It would take a very cooperative, straight section of river, and at least 8 watermills, 4 on each side, all side by side, to start to rival the 2,200W output of just 2 well-spaced watermills (and in just over the space required by 2).There is probably never a good time for the 'Zzztt' event in RimWorld. However, 3 overlapping watermills only give 90% the power of a single mill, and 4 would only give 120% power of a single one. Therefore, given a sufficiently straight river, the maximum power output is achieved by cramming as many watermill generators along both sides of a river as possible. The -70% exclusion zone reduction does not stack. Double thick walls will help prevent casual grenade throws from breachers from opening up the generator to attack, as two such random attacks will be necessary to allow the raiders to target the generator. Therefore, even wooden walls, constructed over bridges, are sufficient to protect a watermill generator for the majority of cases. As watermills are created over water, it is unlikely for them to willingly pass through. Sappers and breachers will only break walls if it would be in their way. Most raiders will not target anything enclosed in walls & doors if they have another target (colonist, targetable animal, or building) that is accessible without breaking a wall. In practice, watermills can be defended by surrounding them in walls. And, because efficient watermills need to be spread out, they are slightly harder to defend than other power systems. Their main problem is map limitation, requiring a river or creek to build off of. Therefore, watermills are a great source of power. Watermill generators offer 100% consistent power, without requiring fuel, while also being cheaper to obtain and research than geothermal generators. Raiders will rarely, if ever, target this. The exclusion zone, explained above (blue on previously built watermills, green if OK, flashing orange if overlapping)ĭespite being surrounded by wood walls, this watermill gives 100% power and is reasonably safe.The 1x5 waterwheel of the generator off one side of that (green if placeable, red if not).The 5x5 housing of the generator (green if placeable, red if not).The 3x3 base of the generator (in white).When placing the watermill generator, the blueprint will show: Water inside this zone has no effect - bridges, walls, and land inside an exclusion zone do not interfere with power generation. The output of watermills will be reduced to 30% (330W) if you overlap their exclusion zones.

They are 13x7 rectangles, extending 4 squares above, below and outside the mill.

with neither its housing nor wheel overlapping any other buildings or walls.

with its water wheel entirely in moving water.on solid ground, not on a bridge or marsh) with its 3x3 base on tiles that can support Heavy (i.e.Only the 3x3 base must be on firm ground. Then, a 1x5 waterwheel is attached to one side of the housing, making the total footprint 5圆. The base is a 3x3 square in the middle of the housing (in white) the housing extends another 1 square beyond that, making a 5x5 square. This includes rivers and creeks, but not ocean. solid ground, not mud or gravel) and moving water. The watermill generator is unique in that it requires two different types of terrain: heavy terrain (i.e. Watermill generators produce a constant 1100 W of power after being constructed. They require 280 Wood, 80 Steel, 3 Components, 4,000 ticks ( 1.11 mins) of work, and a Construction skill of 6. Watermill generators can be constructed once the Watermill generator research project has been completed.

Rimworld wind turbine vs solar pannel