One of the alternatives found to have promise is the production of biodiesel. Biodiesel is a popular energy alternative with the major oil companies.
Also consider what you need the biodiesel for because this would help you decide where to buy it. Its resources are available in almost all of the countries in the world. Only diesel engines that have natural rubber parts instead of synthetic rubber parts cannot use biodiesel, but these engines are not as common as the engines that can use the biodiesel.
It benefits domestic economies by reducing the dependence on importing foreign petroleum. Water accelerates microbe colonies which shorten the life cycle of the paper filter elements that result in premature failure of the fuel pump. Biodiesel processing is a type of refining and high temperatures are involved so you need to be careful to avoid the risk of serious burns.
There may be some up front investment to buy the processing unit but once you get rolling you will save considerable sums of money over the life your biodiesel processor. You can save money and help to reduce pollution as well.