Factorio beacons: diminishing returns in 2.0
Each beacon passes on 1.5 times its modules' effect, divided by the square root of the number of beacons reaching the machine. Eight beacons give 2.83 times what a single beacon would on its own, not 8 times, so a few well-placed beacons do most of the work.
The formula
With n identical normal beacons around a machine, each beacon transmits 1.5 ÷ √n of its modules. Added together that is 1.5 × √n times the effect of the modules in one beacon.
| Beacons reaching the machine | Total, × one beacon's modules |
|---|---|
| 1 | 1.50 |
| 2 | 2.12 |
| 4 | 3.00 |
| 8 | 4.24 |
| 12 | 5.20 |
| 16 | 6.00 |
| 20 | 6.71 |
Example: a beacon with two speed module 3 (+50% speed each) holds +100% speed. One such beacon adds +150%; eight of them add +424%.
Beacon facts
- 2 module slots, speed and efficiency modules only (no productivity or quality modules).
- Affects machines that touch its 9 × 9 area.
- Uses 480 kW at normal quality, falling to 80 kW at legendary.
- Higher quality beacons transmit more: 1.7, 1.9, 2.1 and 2.5 at legendary, with no extra diminishing returns, so one legendary beacon is worth about 1.66 normal ones.
How many beacons a machine can touch
| Machine size | Most beacons | Total, × one beacon |
|---|---|---|
| 2 × 2 to 4 × 4 (assemblers, chemical plants) | 12 | 5.20 |
| 5 × 5 to 7 × 7 (foundries, oil refineries) | 16 | 6.00 |
| 8 × 8 to 10 × 10 | 20 | 6.71 |
Most real layouts use rows: a row of 3 × 3 machines between two lines of beacons usually gets 8 beacons each, a row of 5 × 5 machines 10. Going beyond that costs a lot of space and power for a small gain.
Beaconed builds: module factories and all blueprints.