge will be scaling up the technology to achieve an electrical capacity of 2 megawatts – enough to power a container ship. The plan is to produce a prototype by the end of 2022 and to launch it the following year in Viking Energy, a ship owned by the Norwegian company Eidesvik.

Professor Gunther Kolb, director of the energy division at the IMM, has high hopes for NH3: “We see ammonia not as a direct competitor to hydrogen, but rather as an additional option in the area of sustainable energy,” he says in a press release, “Using it in ships is just the beginning.” The EU is providing EUR 10 million in support for the ShipFC project.