Hydrocarbon Fuel Cells for 3e

[GURPS Fox]

Originally Posted by Rupert

How about giving them the same weight and price as the VE2 hydrogen fuelled ones, and giving them a multifuel consumption equal to the listed hydrgen consumption times the ratio multifuel to hydrogen given for IC engines (so about 0.02 gph at TL9+). This makes them economical but heavy.

Please note that using gas turbines would balloon my fuel requirements, especially since my setting has ETC guns (firing AP ammunition) as standard.

To give you an idea, I'll give you three different engines using standard vehicle calculations:

• Ceramic Engine (Supercharged, LNG fuel): 4MW output, 88111lbs/3997kg weight, 180gph
• Gas Turbine (standard, LNG Fuel): 4MW output, 4417lbs/2003kg, 330gph
• Hydrocarbon Fuel Cell (LNG Fuel): 4MW, 2025lbs/9083kg, 153gph (/3)/80gph (multifuel modifier)

With a running time of 10 hours being an outright requirement (because, well, a certain von-neumann crystal ate most of the oil fields and associated infrastructure outside of, essentially, those in enemy hands), you can see where this is going.

Note, the current Humvee equiv has an engine grouping (fuel and all) of 22281lbs/6677kg in terms of mass.

Note that there are other options aside from fusion - fission reactors are lighter and cheaper at TL9.

Are they MHD Turbines or something else?

One other thing - do these extra rules use realistic fuel consumptions (VE2X p.23) and thus give consumptions three time higher than VE2 assumes?

MA Lloyd's Vehicle Expansion says this:

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

p82a Realistic Fuel Consumption
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Many fuel consumptions in Vehicles are seriously understated (see p82). Realistically jets use nearly 5 times as much fuel as indicated (1.75 times as much for hydrogen burners). Hydrocarbon-burning internal combustion engines and turbines use about 3 times the stated volumes, hydrogen burners about 1.5 times. Fuel cell and rocket engine consumptions are about correct. The numbers in the additions in this chapter are realistic, if the existing figures in Vehicles are kept, you will need to divide these appropriately and be prepared to veto perpetual motion designs. On the other hand, in some genres fuel rarely runs low - the GM may want to divide power plant and especially reaction engine fuels by a considerable factor in a cinematic game.