3.11     evaluate the factors relevant to the choice of method used in the manufacture of ethanol, for example the relative availability of sugar cane and crude oil

Fermentation is a batch process and produces alcohol of low purity up to a maximum of around 15 % concentration. Distillation is needed to obtain a higher concentration of ethanol. However, the sugar cane is a renewable resource and relatively simple plant (equipment) is needed. This method is favoured in less developed countries with access to cheap labour and sugar cane.

The ethene and steam method is a continuous method and can produce large quantities of high purity, up to 100 % concentration. However, the crude oil (source of ethene) is a finite resource, and the plant required is relatively complicated and expensive.