A few points:
- Anyone who can cite an excact percentage of ethanols energy return is most likely lying and have some sort of agenda. The truth is that ethanol can be manufacturered in a number of different ways, using a number of different raw materials, so ethanol does not have an "inherent" energy return.
- Sugar cane is much more efficient than corn. The reason corn is used in the US is mainly because of farmer lobbying efforts. It is not an enviromentally friendly ethanol source. The oil industry is of course using this to slam ethanol as an energy medium/source in general.
- Brazil sells ethanol on the world market for HALF the price of oil. I do not know how much is export subsidies and if they use coal in the production process, but still.
- The energy return of a given ethanol production process is constant (and increasing in general as better processes are invented). The energy return of oil is constantly in decline. The return of energy of ethanol will surpass that of oil, this is certain.
- EU and US subsidizes biomass production anyway. Not using ethanol will not save the energy spent in that production.
- If zero net carbon energy sources are used for ethanol production, ethanol itself becomes zero net carbon. Oil can never acheive this.