Energy Units

Energy Units, or EU, is one of the oldest forms of energy in modded Minecraft. It is added by IndustrialCraft 2 and consumed primarily by it and its add-ons. EU acts as a form of electricity, in some ways similar to real life electricity.

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 added. The most powerful generator in IndustrialCraft 2 is the Nuclear Reactor, capable of outputting thousands of EU per tick, but requiring careful design and automation to do so.

Addons and other mods, such as GregTech 4 and GregTech 5, add additional, more powerful generators.

Transport and Storage
EU is transported via wires and cables. The most basic cable is the Tin Cable. Cables are insulated with Rubber. Uninsulated cables will still transfer energy, but will deal shock damage to any entities that touch them (while this is hazardous, it can be used to build mob farms and traps). All cables are rated to carry a certain amount of EU per tick. If their limit is exceeded, they will explode. 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: the BatBox, CESU, MFE, and MFSU, or another device added by an addon (such as the AFSU).

EU can also be transported and stored in items. IC2 adds several electric tools and two suits of electric armor that consume EU instead of durability. This includes the famous Electric Jetpack. Additionally, the RE-Battery, Advanced RE-Battery, Energy Crystal, and Lapotron Crystal are a set of items used primarily as crafting components and as portable rechargeable energy storage objects.

Pre-IC2 Experimental
In July, 2013, as IndustrialCraft 2 was being updated to Minecraft 1.6, much of the mod began a substantial re-write, 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, and by extension GregTech 6, use their 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. However, a Transformer will accept EU from outside 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 and Applied Energistics 2
 * All mods that implement Universal Electricity, including MineChem, GalactiCraft, and Modular Force Field System
 * RotaryCraft (via the Electric Motor)