Ashes is an IC2 byproduct left in the IC2 Generator after burning solid fuels like wood, coal, or planks on Minecraft 1.7.10.
Guide
Build a standard IC2 Generator using a Machine Block, a Battery, and a Furnace at a crafting table.
Place the IC2 Generator and load wood, coal, charcoal, or planks into its fuel slot to start producing EU.
Let the Generator burn solid fuel; Ashes will gradually appear as a leftover byproduct of combustion.
Take Ashes out of the Generator's output slot or pull it via a hopper from below into a chest.
Store Ashes in a chest and use it as a filler ingredient in IC2 fertilizer recipes combined with plant matter.
Ashes itself is not a fuel — do not feed Ashes back into the Generator, it will not burn again.
Ashes is used as a filler ingredient in IC2 agriculture recipes, most notably in IC2 fertilizer combined with plant matter like plantball or Bio Chaff.
Ashes is produced as a byproduct when an IC2 Generator burns solid fuels such as wood, coal, charcoal, or planks.
No. Ashes is not a fuel and cannot be re-burned in the IC2 Generator; it only accumulates as a residue.
No. Ashes is never naturally generated and cannot be mined; the only source of Ashes is operating an IC2 Generator.
Yes. Ashes behaves as a normal stackable item and can be pulled out of the IC2 Generator output with vanilla hoppers or mod pipes.