1. Gasoline.
2. Diesel.
3. Alcohol
4. LPG.
5. CNG.
6. Electricity.
7. Solar.
8. Producer gas.
9. Hydrogen.

Present Fuels and Limitations:-

There are so many fuels used in I.C. Engines, but they have certain physical and chemical properties. In other words, fuels used in I.C. Engine re designed tom satisfy performance requirements of engine system, in which they are used. The limitations of fuels that are used presently are as follows
1. Gasoline contains many impurities. It has low octane number. All petroleum fuels oxidize slowly in presence of air. The oxidation of unsaturated hydrocarbons result in formation of resinous materials called

gum and reduces its lubricating quality and tends to form sludge and warmish on piston and rings. It has less knock resistance as well as energy per unit mass. It has less efficiency compared to other fuels. It has high cost.
2. In alcohol, higher latent heat of vaporization reduced charge temperatures before combustion. Alcohols suffer disadvantages of water absorption, corrosive and lubricant incompatibility.
3. In LPG, it reduces volumetric efficiency due to its high heat of vaporization. The road sensitivity is very high. It is very corrosive. Response to blending is very poor. It has higher cost of transportation. It has higher cost for conversion kit, installation of extensive.
4. In electricity, they use in initially generated power stations that use fossil fuel of nuclear power. There are other problems too. The problem is with batteries in these vehicles. These batteries are quite heavy and life of these is also low. Cost of replacing these batteries is high.