|This article is about an older version of DF.|
Power is used to drive devices that perform tasks normally done by dwarves, such as pumping water using a screw pump or milling certain types of food into flour at a millstone. Power is produced by windmills and water wheels.
 Power requirements
- Axle: (1) per tile (horizontal axles and verticle axles both)
- Gear assembly: (5)
- Millstone: (10)
- Pump: (10)
 Power transfer
Power can be transferred between devices using gear assemblies and axles. Axles transfer power in a single direction -- north, south, east, west, up, or down. Axles are classified as "horizontal" or "vertical", with the former going north/south or east/west, and with the latter going up or down Z levels. Horizontal axles may be built individually up to 10 tiles long; if you want a longer axle, you may simply build two or more of them in a line; you don't need gear assemblies between them. Vertical axles are always placed one tile at a time.
Gear assemblies take up a single tile and transfer power to any device within the six orthogonally adjacent tiles (north, south, east, west, above, below). Gear assemblies are best used for moving power through right-angles. For example, they can be built as bases for windmills to move power out sideways along an axle.
Because of the high power use of gear assemblies (5), axles are more appropriate and convenient to build when transferring power across horizontal or vertical distances. An axle uses (1) power for every tile of power transfer. An axle 5 tiles long will use (5) power. Axles can be directly attached to windmills, waterwheels and screw pumps in order to provide power. For security, one can make a axle-train cross a moat by first going down the moat, across, and then up. Or perhaps a screw pump will make a floor-type security-wall for a downward axle.
Devices that use power are also capable of transferring it. Adjacent screw pumps will transfer power between themselves. The only way to prevent this is to leave a tile gap between devices, or move them diagonally from each other.
 Frozen Components
Machine components on ice will freeze solid. This also causes all connected components to stop working. When you look at a component using 'q' you see if the component is 'frozen'(not working because it is frozen solid) or if it's "frozen elsewhere"(not working because another component is frozen solid)