Hydrocarbon Fuel Cells for 3e

[GURPS Fox]

So, I've been working on a CnC Tiberium/CnC Generals fusion (with some bits from the Earth 21X0 series and Act of Aggression) for a 'remake CnC' setting and one of the things is that most of the petrol/diesel/aviation gas is gone, most of the oil deposits are gone and the majority of the infrastructure for its creation is consumed by a certain von-neumann crystal.

So, GDI is currently using propane/LNG to fuel the engines for its vehicles until proper proton-proton chain fusion reactors get produced in sufficient numbers for mass deployment on vehicles. Using LNG makes things, oddly enough, worse. An LNG-fueled ceramic engine for what is a Humvee requires (for a 10-hour fuel duration) almost 3.5 metric tons of LNG (or 6,814 liters/1800 gallons).

I've checked MA Lloyd's Vehicle Expansion and it makes an LNG-powered fuel cell even worse:

Originally Posted by MA Lloyd's Vehicle Expansion, Chapter 7

*Hydrocarbon Fuel Cells* are fuel cells that consume hydrocarbon fuels and atmospheric oxygen, and exhaust water and carbon dioxide, though there is usually some intermediate chemistry involving catalytic water to convert the hydrocarbon to hydrogen, methane and carbon monoxide. Hydrocarbon fuel cells will run on high grade multi-fuel, but not cheap ones like diesel, or even most standard gasoline or alcohol mixtures. Multiply fuel consumption by 0.8 if using aviation gas, 1.2 if alcohol, 1.5 if propane or hydrazine, 2.0 if methane. The cell can even run on hydrogen, using 1.2 times as much as a hydrogen fuel cell of the same TL.

It is almost like it's forcing you to go fusion as soon as possible and damn the consequences.

From my understanding, RL HC-FCs would be taking a third of the fuel consumption of their standard hydrogen counterparts... not half again. In addition, an HC-FC is 2.375 times heavier than the equivalent supercharged ceramic engine using LNG while having a fraction of the fuel consumption...

If there is a way to make HC-FCs work, I would be glad to hear it.