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Dev Corner | Thermodynamics

If you missed the previous Dev Corner, check it out here!


Briefing: Thermodynamics
Author:
@Zwirbaum


Hello everyone!

It has been eight days since the last dev corner, which means it is time for another one. Last time, I was talking about some of the new naval concepts and changes coming to the Hearts of Iron IV. Today I will be talking about the introduction of Coal and Energy into the game. As a casual reminder keep in mind that everything discussed here is in a relatively early stage, and as such is subject to change.I also want to add that not every dev corner will be a long one, and some may end up on a rather short side. But without further ado, let’s keep this lump of coal rolling.

For the first time since the launch of the game we will be adding a new resource to the game, as every other resource, Steel, Rubber, Tungsten, Chromium, Aluminium and Oil were since day 1 in-game (with Oil getting Facelift in Man the Guns to be used for Fuel production instead of equipment production). This resource is Coal - to put it very briefly it will be serving as a ‘fuel’ in the form of Energy for your industry to keep it running efficiently.

Core Concept
What are some of the goals when it comes to adding Coal & Energy, and what do we want to achieve with it?
  • We want to introduce a potential soft-limit on the current almost limitless industrial expansion.
  • Increase importance on expanding and securing a resource base for your needs.
  • Provide a bit more interesting choices when it comes to economic laws, give some incentive for a player to consider ‘demobilize’ at some point during the gameplay, and that War Economy / Total Mobilization is not always the one and the only one right choice.
  • We are not aiming at creating a super complicated or overly complex system for energy/economy model

What is all the fuse about?

dc_thermodynamics_001.png

Sardinia starts with 2 units of Coal at the beginning of the game. As usual, numbers are subject to change, so please do not despair yet.

Base Concept
So the system works like this: Coal is excavated just like every other resource in-game. Each unit of Coal that you have for your own use (so not traded away) will produce a set amount of Energy, which then in turn is used to power up your industry - your civilian, military factories and naval dockyards, which for the ease I’ll be later calling them in this dev corner as ‘factory’. Each Factory, regardless of the type, has the same base Energy demand, so what you are seeing in the top bar as your industry size should also give you a very rough estimate of the demand.


dc_thermodynamics_002.png

This totally mysterious country, that is totally unrelated to Sardinia from the previous screenshot starts with 56 factories, and now has a mysterious bar under the factory count.

Economy of the Scale
However the base Energy demand is not everything, as each Factory you own will also introduce a little extra scaling cost to the demand per factory, so a small, undeveloped minor country will be able to sustain their few factories with a rather small amount of coal, while historically accurate Luxembourg spanning across Eurasia will require much more energy in order to effectively satisfy the ever hungry maw of their Industry.

Lower Mobilization Law is your friend?
Most, if not all, economic laws will also have factory energy consumption modifiers, which will essentially either increase or decrease how much each factory (including the ‘scaled’ portion from ‘size’ of the industry) will demand energy. Higher mobilization laws will have higher energy demand, to represent longer working hours, more shifts etc.

dc_thermodynamics_003.png

Economy Law picker will also now proudly display the energy consumption modifier at the first glance, so that you do not need to scour through the tooltip to find the modifier. Before you start going crazy with guessing what is the second number, it is just the expected amount of consumer goods - the icon is currently placeholderish, as we haven’t adjusted the previous icon yet.

How does it work though?
I will start with a quick reminder how the Civilian, Naval and Military Industry operate in-game currently. Essentially each of the ‘factories’ have a specific base amount of output valued in points that they contribute daily to. (5, 2.5 and 4.5 respectively). And that was further modified by all the technologies, laws, ideas, ministers, national spirits with various ‘Construction Speed’ or ‘Dockyard/Factory outputs’ modifiers. I am not mentioning Production Efficiency, as that was unique to the Military Factories.

So how will that operate in the brave new world? We will now have a base output for each of the industry types - which means that regardless of the energy, you will always have at least this much output from your factories. And there will be ‘fully powered’ output values for the industry. Depending on the energy ratio you are providing, you will end up somewhere on that scale, e.g. If you have 50% energy - you will be getting output that is ‘50%’ way from the base output to the fully powered up. All the previously mentioned Construction Speed, Dockyard/Factory Output modifiers will also be scaled accordingly to the % of the energy you have.

dc_thermodynamics_004.png

This is the current debug display that allows us to see energy demand & consumption, and how much it impacts the industry. In this case we have 26.7% energy needs satisfied, and it means that each of our CICs provide 4.2 IC daily, MIC provides 3.7 IC daily and NIC provides 2.1 IC daily. Of course as usual, reminder that all values are subject to change.

Wrapping Up
And that is all from this dev corner. While this post is one the shorter side, impact from adding this ‘system’ could of course be quite big - however thanks to covering only this one matter, feedback, opinions, suggestions from you dear readers, should be laser-focused and allow us to get a much clearer picture of what you are thinking. Anyways, that is all from me for this week, and next week Thomas will be back with more things to say about the Factions.

Thanks for reading, and until next time, farewell!

/Zwirbaum
 
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That sounds very solid. However, the problem which is once again blatantly ignored (at least for now, as there has been no mention of it) is logistics. Germany occupying most of Europe theoretically had just enough coal production on controlled territories to keep them all coal supplied; but re-distributing this coal over the areas where it was in short supply was a huge strain for the transport system (source: Wages of Destruction). In HoI4, we have resources "conveniently" teleport over thousands of kilometers for free, and having to move them by water is somehow a negative ingame despite absolutely being a positive IRL. Middle Eastern Oil and Singaporean Rubber are delivered to Berlin via obscure underground pipes no one gets to target or even maintain.

If the real life challenges of coal supply follow this vein and are perverted into making coal artificially rare right across its deposits, that would be a poor game design indeed.


Maybe resources should be shipped the same way weapons are shipped when sold? Having enough resources would take into account your previous month’s surplus. This would make raiding more common for players. For large empires, resources that aren’t connected via land routes should use convoys for internal shipping to the capital.
 
I love that change and the introduction of energy and coal. Is it possible to get a like+10% buildspeed for civ in the civilian Industry Economy law? that would make it more apealing
 
The way i see it, this is a solution in search of a problem. To make it work, you need to:
- rework the focus trees
- mix and match a bunch of mechanisms (such as refineries)
- figure out how to make dams work in historical way
- figure out how to not screw up small
Countries
Etc etc etc

And for what? Lets remind ourselves of basic issues that havent been resolved in 10 years:
- AI cant use paratroopers
- AI doesnt know how to use frontlines
- AI still ships tons of divisions all around the world for no apparent reason
- AI still cant defend convoys
- AI still doesnt know how to make a good tank or plane or ship
- AI still often produces old equipment after researching new stuff
- navy is still broken

This is a war game. Fix the war before you start messing with the economic system (which s barely functioning as is).
 
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Reserved for Developer replies~

Zwirbaum replies;


Yes, Coal does operate just like other resources - and is a tradable one. As Coal is 'regular resource' it is subject to Excavation technologies, so you can get more Coal out of Coal.

EDIT FOR THE EDIT GOD:

Civilian Nuclear Reactor and Dams do interact with the system.


Those are not shaking hands you were looking for


It is a bit too early to talk about modding, but IIRC you can set in the define which resource is responsible for energy purposes.

This is waaaaaay to eaaarly to talk about modding, but I think technically speaking it is possible, though not sure if it wouldn't run into some potential side effects.


No plans for it at the moment.

Uranium would be a resource that probably does not matter at all until ~1942/1943, and it's importance only increase (or even skyrocket) after that date, making it a resource that is completely ignored for the first half of the game. I'm not a fan of adding a resource that could matter only in some runs.


Right now Dams and Civilian Nuclear Reactors provide a reduction in the energy factories from this state are using. (Local Energy Consumption Modifier), so let's say if the modifier would be -25%, then factories located in such state instead of consuming 100 energy would now consume 75 energy. (Random numbers are random)


Coal is a normally tradable resource.

ATM equal distribution


And here I was sitting and thinking that I run out of ideas of how to name future dev corners. Truly from the depths of my heart, thank you! :)


1750972060305.png




Wrongwraith replies;

Currently we are letting Industry in states with Dams or Reactors require less coal.

We will evaluate how it works. There are, as you say, other ways of doing it.
I agree. Why not just have other types of power plants create Energy? Yes, there are things like making steel that, with contemporary technology, could only be done by burning coal. But that's never close to a majority.
 
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How will the new coal resource interact with the synthetic petroleum and synthetic rubber tech trees/buildings? Will we now need to have coal in order to run the synthetic fuel or synthetic rubber, since synthetic fuel was derived from liquified coal, and the synthetic rubber from the polymerization of cracked petroleum, and/or were based on acetylene that was ultimately derived from coal? Or are they still manufacturing synthetics basically from thin air since you explicitly noted "energy" as largely being a stand-in for industrial coal?

And while we're on the subject of fuels...any thoughts on breaking fuel down into petrol, avgas, and heavy fuel oil (marine oil) as distinct resources?
 
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The way i see it, this is a solution in search of a problem. To make it work, you need to:
- rework the focus trees
- mix and match a bunch of mechanisms (such as refineries)
- figure out how to make dams work in historical way
- figure out how to not screw up small
Countries
Etc etc etc

And for what? Lets remind ourselves of basic issues that havent been resolved in 10 years:
- AI cant use paratroopers
- AI doesnt know how to use frontlines
- AI still ships tons of divisions all around the world for no apparent reason
- AI still cant defend convoys
- AI still doesnt know how to make a good tank or plane or ship
- AI still often produces old equipment after researching new stuff
- navy is still broken

This is a war game. Fix the war before you start messing with the economic system (which s barely functioning as is).
I actually agree. I think coal although interesting and adding some strategic choices it is not a big enough step up to justify the hassle to adjust everything.
 
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Since dams seem much more important this update, can we expect more dams added both at the start and buildable? Italy for example was the target of one of the first (even if failed) dam raids, and it has a focus based exactly on building dams (investments in Edison)
 
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As a player since 2016 the game is starting to feel bloated and overwhelming and I do not think it will be as enjoyable to try to manage all of the new resources. Will there be an updated tutorial or something to help out new players or someone like me who is getting turned off by the additional things to manage?
You have a point that some of this stuff is not fun or interesting. We need automatic balancing options for strategic resources for QoL.
 
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Would this be the time to separate clearly aluminium plants from bauxite deposits ? (Canada for instance is clearly meant to have aluminium from (it should be noted, massive) hydroplants, while Greece and Netherlands colonies from bauxite.
 
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You have a point that some of this stuff is not fun or interesting. We need automatic balancing options for strategic resources for QoL.
I would love expanded game options to allow you to toggle dlc features on and off without having to disable the dlc. Spies, international market, licensing, designers, etc.
 
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A. Coal map of Turkey in 1940:
View attachment 1326820

The Ereğli–Zonguldak–Amasra–Cide region holds the largest coal reserves in Türkiye and is one of the richest in the country. Thanks to this area, Türkiye ranks among the top 12 countries globally in terms of coal reserves. Coal extraction by Turks in this region dates back to the 1850s. (You can also look to the small maps below the main one.)

Lignite reserves are also found throughout Anatolia, spread across various regions.
View attachment 1326827
"The most significant lignite reserves were developed around 1939 in Tunçbilek/Tavşanlı (Kütahya) and Soma (Manisa).
There were also lignite reserves in Çeltek, Amasya, but these were not exploited until around 1955, which falls outside the timeline.

In 1948, Türkiye's second coal-fired power plant was built in Çatalağzı, Zonguldak:
Çatalağzı power station – Wikipedia
(It's no surprise the state chose to build one of its largest power stations close to the hard coal reserves—and also kickstarted its steel industry in Ereğli, within the same region.)

B.
During the early Republican era, all mining and electricity operations — including coal — were directly managed by the state-owned bank Etibank.
Because of this, I believe the developers should add Etibank as a new Industrial Concern for Turkey.
Etibank – Wikipedia
Etibank in my mod:
View attachment 1326828


C. Another important milestone was the construction of Türkiye’s first coal-powered power station in 1914 at Silahtarağa, Istanbul:
Silahtarağa Power Station – Wikipedia
It remained the main electricity supplier for the entire city until the early 1950s, when Istanbul was finally connected to the Çatalağzı power station in Zonguldak.
Given this historical role, I believe Istanbul should have a modifier or some kind of special bonus to energy production, making it a more strategically valuable state.
I’ve shared information about Turkish coal and electricity developments across Anatolia—hope it helps.
@Zwirbaum
@Wrongwraith
 
Inb4 steel quality is introduced. We can funnel other resources like coal towards steel production to get higher quality steal -> better armor.
We have your number Vicky3. Death by a thousand cuts it is.
 
I’m worried about the same things just based on the history implications. The devs seem to have designed a system which somehow makes coal the most important resource on the map, and then plan to put in in very limited quantities all over the map. They are aware this is a game about WW2 right? Coal is probably the most abundant resource in the world at this point in history (at least in comparison to the other resources they include in game like Tungsten or Chromium). And WW2 was literally the period that coal power began to decline and be replaced by Natural Gas and Oil (not to mention up and coming technologies like Nuclear). I’m not saying I’m opposed to coal and power being represented in the game; but representing it in a way where most nations won’t be able to sustain their own power consumption even in peacetime, making military factories functionally more efficient on civilian economy, and making dams (which for some nations, including major powers like Italy, were the primary source of power) provide a slight consumption reduction, makes me question the overall benefit that this system has.

Don’t get me wrong, I want power in the game. I just don’t want power to instantly become the worst mechanic in the game. This feels very unbalanced to say the least, and it feels like they’re addressing the disarmament problem of endgame from the exact opposite direction that they should be. I have to admit, I was initially excited when I first read this Dev diary as I was excited for this new system, but after rereading the dev diary a few times and seeing some of the dev responses explaining how it actually works, I am becoming pessimistic about this system very quickly. Great concept, poor execution.

To me, the fact that power will only be produced by coal and that coal will have no use as fuel for ships or trains, indicate that this is going to be another one of those new mechanics that is added on top of the rest of the game rather than comprehensibly worked into and made a organic part of the game. I think this is a big, and increasing, problem of HOI4, that they keep adding "new stuff" that while keeping the game "fresh" often havent received the resourcing needed to do it properly and is left as another adon-system rather than a comprehensive improvement to how the game funcions.

I think the dams are kind of an interesting illustration, in that they were only added to a few nations, have a limited effect on the game and when the next DLC comes around that could make dams more relevant, that opportunity is not taken.
 
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To me, the fact that power will only be produced by coal and that coal will have no use as fuel for ships or trains, indicate that this is going to be another one of those new mechanics that is added on top of the rest of the game rather than comprehensibly worked into and made a organic part of the game. I think this is a big, and increasing, problem of HOI4, that they keep adding "new stuff" that while keeping the game "fresh" often havent received the resourcing needed to do it properly and is left as another adon-system rather than a comprehensive improvement to how the game funcions.

I think the dams are kind of an interesting illustration, in that they were only added to a few nations, have a limited effect on the game and when the next DLC comes around that could make dams more relevant, that opportunity is not taken.

At least for Canada, this is what I was trying to state, hydrodams were quite tied to generating powers for aluminium plants (this is a pet issue for me since release : the game clearly does not make the difference between countries that produced alumimiun itself (that is, they have very hungry for electricity plants to do so) and countries that produce bauxite, the raw material)
 
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Any chance in the current engine to get multi monitor support? Especially if you are fighting in multiple theaters having one screen being focused on an european front and another one in the pacifc to easily see what is going on everywhere would be really great.
 
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If I could directly post image here I would post wojak coal meme both as a response to the new resource and the mechanics being ass because it would add more unnecessary complexity
 
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Core Concept
What are some of the goals when it comes to adding Coal & Energy, and what do we want to achieve with it?
  • We want to introduce a potential soft-limit on the current almost limitless industrial expansion.
  • Increase importance on expanding and securing a resource base for your needs.
  • Provide a bit more interesting choices when it comes to economic laws, give some incentive for a player to consider ‘demobilize’ at some point during the gameplay, and that War Economy / Total Mobilization is not always the one and the only one right choice.
The way a game typically plays out, how many people actually play any meaningful amount beyond whatever "great war" their campaign crescendos at? Post war content is lacking, and the big war is such a slog that after you look at your newly painted map its typically game over. Shouldn't the aim be making it so players have a harder time mobilizing outside of or *before* the war? (except historical Germany obviously as thats kind of their thing) Given the prevalence of "one and done" mechanics that have been introduced, I don't see the proper time being taken to do a balance pass across every "unique" country, IE has a focus tree, let alone all possibilities with releasables. Needing to balance civilian and military needs before and during a war makes sense as people can only be convinced to take so much punishment before support for any war will slowly start to collapse, I just don't see this as doing that.