At present it is very hard to justify an aggressively pro biofuel policy simply due to high costs for comparatively low benefits.
In order to make biofuels more realistic there are a few things that could happen. Perhaps the main thing would be the complete depletion of the worlds oil reserves. Should this happen then biodiesel and bioethanol will become the only suitable alternative fuel for use in current I.C.E. vehicles. The problem with this scenario is the amount of land that would be required to produce anywhere near the quantities of fuel the UK requires would be quite staggering. By the time this happens it is quite likely that fuel cell technology will have reached a level of maturity whereby it is commercially viable. This is estimated to occur around 2010 to 2015. This would effectively make biofuels obsolete.
As oil reserves do become scarcer then the price of oil will invariably be driven up. Eventually the price of oil will be high enough that biofuels may be able to compete, however this is very difficult to predict for several reasons. As oil becomes scarcer then the price of energy as well as fuel will rise. This may mean that the energy inputs required for biofuel production will become more costly, driving up the price of biofuels.
At present biodiesel produced from waste vegetable oil is commercially viable due to lower duty (20p per litre lower than conventional diesel). The loss in duty associated with this will never amount to too high a value as there is only a limited amount of waste vegetable oil available. Although we feel that biofuel produced directly from agriculture is not worth while, we feel that biodiesel produced from waste vegetable oil is as it has a lower economic cost and produces a useful product from a waste material.