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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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"Study", huh? then what's next? Copper is important in war, so let's add copper. Gold was important in war so let's add gold feature. Gunpowder was important so add powder resorce. and ta-da! the vanila game turns into the Black-Ice mod!

I think HoI4's reason of success is simpler and easy-to-play compared to previous series. So players can fully focus on battle and war only. More casual, more players and newbies. But adding these features just makes game more complex and hard to adapt for new players.

Plus, this feature barely gives an advantage for countries. It gives more disadvantages, which only makes gameplay more annoying. Especially for minor nations.

"Realistic" is not always an answer.
We are talking about ENERGY! Not wool for coats, energy. Ultra basic need.

PS: Stalin studies the price of wool in Germany to see if Hitler would attack. Imagine the level it could reach. But of course, if having electricity seems crazy to you...
 
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The system seems to be very simple. No more complex that having rubber, steel or any other resource.
Like lack of steel reduce mil production. Lack of coal also reduce production. The more you have mills the more you need resources. All in all. This is not a big change!
 
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I agree with the stated goals of constraining exponential industrial growth, creating room for demobilization, and reflecting the strategic value of coal-rich areas. I just don't know if the concept presented here is the best way to do it.

Might be interesting to compare the ideas to the existing Better Mechanics: Production mod, which: adds passive attrition to standing armies; makes each factory more expensive than the last one; makes civilian factories consume steel, chromium and oil; and reduces fuel output per oil.
 
Interesting stuff, this will shake up the gameplay for sure!

i know those were just placeholder values for the economic laws, but War economy and total mobilization really shouldn't be consuming that much more power than civilian economy or early mobilization, because it's not just factories that are working longer hours, the resource management like coal mining is also working longer hours.

After all, when your mobilizing the economy for war, you're not just increasing Factory output, but the amount of resources you're producing as well.

Total mob costing 2x as much as war eco seems like it would kill that law except for in countries that have an abundance of energy resources.
 
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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.

Sound good. But is there also a change use this also as fuel for old ships? For example the german pocket ships and the Graf Admiral Spee has use coal. Let them need more coal/ energy and give this ships more visibility and fewer speed.


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.

All the previously mentioned Construction Speed, Dockyard/Factory Output modifiers will also be scaled accordingly to the % of the energy you have.

I am not shure but i believe that bring problems. Not for all - Majors can this better compensate as smaller. And don't forget stability work in the same way how the eneregy. When i have 0 stability (Manchukuo say Hello to Paradox!) what is my produce output with 0 or 50% energy? for me it looks then how a double malus. Same with building factorys. How work this with factorys they will claim from the overlord or they are out of map?


56 Factories with plenty dockyards, military factories, and rich convoys and manpower but in short of coal...... Japan seems to be the only possibility. But 42% stability and 55% war support...?

Must not Manchukuo have a lot of coal. Mengkuo to? Offer coal for autonomy? ;)


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)

It's helpfull but there are also (not all) startgame dams in regions where you have only place for 2-4 factorys. A Test for 0-1 will come when i mod my next dam for turkey between Ankara and Katsamonu.

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I agree with the stated goals of constraining exponential industrial growth, creating room for demobilization, and reflecting the strategic value of coal-rich areas. I just don't know if the concept presented here is the best way to do it.

Might be interesting to compare the ideas to the existing Better Mechanics: Production mod, which: adds passive attrition to standing armies; makes each factory more expensive than the last one; makes civilian factories consume steel, chromium and oil; and reduces fuel output per oil.
I hated that concept in Iron Curtain. Having an army of trucks takes up 90% of truck production just by standing around.
 
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I like the idea of adding more stuff that interacts with existing systems. This is a far, far, far better approach than how some other updates are handled.
But I would like to question if this push to take the world war out of a World War II game is the right direction?
Like demobilization in a war? Okay, but why? Every country was fully into a war economy, and none thought in the middle, "maybe we should step down because coal is expensive."


From a gameplay and design perspective, I’m all for the idea of introducing coal as an industry cap. It sounds interesting and could make late-game decisions matter more, with the compounding effect of having fewer troops in the field.
I think maybe we are not going far enough with this effect. You see, the resources are just there in the ground and instantly accessible. And I think that might be a point where we could additionally add a small gameplay interaction and contribute to the slowdown of industrial escalation.
We should think and plan around our extraction industries. So having regions with resources is not enough — you must build extraction industries to access them. This would limit the snowball effect of capturing a coal province, as you’d have to hope your enemy did the construction work. If not, you're slowed down because you need to build the extraction industries first before reaping the benefits. Additionally, with resistance there, you’re not as fast in integrating the newly conquered resources as before — not through a simple boring malus, but with a sensible and authentic decision around it.
 
An option to set the priority of coal/energy going to civilian factories, military factories and dockyards would be very nice, like the system in the logistics tab where we select priority of equipment going to armies, garrisons, upgrades etc. After 1941-42 I don't need my civilian factories at full power and similarly after getting the navy I need I can lower the energy priority of my dockyards.

Shouldn't oil also be used as a fuel for industries for oil rich countries?
 
I’m really excited and a little unsure when it comes to how the economic and industrial scaling changes would work. I would be curious to see how this update might effect every country. I was thinking that, if energy consumption is going to act like a resource, could countries that don't have many resources use captured industry, land, or current in game resources as a way to alleviate the energy strain? For example Germany and Japan are the two nations that need to quickly expand their industrial might to fight the allies, and rushing war economy or total mob, is currently the best way to do that. I’d love to see something like MEFO bills or a system where conquest could help keep the economy afloat and the energy usage lower than what the Allies would have. This also would help encourage the need to go down the right side of the industry tree more often for early and mid game.

Japan, on the other hand, feels like it’s missing that kind of idea or system. Right now, rushing Total Mobilization helps a bit build up your nation so that you can take on the USA, but it still feels like there’s no clear way to keep Japan on a solid industrial footing from 1937 through 1945. Are there any plans to introduce a system where capturing resources, like in the Dutch East Indies, Malaya, or Indochina, would help reduces the energy strain on the economy? I think that could really give players a reason to follow Japan’s historical expansion and make victory in China a must, otherwise your forced to either demobilize or historically attack the allies while bogged down in China.
 
I'm curious if with this introduction of coal, that we get more places for dams. Electrical Generation came primarily from coal at the time, but there was a huge amount of hydro power as well.

I would also be interested to see if we can get natural gas power plants, as those would be a very viable option for countries as the time. Also note that nuclear power doesn't really kick off until the 60s so if we can build those, I don't see why we can't build natural gas plants.
 
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