Brazil's President Inázio Lula da Silva visited Europe not long ago and he promoted the benefits of Brazilian biodiesel in France and Spain. This might have seemed like a good idea, if it weren't for the fact that Spain's biggest oil company, Repsol, had just frozen the construction of a new biodiesel plant alongside the country's largest refinery in Tarragona. This leaves Brazil with just one relatively large oil company, Portugal's Galp, to distribute its biodiesel in the Old Continent.
What is biodiesel? In short, biodiesel is a fuel that's suitable for use in diesel engines that is not based on petroleum. Biodiesel is often made from plant sources. It's also possible to mix biodiesel with petroleum-based diesel fuel in any ratio. Since most any engine designed to run on diesel fuel can use biodiesel, it would seem that this biofuel could displace a great deal of fuel pumped from the ground. In some cases, it is possible to run diesel engines on straight vegetable oil (often r