Nine coal power plant configuration. With Mk3 belts and Mk2 miner a pure coal node (or two normals) and power shard to get the extra 30 coal per min.

Mid Section of a two blue print vanilla early (mk 3 belts 270 ppm) design. Outer BP: https://satisfactory-calculator.com/en/blueprints/index/details/id/3576/name/Coal+Power+Outer

Coal: Each coal plant at 100% needs 15 ppm. This means you can run 18 power plants at mk3 on one main feeder line split into two groups of 9. 15ppm18PowerPlants=270 Water: Each coal power plant needs 45 Water ppm.
Each water extractor produces 120 ppm at 100%. 9 CoalPowerPlants45 WaterPerMinute = 405 WaterPerMinute needed per group of nine This comes out to 3.375 Water Extractors per 9 Coal power plants. You can powershard the extra 15ppm water or can use 4 water extractor per 9. Note pipes teir one can only have 300 water per minute so you cant feed all 9 with one feeder until teir 2 pipes.

MK3 Input: 270ppm Coal 45ppm Water per

MK3 Output: 1350 MW of power

This setup scales up easily to the next teirs of belts. This is based up on belt speed https://satisfactory.fandom.com/wiki/Conveyor_Belt AND available coal input. https://satisfactory.fandom.com/wiki/Coal?so=search#100%_Clock_Speed This is easily
At mk 4 belts (480 ppm) you can feed 27 coal power (15x27=405 coal per min required) plants easily with one main normal spliter feeding 3 lines. Output 2025 MW At mk 5 belts (780 ppm) you can feed 52 coal power (15x52=780 coal per min required) Mk3 Mine extractor on a pure node with one power shard set to 780 ppm. this will feed almost double m4 just remove two power plants, each from different feeder lines. Output 3900 MW Note: At pipes teir 2 you can feed the water lines for 9 off the middle bp