Bio fuels are a viable alternative to fossil fuels. Many varieties exist and they vary significantly. Some examples are that of biodiesel, which entails growing crops that contain high amounts of natural oil then through a process of hydrogenation or refining a more compatible bio diesel, substitute is created. This creates a biodiesel, which can be mixed with mineral diesel then used in any dieselpowered automobile.
There is a similar process that takes place creating biopetrol by fermenting crops such as sugar cane. This creates a natural ethanol, which can also be mixed with petrol to create a sort of hybrid biofuel that can be used in any petrol powered vehicle.
The truth is that bio fuels technology is still young. In the next twenty years, we look set to see biofuel research expand exponentially as we get close to the day when fossil fuels are exhausted.