The fermenter is how you produce the ethanol for the engines that require it. To make yeast, place sugar in the top slot, water in the middle, and dirt on the bottom. To make sludge, put yeast on top, plant matter (saplings)  on the bottom slot and water in the middle slot. 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). 

Required Power: 1024W

Required Speed: 32 rad/s

Power Input: Back