We get bio fuels from nature for example: a compost  pit in which we put all the vegetable/fruit waste ,,,or some biodegradable   stuff... like we put all this things with some cow dung or something like that ..we get some fuels ... Now a days as the technology increases ..we humans have made some specific tanks and material to make compost.....a very user friendly manner... they even use some plant oils and some special furnaces ....etc 

Bio - fuels and Bio - diesel's are obtained from nature. Oil extracted from Jatropa seeds can be used to create a clean burning bio fuel that can be used in any diesel engine.