Feasibility of hydrogen as fuel in medium speed engines

Abstract

This Master’s Thesis consists of a study on hydrogen energy and its possible implementation in medium speed gas engines. The investigation is based on the recent knowledge on hydrogen as an energy carrier. Hydrogen economy, safety and properties in engines are studied as well.

Hydrogen is not an energy source and must be produced from other primary energy sources. Recent production of hydrogen is mostly done using fossil fuels. The infrastructure lacks distribution networks and pressurized or liquid hydrogen storages offer their challenges. So far, applications such as automotive vehicles have been investigated and produced the most.

Advantages along with challenges are faced in hydrogen internal combustion engines. Combustion anomalies such as auto ignition and backfire must be addressed with different avoidance concepts. However, the wide ignition limits with air and low emissions are attractive advantages. Hydrogen and air mixture can be combustible in very lean to very rich mixtures. Exhaust gas consists of NOx emissions and water vapor.

The spark ignited gas engine could be the first priority to be researched. Other potential gas engines are dual fuel, pilot fuel ignited engines. Although dual fuel engines are not studied widely in the literature, the secondary priority could be placed on those engines.

The most important factor with hydrogen fuel is safety. The combustion, pressure, low temperature, hydrogen embrittlement and exposure place many requirements for the environment. Arrangements in power plants can be performed with proper ventilation and grounding of electrical equipment. Ship power has its own challenges due to the lack of space onboard.

Many scenarios can be presented for the implementation of hydrogen energy. European Commission has provided four different hydrogen futures depending on the timeframe.