The International Maritime Organization (IMO) issued on the 13th of April 2018 a press release titled: “UN body adopts climate change strategy for shipping”. [1] This document illustrates the commitment of the IMO to significantly reduce the emission of greenhouse gasses (GHG) from international shipping in coming decades. However, the question arises whether the ambitious goals, set out in this press release, are feasible to be met.

This aim of this thesis is to investigate the economic and technological feasibility of powering a vessel while emitting minimal greenhouse gasses in 2050. The focus will be on power plant configuration consisting of an energy storage medium and energy converter. A case study, concerning a representative ROPAX ferry built in 2050, is performed to illustrate the feasibility of using such a power plant configuration.

Energy storage media considered are hydrogen, ammonia and batteries. The use of internal combustion engines, fuel cells and an ammonia reformer are also investigated. The performance of power plant configurations with respect to their estimated greenhouse gas emission, overall weight, required volume, initial investment cost and cost of the required energy per day of operation is evaluated and based on the results of this study several conclusions are drawn.

• First and foremost is the need to reduce the price difference of hydrogen and ammonia compared to LNG. Without this reduction, no single synthetic fuel can be considered economically feasible. Three options to reduce the price difference are identified:
- a high LNG price including high emission tax;
- a low commercial electric energy price; or
- synthetic fuel production using excess renewable energy.
Especially the last of these three is considered to be a feasible measure due to the expected presence of excess energy from solar and wind farms.
• The second conclusion is that using fuel cells or batteries are the most environmentally friendly option due to the emission of N2O when using internal combustion engines.
• Thirdly, all sustainable configurations require a considerable amount of space.
• Furthermore, the combination of relative low electrical efficiencies and high hydrogen price result in high daily costs for hydrogen fueled internal combustion engines and PEMFCs.
• The initial investment cost and system weight of batteries-based configurations are high.

Following these conclusions, only three power plant configurations remain. Based on expected safety and logistical concerns and the expected potential for improvements, a single configuration was determined to be the most suitable to be used on a ROPAX ferry in 2050. This power plant configuration is composed of a SOFC directly fueled by ammonia.

After assessing the safety concerns associated with handling ammonia and the implications the established power plant configuration has on the general arrangement of the ship, it is concluded that the use of such a power plant configuration is highly likely to be feasible in 2050. However, it is recommended to perform a more in-depth analysis of required safety measures and operating characteristics of fuel cells in future research.