Fuels can be made by fermentation
1) fuels can be made by fermentation of natural products- luckily enough, waste products can often be used.
2) Fermentation is when bacteria or yeast break sugars down by anaerobic respiration.
Ethanol is made by anaerobic fermentation of sugar
1) Yeast make ethanol when they break down glucose by anaerobic respiration.
Glucose --> Ethanol + Carbon Dioxide + Energy
2) Sugar cane juices can be used, or glucose can be derived from maize starch by the action of carbohydrase (an enzyme).
3) The ethanol is distilled to seperate it from the yeast and remaining glucose before it's used.
4) In some countries, e.g. Brazil, cars are adapted to run on a mixture of ethanol and petrol- this is known as 'gasohol'/
Biogas is made…