Module
Modules are items used to enhance existing buildings' capabilities. They are expensive, require appropriate research, and are produced slowly, but can eventually greatly improve the efficiency of a factory.
Quick usage summary:
- For more products per second a speed module should be used.
- For more products per input resource a productivity module should be used.
- For more products per watt of energy an efficiency module should be used.
Types of modules
There are three types of modules in factorio, each with 3 tiers of effect. Crafting higher tiers requires lower tiers to be made.
Speed Module
Increases the speed and energy consumption of a machine.
| Module | Speed bonus | Energy consumption |
|---|---|---|
 |
+20% | +50% |
| |
+30% | +60% |
| |
+50% | +70% |
Advantages & Disadvantages:
- Increases speed of machine.
- Increases energy use per cycle.
- Indirectly increases pollution generated due to energy consumption being higher.
Productivity Module
Productivity modules add a second purple "production bar" at item producing buildings and labs. It fills by the productivity bonus per craft. When it reaches 100%, an extra item (or items, in recipes that result in more than one) is produced.
Productivity modules can only be used to make intermediate products (except Uranium-related products). These are items that are used in other recipes and cannot directly be placed. Productivity modules cannot be placed in Beacons. Productivity modules can be used to boost the research inside labs per science pack.
| Module | Productivity bonus |
Energy consumption |
Speed | Pollution multiplier |
|---|---|---|---|---|
| |
+4% | +40% | -15% | +5% |
| |
+6% | +60% | -15% | +7.5% |
| |
+10% | +80% | -15% | +10% |
Advantages & Disadvantages:
- Creates an additional free item occasionally.
- Increases energy use per cycle.
- Increases pollution generated.
- Slows the machine.
Efficiency Module
The efficiency module reduces the cost of electricity to run the machine. The minimum energy usage is 20% of the base energy usage.
| Module | Energy consumption |
|---|---|
| |
-30% |
| |
-40% |
| |
-50% |
Advantages & Disadvantages:
- Reduces energy cost per cycle.
- Indirectly decreases pollution generated due to energy consumption being lower.
- No downsides
Usage tips
As a rule modules do not have diminishing returns (except that consumption is capped to -80%), that is if an assembler is making 2 items per second, adding 1 speed 3 module (+50% speed) will increase item production by 1/s, a second speed3 module will increase production by the same 1/s. Consumption modifiers work the same way, for example if a machine is consuming 180kW, the first efficiency 1 module will reduce energy use by 54kW, the second will also reduce energy use by 54kW. There is no difference between putting 2 speed 1 modules in one machine and 2 efficiency 1 modules in a second machine, than putting 1 of each in both machines - in both cases the total items produced per second and average energy required per item is identical.
There is however synergy between productivity modules and speed modules, productivity modules reduce crafting speed which lowers the production rate of items and increases the energy consumed per item, the speed bonus from speed modules increases production rate of items and lowers the energy consumed per item - in fact when dealing with productivity modules, the reduction in energy consumption from the increased speed from speed modules can be greater than the increased energy consumption. For detailed calcultions on the synergy between productivity modules and speed modules refer to this discussion.
Filling the device with speed modules is useful when a resource is infinite but the amount of resource pools is low. The best example would be oil deposits. Another good place to use speed modules would be for assembly machines which make products that take a long time to make, for example engine units. Using speed modules allows more compact of setups, because one machine can provide materials to more consumers than normal.
Filling devices with productivity modules is recommended when resources are scarce. An example would be more advanced products not being produced enough due to bottlenecks. It will take longer and more energy, but the overall amount of products per time will be higher. Productivity is especially useful in recipes that consume a lot of resources per second such as Electronic circuits, as this will result in a lot of free items being created and quickly cover the cost of the module. Also by saving the need to mine ore, smelt plates and process intermediates for those free items the additional energy cost can be easily covered.
Filling devices with efficiency modules is recommended for electric furnaces as these use a lot of power. Efficiency modules also completely lack downsides, so filling all unnecessary module slots with Efficiency modules if possible is recommended. Note that making higher level efficiency modules is not worth it in terms of power saved vs materials used to build a solar panel setup with same power output so the only incentive is to further reduce pollution or space utilization. Modules are also able to control Pollution, as pollution depends also on Energy usage. So reducing a machines energy usage by 40% with a efficiency module 2 will also reduce its pollution by 40%. Beware as this also works vice versa!
Examples of usage
Electric furnaces are huge power hogs at 180 kW per furnace. 1 basic efficiency module reduces it by 54 kW (-30%) - almost a Solar panel worth of power.
Electric mining drills create 9 units of Pollution with no efficiency modules and 1.8 with 3 basic ones.
Same Electric mining drill with 3 Productivity modules 3 would create 76.5 units of Pollution.