Two major problems are facing human life on earth namely, environmental pollution and the near future depletion of conventional fuel. Solutions are being sought for these problems.Many techniques are being used successfully to tackle pollution problem such as improving engine design, exhaust gas treatment, looking for non polluting fuels. Also many research are carried out and applied in the area of clean and renewable energy sources. Solar energy, wind energy, geothermal energy, tidal energy…etc.Hydrogen is a non polluting and renewable fuel when used in internal combustion engines. Its combustion products are water and nitrogen oxides. The nitrogen oxides can treated by many available techniques. Hydrogen can be produced from electrolysis of water, metal hydrides, plant crops. However, there are still practical difficulties in using hydrogen purely as a fuel in internal combustion engines. It is simpler to use it blended with other hydrocarbon fuels.This book is an attempt to shedding light on using hydrogen blending technique in compression ignition engines. The book is an M.Sc. thesis prepared at Babylon University in IRAQ.
