Since the introduction of schemes to subsidise the manufacture and use of ethanol, many have called into question the economic and green credentials of such ideas. In particular, it’s important to consider the net energy gained from using ethanol rather than oil and whether land is best used to cultivate ethanol rather than food. Let’s try to examine these points further.

On the positive side, we can produce ethanol domestically which reduces our dependence on the Middle East for oil – perhaps an even greater benefit given the recent turmoil throughout the region. This can only be good for countries such as America and the UK who up until now have been at the mercy of the oil cartels which control the supply of oil.

However there are still some difficulties with using ethanol as a fuel. Firstly, by cultivating corn which is used in the production of ethanol, land is diverted away from growing food. This puts pressure on the food supply chain and leads to higher prices in the supermarket. Fortunately, this problem will be alleviated as technology advances and corn is displaced by cellulose based technology.

There are also some issues from an economics viewpoint. Ethanol has only 60% of the energy value of gasoline therefore you need nearly twice as much ethanol to run your car. Ethanol currently costs about $1.40 per gallon to produce, which after adjusting for the lower energy rating would be equal $2.25 per gallon for the equivalent gasoline. Presently, it’s hard for ethanol to compete on price with gasoline but the costs should come down as technology improves.

Finally, possibly the biggest disadvantage of ethanol is that it is difficult to transport as it absorbs water and is extremely corrosive. Car engines can be modified to use it but the existing pipeline used to transport oil would be unable to carry ethanol. This would create an added expense as the existing fuel infrastructure would have to be adapted. For this reason alone, many argue that ethanol will be replaced by an alternative, more practical fuel, such as butanol.