Future of bio-ethanol

The energy yield of bio-ethanol is about one third lower than petrol. One liter of bio-ethanol substitute only about 0.65 liters of petrol. This is due to different caloric values of petrol & ethanol. The energy content of petrol is 32.5MJ/L & 21.2MJ/L of bio-ethanol. In Brazil, all brands of automotive gasoline contain anhydrous ethanol in the range of 20-25% (E20-E25).

For using fuels that are highly blended with bio-ethanol (E20-E100) conventional engines have to be refitted with more efforts. This is due to the characteristic of bio-ethanol to dissolve some rubber and plastic. Recently an increasing number of vehicles are manufactured, which support petrol as well as bio-ethanol. Sensors of these flexible fuel vehicles can automatically detect the types of fuel and adapt engine running.

Fuel cells- although the use of bio-ethanol in fuel is not commercially viable, technical applications of ethanol are possible.

Table 1a - consumption of petrol in India

10000000	Kiloliters
500000	Kiloliters  of 5% ethanol
500000000	Liters of ethanol

Table 1b - Ethanol in India

Ethanol	Lakh Liter
Demand all over country	5000
Existing production	1840
Total demand	2460
Demand in Maharashtra	700

Table 2 - Worldwide production cost of gasoline & bio-ethanol from other sources

FUEL	BIOMASS SOURCES	PRODUCTION COST [€/liter]
Fossil fuel	Gasoline	0.24-0.27
Bio-ethanol	Corn	0.43-0.48
	Sugar cane molasses	0.22-0.29
	Wheat straw	0.43-0.55
	Sweet sorghum	0.21-0.26
	Sugar beet	0.42-0.46
	Lignocelluloses	0.22

Figure 3: CO2 emission from fuels