The Adjacency Bonus is a game mechanic in Supreme Commander which gives discounts and production bonuses to structures positioned next to each other. The nature of the bonus depends on both of the structures and can be very useful. Mass or energy can saved or produced, leading to a total of 4 possible bonuses.
¶ General
To have an adjacency bonus, there must be two structures placed next to each other; one giving the bonus and one receiving it.
- Any structure which produces a resource is a bonus giver.
- Any structure consuming a resource is a bonus receiver, including other bonus givers (upgrading mass extractors)
- Additionally, Storage are bonus giver to resource-producing buildings.
- Doubling the number of adjacent bonus givers next to a structure doubles the adjacency bonus on that structure.
The Bonus amount is dependent on the number of bonus givers which can fit around a bonus receiver. (minimum:4 maximum:16) This means that the larger a bonus receiver the more bonus givers must be next to it to give the same bonus.
Examples:
- A factory surrounded by 16 T1 power generators receives the same discount as a radar surrounded by 4 T1 power generators.
- A mass extractor surrounded by 4 storages receives the same percentage production bonus as a T3 mass fabricator surrounded by 12 mass storages.
¶ Consumption Bonus
A structure which produces a resource gives a discount to all structures next to it which consume that resource. It should be noted that only structures receive this bonus, not any engineers or engineering stations assisting them.
¶ 
Mass
The values in this table are given for one mass-producing structure next to a 4x4 building; more mass-producing structures would increase the discount. The typical discount value is to give you an idea of what you would most commonly see in the game, and should not be used for calculations. Buildings which give mass discount bonuses
| Mass Producing Structures | Discount for one structure | Production Bonus for all storages | Comments |
|---|---|---|---|
 T1 Mass Extractor |
7.5% | 0.3-1 |
Useful next to T1 Land Factories, if you're not going to eco much. |
 T2 Mass Extractor |
10% | 1-2 |
Useful next to T2 Land Factories. |
 T3 Mass Extractor |
12.5% | 2-4 |
Useful next to T3 Land Factories, Note: Quantum gateways only receive 10%. |
 T2 Mass Fabricator |
1.25% | 0.1-0.3 |
Not Very Useful. Note: If Both T2 and T3 Fabricators are turned off bonus doesn't apply. |
 T3 Mass Fabricator |
20% | 2-4 |
Useful next to T3 factories and high mass consuming structures (20/s or more). Note: Quantum gateways receive only 3.75%. Nukes receive only 12.5%. |
¶ 
Energy
The percentage discount value depends on how much of the structure in question is surrounded by power generators - as structures can be of different sizes, different numbers of pgens fit around them. This means that a factory that is 50% surrounded by 8 T1 pgens will receive the same bonus as, a radar surrounded by 2 T1 pgens - 12.5% for both. In this table, the discount percentages are shown for a fully surrounded structure.
| Energy Producing Structures | Discount Percentage | Typical Discount value | Comments |
|---|---|---|---|
 T1 Power Generator |
25% | 0.3-1 |
Useful next to radar, and air factories, not great next to land factories, but should still be used. |
 T1 Hydrocarbon PowerPlant |
12.5% | 1-2 |
% value for ONE Hydro shown. Useful next to T1/2 air Factories, generally useful. |
 T2 Power Generator |
50% | 2-4 |
Useful next to T2 air Factories. |
 T3 Power Generator |
75% | 0.1-0.3 |
Very Useful next to T3 air Factories. |
 T4 Paragon |
0% | 2-4 |
Useless - better to shield it. |
Buildings which give Energy discount bonuses
It should be noted that mass extractors consume energy to generate mass, but T1 pgens should only be used for adjacency when the extractor is upgrading from T1 to T2 very early in the game, to save some energy while upgrading.
¶ Production Bonus
Any structure which produces a resource, when placed next to a storage of that resource, will produce a bonus percentage of that resource. This is most commonly seen when mass extractors are surrounded by storage to increase their mass income.
- Bonus is 12,5% per fully surrounded side by storages.
- Maximum is 50% bonus income for a fully surrounded building by
storage.
- Maximum is 50% bonus income for a fully surrounded building by
¶ Mass
| Mass Producing Structures |
Production Bonus for one storage | Production Bonus for all storages | Comments |
|---|---|---|---|
| T1 Mass Extractor |
+0.25 | +1 |
Not very useful. Also not obvious due to how the game rounds the displayed values, same for T2 fabricators |
| T2 Mass Extractor |
+0.75 |
+3 |
Useful |
| T3 Mass Extractor |
+2.25 |
+9 |
Very Useful |
| T2 Mass Fabricator |
+0.125 | +0.5 |
Not Very Useful, unless the storages are next to an extractor |
| T3 Mass Fabricator |
+0.48 |
+5.76 |
Not Very Useful, better to place near t3 Pgens, Same for T2 Mass Fabs |
Buildings which are affected by mass storage
¶ Energy
| Energy Producing Structures |
Production Bonus for one storage | Production Bonus for all storages | Comments |
|---|---|---|---|
| T1 Power Generator |
+2.5 |
+10 |
Almost useless due to the explosion when the storage dies. |
| T1 Hydrocarbon Power Plant |
+4 |
+50 |
Almost useless due to the explosion when the storage dies. |
| T2 Power Generator |
+27.78 |
+250 |
Almost useless due to the explosion when the storage dies. |
| T3 Power Generator |
+78.125 |
+1250 |
Almost useless due to the explosion when the storage dies. |
Buildings which are affected by Energy storage
Note: Adjacency Bonus should be used well-considered. Players with little experience tend to surround hydrocarbon power plants with energy storage to get 50% more energy or similar things. The bonus you want to have can quickly turn into an economic disadvantage if you try to profit that way. Keep in mind the costs of 12 energy storages which amount to 14400 energy and 3000 mass. The mass covers the costs of a T3 power generator which would produce 2500 energy instead of additional 1250.
¶ Weapon Bonuses
Placing Power Generators next to energy-consuming weapons will reduce the reload time of the weapon, the duration of energy consumption as a result, and the energy consumption itself. All static artilleries benefit from the rate of fire bonus and energy drain reduction. UEF T3 Point Defense is an exception and only gains a reduction in energy drain.
The values in the following tables are given when a unit is surrounded by a specific power generator.
¶ Rate Of Fire Bonus
When placed next to power generators, static artillery units gain a rate of fire bonus which can be very significant, especially when considering that a 60% reload time can be achieved, and how much cheaper 4 T3 power generators are than a T3 artillery installation. The reduction of a reload time can be calculated with the following scheme if a unit is fully surrounded by the same type of power generator:
- 10% discount for T1 power generators.
- 20% discount for T2 power generators/hydrocarbon power plants.
- 40% discount for T3 Power generators.
The Aeon T4 Rapid-fire Artillery can achieve the maximum possible reload time discount of 20%. You can place a T1 power generator on each side in addition to a T3 power generator. For Salvation each T2 power generator gives 2.5% reload discount and each T3 gen gives 4.5% reload discount.
This table shows all possible time values:
| Artillery Unit |
T1 Power Generator | Hydrocarbon Power Plant | T2 Power Generator | T3 Power Generator |
Comments |
|---|---|---|---|---|---|
 T2 Artillery |
2s | 5s | 5s | 8s | T1 pgens useful, especially with multiple artillery structures. |
 T3 Artillery |
1s | 2.5s | 2.5s | 4s | Very useful with T3 pgens, or any pgens. Note: Aeon artillery has twice the reload time and so twice the discount. |
 T4 Rapid-fire Artillery |
0.3s | 0.4s | 0.4s | 0.5s | The size allows you to surround it with a T3 and T1 pgen. Reload time discount: 0.6s. |
 T4 Artillery |
2s | 5s | 5s | 8s | Very useful with T3 pgens, or any pgens. |
 T3 Ravager |
0s | 0s | 0s | 0s | Only profits from energy consumption reduction (see table below). Quite useless. |
Reload Time discount on Artillery structures
¶ Energy Consumption Reduction
The rate of fire bonus reduces the time structures consume energy, but will also increase the frequency of energy consumption as a result of the increased fire rate. But in addition to that, power generators give a general discount on energy consumption to static artilleries. Making decisions around this behaviour is not recommended as the energy reduction is very low compared to the resources invested. This table is mostly to provide you with information on how it works.
| Energy Producing Structures |
Discount Percentage | Typical Discount value | Comments |
|---|---|---|---|
| T1 Power Generator |
10% | 10-750 |
Useful next to all static artillery, especially T2, when safety is important |
| T1 Hydrocarbon Power Plant |
20% | 30-1500 |
Useful next to T2/T3 static artillery |
| T2 Power Generator |
20% | 30-1500 |
Useful next to T2/T3 static artillery |
| T3 Power Generator |
30% | 60-3000 |
Useful next to T3/T4 static artillery |