Ethanol can substitute gasoline. Bio-ethanol (produced from biomass) is commonly used in low blends in gasoline, typically 5% (E5) or 10% (E10) on volume basis. Higher blends can be used in flexible fuel vehicles (up to E85), which are currently offered by a wide range of manufacturers.
First-generation bio-ethanol is produced by fermentation of sugars. These sugars can be extracted from feedstocks like sugar beet and sugar cane, or the sugars can be made from starch in crops like wheat or corn. In particular, shipping also offers an opportunity to use cheaper, low-quality biofuels, because marine engines are typically suited to use a low fuel quality (fuel oil). But this opportunity has hardly been applied yet.
