Energy Units

Energy Units (EU) are a type of energy API in modded Minecraft. It was introduced in IndustrialCraft 2 and is consumed primarily by its machines and related addons. EU acts as a form of electricity, similar to real electricity in some ways. It is not interchangeable with GregTech Community Edition's Energy Units.

Production
EU is produced through Generators. IndustrialCraft adds many different generators, but the (standard) Generator, Solar Panel, and Geothermal Generator are the most basic ones. The most powerful generator in IndustrialCraft 2 is the Nuclear Reactor, capable of outputting thousands of EU per tick, but requires careful design and automation to do so.

Addons and other mods, such as GregTech, add more powerful generators.

Transport and Storage
EU is transported via wires and cables. The most basic cable is the Tin Cable. Wires can be insulated with Rubber to form Insulated Cables, which lose less energy. Uninsulated cables will, as well as transfer energy less efficiently than Insulated Cables, deal shock damage to any entities that are too near or touch them (and can be used to set up traps and mob farms). All cables are rated to carry a certain amount of EU per tick. In older versions, if their limit is exceeded, they will melt; however, for developmental reasons, the transfer limits on cables are currently disabled.

All IC2 Generators and machines store a small amount of EU internally. However, most EU is stored in dedicated EU storage blocks such as the BatBox, MFSU, or another device added by an addon (such as the AFSU). MFEs also accept EU. Copper Cables can be used to channel energy if needed. Several Generators are suggested to charge MFSUs, and using Geothermal Generators are the most efficient, especially if the player is using Lava Cells, as they generate the most EU/t at 20 EU/t.

EU can also be transported and stored in items. IndustrialCraft 2 adds several electric tools and suits of electric armor that consume EU instead of durability, such as the Electric Jetpack and the Mining Drill. Additionally, the RE-Battery, Advanced RE-Battery, Energy Crystal, and Lapotron Crystal are a set of items used primarily as crafting components and also as portable rechargeable energy cells. However, the Lapotron Crystal is not accepted by all energy cells, such as the MFE.

Redstone dust can also be used to power machines, allowing for ad hoc powering of machines even before setting up a Generator.

Pre-IC2 Experimental
In July 2013, as IndustrialCraft 2 was being updated to Minecraft 1.6.2, much of the mod underwent a substantial rewrite, resulting in the creation of the IC2-Experimental branch. One system that was rewritten was the EU system. While the rest of this article details EU in its current state, this section will discuss its earlier (Minecraft 1.5.2 and earlier) aspects.

GregTech 5
GregTech 5 uses its own system of EU, designed to more closely match the pre-Experimental EU system.

GregTech cables and Battery Buffers can output EU normally to all EU-accepting blocks, but will not accept EU from non-GregTech sources. This can be overcome with a Transformer which will accept EU from non-GregTech sources and emit GregTech EU.

Usage
EU is consumed to operate machines. Many mods use EU, including but not limited to:
 * IndustrialCraft 2 and.
 * MineFactory Reloaded.
 * Modular Powersuits.
 * Applied Energistics/Applied Energistics 2.
 * All mods that implement Universal Electricity, including MineChem, GalactiCraft, and Modular Force Field System.
 * RotaryCraft (via the Electric Motor).
 * Forestry (via the Electrical Engine).