What kind of fuel or resources are used to power most engines in the Star Wars universe? They often reference engines as "reactors". Fusion, fission, something fantasy? Is there a waste product and if so what? Obviously the Death Star reactor generated a lot of waste heat, but what other inputs/outputs were involved?
The only thing I can recall that could be used as fuel is maybe Tibanna Gas. Though Wookieepedia says that Tibanna Gas is used just for weapons.
The engines themselves were mostly Ion Drives.
Ion engines were fueled by power cells, liquid chemical reactants, onboard generators, or virtually any other device capable of providing sufficient power.
The engine utilized internal fusion reactions to produce a stream of highly-charged particles that were forced through the engine's exhaust port at nearly the speed of light. Ion engines were sometimes called ion rockets.
Ion engines were known to emit mildly radioactive byproducts, requiring onboard technicians to wear protective gear.
As far as fuel, mostly it was Hypermatter for capital ships/battle stations.
This included Death Star:
A grant from Republic Sienar Systems was given to the Republic Ministry of Science allowing them to continue research into hypermatter for planetary power, deep space mining, ... Some of this research was later used to refine the plans for Sienar's Expeditionary Battle Planetoid, which evolved into the Death Star project.
However, Hypermatter was not the only fuel: TIE fighters' ion engines "utilized internal fusion reactions to produce a stream of highly-charged particles that were forced through the engine's exhaust port at nearly the speed of light" (Source: Wookieepedia). The fuel for them was "High pressure radioactive gas" (see the tank for it in System Components list)
As far as fuel is concerned, I remember reading the Star Wars Technical Journal many years ago and the diagram for the AT-AT shows the cylinder shaped structure on its underbelly as being a 'Deuterium Tank', or 'Deuterium Slush Tank'. (I can't remember which it was exactly). This would suggest that a basic fusion reactor is the power source for many vehicles and smaller ships, since deuterium is a 'heavy hydrogen' isotope used in (theoretical) fusion production along with Tritium.
In the Clone Wars series, Malastare was shown to be a major exporter of fuel, a green liquid substance, with which the Dugs native to the planet attempted to poison Zillo beast.
Also, in one of the republic commando novels, Kaminoan thousand-year old Jedi Kina Ha and Tallisibeth Enwandung-Esterhazy were hiding in a ship's fuel compartments to escape stormtrooper inspections. I slightly recall that the material in the tanks were described as something similar to liquid metal.
