Basics

An engine that can essentially run with any fuel you throw at it
For liquid (non diesel) ICE's it is quite easy to swap between gas, and alchohols
Diesel is a bit more tricky (need to look into this)
Gas fuel systems allow diesel and other ICE's to use CNG, and H-CNG, do they work with pure hydrogen gas, or syngas?
Gas turbines tend to be quite fuel agnostic
Solid fuels are also difficult
- Slurry fuels like Charcoal-Water Slurry Fuel can, and have been used, any issues of engine clogging/fuel tank settling, also how to adress this?
- Add on gassifiers can be used to convert nearly any solid fuel to syngas and possible slag/ash
Most ICE/Turbine based systems should change settings via computer modes to best suit the fuel in use (air/oxygen in, fuel dosing etc)
ECE's are much easier to do this with, but efficincy may be less, and they would require the use of some working fluid, but we are developing the Steam Engine so that may work
Also electric vehicles are TECHNICALLY Fuel Agnostic as the electricity can be generated by many methods, but for this concept they will not count

Fuel Agnostic Engine