Biogenic admixture increases the possible savings in carbon dioxide emissions and reduces the dependency on fossil fuels. In this context especially alcohols not only provide the opportunity to optimize the trade-off between nitrogen oxides and particular matter (NOX/PM trade-off) with conventional combustion processes but they can also support alternative combustion processes by their advantageous properties concerning reaction kinetics. At the Institute of Internal Combustion Engines of the TU Braunschweig investigations on a single-cylinder heavy duty research engine regarding FAME/ethanol and butanol admixtures employing conventional and alternative combustion processes were carried out.