Fuel balancing

Recent work in experimental has moved much of the vehicle engine code to JSON. For example it should be possible to define a scotch engine running on whiskey or in the near future a steam engine. One critical change is that fuel consumption is now configurable and will probably need balancing.

For those of you wishing to experiment the magic values are in data/json/items/fuel.json, specifically the energy field for gasoline and diesel. To decrease fuel consumption you should bump the energy value. I’d like to collect player feedback about what those values should be. The aim is to balance around normal vehicle usage although we might also consider a setting for megavehicles.

If you adjust the value please post it here along with what vehicle you were driving and what the fuel economy was like. Alternatively if you don’t adjust the value a concise reply about whether the value should be higher or lower along with what vehicle you used would be reasonable. Shorter posts are appreciated as long opinion pieces aren’t likely to contain significantly more empiric data vs the higher word count.

My initial idea:

[ul][li]An unloaded car brand car with a full tank should be able to cross width of height of 1 overmap when driving on grass, roughly twice that much if on road, when driving at optimal velocity[/li]
[li]An electric car should be able to cross 1/3 of that on 2 full batteries[/li][/ul]

fuel is about the least problematic part of getting and maintaining a car so i dont have an input but to say that its common and never a limitation. even to swap out engines on a humvee to use gas.

[quote=“Coolthulhu, post:2, topic:12965”]An electric car should be able to cross 1/3 of that on 2 full batteries[/quote]Isn’t that way too punishing? or are you talking car batteries and not storage batteries?

Doesn’t seem too punishing to me. Your trading maximum trip distance, with infinite potential distance. Slap some solar panels on, and you’ll get anywhere you want, eventually.

Doesn’t seem too punishing to me. Your trading maximum trip distance, with infinite potential distance. Slap some solar panels on, and you’ll get anywhere you want, eventually.[/quote]You’re also taking the largest possible electric container for it, while the gas one is taking something more sized for a car. if a simple electric car can’t even do a trip between ‘cities’ on two of the largest possible containers and being as efficient as possible, and may not even be able to cross a large city, then what does that mean for anything bigger? cross country movement?

You can make up for that by having bigger containers like you can with fuel, but then it’s a question on how long that’d take to fill, particularly on regular solar panels instead of quantum ones.

There’s also the fact that you can get infinite diesel, it’s not currently all that mobile and requires more time, but the skill requirement is much lower and the deathmobile wouldn’t be riddled with fragile, annoying-to-replace parts.

Gentle reminder that the plan is to obtain usable numbers for fuel efficiency. Electrical power balance for motors and batteries are an important but separate issue.

running a generator , to recharge anything seems not viable anymore, they just run all my fuel dry before i can recharge even the smallest of batteries…
I had a V-twin engine in my mobile base that run car, moto and truck alternators, just for recharging… since the update i thought that it somehow took into account the vehicle weight even if i wasn’t accelerating it to anywhere, so i transfered the generator module to a new light frame with the new motorbike engine 0,4l and also tried to use a Wankel one with same results… fuel goes bye bye too fast!
what am i doing wrong? any suggestions?

X-post to the issue: https://github.com/CleverRaven/Cataclysm-DDA/issues/19348

We figured out on IRC that if you go to /data/json/item/vehicles/engine.json and change lines 18 and 34 to make it read:

“efficiency”: 50,

For the first one, and 70 for the latter, makes it have more consumption than we used to, but still feels good.

60 and 80 is about what we had, maybe a bit more consumption.

Alternators could be out of balance now, will investigate.

Plan is to adjust fuel energy density and not efficiency as the latter would prevent implementation of near-future more efficient engine designs or such items and the electric engines already have an upper bound of 100%

Awesome, IRC user Aabbcc was able to put it all into a mod, and in addition, he managed to fix the battery consumption as well. Thanks Aabbcc!

https://drive.google.com/file/d/0B0btuC1DG_yxelBQOS1rT210TUE/view

Checked alternators are working.

I was thinking of doing a megavehicles mod. Do you want to PR that?

[quote=“Chezzo, post:11, topic:12965”]Awesome, IRC user Aabbcc was able to put it all into a mod, and in addition, he managed to fix the battery consumption as well. Thanks Aabbcc!

https://drive.google.com/file/d/0B0btuC1DG_yxelBQOS1rT210TUE/view[/quote]The values I used were mostly by eyeballing it, I will certainly be playing around to see if more or less is more fitting.

Does that not make electric engines 150x more efficient (thats 150’00% not 150%)?

Looks like the bug could be in blazemod. There is a candidate fix on GH awaiting further testing.

I’m not sure that’s the only source of the bug. Been idly testing with spawned vehicles for a while on a 100% vanilla map (#1930) and while car’s tanks seem to be doing okay (another found gasoline usage to have increased in vanilla by roughly 200%) electric vehicles still lose charge alarmingly quickly. For the sake of a repeatable test, I just emptied the ‘tank’ of a default electric scooter in 15 map tiles, or the equivalent of a medium-sized city. I’ll report back with some other electric vehicles, but as it stands that’s still much worse than it should be.

EDIT: Just repeated the test with the Electric SUV, and found a range of ~85 map tiles, or the difference between two or three towns, depending on your mapgen. This is a bit closer to reasonable, but still definitively shorter range than one would expect from an all-electric SUV. However, as one doesn’t currently exist in the real world, this was perhaps not the best vehicle to test first, after the scooter.

EDIT Jr.: Just tested with the Electric Car to reach a range of ~115 tiles. There’s obviously going to be some standard deviation here, as with the other tests, but it’s fair as a rough estimate. On this All-Default world I’ve been testing in, that took me from my starting city, across a river and through three towns before dying roughly halfway to the next. As with the previous tests, this was along main roads, avoiding off-roading as much as possible and driving at a more-or-less steady 60mph as most people likely would, IRL.

EDIT The Third: Perhaps time is a useful comparison here, instead of mere in-game distance. The electric scooter goes from full to dead in under ten minutes in-game (easily less than a minute, in real time), at 60 MPH along a straight road. The electric car dies in about three hours under similar conditions. In the real world, these would be completely and utterly realistic, but I can appreciate the need for some compression in a video game. However, in-game these numbers still seem low, especially the scooter which, with this sort of rate, serves no practical purpose in-game except a convenient find if you’re being chased. But an electric car (especially in this near-future) seems like a pretty ideal solution to early-game travel issues for some people, and having one that could easily die during a trip from HomeBaseA to LootableShoppingMallB seems like it’s still painfully unbalanced and needs fixing.

Problems with electric motors predate the recent vehicle PR which didn’t change battery efficiency. The blazemod issue is a literal 50x increase in gasoline efficiency so I’m fairly confident that’s the issue here

[quote=“mugling, post:14, topic:12965”]Does that not make electric engines 150x more efficient (thats 150’00% not 150%)?[/quote]I don’t know exactly how the background energy calc goes, but it should tell you just how borked it is that you need that high a value. I will reiterate, without it (and no blaze mod or anything either), a regular electric engine runs down the biggest storage battery in less than 20 minutes.

150 may be too high, I had tested with 300, 30 and 75 and the later two felt too low (with 75: 3~5 hours of fooling around = 10% battery, that may be fine for the big engine for large vehicles, not for the regular one for cars). I feel that the target number should be between 100 and 200, so I gave it the same as gas as a placeholder.

Can someone confirm that pre-5901, these range figures were still accurate? I personally don’t have the know-how to build from source on Windows, nor do I know where you find an executable older than what’s given on dev.narc.co

If that really is the case, I’m more than happy to drop the subject in favor of a opening a new Issue regarding electric vehicle range on Git. I don’t personally have the experience with them to confirm or deny any recent changes in range, as I haven’t started driving in-game until these complaints started pouring in.

EDIT’s Fourth Cousin: it’s worth noting I’m still expanding on the numbers in my original post at the top of this page, in case you don’t happen to have checked it again.

[quote=“Obsi, post:8, topic:12965”]running a generator , to recharge anything seems not viable anymore, they just run all my fuel dry before i can recharge even the smallest of batteries…
I had a V-twin engine in my mobile base that run car, moto and truck alternators, just for recharging… since the update i thought that it somehow took into account the vehicle weight even if i wasn’t accelerating it to anywhere, so i transfered the generator module to a new light frame with the new motorbike engine 0,4l and also tried to use a Wankel one with same results… fuel goes bye bye too fast!
what am i doing wrong? any suggestions?[/quote]

Last I checked, the kind of engine you use makes a difference. I was recommended to use a smaller engine, one of those one-cylinder ones, and that’s been able to run for weeks on a single full tank of gasoline. Power was kind of a struggle, but this was running a fridge, lights, and a recharger unit on and off. Fully sustainable.

Your tank might also leak. That’s worth looking at. It’s one of the biggest obstacles about siphoning cars that have been loaded for a while, actually.