The current energy system, based on fossil resources, has led to increased global temperatures, and poor air quality. A new, defossilized, sustainable energy system is needed. This requires replacing the current energy carriers. Future energy systems will be supported by a Power-to-Fuel-to-Power (PtFtP) principle. The main route in such systems is electrification, as it is the most efficient route. However, due to the intermittency of renewable power production the capacity to store the energy for longer periods of time, in the form of an “e-fuel” such as hydrogen or methanol, is necessary. Converting the chemical energy of the fuel back to power can be done efficiently using large internal combustion engines (ICEs). Some e-fuels offer the potential of using new combustion concepts such as spark ignited stratified combustion (SISC), by eliminating some emission formation pathways (e.g. soot). This enables increased efficiencies and near-zero emissions. However, fundamental knowledge about this novel combustion concept is lacking. This research project aims to provide new knowledge so to better understand the parameters affecting SISC ignition and stability. Such improved understanding will advance the research into power production units employing this principle for more robust future PtFtP systems.