2013-12-17 12.05.30

A Fermenter

Fermenters are a critical part of ethanol crystal production. Using water and a small amount of power, they can turn sugar and dirt into yeast, and then yeast and plant matter into sludge, which can then be smelted to produce ethanol.

Rotarycraft Handbook DescriptionEdit

"The fermenter is how you produce the ethanol for the engines that require it. To make yeast, place sugar in the top slot, and dirt on the bottom.  To make sludge, put yeast on top and plant matter on the bottom.  Put that in a furnace, and you will get crystals of ethanol.  This machine's operational speed rises as the input speed does.  This machine is temperature-sensitive, and very low or high temperatures will slow it down or even kill the yeast.  To automate this machine, use redstone to choose the target production item (displayed at the top-right of the GUI).  The middle GUI slot is in fact a water gauge, not an item slot."


The fermenter requires a water and power supply for its processing. To produce yeast, sugar is placed in the top and dirt in the bottom slot. 

Similarly, to produce sludge, yeast is put in the top and any kind of plant matter (saplings, flowers, sugarcane, leaves, etc.) in the bottom slot. The sludge can then be smelted in to produce ethanol crystals. Leaves yield 2 sludge per leaf block, while other plant items yield one sludge per item. If Thaumcraft is installed, Greatwood leaves yield 8 sludge per leaf, and Silverwood leaves yield 64 sludge per leaf.

For efficient processing it is required to keep the fermenter in the green area of the temperature gauge. this can be achieved by heating or cooling. At optimal temperature, each operation will take about a second. If the temperature is too high or too low, operations will be much slower, or will not happen.

You can use a DC electric engine to power the fermenter.

Power SpecificationsEdit

Required Power

1024 W

Required Speed

32 rad/s

Power Input


Duration of Operation FormulaEdit

Time = 480 - 35 × log₂ (speed + 1) (As of Minecraft 1.7.10, Rotarycraft version 19a)

Note: The Fermenter also has an "ideal" temperature it works at. Outside of this temperature, a small multiplier is applied that slows down the operation, which grows exponentially.

Tips/Tricks: Edit

At the optimal temperature, a fermenter will operate in 1 tick given an input speed of 16 krads/sec. This can be provided by a Steam Engine and a 32x gear ratio set for speed. This is slightly more speed than needed (13,176 rads/sec will give you this operation time) but due to Rotarycraft power of two style of operations, this is the closest you will get.