In today's world, there's a lot of need for energy, so considering the crisis of current scenario, we decided to produce energy from water in form of HHO gas (hydrogen hydrogen oxygen gas), this gas is also known as oxy-hydrogen and brown gas, which is obtained by the process of electrolysis. It is actually an electrolysis unit having high grade stainless steel/graphite/semiconductors as electrodes and mixture of water & suitable ionic solution (KOH or NAOH) as electrolyte. We are going to use this gas as a part fuel along with petrol which will improve the combustion efficiency of the IC engine. HHO gas burns clean and has lot more power due to high calorific value, thus increasing the power produced by the engine. And as this gas is produced form water, the emission of hydrocarbons and carbon dioxide is reduced. The outcome of this project is that the mileage of the vehicle is increased and the fuel consumption decreases due to the HHO gas supplied to the engine, which in fact increases the fuel efficiency. In this research we mainly focused on finding an efficient configuration of an ordinary HHO electrolyser that is efficient than an ordinary system. Therefore, such a system will be able to increase the power of a spark ignition (S.I) engine while reducing the air pollution.