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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.

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(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.
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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.
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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.

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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.
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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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Local shortages due to bad logistics, a broken down train network or bad management is not what I was after here. I meant strategic shortages.

Was Germany really not able to produce ammunition at a rate fast enough on the strategic level to such a degree that it impacted their entire plan of war? ( Like the fuel shortage did ).

I'm not for a second suggesting that fuel shouldn't go in before ammo (in no small part because ammo is kind of already in, in terms of the use of equipment during battle, although like fuel that doesn't hold true for ships and isn't perfect fof aircraft either) but (and going from memory) the Japanese, for example, had to limit their use of AA ammunition at a strategic level to the point that it had a material impact on the AA capability. Breaking it down to specific ammo types (like torpedoes, mines, etc.,) and this goes even moreso - all the majors took a while to ramp up their torpedo production, for example, which meant they had to be a bit more careful with the fish they had.

Such things were of strategic importance with artillery shells during the Great War but not so much in WWII. In fact, I see no compromise at all with rolling all aspects of ammunition supply into general supply in WWII.

In terms of ammo more broadly, I'm not sure this holds. It's not something that gets a lot of mentioning (logistics, and particularly industrial logistics, tends to get short shrift) but it's telling that when the Royal Navy started to rearm in 1935/36, when they were told it was time to be ready for a war in the next few years, the thing they focussed on first was building up ammunition stocks (and the industrial capacity to maintain them). Having a good ammunition plan could be the difference between being successful in a long war of attrition, for example, and in actual combat units could go through it pretty quickly.

A very rough back-of-the-envelope calculation puts ammunition expenditure by Ajax and Achilles at the Battle of the River Plate, for example, at 164 tons (80 per cent of their main gun ammunition) - which is the weight in metal and explosives of 23 Panzer IIIs (just the weight from the wiki page - we're still rocking it quick-and dirty) in less than an hour and a half of naval combat. Now, just going on weight, with a 50% discount factor (ammo was less complicated, but again, this is very rough), 11.5 Panzer IIIs is 138 MIC, plus the resources required while they're being built. At the moment, there's no differentiation between a nation that's built two CLs, but lacks the industrial base to supply them over time in combat, and a nation that's built two CLs and made sure they'll be able to keep fighting for as long as it takes.

You know what I really thought was missing from this game? Another resource to manage instead of fleshing out more countries' national focus trees was not the answer I would've given.

The devs have already said we're going to get more focus trees as well - it's not like the only thing included in MtG and the accompanying free update is in this DD :).
 
You know what I really thought was missing from this game? Another resource to manage instead of fleshing out more countries' national focus trees was not the answer I would've given.

If I'm going to pay for a new feature, I'd much rather it be something like fuel instead of focus trees, which modders can and do easily add to the game.

Plus, I mostly play Kaiserreich, anyway.
 
So yeah fuel is cool and all, but how about some updates on carrier air squadrons getting wiped out? Am I seriously going to have to wait until 2019 to have a fix for this? Several countries are currently unplayable and you might as well avoid the entire pacific theatre. I haven't heard a peep from the devs about it either.
 
Local shortages due to bad logistics, a broken down train network or bad management is not what I was after here. I meant strategic shortages.

Was Germany really not able to produce ammunition at a rate fast enough on the strategic level to such a degree that it impacted their entire plan of war? ( Like the fuel shortage did ).
Well I see, yes the lower level that we read, like operational and tactical then Ammo shortage rears its head much more than Strategic level reading. So I see what you're saying.

Germany did switch production from Arty shells, and didn't produce enough generally and especially after early Barbarossa when they thought the war won. Eg Manstein's operation in Sevastopol really felt it and some analyse point to the shortage being pivotal to the failure of the first attack.

Ammo production was a key strategic production priority. It took away from the ability to build more other stuff. I am very happy fuel is coming; but also stand by my stance that ammo was the critical production and supply issue. And would be good to have in the game.
 
So yeah fuel is cool and all, but how about some updates on carrier air squadrons getting wiped out? Am I seriously going to have to wait until 2019 to have a fix for this? Several countries are currently unplayable and you might as well avoid the entire pacific theatre. I haven't heard a peep from the devs about it either.

Well it took them forever to release a fix for the China issue, and the reason they probably released that now instead of in 1.6 is because they had to change terms and condition crap.

Dunno what's up with their plan but I've never seen a PDX team ignore such glaring bugs for so long. Are there mods that fix the carrier issue?
 
I am a bit concerned that would Axis AI be able to cope with the usage of fuel? Would Japan easily consume all of the fuel by sending their navy wondering around the world?
 
The owner loses the storage space, but it is not captured until capitulation

Bit silly if you take the province with the fuel silo's intact, surely you should have access to that fuel. Don't see why you have to wait till capitulation, to have access to probably a % of the fuel you captured.
 
How do synthethic refineries currently work? Do they still produce oil, or fuel directly
they produce oil. which is then coverted using conversion techs to fuel. so its a more expensive less efficient way compared to holding wells and trading

No way to destroy it, at least partially ?

you can destroy buildings as normal. just not more than one per state every month

I apologize if this has been answered already, but will fuel go bad while in storage? It's my understanding that processed fuels can only last about 6 months before needing stabilizing chemicals or other treatments.

no, the time scope isnt really long enough in hoi to make this have a real impact

Excess/unused oil after what?

Modders are still free to use the oil resource in production, and there could be other things tying it up.

Fuel Depot will work from my perspective as well. Although depot has more of a military connotation, I think it's still a more appropriate word than silo. However, the game is not my workproduct, so we'll see what the devs think about this. It's also a minor issue and it's already in the game, so they may view any time spent changing it as wasted.

Fuel Depot would work I think. its fine if its a military word as its used for the military

Great dev diary but now we need much more. Will ships also in combat burn more fuel?

Yea. historical numbers are something like 15x more tho in some cases. the issue is that our combats last a lot longer than "real" engagements so we cant have the same increase. been playing with 5x recently, but its all in flux. we shall see where it lands.

You know what I really thought was missing from this game? Another resource to manage instead of fleshing out more countries' national focus trees was not the answer I would've given.

6rZ8g8R.jpg


Bit silly if you take the province with the fuel silo's intact, surely you should have access to that fuel. Don't see why you have to wait till capitulation, to have access to probably a % of the fuel you captured.
The argument is that the owner would have just destroyed or moved it if it got too close to the front, so it makes more sense to me to have the capture on capitulate like other stuff
 
The argument is that the owner would have just destroyed or moved it if it got too close to the front, so it makes more sense to me to have the capture on capitulate like other stuff

Being able to capture some of the fuel when taking over a storage building could lead to some cool historical stuff like battle of the bulge where your Panzers don't got enough fuel to reach the objectives but there are fuel you can capture on the way.

I think both approaches could have some merits worth considering.

If all buildings were gradually damaged by combat instead of just infrastructure it would also work to have you capture a portion based on it's damage so drawn out battles see most of the fuel destroyed before capture.
 
Being able to capture some of the fuel when taking over a storage building could lead to some cool historical stuff like battle of the buldge where your Panzers don't got enough fuel to reach the objectives but there are fuel you can capture on the way.

I think both approaches could have some merits worth considering.

I know it is a typo but Battle of the Buldge... :D
 
A large item like a fuel depot would be hard to capture intact, but if you capture half a battalion of tanks they would certainly have their fuel intact. There are also smaller stockpiles at the unit level which could often be captured.
 
So yeah fuel is cool and all, but how about some updates on carrier air squadrons getting wiped out? Am I seriously going to have to wait until 2019 to have a fix for this? Several countries are currently unplayable and you might as well avoid the entire pacific theatre. I haven't heard a peep from the devs about it either.

This is literally their first Diary in any detail about stuff coming in new expansion and patch. These issues could be changed/fixed/etc in said patch, so have a little patience.
 
The argument is that the owner would have just destroyed or moved it if it got too close to the front, so it makes more sense to me to have the capture on capitulate like other stuff

Germany captured Fuel from Supply Depots- if the argument is that the Allies would've moved it- well then why didn't they in history?

Please let us capture Fuel. It kept the German War Machine going in part on the Western Front.
 
Couple of concerns:
1. Vietnam War: The US bombed the crap out of North Vietnam early in the war, particularly targetting oil depots. They dropped more bombs on little Vietnam than on Germany and Japan combined during WW2! Yet, the US didn't achieve anything cause the Vietnamese simply stored the oil underground and that was that.
--> Destroying oil/fuel depots via strategic bombing in HoI4 wouldn't be realistic.

2. Germany can easily built enough synth factories to be self-sufficient in oil and rubber. I'm sure that there'll be enough CIC left to build enough fuel storage as well. In the end will fuel even be a crucial resource for an IC powerhouse like Germany? Of course it's a matter of opportunity costs and you'll have to sacrifice other investments to a degree. But I think that fuel depots and synth factories should be much more expensive and you shouldn't be able to create an autark German economy. It's neither realistic nor does it make sense gameplay-wise.
 
My biggest concern is about the AI.
I dont think the AI will handle fuel well... As I said in the thread in which the expansion has been introduced, the AI cant handle airwings, production and recruitmenttab, naval distribution and army distribution well at all...

Im very pessimistic by now and this concern isnt in any form near to be negated.


Also, for balancereasons, limit the amount of synthetic refineries a country can have. I bet this will eas up fuel balancing.
As Axis it is so easy to out IC Britain and France. Especially with Germany which can handle that at its own.
It is no no problem at all to have many syth refineries by 39/40 and buy a shit ton of oil from Romania while they are upgrading their infrastructure to generate more.

Combine that with my concerns about the AI and my super pessimistoc state has unfortunatly evolved and now Im even more concerned about everything...


Different topic:
Also whats up with the SA nerf last patch?
Do you have statistics how this has has influenced the game? If you have these can you publish them please?