Fuel to power conversion rates


#1

I think I’ve mentioned this before (on the old forum), but it’s still an issue, so here we go:

The rate at which you can convert fuel (gasoline) into power is pretty ridiculously high (too efficient, that is).
I did a test tonight:
An engine from lawnmower + 3 alternators (bike + car + truck) = 1 liter of gasoline to recharge storage battery (40000 units of power)
(for details https://www.twitch.tv/videos/341444964?t=00h39m30s )
To put it another way: 10L of gasoline = 10 fully charged storage batteries.
And one storage battery can get an electric vehicle MUCH further than 1L of gasoline a vehicle with internal combustion engine.
So not only are you not LOSING of converting fuel into electricity first, you are, in effect, gaining.


#2

It’s a known issue.
I have a solution for it in the works, but it’s currently hung up on the fact that giving vehicles realistic consumption rates drops their range to ridiculously low distances. Still trying to figure out how to resolve that.


#3

Well, the pretty obvious issue is how little locomotive power alternators use up.
A truck alternator uses up 2238 units of power, car alternator 2/3 of that and bike alternator 1/3.
Now, one of the smallest internal combustion engines in the game (you can get from a lawnmower) provides 22380 units of locomotive power.
So ONE engine from a LAWNMOWER(!) can power 10(!!) truck alternators. That’s obviously unreasonable.
Foot pedals provide 23872 units of locomotive power, potentially powering 10+ truck alternators. Again, pure insanity if you ask me.

Now, just add a zero to the end of power requirements of each alternator (without changing anything else about them). Truck alternator at 22380 seems pretty reasonable, being exactly enough to power it with a single lawnmower engine or foot pedals. Or you can hand-crank a single bike alternator with some power to spare. Etc.

Put 7500 watt generator at 60000 power used. At that rate it will be twice more efficient per unit of locomotive power than truck alternator, which is fine for a specialized generator in my book. Well, really, since those things are rare, even higher efficiency would be ok with me for 7500 watt gen.

P.S. As an added benefit, that’s a super-simple PR coding-wise. Just add a zero to 3 values and change the value for 7500 watt gen.


#4

Sorry, no. Real-world alternators actually are 50-75% efficient - they’re small electric motors running in reverse - so consuming 2 kW of motive power to produce 1 kW of electrical power is the correct behavior.

The real issue is that foot cranks produce 25 HP, which is literally 100x as much as they should, and lawnmower engines produce 15 HP, which is 3x to 5x as much as they should. The reason they’re so powerful is that the vehicle speed model depends almost entirely on engine horse power, and almost not at all on vehicle mass, and if you gave them reasonable power values of 150W and 2800W, respectively, then vehicles powered by them would have top speed around 2-5 MPH.

So the fix is redo the vehicle speed model - which I am working on - and then reduce the power of foot cranks and lawnmower engines.


#5

I understand your overall idea, but I fail to see why the current system should not be hotfixed for now while the “new” model is being developed.

I mean, combustion engines only do two things in the game: move vehicles and generate electricity via alternators.

The system has already been “hotfixed” by increasing power output of engines to ridiculous levels to allow them to move vehicles. That brings power generation completely out of balance. It stands to reason we should adjust alternators locomotive power requirements to be in line with actual engine output, no?

I mean, if we simply increase locomotive power requirements of alternators, will something else in the game functionally “break”? What exactly?


#6

He’s not saying it can’t be worked on, but its not what hes working on right now. You can feel free to look into it, but if not please wait for the fix instead of telling the developers how to work.


#7

I just pushed the vehicle speed rework, so I’m not going to write a bandaid that conflicts with that.

A 5 HP lawnmower produces 3.5 kW, it should power a couple of truck alternators. The issue, again, is that we have 15 HP lawnmower engines.


#8

Ok, got it.
It wasn’t exactly clear to me what kind of timescale for the new system was implied.

Also, while we are at it: any plans to introduce conversion coefficient between electric power generation and storage?
I.e. that it would be noticeably less fuel efficient to generate power and store it in batteries than to power equipment on the spot?


#9

Not currently, no.

If you want to provide some references that show how much inefficiency there is in putting power into a lead-acid battery and an Li-Ion battery and then pulling it back out again, I would be willing to add that. But I’m not going to go research it myself.


#10

“An engine from lawnmower + 3 alternators (bike + car + truck) = 1 liter of gasoline to recharge storage battery (40000 units of power)”

Just commenting here, but 1L of gasoline has is roughly 35 MJ of energy, and 1 unit of battery is 1 kJ, so if it weren’t for the 2nd law of thermodynamics, this is what you would expect to happen.

In the really real world, and coming soon to CDDA, the gas engine is maybe 40% efficient, and the generators are around 70% efficient, so you’re looking at more like 4L. And if you want to complain about how that’s not a lot of gasoline to recharge a storage battery… well, there’s many reasons why petroleum is the preferred fuel source of the modern world, but energy density per volume and energy density per mass are two of them.


#11

Speaking in CDDA terms, it’s also a question of how far 1L of gasoline will get a bike with 1L twin gasoline engine over one full storage battery for a bike with medium electrical engine. (1L twin engine has same locomotive power output as medium electrical engine).
I haven’t really tested it, but I think electrical will be able to go much further.


#12

Running the vehicle efficiency test on these two designs:

  {
    "id": "bicycle_test_v2",
    "type": "vehicle",
    "name": "Bicycle",
    "blueprint": [ "o#o" ],
    "parts": [
      { "x": 0, "y": 0, "parts": [ "xlframe_vertical_2", "saddle",  "controls", "engine_vtwin", "alternator_motorbike", "battery_motorbike" ] },
      { "x": 1, "y": 0, "parts": [ "xlframe_vertical", "wheel_bicycle_steerable", { "part": "tank_small", "fuel": "gasoline" } ] },
      { "x": -1, "y": 0, "parts": [ "xlframe_vertical", "wheel_bicycle", "basketsm", { "part": "tank_small", "fuel": "gasoline" } ] }
    ]
  },
  {
    "id": "bicycle_test_e",
    "type": "vehicle",
    "name": "Bicycle",
    "blueprint": [ "o#o" ],
    "parts": [
      { "x": 0, "y": 0, "parts": [ "xlframe_vertical_2", "saddle", "storage_battery", "engine_electric", "controls" ] },
      { "x": 1, "y": 0, "parts": [ "xlframe_vertical", "wheel_bicycle_steerable" ] },
      { "x": -1, "y": 0, "parts": [ "xlframe_vertical", "wheel_bicycle", "basketsm" ] }
    ]
  },

I get the V2 bike will go 132100 tiles on a road at cruise speed without running out of gas, or 68310 over dirt. The electric engine bike will go 100700 tiles on a road at cruise speed without running out of energy, or 8650 over dirt.

Now that’s 4L of gas versus 1 storage battery. It would be fair to quarter the range of the v2 bike to represent 1L of gas, in which case it’s 33025 tiles versus 100700 tiles on a road, or 17075 versus 8650 on dirt. Neither bike has really good off-road capability, but the electric bike pays a huge penalty for having to lug a storage battery off-road and really wrecking its traction numbers.

With the vehicle speed rework, the numbers are 106600 on road for the V2 bike versus 32590 for the electric, and 54770 on dirt for the V2 bike and 2850 for the electric. Again, if you quarter the V2 bike’s values, you’re looking at 26650 versus 32590 for 1L of gas versus 1 storage battery, and that’s possibly generous for the gas bike but in the right ballpark.

So yes, I think currently in CDDA that electric vehicles have too much range and weird power consumption numbers. This is not news. It will be addressed sooner or later.