I have a world where there are no fossil fuel deposits. This means that biofuels - fuels artificially created out of biological matter, rather than via geological processes - are the sole hydrocarbons in this world, taking the place of substances such as coal, oil, natural gas, and the like.
Let's say that there's a nation within this world which wants to back its currency with its biofuel reserves. Is backing up a currency with biofuels a viable, functional alternative to backing a currency with things such as gold or governmental promises?
When answering, please take the following into account:
Provided that you have a biosphere (which, hopefully, you do), the supply never runs out; overuse might lead to a dip in reserves, but, provided that you have arable land, you can always grow more plants to turn into fuel. This means that biofuels are constantly created, unlike fossil fuels, which form on geological timescales and therefore will functionally run out eventually. As such, currencies backed by biofuels are more stable than currencies backed by fossil fuels because fossil fuels will never run out (at least, provided that civilization doesn't collapse, but in that case you have bigger things to worry about).
Biofuels are always being consumed, at least as long as the demand exists to do so. After all, they're constantly burnt, vaporized, and released into the atmosphere.
Biofuels are semi-independent of geography, in that they can be produced in any place capable of growing crops. Fossil fuels, on the other hand, are only found in certain places. You cannot "grow" crude oil in, say Hawaii, or "grow" gold in Florida, but you can grow sugar cane in those places and turn that into biodiesel.