An interesting article from Piston Heads explains the effects of Biofuel for the future. All people who have an older car should read this article as the use of 10% of biofuel could harm older engines.
The article in summary:
By 2020 there will have to be 10% Biofuel from renewable sources in fuel for road transport. It has been said that older cars cannot uphold this amount. Most recent cars are able to use the fuel when it reaches a 10% biofuel stage as they have been built to withstand the corrosive effect it has on seals and some alloy components of the cars.
Currently there is up to 5% biofuel in petrol which does not have to be stated under the legislation because the amount is so low it does not have a detrimental effect on the engines. If the amount of biofuel reaches any higher than this, by law there has to be a sign stating: “Not suitable for all vehicles; consult vehicle manufacturer before use”. But by 2013 there has to be 5% biofuel in fuel to be used in road transport. Drivers of older cans that are not able to use the biofuel will have to hunt for regular fuel, which may prove difficult as it will become very rare.
Take a look for the full story: http://www.pistonheads.com/news/