Methanol With Increased Water Content in Internal Combustion Engines

This paper shows the advantages of methanol as a fuel and compares pure methanol (>99.9%) and methanol with a high‐water content (>18%) for use in an internal combustion engine. 18% water content is representative for methanol synthesized from hydrogen and industrial furnace gases as a carbon dioxide source. The achievable best point indicated efficiency is higher than 43% for both fuels. The increased water content of the low‐purity methanol is compensated by a longer injection time and can approximately be compared to a constant exhaust gas recirculation, which cannot be adjusted to the operating condition. Therefore, the best efficiency operation points are limited to a middle engine speed range and high load, which perfectly fits to a serial hybrid powertrain topology (Range Extender). The paper shows that additional energy that may be required for methanol distillation to high purity can be saved without losing combustion efficiency.