Hydroelectric Generator

The Hydroelectric Generator is a compact power source that became much easier to handle once the Water Pump was added. It generates electricity from falling water, and its layout is straightforward enough that a single unit can be built into a very small vertical setup. With a height of 5 blocks total — 3 blocks above the generator for the Hydroelectric Generator and Transmission Wire, 1 block for the Water Pump base, and 1 block of space for the water to fall through — it can function as long as the structure is arranged correctly.

Each generator occupies 4 horizontal tiles, so you can decide how many to place side by side based on your power needs. Despite its small footprint, a setup like this produces about 950–1000 Wh per day, which is roughly equal to five Wind Turbines. That makes it strong enough to run facilities such as the Advanced Laboratory and the Circuit Factory on its own.

A useful feature of the Hydroelectric Generator is that it does not stop working just because it is submerged in water, which makes it possible to save space by pumping from the base section. The amount of water matters, though: each generator needs roughly 20–40 units of water. Too little or too much water reduces performance. A good target is to keep the water level a little above half a block, and in practice it works best when the falling-water tile has just enough water to keep the generator active without crossing the shutdown threshold.

A Deweb produces 5 water per day, so one source can cover about 4–5 days’ worth of use. Even so, it is best to watch the generator’s behavior and adjust the water amount as needed, since the ideal level depends on the exact build. If you add too much water, the generator stops when the falling tile contains more than 1 tile of water, and the Water Pump itself also stops if the overall water height exceeds 1 tile. For that reason, it is better to fill the system conservatively at first, then remove excess water manually if necessary.

Construction can be awkward because of the shape of the setup. If you let A_Ratizen build the Water Pump directly, they are very likely to get trapped, so it is safer to use a drone, do it yourself, or supervise the work closely. One practical method is to build two floors at height 2 first, then place the Deweb on the upper level. Since adding water later is somewhat troublesome, starting with slightly more than enough and then reducing it by hand is often the easiest approach.

If you want to save even more space, you can replace the Transmission Wire with a transmission block and reduce the vertical space by 1 block. However, this is usually not recommended, because Iron Plate production takes considerable labor and can significantly lengthen the construction time.