Fleet Supply Model

[MichaelJanuary]

Various people have proposed supply models before, and I was tempted to bump one or two of the threads, but it also felt like resurrecting the dead

I would like to suggest the consideration of a fleet supply model somewhat similar to that used in Hearts of Iron.

Goals / Objectives:
- to penalise extreme concentrations of force
- to impose real limits on extended campaigns
- to simulate the requirement of supply lines in conventional military action
- to promote the use of mixed fleets and distributed force

Spoiler: Original text

BASICS
- Supplies are generated from solar energy, planet economies, trade.
- Supply is stockpiled at outposts and starbases.
- Maximum storage capacity for supplies is determined by level of outposts, anchorages, supply depots, etc.
- Outposts that run out of supplies, may request supplies from (friendly) neighbouring star systems.
- Excess supplies are distributed along the hyperlane network until your max network storage capacity is reached.
- Rate of transfer of supplies between star systems is influenced by shipyards, anchorages, outpost level, etc.
- Ships use up supplies based on their activity levels, status, location.
- As supply is used up and drops below given thresholds (50, 25, 10, 5) larger penalties are imposed on movement speed, ship fire rate, damage dealt and damage taken.
- Fleets/Ships are instantly resupplied to max capacity of local starbase.


AN EXAMPLE FOR HOW THIS COULD BE DONE
- Each ship uses 1 supply per day per naval capacity. So a Cruiser will use 4 supply per day, and a battleship 8 supply per day.
- Each ship can 'store' 100 days of supplies, so a corvette's max capacity is 100, and a battleship has 800 supply.
- A fleet of 10 battleships therefore, will have a capacity of 8000 supplies, and consume 80 supplies per day in normal operations.
- A fleet of 20 corvettes will have a capacity of 2000 supplies (20*100), and will use 20 supplies per day while moving, but probably 10 per day while docked (50% consumption).


SUPPLY STORAGE LEVELS
- An outpost can generate 5 supplies per day (from solar energy conversion), and import or export 100 per day from each neighbouring star system, to a maximum storage capacity of 1000 supplies.
- A starbase might generate 10 per day, and can increase this rate by building solar energy modules. It can import /export 200 per day from neighbouring star sysrtems, to a maximum of 2000 local storage capacity. Rate of import and maximum storage can be increased with appropriate modules (shipyards, anchorages, supply depots).
- Additional supply would be generated by colonised planets (in proportion to their trade value?)
- A Citadel would therefore probably have a local storage capacity of 8000 supplies, unmodified, which could be rapidly replenished by a local planet with say 200 trade value. A system with multiple planets would top up a citadel in a matter of a couple of game weeks. (A fleet of 20 battleships would have a supply capacity of about 16000).

Spoiler: Updated Text incorporating feedback from Tamwin5

FLEET SUPPLY
- Each ship in a fleet CONSUMES supply proportional to its size (naval capacity), plus a size penalty. So a corvette would consume 1 supply per day, a destroyer 2 (plus penalty), a cruiser 4 supply per day (plus penalty*2), and a battleship 8 supply per day, plus penalty * 3. If the penalty was 1 per level, a destroyer would consume 3 supply per day, a cruiser 6 supply per day, and a battleship 14 supply per day. (subject to balance). For much of the examples below we used a model approximating a supply usage of 1/3/7/15.
- Each ship in a fleet would STORE supplies for X days, where X varied per ship level. For analysis we used X=100 for corvettes, X=150 for destroyers, X=200 for cruisers, X=250 for battleships. By multiplying the hold capacity for each ship, we would get a "fleet supply limit" for the fleet.
- A fleet of 20 corvettes would have 100*1*20=2000 supply storage, and consume it at the rate of 20 per day.
- A single battleship would have 250*15=3750 supply when topped up, and consume it at the rate of 15 per day.
- A fleet of 20 battleships would have a total supply of 250*15*20= 75000, and consume it a rate of 300 per day.
- Fleets consumption would vary depending on if the fleet was docked, not docked, in combat. So a docked fleet would use 25% less supply, and if docked with a crew quarters 50% less supply, and if in combat then probably use 3x the normal rate of supply. Thus a fleet that was in combat for 30 days, would use 90 days worth of supply.
- Ships with low supply (under 20%) have their sublight speed penalised.
- Ships with critical supply (under 10%) have their fire rate reduced significantly.
- Ships with no supply (0%), have their fire rate reduced drastically, and cannot retreat.


OUTPOSTS AND SUPPLY STORAGE
- Calculation of supply storage and transfer rates is based on naval capacity, using the corvette as a unit of 1.
- We propose that an outpost (at game start) can fully resupply a single fleet of 20 corvettes, and then slowly recharge over time. Thus an outpost (with no upgrades) would have a max storage of 2000 supplies, and recharge at the rate of 20 supplies per day (100 days).
- A Citadel (level 5 outpost) would have a max storage capacity of 32,000, and recharge at the rate of 160 per day (equivalent to resupplying 160 corvettes).
- Adding Shipyard modules would boost the rate of supply generation (+10 supply per day each)
- Adding Anchorage modules would increase the storage capacity (by 4000 each).
- Thus a Citadel with 4 anchorages and 2 shipyards (for e.g.) would have a storage capacity of 48000 supply, and a generation capacity of 160+2*10=180 supply per day. This is more than enough to make a profit while supporting a fleet of 160 corvettes (160 NC) , but not quite enough to support 20 battleships (also 160 NC).


SUPPLIES FROM SOLDIER JOBS AND CIV JOBS
- if each soldier job contributed 1 supply, and each civilian job contributed 0.25 supply, a typical planet would generate about 25-35 supplies per day (added to the local outpost).
- Thus a single citadel, in a colonised system, probably with 1 or more habitats, would generate enough supply to fully support a 20 battleship fleet in normal operations, and make a profit while that fleet is docked.
- An empire, with 20 to 30 colonised planets, several habitats, a megastructure or two, and on the order of 15 to 20 upgraded starbases would be quite capable of fully supporting 3000 naval capacity worth of corvettes, or 2000 naval capacity of battleships.


TRANSFERRING SUPPLIES BETWEEN OUTPOSTS
- Each outpost can "export" 20 supply per day to a neighbour. An outpost with multiple neighbours can import from each of them.
- The transfer rate would scale with outpost level, by 20 supply per level, so a max level outpost (citadel) can export 100 supply per day.
- This can be further increased by building a naval logistics office, and the range of supply can be extended by 1 system with a hyperlane registrar.
- Thus an outpost that is short of supply, and has a hyperlane registrar, can "import" supplies from all systems within 2 jumps.


SUPPLY MOVEMENT ON THE NETWORK
- Each star system would be a node on the supply network.
- Supplies would follow the fleets.
- So wherever a fleet is docked, or is currently operational, would be the 'target' for all supply movement in the network, until the network is saturated.


TECHNOLOGIES
- Repeatable physics technology to increase storage capacity.
- Repeatable social technology to increase transfer rate between outposts.
- Repeatable social technology to increase the rate of supply generation.
- Non repeatable engineering technology (3 to 4 tiers) to improve the self-efficiency of larger ships (reduce inefficiency penalty).


OTHER CONSIDERATIONS
- Can have a diplomatic agreement to supply allied fleets (exchange supplies at border systems?)
- Ground combat units can also use supply (rate=1 supply per standard infantry unit)
- larger ships (Titan, Colossus) can either scale appropriately, or be equivalent to battleships.


FURTHER PROBABLE DEVELOPMENTS
- Ship modules to increase supply storage, reduce supply consumptions.
- Its might be necessary to implement supply convoys (transports capable of carrying 4k supplies each) if you need to resupply a fleet that is operating well away from your borders. Intercepting and destroying/capturing such fleets may be a thing.
- Calculating individual ship stats (supply storage, consumption etc. based on equipped modules), rather than a global figure linked to the hull type.

RESULTS

• Thus, at early game, a starbase and a couple of outposts can easily re-supply a couple of fleets of 20 corvettes (up to 50NC).
• By mid-game, you would need a couple of starbases or a starhold to adequately re-supply a fleet of 100-200 naval capacity.
• By end-game, you would need at least 1 citadel plus a colony or two per fleet of battleships (160NC) to keep them fully supplied.
• An empire of 20-30 developed worlds, plus habitats, 1 or 2 ecumenopolis, a megastructure and 15+ starbases, would be able to easily supply 2000NC+ worth of corvettes, or 1500NC+ of battleships.
• As long as you have a contiguous chain of outposts/starbases under your control, your fleets can be kept in reasonable supply.
• A Supply system like this can entirely replace naval capacity as a soft cap on fleet sizes.

STRATEGY OUTCOMES

• Concentrating too many ships in one region may drain that region of supplies.
• Multiple extended battles in the same region would drain that region of supplies.
• Fleets that have lots of heavy ships (battleships, cruisers) would consume supply a lot faster than fleets with smaller ships (corvettes, destroyers).
• Chokepoint systems will be more valuable, as capturing them can limit the flow of supplies through a large empire.
• The numbers above are balanced so that you can fight an intense war with all/most of your fleet in a small region of space (5-10 star systems) for at least 1 year, before draining the region of all supplies. The more spread out the conflict, the longer the supplies will last.
• The numbers are also balanced around 1NC=1Corvette, with heavier ships using up supply faster.
• Gateways would facilitate easier distribution of supply through your empire.

 

[Tamwin5]

A couple of things:

Supply should increase per level of starbase. A citadel gives more than a starhold. 10 per level sounds reasonable.

The starbase module to increase supply should be the anchorage. The fleet logistics office should probably allow more supply to imported or exported.

With your model, a corvette would have the same operating time as a Battleship. Heavier classes of ship should have a greater maximum supply. The supply of a fleet should be even across the entire fleet, so mixed fleets allow smaller ship sizes to last longer. I think 50% more per size. So corvettes have 100, Destroyers have 300, Cruisers have 800, and Battleships have 2000. Titans would only have 2000, but still use up 16 per month. That was a Corvette can last 100 days, a Destroyer 150, a Cruiser 200, and a Battleship 250.

There should be an Auxiliary slot to increase maximum supply by a significant amount, perhaps 50%?

Supply penalties should only start kicking in at under 10% supply. Perhaps fleets can have a stance of "conserve supplies" that gives them a debuff in exchange for less supply usage. recovering from that should take at least a month. Ships with 0 supply should probably never disengage, to make getting caught with no supply allow a fleet to be wiped out.

For planets, I dislike trade value being supply. Instead make it be the number of building slots. Soldier jobs, or any other job that generates naval capacity, would give a bonus on top of that.

The stockpile starbase module and planet building should increase the max stored supply for a system.

Occupied systems/starbases/planets should have the supply they generate be reduced by 20%. This is mainly for flavor reasons, but it also makes invasions harder. Recently conquered systems would keep that penalty for a year or three, to make total wars be similar.

Supplies being passed from one system to another should be added to trade routes in each system for piracy values. If a starbase is in combat, it can't pass or receive supplies( I was tempted to make this happen if any hostile ship was in system, but that would make it too easy for a single corvette to jump to the edge of a Bastion and cut off supply).

 

[MichaelJanuary]

@Tamwin5 everything you said is aligned with my thinking. Thank you for your considered response.

Happy to vary how supply generation is calculated.

Happy for larger ships to have more storage capacity and more operational days. Also in agreement that supply transfer between systems should only be blocked by outposts being captured or in combat.

I like your suggestion that captured bases should operate at lower than full capacity.

For UI/Visualisation purposes I was thinking that the supply level of a fleet could be visualized by a progress bar on the fleet icon, or the fleet icon could be colour coded (green/yellow/red).

The 1 area where I might vary from your suggestions is the point at which low supply malus kicks in. I would probably go for a minor malus at 25% (short rations) and a medium to severe malus at 10% (out of ammo) and finally a crippling malus at 0% (out of fuel).

 

[Tamwin5]

@Tamwin5 everything you said is aligned with my thinking. Thank you for your considered response.

Happy to vary how supply generation is calculated.

Happy for larger ships to have more storage capacity and more operational days. Also in agreement that supply transfer between systems should only be blocked by outposts being captured or in combat.

I like your suggestion that captured bases should operate at lower than full capacity.

For UI/Visualisation purposes I was thinking that the supply level of a fleet could be visualized by a progress bar on the fleet icon, or the fleet icon could be colour coded (green/yellow/red).

The 1 area where I might vary from your suggestions is the point at which low supply malus kicks in. I would probably go for a minor malus at 25% (short rations) and a medium to severe malus at 10% (out of ammo) and finally a crippling malus at 0% (out of fuel).

Considering there isn't morale for ships, what would have the "short rations" malus be? Under 10% could be a Fire rate -25%, and then at 0 go with fire rate -75%, sunlight speed -50%, and disengagement chance -100%.

Another thing that should be added alongside supply is the ability to emergency FTL when not in combat and not trapped behind borders. Have the amount of supplies they have factor into damage/destruction rates of ships.

Should using a jump drive require an amount of supply?

 

[MichaelJanuary]

Should using a jump drive require an amount of supply?

I thought about it, but lesned towards no. Hyperlane cooldowns and jump drive malus is alrdy penalising. No need for it to cost additional supply too.

 

[Tamwin5]

I thought about it, but lesned towards no. Hyperlane cooldowns and jump drive malus is alrdy penalising. No need for it to cost additional supply too.

It could be lessened. The question is whether having the jump use supplies is interesting/good gameplay. Once the core types of penalties and flavor is determined, numbers can be balanced.

 

[MichaelJanuary]

A knockon effect of a supply model as descrubed above is that battleships would be expensive to operate, consuming supplies at 8x the rate of corvettes, and with their reduced speed will have a shorter operational range.

Even with @Tamwin5's suggestion of increased storage space for larger ships, this will cover operational range but not cost of operations. It would make better strategic sense to keep most of your battleships docked, except for major battles, and rather use cheaper fleets (cruisers, destroyers, corvettes) for other offensive operations.

A natural effect of a large scale war where you are operating multiple fleets of battleships would be that your empire is just unable to generate enough supplies to sustain operations. War exhaustion in its purest form.

 

[Tamwin5]

A knockon effect of a supply model as descrubed above is that battleships would be expensive to operate, consuming supplies at 8x the rate of corvettes, and with their reduced speed will have a shorter operational range.

Even with @Tamwin5's suggestion of increased storage space for larger ships, this will cover operational range but not cost of operations. It would make better strategic sense to keep most of your battleships docked, except for major battles, and rather use cheaper fleets (cruisers, destroyers, corvettes) for other offensive operations.

A natural effect of a large scale war where you are operating multiple fleets of battleships would be that your empire is just unable to generate enough supplies to sustain operations. War exhaustion in its purest form.

Actually, Battleships have the same rate of supply drain as 8 corvettes would. Higher ships could be made supply inefficient as a balance to having more capacity. I would likely either do this as 1/3/7/15 or 1/3/9/27, or double the supply production of everything and make it 2/5/10/25 or 2/5/15/35.

(as a separate side note, this suggestion is good enough you should put it in your signature)

 

[MichaelJanuary]

Actually, Battleships have the same rate of supply drain as 8 corvettes would.

Quite right ... thanks for pointing that out.... with a flat supply rate it just becomes inefficient to use unnecessarily large fleets. The makeup of the fleet is irrelevant unless there is a scaling supply cost for larger ships.

 

[Tamwin5]

Actually, Battleships have the same rate of supply drain as 8 corvettes would. Higher ships could be made supply inefficient as a balance to having more capacity. I would likely either do this as 1/3/7/15 or 1/3/9/27, or double the supply production of everything and make it 2/5/10/25 or 2/5/15/35.

Let's do some modeling to see how the numbers work out.

Using Models 1, 2, 3, and 4, for 10 Battleships of supply you could have 150(187.5%), 270(337.5%), 125(152.625%), or 175(218.75%) Corvettes.

I think Corvettes being more than 3 times as supply efficient as Battleships isn't what we want, so Proposal 2 is out. I think 1 or 3 is the way to go. They both have the same ratio of Destroyers to Battleships (1 Battleship = 5 Destroyers), but Prop 3 has cruisers being more efficient than the rest of the trend. Prop 1 is "clean" in that each level is the last level times 2 plus 1, but Prop 3 is "clean" in that everything uses nice numbers.

For the below math I will use Prop 1 (1/2/7/15) since it makes the base upkeep of supply 1, which makes math easier.

Let's figure out how much supply an empire might generate. If you have a Star Fortress Bastion supported by a Star Fortress anchorage, thats 80 supply just from the two starbases. Lets say that the empire has 7 starbases and 20 systems. If those are StarHolds, thats 240. If they are star fortresses, it's 310. Enough to support 20 Battleships or 300 Corvettes, with only a moderately sized mid-game empire and fully ignoring supply from planets. From those numbers I'm inclined to say that anchorages shouldn't increase supply generation by much, or not increase it at all. The main issue is going to be funneling supply to where you need it.

Let's say you have a chokepoint Bastion. If you have an anchorage behind it, or multiple system connecting to it, then supply is limited by the Bastion's import. The Citadel itself gives 40 supply. If starbase import is flat at 200, it can only support 240 supply, or 8 Battleships. If it's 100 per starbase level, then it can support 540, or 36 Battleships. Let's say that the naval Logistic office gives +200 potential import/export. Using a valuable building slot lets you get up 740 supply, or nearly 50 Battleships. 400 naval cap. For a max level starbase, that seems pretty good, balance wise.

Say you have some random outpost. 5 supply generation, maximum of 100 import. It can support only 7 Battleships, or 56 fleet capacity. If you use corvettes, you can get 105 though. Considering this is what things will look like early game, it brings up a concern. During the early game, there will be no troubles getting supplies to your entire fleet, assuming you have a route of outposts. I think that the base rate of Starbase supply import/export should be 50 per level, and then there can be 5 techs that increase it by 10 per level each. It could also start at 25 and be 15 per level each, or 20 and then 4 techs of 20. The first one is cleaner and fits with the 20% bonus trend, but the second is better balance imo, and the third a compromise. It would fit with either physics or society, but I think it should be flavored to physics as it is the tree with the least techs.

---

Now let's look at storage. I'm going to keep the daily operating time ratios that I came up with before (100, 150, 200, 250 days), and scale them with the increased supply usage. Now you have a storage of 100/450/1,400/3,750 per ship. Since those numbers are so close to whole ones, let's make it be 100/500/1,500/4,000 so math is clean. A fleet of 20 corvettes only needs to stop by 2 outposts to max out, while even just 1 battleship would need to hit up 40 in order to be filled. This is also interesting in the fact that a couple of larger ships will greatly enhance the length a fleet of corvettes can last. 60 corvettes have 6,000 capacity, and use 60 per day to last a total of 100 days. A fleet of 40 Corvettes and 5 cruisers has 11,500 (7500+4000) capacity, and uses 75 (40+35) per day to last 153 days.

I'm curious how you got a value of 8000 storage for citadels. 1000 for outpost, 2000 for Starport, 4000 for Starhold, 6000 for Star Fortress, 8000 for Citadel? I might go 1k, 2k, 4k, 8k, 15k. Considering that a Battleship holds 4k each, it really doesn't seem like much. If every Anchorage gives a capacity of +2000, then a max level starbase could either have 20k or 27k storage, enough to fill up 5 or 6.75 Battleships. If you have 160 naval cap of Battleships, You'd need to stop at 4 different max level anchorages to fully stock up. If you have that Battleship fleet socked in that system waiting, pulling maximum supply, it will take 50 days to fully restock (using the 50% supply reduction when docked). This means that you can't really just stop by your anchorage and resupply, but instead have to just dock up for a bit to lower supply usage and let it trickle in.

Imo, I'd buff these storage numbers up substantially. An outpost gets 1k, a Starbase gets 10k, then +10k every level up to 40k Citadel. Every anchorage gives 5k, so a citadel anchorage gives you 100k storage. Enough to fully resupply 25 Battleships, or a thousand corvettes. By making storage much larger, it means that production of supply can be smaller, so when your fleets are active you have a net drain on supply. Having a net drain on supply is required to have it burn down over a war, ofc, which is a very good mechanic to have. Assuming you have a a total supply production of 200 supply with all your ships docked, it would take 4 years to completely fill up 3 Citadel Anchorages. Considering that you both would have more storage and also not use up all your supply in a war, that seems like a good threshold for recovery times. Similarly, if you are running a deficit of 200 supply, those 3 citadel anchorages can fuel that for 4 years.

---

A couple of other things. I think that just getting 50% supply reduction for being docked at any station is a bit much. I'd make it be 25% for docked, and 25% for the crew quarters building. This makes it much more important to try and keep your fleets docked at starbases with crew quarters. When a ship is being built, it should drain supply, so that it spawns with full supply (or atleast, non-zero supply). Queuing up 6 Battleships will be a massive supply drain. To prevent ships from suddenly running out of supplies in friendly space, and as a quality of life improvement for players, when a ship is in a friendly system its upkeep should be covered by that starbase, if able. In order for supply to be replenished it would still have to dock, and if the starbase is in battle then it would be unable to import supply.

Supply from planets should be based on the number of pops with military service enabled. Perhaps 1 per 4 pops with full military service, 1 per 5 pops of soldiers only, and 1 per soldier job? A planet of 60 pops would give 12/15 supply. A planet of 30 pops with three fortresses would give 15/16 supply. 400 pops, 30 systems, and 10 star fortresses would give a total of 650 supply per day, enough to run 43 Battleships clean, or 80 docked (344 or 640 naval cap). If you went Corvettes you could go for 650 corvettes direct, or more than 1000 docked. Cruisers would be With a large enough empire, you would likely have issues moving supply from one end to the other, considering that an outpost can only move 100 supply through it.

@MichaelJanuary Thoughts? This help you understand values for your proposed system?

 

[MichaelJanuary]

I'm curious how you got a value of 8000 storage for citadels

Mistake. I meant to go 1k/2k/4k/8k/16k and skipped a level. So a citadel according to my original logic was 16k base supply (before techs and upgrades). That does seem a bit low if we apply the inefficiency rule for larger ships.

A couple of other things. I think that just getting 50% supply reduction for being docked at any station is a bit much. I'd make it be 25% for docked, and 25% for the crew quarters building. This makes it much more important to try and keep your fleets docked at starbases with crew quarters.

Agreed.

K, you've forced me to take my haphazard thinking and start developing some spreadsheet models.

The basic premise for supply usage, generation, transfer and storage follows the game's inherent precept on Naval Capacity. i.e., each ship level has double the naval capacity of the prior level. (1/2/4/8/16) i.e, binary escalation.

So we could start out with the following basics:
- Corvette uses 1 supply per day
- Outpost can generate 10 supply per day
- Outpost has a maximum storage of 2000 supplies (unmodified)
- Outpost can transfer 100 supply per day to a neighboring outpost.

Then double this for every level of ship or outpost. (binary escalation) (same as naval capacity)

The result would be that a naked Citadel would generate 160 supply per day, Have 32k storage, and a transfer/throughput of 1600 supply per day.
(The bottleneck in your empire would be undeveloped outposts, that would have a base throughput of 100 per day).
(How to move supply rapidly through your network of star systems? Transports? Convoys?)


We can also apply the following rules:
- Each ship level is 25% LESS efficient in supply usage than the previous level.
- An anchorage increases supply storage by 4000.
- A shipyard generates 20 supplies per day.
- Each soldier job in a system adds 1 supply per day.
- Each (employed?) pop in a system adds 0.25 supply per day.

This would translate into the following:
- A corvette would use 1 supply per day (undocked), with a hold capacity of 100 supplies (100 days operations)
- A battleship would use 15.6 supplies per day, with a hold capacity of 4000 supplies (slightly more than 250 days operations)
- A Citadel with 6 anchorages would be able to store 56,000 supplies (enough to instantly resupply 14 battleships, or 560 corvettes)
- A Citadel with 6 shipyards would be able to store 32,000 supplies, but would generate a total of (160 base + 120 bonus = 280 supplies per day) (equivalent of 18 battleships consumption)
- A Star System with 100 pops and a couple of fortresses would probably add about 30-40 supply per day to the local outpost. (I would probably like to push this closer to 100 per day for a fully developed planet).

These aren't exactly the same numbers you used, but roughly the same principals are applied. The major bottlenecks then becomes the ability to move supply around in your network, and the total supply capacity of the network.

I would also advocate for the following tech equivalents:
- Physics Tech to increase storage capacity - Multi Dimensional Storage - +10% per level to hold capacity of outposts and ships.
- Social Tech to increase supply generation - Logistics - +10% supply generation per level.
- Engineering Tech to increase ship design efficiency - 5% per level - reduces the penalty imposed on larger ships. (i.e., instead of a 25% penalty per level, you could reduce it to 20% per level, or 15% per level).

- Buff Existing Tech - Hyperlane Drive - +20% transfer rate per hyperdrive level.
- Buff Existing Module - Hyperlane Registry - +100 transfer rate to outposts with a hyperlane registry.

Additional Point of Clarity:
For convenience, I would not require ships to be docked to resupply. Ships would resupply on
A) Being docked.
B) While charging up hyperdrives they would be topped off by the local outpost.
C) After combat, in a friendly system, the fleet would be immediately topped off by the local outpost.
D) On fleet merge, and after each jump, and after combat, all ships supplies would be re-balanced.

I have not yet considered the impact of allies, federation members, defensive pacts, etc. There would have to be an exchange mechanism to compensate allies for supplies.

 

[Tamwin5]

K, you've forced me to take my haphazard thinking and start developing some spreadsheet models.

The basic premise for supply usage, generation, transfer and storage follows the game's inherent precept on Naval Capacity. i.e., each ship level has double the naval capacity of the prior level. (1/2/4/8/16) i.e, binary escalation.

So we could start out with the following basics:
- Corvette uses 1 supply per day
- Outpost can generate 10 supply per day
- Outpost has a maximum storage of 2000 supplies (unmodified)
- Outpost can transfer 100 supply per day to a neighboring outpost.

Then double this for every level of ship or outpost. (binary escalation) (same as naval capacity)

The result would be that a naked Citadel would generate 160 supply per day, Have 32k storage, and a transfer/throughput of 1600 supply per day.
(The bottleneck in your empire would be undeveloped outposts, that would have a base throughput of 100 per day).
(How to move supply rapidly through your network of star systems? Transports? Convoys?)


We can also apply the following rules:
- Each ship level is 25% LESS efficient in supply usage than the previous level.
- An anchorage increases supply storage by 4000.
- A shipyard generates 20 supplies per day.
- Each soldier job in a system adds 1 supply per day.
- Each (employed?) pop in a system adds 0.25 supply per day.

This would translate into the following:
- A corvette would use 1 supply per day (undocked), with a hold capacity of 100 supplies (100 days operations)
- A battleship would use 15.6 supplies per day, with a hold capacity of 4000 supplies (slightly more than 250 days operations)
- A Citadel with 6 anchorages would be able to store 56,000 supplies (enough to instantly resupply 14 battleships, or 560 corvettes)
- A Citadel with 6 shipyards would be able to store 32,000 supplies, but would generate a total of (160 base + 120 bonus = 280 supplies per day) (equivalent of 18 battleships consumption)
- A Star System with 100 pops and a couple of fortresses would probably add about 30-40 supply per day to the local outpost. (I would probably like to push this closer to 100 per day for a fully developed planet).

These aren't exactly the same numbers you used, but roughly the same principals are applied. The major bottlenecks then becomes the ability to move supply around in your network, and the total supply capacity of the network.

A big design principle that needs to be figured out is how much supply relative to naval capacity you want. Should your production of supply basically always be sufficient to run your fleet, and the issue to getting supplies to your ships? Should your net supply drain during war time, but then recover when at peace? Should your supply be as much of a cap as naval capacity? I think the threshold should be a drain during war, but at peace positive even with naval capacity of battleships. An empire constantly at war might feel a push to use smaller ships with a lower naval capacity, or quickly push on the offensive to try and capture systems for supply. (on a side note: Capturing a system should remove any stored supply. This is both to nerf snowballing, but also make raiding ships useful to hit supply depots.

Another thing to consider in terms of design philosophy is what the ratio of supply gain/loss to total storage should be. How long should it take to fully refill your stockpiles? How long should those stockpiles last during war? An outpost with 5 generation and 2k supply takes just over a year to be filled up. A 6 shipyard citadel with 280 production and 32k storage would take 115 days, 4 months. A 6 anchorage citadel with 160 production and 56k storage would take just under a year to fully fill up. And this is just with starbase ad outpost production, completely ignoring planet production. If you have 400k storage (8 citadel max anchorages, or 13 default Citadels, or 200 outposts), that will last roughly 25k Battleship days. 1 Battleship for 70 years, or 70 battleship for 1 year. Having a full swing from full to empty in about a year feels far too short.

I think the problem here is understanding of scale, and the fact that supply is calculated daily and not monthly. You are picking numbers that feel right to you, based on stellaris. Resources for everything else in Stellaris are calculated monthly, not daily. For this reason, the storage of starbases should probably be increase by a factor of 10-30. I also dislike the binary escalation of starbases, mainly because the progression of starbases is a linear +2 modules +1 buildings(only health and armor doubles, cost more than doubles). Probably my bias also factors, but I do prefer my suggestion of 10k per level and 5k per anchorage.

If you wanted to push supply generation up to about 100 per planet, just make every pop (with military service) generate 1 supply. This would have the added benefit of making supply a fully whole number system. If this was done, you would also have to shift the ships back to whole number supply usages, of course. Clean numbers are more useful and more intuitive, and since we are inventing the balance as we go being easy to understand is key. So as much as the every ship being 2.5 times the supply of the last is nice, I'd go for the whole number 2x+1 I had.

I do like the idea of shipyards generating supply. It means that you'd likely want multiple shipyards at each end of your empire, helping fuel the front lines. One thing to keep in mind is that a citadel shipyard can support 8 more battleships than a normal shipyard. If 8 battleships has more firepower than changing those slots to gun turrets, then the optimum defense is shipyards at borders, which feels kind of off. Values might have to be adjusted with that in mind.

I would also advocate for the following tech equivalents:
- Physics Tech to increase storage capacity - Multi Dimensional Storage - +10% per level to hold capacity of outposts and ships.
- Social Tech to increase supply generation - Logistics - +10% supply generation per level.
- Engineering Tech to increase ship design efficiency - 5% per level - reduces the penalty imposed on larger ships. (i.e., instead of a 25% penalty per level, you could reduce it to 20% per level, or 15% per level).

- Buff Existing Tech - Hyperlane Drive - +20% transfer rate per hyperdrive level.
- Buff Existing Module - Hyperlane Registry - +100 transfer rate to outposts with a hyperlane registry.

Additional Point of Clarity:
For convenience, I would not require ships to be docked to resupply. Ships would resupply on
A) Being docked.
B) While charging up hyperdrives they would be topped off by the local outpost.
C) After combat, in a friendly system, the fleet would be immediately topped off by the local outpost.
D) On fleet merge, and after each jump, and after combat, all ships supplies would be re-balanced.

I have not yet considered the impact of allies, federation members, defensive pacts, etc. There would have to be an exchange mechanism to compensate allies for supplies.

I wouldn't add a tech to reduce the penalty of larger ship sizes. The reason for this is that supply upkeep is counteracted by the fact that they have a greater storage and longer range. The ratio should be maintained, for that balance reason. I'm not opposed to a tech buffing that, as long as it buffs all ship classes evenly. Considering that one of the main reasons for adding a supply system is to penalize extreme concentrations of force, this brings up a concern involving tech. If there is a repeatable tech that decreases the supply cost of ships, increases supply generation, or increase supply maximum movement, then it risks a high tech empire being OP. A high tech empire already gets more efficient ships, allowing them to make better use of the same supply, so allowing them to also get too much more supply as well wouldn't be balanced.

I think that a physics tech to increase the hold capacity by 20% would be good. 100 days really isn't that long for a ship to last, and late game you may want to run extended campaigns, either to fight FEs or combat the crisis. A society tech to increase supply generation is also good, but it needs to be balanced in tandem with the base supply generation from outposts, starbases, and planets. If supply is higher than usage during war, it removes a vital aspect of a supply system. Perhaps only 1 or 2 techs to increase supply generation, to keep them more interesting, and easier to use whole numbers with.

The amount of supply that can be moved from one system to another should not have a repeatable, for the reason above about concentration of force. Starbase supply storage and ship supply storage should probably also have repeatables, although if they are the same tech or separate is something to consider. A supply generation repeatable is something I'm unsure on, as the player will likely still be growing pops in the endgame, and so increasing supply that way.

For the Hyperlane registrar, instead of buffing the local import/export, what if it instead buffed the import/export of adjacent systems? That way you can use a Hyperlane registrar every 3 systems to maintain a route of 200 supply, or every other system for a route of 300 supply. That way you can use the logistics office for concentrated supply needs, or the registrar for spread out supply needs. You could also just remove the logistics office from affecting supply import/export.Having the Naval Logistics office affect supply gives it a reason to exist on a front line starbase, which is an interesting strategic decision.

Late game, we also need to consider the impact of gateways. Gateways will eliminate cross-empire Bottlenecks, the only limits will be local supply import, and total empire supply production. It will also allow a player to keep a large fleet active, by jumping between several systems, each importing supply, effectively allowing the player to double, triple, or quadruple their effective local supply, but at the risk of being ambushed or having a starbase lost while they were somewhere else. This is a reasons to have ships only filling to fully supply when docked, as gateway travel time is instant. As a compromise, they could resupply on getting within a certain distance of the outpost, so just clicking on the outpost wouldn't cause your ship to sit there forever not being supplied. Or maybe a tick upwards at the same rate that you would normally tick downwards? A corvette passively gains 1 supply per day in friendly territory, a destroyer gains 3, etc.

For a fleet, I think it would just not track individual ships. Fleet upkeep is equal to 1x number of corvettes, 3x number of destroyer, etc, and Fleet storage is equal to 100x number of corvettes, 500x umber of destroyers, etc. It would reduce calculations by a lot, and have the same effect.

One last thing that I realized wasn't touched on is the strategic coordination center. This should 100% have some effect on supply. Maybe it increase import/export by 100, per level, across your entire empire? On a maxed out Citadel it would go from 700 to 1000, on a Radom outpost it would go from 100 to 400. I like the idea of it being a way to buff your entire empire, especially outposts, but I dislike how much of a difference it could make on Bastions or choke points. I think this needs some more thinking on.

 

[MichaelJanuary]

Everything ties back to naval capacity. An empire with a naval cap of 1000 should be able to comfortably field 1000 corvettes, even comfortably field a mixed fleet as long as they don't use it wrecklessly, but should be supply limited if they field 1000 naval cap consisting entirely of battleships.

They can do it, but would have to be sure they can win early victories and manage their fleet operations to conserve supply. Defensive ops would favor battleship heavy fleets, and if you use battleships offensively you cant throw them around, youd have to use them with purpose.

So for e.g. an early game outpost would be able to resupply 20 corvettes from scratch then slowly recharge. A citadel therefore would be able to recharge 160 corvettes, more with anchorages and shipyards and techs. However if your 160 point fleet consists of 20 battleships even a citadel should come up short.

Not a fan of Infinitely repeatable techs. Happy to have 3 or 4 tiers of tech to reflect advanced empires having more self sufficient ships, but not infinitely so.

 

[Tamwin5]

Everything ties back to naval capacity. An empire with a naval cap of 1000 should be able to comfortably field 1000 corvettes, even comfortably field a mixed fleet as long as they don't use it wrecklessly, but should be supply limited if they field 1000 naval cap consisting entirely of battleships.

They can do it, but would have to be sure they can win early victories and manage their fleet operations to conserve supply. Defensive ops would favor battleship heavy fleets, and if you use battleships offensively you cant throw them around, youd have to use them with purpose.

So for e.g. an early game outpost would be able to resupply 20 corvettes from scratch then slowly recharge. A citadel therefore would be able to recharge 160 corvettes, more with anchorages and shipyards and techs. However if your 160 point fleet consists of 20 battleships even a citadel should come up short.

Not a fan of Infinitely repeatable techs. Happy to have 3 or 4 tiers of tech to reflect advanced empires having more self sufficient ships, but not infinitely so.

See, I think even mixed fleets should worry about supply. Supply should be something that functions like actual war exhaustion: you simply are running out of stuff, and you either need to dock your fleets and let your opponent have free reign for a while, or peace out with what you have gotten. Atleast for empires who are focusing on building up a big fleet. At the end of the day though, this is a game design decision.

A star fortress anchorage adds 36 fleet cap. 36 fleet cap is 4.5 Battleships or 36 corvettes, which use 67.5 and 36 supplies respectively. If a Star Fortress provides more than that amount of supplies(like your decimal expansion suggestion, which gave 80 for a star fortress), then someone who is going full out for maximum fleet size will end up with MORE supplies, not less. Also those ships can be docked for half supply upkeep.

Actually, defensive ops are better suited to Corvettes. For defense you want to just sit a fleet at a chokepoint, and let the enemy come to you. The limit to how many ships you can park is the local supply import limit, which means that efficient ships, like corvettes, will be able to be the most densely packed. You can also keep the ships docked at the starbase, and get twice as many as what the import cap would support normally. Battleships would be best for attacks, where you will be going for a while through outposts and other low supply areas, but still need the firepower to crack the starbases you come across. The 250-500 (tech depending) day storage would let you conquer a significant chunk of territory, and the time where you need to retreat is likely paired with having taken hull damage and needing to repair as well. Corvettes are best used in small groups, quickly sniping a couple of outposts so they can then support themselves. Or perhaps use Destroyers, with L slot bows and PD afts, as outposts only have a single G slot for defense. If you are trying to break a defensive starbase that has a high fleet power or is backed by a fleet, you can build ships to counter, mass them in a couple of different systems (to maintain maximum supply), then fly them all together to attack, and once you've taken it retreat excess fleets until you are within supply.

Repeatable techs are a function of the way Stellaris works. There are techs to get more naval cap, larger fleet sizes, and more starbases. Adding a supply system that is core for warfare and techs for it, but then not having any repeatables is a little odd. The key thing is that it isn't infinite. The techs would just allow ships to spend longer on their own supply, or starbases to have a larger pool to drain from.

Something that I forgot to cover in my last post: Federations, or people allied due to a war, will be able to freely use and share supply between them. There perhaps should be a diplomatic option to allow their fleets to use your supply, so that they can pass through your systems or fight someone you don't like.

 

[MichaelJanuary]

Only a relative handful of techs in stellaris are infinitely repeatable. Most techs only have 3 to 5 tiers. Given you already have a repeatable tech that gives you +1 starbase, this alone will increase your network supply caoacity.

I can live with a repeatable +5% increased supply storage tech, but probably not repeatable techs for supply generation or supply transfer. These should have no more than 3 to 5 tiers.

As the game progresses, your planets, habitats, megastructures and growing population will all be contributing to your supply generating capacity. A single citadel with 6 anchorages and a couple habitats in the local system would be quite capable of supporting about 300 to 400 naval capacity on it's own depending on the fleet composition.

A combination of gateways and strategically placed starholds with hyperlane registrars will provide you with means of rapidly moving supply through your empire .... on the order of 800+ supply per day before techs and bonuses.

Given that a fleet of 20BBs in enemy territory and in near constant combat (unlikely) will consume about 900 supply per day, a single such supply connection is sufficient to infinitely supply 1 such fleet and still keep the local forward base topped up. Two such fleets might see an odd dip in local supply, and three such fleets will be a net supply drain, unless 1 or 2 of the three is kept docked most the time. Bear in mind that the model encourages the use of more efficient ships, so having 1 fleet of 20BBs and 2 or 3 fleets of smaller ships will be a lot less costly in terms of supplies. Its concentrating too many battleships that will kill you in the long term.

I will run some numbers later to model scenarios on different empire sizes and what their likely supply levels would be.

 

[Tamwin5]

Only a relative handful of techs in stellaris are infinitely repeatable. Most techs only have 3 to 5 tiers. Given you already have a repeatable tech that gives you +1 starbase, this alone will increase your network supply caoacity.

I can live with a repeatable +5% increased supply storage tech, but probably not repeatable techs for supply generation or supply transfer. These should have no more than 3 to 5 tiers.

As the game progresses, your planets, habitats, megastructures and growing population will all be contributing to your supply generating capacity. A single citadel with 6 anchorages and a couple habitats in the local system would be quite capable of supporting about 300 to 400 naval capacity on it's own depending on the fleet composition.

A combination of gateways and strategically placed starholds with hyperlane registrars will provide you with means of rapidly moving supply through your empire .... on the order of 800+ supply per day before techs and bonuses.

Given that a fleet of 20BBs in enemy territory and in near constant combat (unlikely) will consume about 900 supply per day, a single such supply connection is sufficient to infinitely supply 1 such fleet and still keep the local forward base topped up. Two such fleets might see an odd dip in local supply, and three such fleets will be a net supply drain, unless 1 or 2 of the three is kept docked most the time. Bear in mind that the model encourages the use of more efficient ships, so having 1 fleet of 20BBs and 2 or 3 fleets of smaller ships will be a lot less costly in terms of supplies. Its concentrating too many battleships that will kill you in the long term.

I will run some numbers later to model scenarios on different empire sizes and what their likely supply levels would be.

My proposal had the techs boost UP to the 100 import/export for outposts and max of ~800 for Citadels.

But even with those techs, that's only for areas that have a proper supply chain of starbases. The moment your fleet crosses 1 outpost, your are down to 100 supply import(200 with adjacent registry), even if there is a starbase on the other side. It's enough to support a small to medium sized Battleship fleet(50 to 100 naval cap, 6 to 13 BBs), or a large corvette fleet.

While the insides of your empire will likely be designed to allow free flow of supplies, the empires you are invading likely won't be. It may in fact become strategy to have a buffer outpost or two to limit the supply of any enemy invading. Let's say you have 100 naval cap fleet of Battleships, twice what the local network can support. Even with no storage techs, you can last for 500 days just on imported supply. And if you ever capture a starbase, especially a shipyard, or a planet, that number will be extended further.

So 100 is a good cap to have, imo. It still allows relatively large fleets to operate with only moderate time limits. How did you get 900 supply from 20 BBs? I get 300 supply usage. Are you assuming that 2/3 of the time they are in hostile territory, and thus not getting resupplied? Honestly, probably accurate.

Going back to the top of your post, there are actually 25 different repeatable techs. More than just a handful. I also stated that a tech to increase supply import/output was a bad idea, for balance reasons. You do make good points about the repeatable starbase tech already helping build supply. So just 1 repeatable for storage sounds good. Engineering and society already have a ton of repeatables, physics only has 5.

 

[MichaelJanuary]

So 100 is a good cap to have, imo. It still allows relatively large fleets to operate with only moderate time limits. How did you get 900 supply from 20 BBs? I get 300 supply usage.

300 supply is right in normal movement, but I assumed 3x supply consumption in combat. Hence a max of 900 consumption per day.

As for transfer rates, yes it should be a bottleneck. My base transfer rates and escalation is probably too high.

If we start at 20 per day for an outpost (20 Corvette fleet), and increase by 20 for each level of outpost, that would put a citadel at 100 per day. Then modules (logistics office, registrar) and techs can buff that further. My gut says a standard transfer rate at end game should be close to160 per day, but my head feels that is a bit low and it should be closer to 250 per day, being the typical naval capacity of a late game fleet.

A forward base (citadel) on a choke point with 2 internal nodes behind it would probably generate about 200 to 300 supply per day, and be capable of importing 2x250 supply per day max. This would mean it can resupply about 800 naval capacity in normal ops. On the low extreme, if the two supporting nodes were empty star systems with only an outpost, it would only be importing about 40 supply per day, reducing its support capacity to 1 end game fleet.

If you captured 4 or 5 systems in succession with no starbases, your fleet would be at the end of a chain that can only feed them about 20 to 40 supply per day. Capturing developed systems with upgraded starbases would become critical. There would have to be mechanisms to limit players from engaging in scorched earth tactics, like instantly downgrading all their starbases as fleets approached.

It brings us back to basic questions. How much fleet capacity should 1 fully developed star system be able to support? If we define 'fully developed' as 1 colony with 100+ pops, probably 1 habitat and at least a starhold, then such a system should probably support 160 to 200 naval cap.

A less rich system ... 1 colony of about 70 pops, with no other infrastructure to speak of, would just be a way station. If it only has an outpost, it might generate 70 to 100 supply per day, of which only 20 per day can be contributed to the empire, and the difference is lost(?) Once local storage is exceeded.

This would probably create pressure to have the ability for supply ships to be able to transfer supply from such starbases from time to time.

Also need to consider that ground troops will also need to be supplied, and ground combat will also be a costly supply operation.

 

[Tamwin5]

300 supply is right in normal movement, but I assumed 3x supply consumption in combat. Hence a max of 900 consumption per day.

As for transfer rates, yes it should be a bottleneck. My base transfer rates and escalation is probably too high.

If we start at 20 per day for an outpost (20 Corvette fleet), and increase by 20 for each level of outpost, that would put a citadel at 100 per day. Then modules (logistics office, registrar) and techs can buff that further. My gut says a standard transfer rate at end game should be close to160 per day, but my head feels that is a bit low and it should be closer to 250 per day, being the typical naval capacity of a late game fleet.

A forward base (citadel) on a choke point with 2 internal nodes behind it would probably generate about 200 to 300 supply per day, and be capable of importing 2x250 supply per day max. This would mean it can resupply about 800 naval capacity in normal ops. On the low extreme, if the two supporting nodes were empty star systems with only an outpost, it would only be importing about 40 supply per day, reducing its support capacity to 1 end game fleet.

If you captured 4 or 5 systems in succession with no starbases, your fleet would be at the end of a chain that can only feed them about 20 to 40 supply per day. Capturing developed systems with upgraded starbases would become critical. There would have to be mechanisms to limit players from engaging in scorched earth tactics, like instantly downgrading all their starbases as fleets approached.

It brings us back to basic questions. How much fleet capacity should 1 fully developed star system be able to support? If we define 'fully developed' as 1 colony with 100+ pops, probably 1 habitat and at least a starhold, then such a system should probably support 160 to 200 naval cap.

A less rich system ... 1 colony of about 70 pops, with no other infrastructure to speak of, would just be a way station. If it only has an outpost, it might generate 70 to 100 supply per day, of which only 20 per day can be contributed to the empire, and the difference is lost(?) Once local storage is exceeded.

This would probably create pressure to have the ability for supply ships to be able to transfer supply from such starbases from time to time.

Also need to consider that ground troops will also need to be supplied, and ground combat will also be a costly supply operation.

I was thinking start at either 50 per starbase level, and 5 techs giving +20%, or start at 20 per level and 4 techs giving +100%.

A standard outpost transfer of 100 later game seems reasonable. With Corvette fleets you mainly worry about supply lines being cut, with Battleship fleets you worry about getting enough supply, but don't have to worry as much. If the strategic coordination center is available as a late game option, it will then suddenly open up large offensive pushes and further ranging campaigns.

For your forward base example, remember that the limit is for both export AND import. The bottleneck will always be the station where the ships are docked, unless it only connects to outposts.

You'd only need 2 systems with outposts to drop to minimum supply. If you don't have a Hyperlane register, it only takes 1. Perhaps outposts get a buff to import/export just from friendly adjacent starbase? That way a 1 outpost or 2 outpost block would only cause a small dip in supply capacity. Considering how much of an investment starbases are, I think scorched earth tactics are fine, or atleast not worth worrying about too much. Scorched Earth on planets is already something that can be done.

The question of how much fleet capacity should 1 system be able to support depends entirely on game philosophy. If the empire should always have enough supply, then it can be quite high. If you want supply to be factor in long wars, then it needs to be low. Even if you go with the first though, you should probably try to keep supply generation under 100 for a fully developed world. If a player gets two (or more) habitable planets in the same system, then builds a lot of habitats, then the local supply generation could be insane, allowing a very significant fleet to be based there. Getting that supply to the rest of the empire requires it be shifted starbase to starbase. Late game, you will primarily use gateways as now every supply generating world can be connected to the Bastion, Shipyard, or Anchorage where all your ships are stationed.

Transports would probably use 1 supply per day, and have a base storage for, say, 200 days?

 

[MichaelJanuary]

@Tamwin5 finally had some time to do some spreadsheet modeling.

Was trying to achieve one of your objectives of being able to build a large stockpile over a period of peacetime years, that gets burnt down over a few years of warfare ops.

This required that I keep supply generation choked off to a level where youd be forced to dock most of your fleets during peace to go into net positive supply generation, while wartime ops would place you in a net negative position.

The biggest change was in storage capacity. Had to massively buff the ability to store supplies at upgraded bases with anchorages, while at the same time limiting g the ability of starbases to generate supplies.

The results of my modeling got to a point where at most phases of the game you would take 20 years to saturate your network with supplies, and burn through in 8 to 10 yrs of warfare. The figures vary slightly depending if you over invest in battleships or push your naval capacity too hard, but that's fine. It becomes the player choice for how hard to push NC, and how to bias fleet building to efficient corvettes and destroyers or less efficient cruisers and battleships.

The main figures look something like this.

Supply generation:
Outpost = 0, +5 per upgrade.
Shipyard module = +5 each
Soldier jobs = +1 each
Civ jobs = +0.25 each

Supply Storage:
Outpost = 4000, and doubles for each upgrade
Anchorage = +5000 each

Transfer rates:
Outpost = 10, +10 for each upgrade.

In this model ... 1 naked Citadel has 64000 storage, generates 20 supply per day, can transfer 60 supply per day. By adding shipyards, anchorages, logistics offices, hyperlane registrar, and researching say 4 tiers of techs (40% bonus) this can be buffed to achieve up to 120k storage, or 60 supply generation, and/or close to 100 transfer per day.

That is sufficient for 1 citadel in an undeveloped system to fully resupply 30 BB or 1200 corvettes. The citadel would recharge 120k supplies over a period of 2 years (+60gen+100imp supply per day). Faster if it has multiple hyperlanes. Faster alsonif it has a well developed colony or two in the system.

The maths guide is that :
+X supply is roughly equivalent to X naval capacity.
So +1000 global supply gen can sustain 1000 corvettes moving, or 2000 corvettes docked at crew quarters.
With battleships having 8x the naval capacity and close to 2x the supply cost of corvettes, + 1000 supply can sustain 65 battleships moving, or 130 docked at crew quarters.

Supply transfer is close to double the rate of supply generation, so you would slowly drain your empire of supplies while conducting war ops. The higher the transfer rates, the more force you can concentrate in small regions. Transfer rates is less critical than generation or storage. If you dont want to deal with local shortages, then higher transfer rates will sort that out. However, having supply bottlenecks creates a mini game of optimising your network for distribution.

Any extended period of peace that has most of your fleets docked with crew quarters would fully saturate your network with supplies over a period of 10 to 20 years assuming you have not over invested in ships or underinvested in starbase upgrades and soldier jobs or pop growth.

 

[Tamwin5]

@Tamwin5 finally had some time to do some spreadsheet modeling.

Was trying to achieve one of your objectives of being able to build a large stockpile over a period of peacetime years, that gets burnt down over a few years of warfare ops.

This required that I keep supply generation choked off to a level where youd be forced to dock most of your fleets during peace to go into net positive supply generation, while wartime ops would place you in a net negative position.

The biggest change was in storage capacity. Had to massively buff the ability to store supplies at upgraded bases with anchorages, while at the same time limiting g the ability of starbases to generate supplies.

The results of my modeling got to a point where at most phases of the game you would take 20 years to saturate your network with supplies, and burn through in 8 to 10 yrs of warfare. The figures vary slightly depending if you over invest in battleships or push your naval capacity too hard, but that's fine. It becomes the player choice for how hard to push NC, and how to bias fleet building to efficient corvettes and destroyers or less efficient cruisers and battleships.

The main figures look something like this.

Supply generation:
Outpost = 0, +5 per upgrade.
Shipyard module = +5 each
Soldier jobs = +1 each
Civ jobs = +0.25 each

Supply Storage:
Outpost = 4000, and doubles for each upgrade
Anchorage = +5000 each

Transfer rates:
Outpost = 10, +10 for each upgrade.

In this model ... 1 naked Citadel has 64000 storage, generates 20 supply per day, can transfer 60 supply per day. By adding shipyards, anchorages, logistics offices, hyperlane registrar, and researching say 4 tiers of techs (40% bonus) this can be buffed to achieve up to 120k storage, or 60 supply generation, and/or close to 100 transfer per day.

That is sufficient for 1 citadel in an undeveloped system to fully resupply 30 BB or 1200 corvettes. The citadel would recharge 120k supplies over a period of 2 years (+60gen+100imp supply per day). Faster if it has multiple hyperlanes. Faster alsonif it has a well developed colony or two in the system.

The maths guide is that :
+X supply is roughly equivalent to X naval capacity.
So +1000 global supply gen can sustain 1000 corvettes moving, or 2000 corvettes docked at crew quarters.
With battleships having 8x the naval capacity and close to 2x the supply cost of corvettes, + 1000 supply can sustain 65 battleships moving, or 130 docked at crew quarters.

Supply transfer is close to double the rate of supply generation, so you would slowly drain your empire of supplies while conducting war ops. The higher the transfer rates, the more force you can concentrate in small regions. Transfer rates is less critical than generation or storage. If you dont want to deal with local shortages, then higher transfer rates will sort that out. However, having supply bottlenecks creates a mini game of optimising your network for distribution.

Any extended period of peace that has most of your fleets docked with crew quarters would fully saturate your network with supplies over a period of 10 to 20 years assuming you have not over invested in ships or underinvested in starbase upgrades and soldier jobs or pop growth.

I'd like to suggest a couple of changes to the model, see how it plays out.

1. Give outposts 1 supply generation. This would allow a fleet of a couple raider corvettes to capture some outposts and be self-reliant. I want ambushes and backstabs to be viable tactics. Keep the first starbase at 5 supply though, and the progression afterward.
2. Instead of 4k storage for outposts, doubling each level, give 2k storage to outposts, 10k for a Starport and +10k each level after. Have Anchorages give 10k each. It would make storage more reliant on the number of starbases you have (relatively equal across empires) instead of the number of outposts (can be vastly different, and RNG heavy). While it would decrease the supply storage of higher tier starbases (30k vs 32k, 40k vs 64k), it would increase the supply storage of anchorage star bases (30k vs 18k, 60k vs 36k, 90k vs 62k, and 100k vs 94k). This would mean that if you are trying to snipe enemy supplies, you would want to go for the anchorage starbases, not random outposts or the closest citadel. It would also have an elegant parallel when combined with the first suggestion: The four actual outposts go up by 5 supply generation and 10k supply storage, with an outpost being 1/5 of the Starport for both.
3. I'd double base transfer rates. You should be able to support a fleet through supply lines, in early game. It's only when you go above 20 corvettes that you sort running into supply bottlenecks. If you want to go for an early rush, you need to either get lucky on the tech roll, or pick your target carefully and strategically conquer to sustain your fleets.

I've also been thinking about the way ships docking to lower supply works. Currently, a fleet that is positioned defensively at a bastion during war takes the same supply as a fleet at rest during peace. I think a way to fix this would be to to make docking and fleet quarters be 20% supply reduction, and then a 20% supply reduction for being at peace in friendly space. That way it would be faster to recover supply during peace (with only 40% supply usage if properly docked), while reducing the strength of defensive docked fleets, as well as nerfing how much supply you would get by docking ships up mid-war to generate supply.

Another interesting thing is that losing ships loses the supply they had on board. Taking heavy loses, even if you have the alloys to rebuild, will cut into your supply bank.

You say that local transfer amount is less critical then total supply storage and supply generation. Supply transfer is key for winning battles. Supply generation is key for a large fleet. Supply storage is key for a long war. If you are defending a single chokepoint against a hostile neighbor, then all you care about is local supply. As long as you always win battles there, it doesn't matter if you have a third of the fleet they do. If you have a massive empire with many borders, then supply generation is more important, as you need ships to guard every border, and aren't trying to centralize supply. Supply storage would be useful for starving out enemies during a long war, such as against a federation or during the War in Heaven.

A mechanic I like about supply being a factor in wars, is that when you start running low on supply, you are basically forced to play defensively, keeping your ships at starbases. If both sides run out of supply, you end up with a situation where neither side can really mount an offensive, and it feels like EXACTLY the sort of situation that would result in a status quo peace.

Overall though, what did you think about the way things turned out? You gave some very good examples and insight, but not what your opinion on things was. Another thing that would be good to try out is opening up a save, looking at things, and figuring out what supply would be like in that situation.