Energy Unit

The Energy Unit, often abbreviated as EU, is the unit of energy used by IndustrialCraft² and its add-ons(and Immersive Engineering before MC 1.8). It is similar to the SI unit of the Joule. EU can be created through various generators, stored in certain blocks and items (e. g. the BatBox, RE-Battery or BatPack), and transported through cables to power machines.

Two common terms are used to describe EU, EU/t (EU per tick) and EU/p (EU per packet). These two terms represent different concepts (Power and Energy respectively) and are technically not interchangeable.

EU/t

EU/t means Energy Units per Tick, and is a unit of power. It is a derived unit that represents the energy transferred over time and is similar to the Watt. EU/t can be measured by an EU-Reader, giving the average EU/t flowing through a cable or block. EU will not flow if there is nothing to actively draw it.

EU Packets

An EU Packet represents a discrete collection of energy, and can be thought of as a voltage. All machines and cables accept a maximum packet size and almost all generators and storage units only output energy in specific packet sizes. EU Packets can have various sizes, ranging from 1 to 8192 EU, or even up to 2 billion EU with some GregTech 4 machines. This packet size is given in EU per Packet, or EU/p for short. The sum of all packet sizes traveling through a cable equals the total EU/t.

EU Packets behave as a single entity when traveling through cables and when output or accepted by machines. Consequently, distance related losses that occur when EU travels through cables are applied to each entire packet. Therefore, smaller packet sizes will lose more energy when traveling through a cable, for the same total amount of energy.

Voltage

Different ranges of packet sizes are grouped as different voltage levels. Although the voltages themselves have always remained the same, the machines which can generate or accept them have changed significantly from Minecraft 1.5 to Minecraft 1.6 with the introduction of IndustrialCraft² Experimental.

Note that certain items listed in the table are only available with certain add-ons installed, such as GregTech 4, CompactSolars or Advanced Solar Panels.

Before 1.6

Name	Max. Size	Emitted By	Cable
Micro Voltage (µV) or Ultra Low Voltage (ULV)	8 EU	Solar Panel, Water Mill, Wind Mill	Tin Cable, Copper Cable, Gold Cable, Glass Fibre Cable, HV Cable, Superconductor Wire
Low Voltage (LV)	32 EU	Advanced Solar Panel, BatBox, Generator, Geothermal Generator, LV Solar Array, LV-Transformer, Nuclear Reactor	Copper Cable, Gold Cable, Glass Fibre Cable, HV Cable, Superconductor Wire
Medium Voltage (MV)	128 EU	Hybrid Solar Panel, LV-Transformer, MFE, MV Solar Array, MV-Transformer, Nuclear Reactor	Gold Cable, Glass Fibre Cable, HV Cable, Superconductor Wire
High Voltage (HV)	512 EU	HV Solar Array, HV-Transformer, MFSU, MV-Transformer, Nuclear Reactor, Ultimate Hybrid Solar Panel	Glass Fibre Cable, HV Cable, Superconductor Wire
Extreme Voltage (EV)	2048 EU	Adjustable Energy Storage Unit, Nuclear Reactor, HV-Transformer, Plasma Generator	HV Cable, Superconductor Wire
Quad Extreme Voltage	8192 EU	Nuclear Reactor, Lightning Rod	Superconductor Wire
Ultimate Voltage (UV)	2 Billion EU	Fusion Reactor, Supercondensator	Superconductor Wire

Since 1.6

Name	Max. Size	Emitted By	Cable
Micro Voltage (µV) or Ultra Low Voltage (ULV)	8 EU	Solar Panel, Water Mill, Wind Mill	Tin Cable, Copper Cable, Gold Cable, Glass Fibre Cable, HV Cable, Superconductor Wire
Low Voltage (LV)	32 EU	Advanced Solar Panel, BatBox, Generator, Geothermal Generator, LV Solar Array, LV-Transformer, Nuclear Reactor, Radioisotope Thermoelectric Generator	Tin Cable, Copper Cable, Gold Cable, HV Cable, Glass Fibre Cable, Superconductor Wire
Medium Voltage (MV)	128 EU	Hybrid Solar Panel, LV-Transformer, CESU, MV Solar Array, MV-Transformer, Nuclear Reactor	Copper Cable, Gold Cable, HV Cable, Glass Fibre Cable, Superconductor Wire
High Voltage (HV)	512 EU	HV Solar Array, HV-Transformer, MFE, MV-Transformer, Nuclear Reactor, Ultimate Hybrid Solar Panel	Gold Cable, HV Cable, Glass Fibre Cable, Superconductor Wire
Extreme Voltage (EV)	2048 EU	Adjustable Energy Storage Unit, MFSU, Nuclear Reactor, HV-Transformer, Plasma Generator	HV Cable, Glass Fibre Cable, Superconductor Wire
Quad Extreme Voltage	8192 EU	Nuclear Reactor, EV-Transformer, Lightning Rod	Glass Fibre Cable, Superconductor Wire
Ultimate Voltage (UV)	2 Billion EU	Fusion Reactor, Supercondensator	Superconductor Wire

Transformation

Transformers can be used to change the size of EU packets. All transformers have one high and five low sides. By default, current entering the high side will be transformed down one voltage level, splitting the packets up if necessary, and outputting it through the five low sides. Applying a Redstone signal to a transformer inverts its function, making it transform packets from the low sides up one voltage level and outputting it from the high side. The latter mode is however practically never necessary, due to higher voltage cables and devices being able to transmit and work with lower voltage levels.

As of Minecraft 1.6 IC² Experimental, all transformers now have a GUI, which can be used to set a specific mode independent of any Redstone signal.

Note that all transformers can only output as much energy as can fit into its maximum packet size. For example, a down-transforming LV-Transformer can only output up to 128 EU in the form of four 32 EU packets, due to the maximum packet size being 128 EU, even if multiple 128 EU packets are supplied on the high side.

Name	Low Side Voltage	High Side Voltage
LV-Transformer	Low Voltage (32 EU/p)	Medium Voltage (128 EU/p)
MV-Transformer	Medium Voltage (128 EU/p)	High Voltage (512 EU/p)
HV-Transformer	High Voltage (512 EU/p)	Extreme Voltage (2048 EU/p)
EV-Transformer (since 1.6 only)	Extreme Voltage (2048 EU/p)	Quad-Extreme Voltage (8192 EU/p)