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HOI4 Dev Diary - Fuel

Hi everyone! We have now been working on Man the Guns for a bit and it is time to kick off dev diaries again!

For those who missed it, Man the Guns is the expansion we are currently working on. The main theme is naval warfare and it will be accompanied by the 1.6 ‘Ironclad’ free update. There is no release date yet. We will let you know when we can commit to a date :)
So without further ado, rev up your engines! Today we are going to be talking about fuel...

Fuel is something we originally decided to abstract into the production of vehicles in HOI4. The reasons for this were twofold: It simplified things, making the game easier to get into and learn and it avoided issues with fuel stockpiling in HOI3 (I’ll get to that later). I still think these were worthwhile tradeoffs with the gameplay impacts it had, but some areas, particularly naval warfare, never felt right without an overall worry over a supply for fuel, which essentially drove Japanese war planning historically. This in combination with a feeling that our fans can for sure handle a little nudge towards complexity now kinda cemented the idea that we couldn’t really make a naval expansion without expanding on this area.

upload_2018-6-27_13-32-30.png

(no numbers are final etc ;))

Land
Fuel is used by trucks, tanks and other land equipment with engines in your divisions. They will use much more when fighting and moving than when stationary or during strategic redeployment (in fact right now those consume no fuel, but that might change with balance work). A division carries a bit of fuel with it ( much like how supply works), so there is a short grace period if cut off. If a division is in bad supply it will refill its fuel more slowly (meaning you won’t be able to attack or move rapidly as frequently), and you might even be unable to refill at all if totally cut off. Being without fuel will negatively affect the stats of the battalions that need it as well as severely impact speed depending on how low they are.
upload_2018-6-27_13-3-24.png


Air
Your active air wings will consume fuel. The amount will naturally depend on the type of plane (strat bombers love to guzzle down that fuel) but also what mission type. Planes on interception will be very fuel efficient as they only take off when there are enemies attacking ground targets or bombing etc. Transport planes on air supply missions will also be able to deliver fuel to pockets etc. When low on fuel air wings suffer big efficiency penalties.

Sea
Running a lot of active capital ships is something you will need to be careful with in Man the Guns. These behemoths will be going through your fuel stockpile like starved baby whales on the teat. To handle this and make fleets act more realistically and in a more controlled manner we have changed quite a bit here, so stay tuned for future diaries. The main point is that big fleets are costly to run and you will need to make decisions on how to best utilize them and how much to fit into the rest of your fuel use. Speaking of, you’ll be able to control who gets first dibs on fuel through prioritization just like with equipment (but we are also working on adding extra controls on top of this so you can more easily balance between the different branches of the armed forces). A fleet that is low on fuel will suffer penalties to its stats as well as operational range.


Production
Fuel is produced from unused oil, and equipment that used to use oil now no longer need that to be produced. I am currently looking into possibly adding copper or another resource in its place (and in some other places), but we will see if that ends up being a good idea or not ;) Will let you know. Anyways, if you are low on fuel there are several ways to go:
  • Acquire more oil rich states.
  • Increase infrastructure on your own oil rich states.
  • Trade for foreign oil.
  • Build synthetic refineries.
  • Lend leased fuel.
  • Capture enemy stockpiles.
  • Research improved oil to fuel conversion technologies.
  • Each unit of oil you have access to use your current techs to generate a certain amount of fuel. This fuel is then put into your stockpile for use by your forces.
Screenshot_2.jpg


Stockpiling
Fuel is possible to stockpile, in fact it is necessary if you can’t guarantee a steady stream of produced fuel during wartime. The size of your national stockpile will depend on the number of states and their infrastructure, your economic law and if you have built Fuel Silos. This is a new building that takes up shared slots and will probably provide the majority of your stockpile space. It is also a building that can be damaged from bombing etc. which in the worst case could lead to a loss of fuel. Capitulating enemy neighbors is also going to be a good way of acquiring more fuel as it will work just like seizing their equipment stockpile in that respect.

upload_2018-6-27_11-41-38.png


HOI3 also had stockpilable fuel, and there it was quite a problem. As a beginner you did not know how much (or even that you had to) stockpile and as an experienced player there was no issue in making a stockpile big enough that you wouldn't ever have to worry. In HoI4 we are aiming to force a tradeoff between building up your industry and increasing the stockpile (have to spend civilian factories to get more oil from trade instead of building more factories) as well as trying to keep the total amount you can stockpile within reasonable bounds. Our goal is fuel as something you’ll need to consider for all your operations and playing it really safe will mean less industrial output in the long run.

Since I bet this will be the first question, fuel is going to be in the free update, but there will of course be features in the paid expansion that tie into it (stay tuned for more diaries!).

We are still working on all things fuel so I’ll wrap up here. Hopefully it gave you an idea of what we have done and are planning to do. I’ve saved some interfaces talk for future diaries, and also, be aware that many things could end up changing based on gameplay feedback. Rest assured though, I’ll keep you updated on stuff like that in these diaries up to release. This is not really anything out of the ordinary, but I usually keep systems like this that need long term balance and iteration for later. Fuel however ties into a lot of future topics, so I wanna make sure you are all clued in :)

Now for something completely different...
I assume nobody has managed to avoid having their mailbox fill up with fun updated privacy policies and things related to the new European General Data Protection Regulations (GDPR). During all this a really smooth looking lawyer dog in the smartest little suit I have ever seen came over to visit us from Brussels. He told us there are a bunch of regulations we too need to follow in our games… so to make sure we remained Good Boys in the eyes of the law we have added a couple of things to Hearts of Iron IV. The most important is to include our Privacy Policy in the game and making it easy to find.
upload_2018-6-27_11-45-24.png


Legal texts are long and boring and nothing has really changed in how we do things. So I would rather spend my time answering questions here and writing the rest of the diary, so I will refer you to check it out ingame or here if you want to.

What I would rather talk about is how gathering data from players is useful to us. Because it is. Super useful! Without telemetry we would be resorting to guesses and risk only the most vocal minorities to be heard. For example, telemetry data is one of the major things we look at for deciding what nations to develop focus trees on. We get data on how popular difference choices are for focuses, letting us spot balance issues or unpopular paths that could use some love and care. We can spot if new out of sync errors are introduced in multiplayer in graphs and get crash reports automatically uploaded to help us fix problems easily. All this, combined with a scoopful of forum reading, is what helps us steer this ship, so thanks for helping :)

Oh I almost forgot, because we had to make the GDPR compliance hotfix we managed to sneak in a fix you guys have been asking for. We solved an issue for a case in China (similar things could also happen elsewhere) when a nation had both a takeover and inherited wars (like when seizing ownership in the Chinese power struggle) and was at the same time occupied. As a Japanese player this would lead to the less than happy situation of seeing your occupied areas flip back to the enemy and leaving troops cut off from supply. We also fixed a crash issue that was reported in some big mods. The patch should be releasing shortly.

Next week some of the team will be on summer vacation (including me!) but Bratyn is going to be here to talk about all the awesome stuff he has been doing with Britain, so don't forget to tune in!

  • Fuel for Thought
  • The Rise of Legal Pooch: GDPR always strike twice!
  • How we sell your personal data to Big Pharma for cocaine in 3 easy steps!
  • We have updated our fuel policy
  • Starved Baby Whales on the Teat is actually the name of the HoI 4 punk rock band playing at PDXCON 2019
  • Fuelling your conquests
  • Some of your data is belong to us, if you are okay with that
  • Help us help you help us
  • Our coders call it Nightmare Fuel actually
  • Adding fuel to the fire that engulfs the world
  • Anyone doing a dramatic reading of our privacy policy may request one Admiral to be added to the game
  • Proudly Introducing Gasoline Mana
 
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Tankettes?

Tankettes being separate upgrade from 1936 Light Tanks don't make that much of a sense IMO.

If anything, Armored Cars would make more sense - but there is possibility I'm talking utter nonsense :)
 
What I would rather talk about is how gathering data from players is useful to us. Because it is. Super useful! Without telemetry we would be resorting to guesses and risk only the most vocal minorities to be heard. For example, telemetry data is one of the major things we look at for deciding what nations to develop focus trees on.
Could you share the most popular nations in single player right now?

I remember that some time ago USSR was on the second place, right behind Germany. Could it be possible, based on that (in case if USSR is still popular, which I'm quite sure is still true), for you guys to revise USSR's focus tree (which badly needs to be redone) in Man the Guns despite USSR having little to do with the main theme of the expansion? Just like you did with Germany in Waking the Tiger?
 
Fuel is already represented in game - You need oil to produce certain types of equipment, equipment takes attrition/losses when used, so not enough oil in the long run means you will not be able to keep your air wings/divisions fully equipped if you are using them.

Don't know why you spend time to make the game more complicated.
 
Tankettes being separate upgrade from 1936 Light Tanks don't make that much of a sense IMO.

If anything, Armored Cars would make more sense - but there is possibility I'm talking utter nonsense :)
But as someone pointed out armored cars were introduced way before 1939
 
Could you share the most popular nations in single player right now?

I remember that some time ago USSR was on the second place, right behind Germany. Could it be possible, based on that (in case if USSR is still popular, which I'm quite sure is still true), for you guys to revise USSR's focus tree (which badly needs to be redone) in Man the Guns despite USSR having little to do with the main theme of the expansion? Just like you did with Germany in Waking the Tiger?


Around 8 minute mark or so if my memory serves well
 
What happens if enemy takes your province with fuel silos? And also do ships need to be in ports to refuel.
Thank you
The owner loses the storage space, but it is not captured until capitulation.

Question 1:
What happens if the enemy takes your province with full silos, which leads to a situation where you have less oil storage capacity than oil? Do you lose the exceeding oil units? And what if you reconquer the province? Will the oil disappear into thin air?

Question 2:
Does the strategically redeploy function consume fuel? I would assume so, cause units are transported by rail.
(Or were trains powered by coal?)

Question 3:
Do Tanks consume Fuel when strategically redeployed? If no, why shouldn't I redeploy them instead of moving them? If yes, wouldn't it be to expensive to redeploy them for example from france to russia? Did you find some kind of tradeoff for this problem?
 
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Could you share the most popular nations in single player right now?

I remember that some time ago USSR was on the second place, right behind Germany. Could it be possible, based on that (in case if USSR is still popular, which I'm quite sure is still true), for you guys to revise USSR's focus tree (which badly needs to be redone) in Man the Guns despite USSR having little to do with the main theme of the expansion? Just like you did with Germany in Waking the Tiger?

USA and UK are the only trees that will be reworked in the current expansion. The other trees will be for new nations.
 
While popularity is one of the major reasons for overhauls, it is not the only one. Other reasons include: Thematically appropriate for the DLC, current status of the tree (some trees are blatantly in worse shape than others), etc.
 
Well, that's too bad, but a question on fuel modding itself then: how moddable is it? And more specifically, can we introduce new things that take fuel besides the three branches?

It is a stat on equipment, much like soft attack. There are a bunch of modifiers that affect fuel usage. That's about it.

@podcat @Archangel85

Regarding Land units:
  1. So the fuel consumption is determined by what the unit is doing but what about terrain? Will we see larger consumption in town, mountain or jungle type regions for example? Or is that only determine by the region's infrastructure?
  2. Did you plane to add a fuel specialisation? Gasoline or Diesel? And if yes any plans about advantages & counterparts? (Diesel: better reliability slower units, Gazoline: faster but less reliable for example)

1. Well if a tank takes 2 days to move into a province because it is a forest and that reduces its speed, then it automatically requires more fuel.
2. Not in MtG probably.

Air:
  1. Any chances to see the implementations of new special missions? "Fuel Tank bombing mission"

It should be tied into the strategic air priority menu.
 
On the 22nd June 1941 Germany had just enough stockpile of fuel for 4 months of mobile warfare. Main goal of Barbarossa was reaching Caucasian oil fields, some think that that was main reason to attack USSR in the first place. Diverting army center towards Kiev during 1941 was due that goal. When that failed for reasons, some says that generals saw Moscow as priority, offensive into south will continue in 1942, but now on much limited scope than what was Barbarossa year before. After 1942 Germany lost its ability to wage any kind of offensive mobile warfare on a larger scale (they had tanks and airplanes but no fuel for them)

So glad fuel is getting in, no more arcade run your tanks all over the world and produce 20 000 fighters and have them up and running whole game. Lets make hoi strategy again!
 
@podcat @Archangel85

Regarding Land units:
  1. So the fuel consumption is determined by what the unit is doing but what about terrain? Will we see larger consumption in town, mountain or jungle type regions for example? Or is that only determine by the region's infrastructure?
  2. Did you plane to add a fuel specialisation? Gasoline or Diesel? And if yes any plans about advantages & counterparts? (Diesel: better reliability slower units, Gazoline: faster but less reliable for example)
Air:
  1. Any chances to see the implementations of new special missions? "Fuel depot bombing mission"
Naval:
  1. Regarding the convoy raiding, since it is pretty easy to distinguish a tanker from a normal convoy ship, any chance to see more focused mission? Covoy raiding and Tanker raiding? (you might think it is a stupid question but it makes sense to me haha)
Decision:
  1. New decision alowing the player to destroy is own fuel depots or setting fire to his own old fields to force the advancing enemy to repair before starting using, getting ressources? (Scorched earth)
Do you know thag you can select the priority buildings in strat bombing?
 
Oh I almost forgot, because we had to make the GDPR compliance hotfix we managed to sneak in a fix you guys have been asking for. We solved an issue for a case in China (similar things could also happen elsewhere) when a nation had both a takeover and inherited wars (like when seizing ownership in the Chinese power struggle) and was at the same time occupied. As a Japanese player this would lead to the less than happy situation of seeing your occupied areas flip back to the enemy and leaving troops cut off from supply. We also fixed a crash issue that was reported in some big mods. The patch should be releasing shortly.

[/SPOILER]

Oh god yes, thank you.
 
I think I would rightly assume that lack of fuel for tanks would negatively impact stats like soft attack, speed and breakthrough, as the tank can make less use of it because its moving around less. But what about its "inherent" stats like armor and piercing that would be constant, will they be affected?
 
I think I would rightly assume that lack of fuel for tanks would negatively impact stats like soft attack, speed and breakthrough, as the tank can make less use of it because its moving around less. But what about its "inherent" stats like armor and piercing that would be constant, will they be affected?
Well armour and piercing may not stay constant as if your low or out of fuel you can't manoeuvre to present you most armoured side or take the shot at the enemies weakest points.