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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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Reading this, I have three initial concerns/thoughts that I am curious if they have been considered, and if there's any potential ideas to remedy them if not:

1. Even with the previously announced naval changes, navies are always going to be a lower priority for most people as you need a military and civilian industry to win a war no matter what. Logically therefore, isn't having every factory contribute to the same resource cost not just going to incentivise deleting every dockyard that isn't absolutely vital for stuff like convoys? If we just for example assumed 8 coal could power 4 dockyards, deleting 4 dockyards effectively translates to 1 more civilian factory you don't need to trade for resources, which I think most players would see as a good deal.

2. Currently in the game, and seemingly even with these anti-snowballing changes here, by the time you get to late game you'll likely have more factories than you actually need. Quite often come 1942 in a vanilla game I'm sat there with a large number of military factories I do not need because I already have enough equipment and enough factories to maintain stockpiles without all these extra ones. Is there going to be a way to "mothball" factories so that they don't get used and don't contribute to power consumption? With military factories and dockyards I assume you could just simply not assign them any lines to avoid them contributing to the cost, but things like repairs with civilian factories would constantly mean they turn on and off again no matter what, affecting your total costs.

3. How will factories gained from other countries(i.e taking reparations in peace deals or from puppets) factor into energy consumption? Will they just be treated the same as any other factory for the overlord that controls them, and factor into the same energy pool, or will they use the energy of the nation they are taken from?
 
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Great news. That means rares are next!

Will coal power synthetic plants also?
Any thoughts on having civilian economy better at producing civs, to add further incentive on when to mobilize the economy?
 
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Will nuclear reactors therefore be an end-game energy replacement for coal? What about oil, can it be refined to gas?
The "synthetic oil and rubber" plants should definitely consume notable amounts of coal. (At the very least like any other factory.)
 
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View attachment 1324166
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.​
Wait... What are those shaking hands?
 
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With the addition of coal to the game, could we also get an option to run our navy on that instead of oil? Probably best to represent this through new engine modules. Ie, if the ship has a coal boiler, it runs on coal, and with the traditional engine it will run on fuel.

We will probably need stockpiling mechanics for coal as well then, but I think that should be both doable and necessary. That way you also have some flexibility with regards to keeping your industry running when a few convoys get sunk.
 
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As a Sardinian, I was pretty excited to see my beloved Sardinia featured in your Dev Diary!!

Besides expressing my delight, I have a question: will the current focus trees be adjusted for coal and energy? Historically speaking, Sardinia was a producer of coal, and in 1937 Mussolini founded a mining city called Carbonia (carbone is the italian for coal) in south Sardinia to extract coal. I'm sure stuff like this happened in many places in the years before the war, will this be included?
 
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View attachment 1324164
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.
View attachment 1324166
56 Factories with plenty dockyards, military factories, and rich convoys and manpower but in short of coal...... Japan seems to be the only possibility. :oops: But 42% stability and 55% war support...?
 
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Can you make it so changes to your consumer goods will show how many factories you will gain or lose will be in the tooltip? Similarly if your energy demand changes can you make it show if you will be in a deficit?
 
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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?
 
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Currently we are letting Industry in states with Dams or Reactors require less coal.
I hope the reduction is substantial since dams are scarce and civilian npps are very late-game as well as expensive to build. Not to mention the fact that research reactors which you'll need to generate breakthroughs for nuclear in the first place are mutually exclusive.
 
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Currently we are letting Industry in states with Dams or Reactors require less coal.

Not sure this is the best approach honestly. Could you get the player to build coal refineries on a tile with coal/just have the amount of coal be automatically produced, and then have a total energy production from Dams+Reactors+Coal/Coal Plants and then sum up the energy cost and compare them. Also allow the player to prioritise if they should go to civilian/military/naval factories if they dont have enough.

And then optionally have companies that you can assign a state to, to boost a certain resources, like assigning it to Krupp (like in EU4 you can assign a state a holy order) you get a boost to steel production from krupp or oil from siemens or etc.
 
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Could I mod it so that the same resource produces both fuel & energy? In my Lord of the Rings mod, it would make sense for Food to be used for both military rations & civilian... food.
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.
 
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Not sure this is the best approach honestly. Could you get the player to build coal refineries on a tile with coal/just have the amount of coal be automatically produced, and then have a total energy production from Dams+Reactors+Coal/Coal Plants and then sum up the energy cost and compare them. Also allow the player to prioritise if they should go to civilian/military/naval factories if they dont have enough.

And then optionally have companies that you can assign a state to, to boost a certain resources, like assigning it to Krupp (like in EU4 you can assign a state a holy order) you get a boost to steel production from krupp or oil from siemens or etc.
We will evaluate how it works. There are, as you say, other ways of doing it.
 
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I assume this will be A large boost to most European powers (knowing they’d probably start with lots of coal) I have to wonder however how this will impact countries that naturally have less coal.

For this I’d like to give the Netherlands (shocker) as an example! The Netherlands historically has had less industry than Belgium for a multitude of reasons, with Belgium’s large amounts of coal being a big factor.

The only coal the Netherlands historically had laid in the south east, in Limburg, which is not factored into the Dutch focus tree or actual war plans as a province to be protected heavily. With the focus being laid at Holland itself.

The risk I see for countries like the Netherlands that did in fact have a decent industry but little coal is that they will become dependent upon the trade system which usually runs out of these basically essential resources such as steel. (I assume it will be a tradable resource)

I might not be too clear on my point here, but what I’m coming to as a point is: won’t this drive countries with less coal into overextending their resources or a desperate relationship with the trading system?

Sorry if I sounded pessimistic, cause I am very excited for seeing how such a change pans out, I just also have some cautions about what coal could do. Though the suggestion of refining oil into fuel and using nuclear reactors is a good one in my opinion
 
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Is there a plan to rationalise resource distribution in the game to better reflect real-life, including in focus trees, or will things like Portuguese West Africa being able to produce 1970s-80s quantities of oil in 1936 still be a thing?
 
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