Applied Energistics is a modification to Minecraft that focuses on creating a compact, easily accessible, considerably expandable and extendible storage system called an ME Network. The "ME" in the title stands for "Matter<->Energy" - the premise being that items added to the system are converted into energy and stored in a digital energy form before needing to be used again, whereupon they are converted back into matter.
In addition to providing a potentially attractive solution to storage, the storage network can later be expanded to include the capability to craft recipes-on-demand by adding an ME Molecular Assembler Chamber. A comprehensive automation system may also be added, with the capability to interface with nearly any machine, no matter what mod it belongs to, with basically no limit to the amount of machines that can be added. In addition, this automation system can be used in conjunction with or in place of other automation mods like BuildCraft Pipes, Factorization Routers, Thaumcraft 3 Golems, and so on, depending on the user's preferences.
In a basic ME Network, one needs to supply and connect an ME Controller, an ME Drive (or ME Chest, not recommended as it's not expandable), at least one storage disk, bare minimum being ME 1k Storage, though a few ME 4k Storage disks are recommended, and finally an ME Access Terminal. Arrange them, touching, in a way that you find acceptable, and place the Storage Disk(s) in the ME Drive or ME Chest.
After attaching the machines, you'll notice that they're not doing much. Applied Energistics Machines require energy, and thankfully, in the version current with FTB Ultimate and DireWolf20 Modpacks, they can take it in the form of either EU or MJ. MJ is worth about 2.5 times more than EU. Each EU is worth 2 AE power units while each MJ is worth 5 AE power units. One can see the power needs by right clicking the ME Controller to access the GUI. Individual ME devices will not need independent power sources as long as they remain physically connected to the network. Power for the entire network can be supplied by attaching sufficient power to any Cubic Block in the network.
This storage system alone may satisfy you, giving you an indispensable solution to organizing the large amounts of items that you mine, punch, or otherwise find. Keeping an ME Network simply for storage eliminates the need for large storage rooms, saves you hours of time wasted on sorting items, and almost makes the everyday chest obsolete. Additionally, an ME Network can fulfil a couple more roles in your base.
The first, more basic addition, is ME Automation. Most of ME Automation is simply managed through the use of Import Buses and Export Buses that have been connected to the main ME Network, usually via an ME Cable. ME Automation allows you to place items directly inside machines for processing, and then to remove the finished product to return to your central inventory, or for further use - it's all as specified by you. The Bus interfaces are simple without being too constricting; if there's a problem, it's generally easy to see and fix. Overall the Import and Export Buses are very functional and are very compatible as far as their ability to interface with and automate machines external to the ME Network.
A second optional addition to the ME Network adds the possibility to simplify your MineCraft life even further by allowing for crafting run by the ME Network. One may add the capability for this auto-crafting onto the network by building a multiblock Molecular Assembler Chamber, connecting it to the ME Network with ME Cables, and then supplying this Container with ME Blank Patterns that have been encoded with recipes with an ME Pattern Encoder. These recipes can then be requested to be crafted directly from the ME Access Terminal. Once a craft is requested, if the required items are available in the system, it is automatically crafted. Even more interesting, if the required items do not exist, but the recipes for those items do exist in the system (assuming they come with with proper supplies and any further recipes needed), the system will craft what is necessary to craft the requested item for you. It is entirely possible to automate the creation of everything from Levers and Torches to a GraviChestPlate if done properly.
While access to the full capabilities of an ME Network with ME Crafting Access and ME Automation are often out of the reach of players until late-mid- or late- game, it is very possible to create at least a capable storage system relatively soon after establishing a reliable source of power as long as one avoids making storage disks larger than the 4k Storage as disks larger than this can completely drain one's resources and usually aren't worthwhile until late in game.
Applied Energistics also adds one ore to WorldGen - Quartz Ore, from which tools can be made. The quartz contained within is also a base component in many of the AE crafting recipes. When the ore is broken, there is also a chance of Quartz Dust being dropped. If more Quartz Dust is desired, it can be produced by grinding up the Quartz Crystal in one's favourite grinding machine.
It should be noted that in versions of AE released after Minecraft 1.5, due to the addition of Nether Quartz in the vanilla game, all Quartz Crystal will be renamed to Certus Quartz Crystal, to differentiate it from Nether Quartz.
Mod-Specific Compatibility Notes
- BuildCraft - MJ usage, Pipe support, Facade support, Wrench support, certain recipe changes
- Thermal Expansion - additional Pulverizer recipes.
- IndustrialCraft 2 - EU usage, electric tools, additional Macerator and Compressor recipes.
- Factorization - Barrel support
- GregTech - Quantum Chest support
- MineFactory Reloaded - Deep Storage Unit support
- Logistics Pipes (not in Ultimate Pack) - Pipe support
- Minecraft Forge's Ore Dictionary - The Quartz Grind Stone will be able to use existing Pulverizer and Macerator recipes, ensuring the low-tech grinder will work with all ores added by mods supporting Forge's Ore Dictionary
- Universal Electricity - Power Usage (only available in the most current version available for MC 1.5.2)
- OmniTools - The OmniWrench will work like the AE wrench, rotating buses and such as expected.
As far as general compatibility goes, it is very important to note that connecting the central inventory of the ME Network via ME Cable to both import and export buses has the potential to significantly simplify automated activities and projects by providing a central inventory & place where processing is to be done.
In addition, setting up new automation orders and attaching new machines may be being easier for some to set up than other automation systems. It uses a simple GUI that allows 8 items for export or import to be specified per bus. This says what each bus will output or input. Additionally, as buses work directly with machine inventories, you don't have the risk of having chests overflow and having items pop out of machines as entities in large amounts, a positive quality it shares with the Router in Factorization. All of this not only serves to reduce complication on the user's end, but its method of dealing directly with inventories means the impact on game performance is negligible.
This ability to automate is not only extended to the traditionally BuildCraft-compatible mods like Forestry and Thermal Expansion, but also to machines in IndustrialCraft 2, GregTech, MineFactory Reloaded, and more.
While Applied Energistics is able to interact with, store, and move any item you can hold in your inventory, it is important to note that it currently has no support for liquid storage outside of liquids already stored inside items such as a Wax Capsule, a Refractory Capsule, a Tin Can, a Magic Capsule, a Void Capsule or Empty Cells. This means that pipes carrying liquids will not be able to interface directly with the ME Network unless they are first placed inside an appropriate container, generally using a Liquid Transposer, and then inserted into the ME Network.