A possible change to how engines and alternators work

Game Talk The Drawing Board
1

I guess this is more of a question-suggestion then just a suggestion, pertaining to how engines and alternators currently work. Are they fine as is? If not, I have an idea. Is it an idea you agree with, or would you do it differently?

Currently, engines produce one set movement-power (I’ll call it HP), and use some power (battery power), and use a set amount of fuel. There’s variations on this, of course.

Currently, alternators debuff a set amount of power to the entire vehicle frame (not just the engine it’s connected to, unless I’m wrong here), and produce a set power to the batteries. They do this as long as the engine it’s connected to is on and active. (and in the case of foot pedals, in use.)

I suggest for engines, they be listed as having a range of fuel usage, and that they use fuel based on how heavy they’re being utilized. Their HP would also be a max estimate, and would have a cruise HP estimate as well. All engines would have a ‘cruise speed’ at which they’re producing the most efficient fuel for HP ratio. Below this, they’d be underproducing HP per low fuel and above this they’d be producing a lot of hp for a lot of fuel. (relatively speaking)

Foot pedals would use metabolism instead of fuel and strength instead of HP, but would work similarly otherwise.

I suggest for alternators that they care about how much HP is being produced, and that they are specific to the frame they’re on instead of being vehicle-wide. Instead of a set amount of power they decrease the engines by, they ‘eat’ HP from the specific engine they’re attached to as it runs into a capacitor during a turn grouping, and generates power from eating the HP by dumping the capacitor, with a minimum threshold based on the alternator. Motorbike alternators would have a really low threshold, so they’d be good for foot pedals and 1 cylinder engines, but they would have a really small capacitor, whereas a truck alternator would only be good for v6 and v8 engines because it would have a relatively high threshold but also a large capacitor. Higher capacitor means more energy generated on average per time unit grouping, provided an effluence of HP.
Any HP left over from being eaten by the capacitor during a time grouping would be used to provide movement power to the frame.

2

Changing ‘fuel consumption to power generated’ curve sounds good to me.
Currently the only reasons to use a smaller engine are weight and minimal power consumption, neither of which is really noticeable unless you are actually measuring the changes.
Having an optimal range would make small engines more efficient at low speeds, unless the vehicle itself was really heavy or unaerodynamic. Then we could change the ‘safe speed vs. unsafe speed’ mechanic into ‘low efficiency vs. optimal efficiency vs. overload’.

I don’t really understand what does that whole alternator/capacitor part mean.
Tying alternator load to engine (rather than the entire vehicle) makes sense if the engine is to have non-linear power curve.
What does the threshold mean here? Cutoff below which the alternator doesn’t activate? Would it be based on power utilized or something else (say, vehicle’s current speed)?
By capacitor size, do you mean an upper limit of power produced per turn?

I don’t really see a reason for having alternator threshold. I’d rather have it just eat so much power that you’d always want to pick the optimal one.

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Something like that. I was just trying to use non-engineering guff to come up with some way to make alternators not “Is engine on? Ok generate x power to battery” devices.

Ideally foot pedals and small engines would work on motorbike alternators but the engine would have to try so hard to generate the HP to turn over the bigger alternators that it’d be wasteful, while putting a motorcycle alternator on a v8 engine would be inefficient because it’d be producing too little power for the HP consumed.

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The next step up in realism for alternators is to determine the load on the power circuit. In general things consuming power are going to increase load (engines, AC, lights, battery chargers), and the mechanical drag that alternators cause is going to be based on that load. If you’re getting fancy, load exceeding power is going to make batteries flip from consuming power to supplying power. If you have a really small car you can see this in action, idle the car and toggle the headlights, with a small enough car you can hear the engine load change.
Alternators would have a “base drag” and increasing drag with electrical load. Larger alternators would generally have higher base drag, but they would increase with load more slowly, and have a higher max load, so a large alternator with 2x the max load of a smaller alternator would generally be more efficient than 2x of the smaller alternators at high load, but less efficient at low load, so you’d want to match the alternator to the typical load of the system. With normal vehicles though it shouldn’t matter.
Having said all that though, I think making it that complicated would be hardly noticeable, so it’s not a high priority for me. Much higher priority is modelling traction and torque better, that would be very noticeable. I think that would do what you want WRT “power curve”.