Snagger's Electricity Guide for New Players

Snagger's Electricity Guide for New Players
This section contains information that I wish I had known when I started playing. Much of it has been discovered by asking for help in the discord. If you still have further questions, remember you can get your questions answered instantly on the Discord at all hours of the day. Many thanks to moronwmachinegun, codewarrior0, Bluebine, Bryfer, and others for their impressive and vast amounts of knowledge that helped make this write-up possible :).

GregTech's electricity mechanics involve 5 concepts you should understand:
 * 1) Voltage (V)
 * 2) Electricity Units (EU) and Ticks (EU/t)
 * 3) Amperage (A)
 * 4) Internal Energy Buffers
 * 5) EU Cable Loss

We'll assume for the this TL;DR (lol) that we're only using the Low Voltage (LV) tier, which has a maximum voltage of 32V. When you look at a recipe for a machine (by clicking on the progress bar in the middle, or by hovering over an ore in NEI and pressing "u"), you'll see the details listed below. For this example we'll look at the Crushed Iron Ore recipe used in the Basic Ore Washing Machine:



Total: 8000 EU Usage: 16 EU/t Voltage: 16 EU Amperage: 1 Time: 25.00 secs

1. Voltage (V)
Voltage is not a finite resource that is used up or stored, but rather a constant value used to determine the tier of electricity/generators/machines. Power generators create power and machines use them. There are 9 tiers of electricity/generators/machines. The voltage a machine receives must be less than or equal to the maximum voltage it can handle. For example, an MV machine has a maximum voltage of 128V, so it can accept power up to 128V, and run any recipes that require 128V or less. If you try to run a recipe that requires more than 128V, it won't run, and if you give it more than 128V, it will catch fire or explode.

The voltage listed in the recipe is the MINIMUM required voltage the machine needs to run this recipe. Since our Basic Ore Washing Machine is in the LV tier and can use a maximum of up to 32V, the recipe for Crushed Iron Ore will run in the machine as long as we supply it with between 16V and 32V. If supplied with less than 16V (ULV provides 8V), the machine won't run, and if supplied with more than 32V, the machine will explode.

2. Electricity Units (EU)
In contrast to Voltage, EU is a finite resource that can be stored, transferred, and used up much like a liquid. You can see in our Ore Washing Machine example that this recipe requires 8000 EU to complete. A tick is the shortest segment of time that we use in Minecraft for all practical purposes, and is equal to 1/20 of 1 second. The usage of the recipe is 16 EU/t, so 8000 EU at a rate of 16 EU/t would require 500 ticks to complete (8000/16=500). 500 ticks is equal to 25 seconds (500/20=25), which you can see matches the time shown in the recipe details.

3. Amperage (A)
Amperage (or amps) can be thought of as packets that contain EU. All generators produce 1 amp per tick. The Voltage and the EU contained in this amp is determined by the generator's tier. For example, an LV generator (let's say a Basic Steam Turbine) generates 1 amp of 32V power every tick. This amp contains 32 EU. In other words, the Basic Steam Turbine produces 32 EU/t.

4. Internal Energy Buffers
Looking again at our Basic Ore Washer example, a hidden piece of information that can only be displayed once you're able to build a scanner is it's internal buffer of EU. All machines have a buffer in them that they draw power from and use to run their recipe. This internal buffer is then replaced and filled back up with EU produced by the generator. The internal buffer for LV machines is 2048 EU.

Amps cannot be split into smaller pieces. Disregarding cable loss (we'll get there next), a 32V amp will always deliver 32 EU. So when a generator connected to a few machines broadcasts "I have an amp I can send out!", the machines will check their internal buffer to see if they have room for 32 EU. If it has empty space in it's buffer, it will respond with "Yes, I have space in my buffer for that amp, give it here!", the amp will be sent, and 32 EU will be added to the machine's internal buffer. Note again that a generator can only produce 1 amp per tick, so if 2 machines respond to the "amp push" of the generator, only 1 can receive the amp, and the other will have to wait until the next tick to receive it's desired amp.

Looking at our Basic Ore Washer example (and disregarding cable loss for now), let's use this chart to track the internal buffer tick by tick:

So when running this recipe, the LV Ore Washer only requests an amp every other turn. So you could run 2 ore washers side by side from a generator that produces 1 amp/tick. An LV Macerator running a recipe that uses 2 EU/t would only request an amp every 16 ticks. You could run 16 macerators simultaneously from a single generator.

Let's look at one more example. This time, let's look at the recipe for Purified Iron Ore in the Basic Thermal Centrifuge:



This one is interesting because even though the voltage is 24 EU (LV tier), it requires 48 EU/t. It will require the use of 2 amps. For simplicity's sake, let's assume there's no cable loss this time.

You can see how this recipe will alternate between using 1 amp and 2 amps every tick. 2 generators would provide enough amperage for 3 LV Thermal Centrifuges to run 48 EU/t recipes simultaneously.

One final thing to note is, and this is somewhat confusing, the machine can accept the amperage displayed + 1 amps every tick. So machines can technically accept different quantities of amps per tick depending on which recipe is being run.

5. EU Cable Loss
Cables are what connect generators to machines, and most cables have something called cable loss. Different cables have different loss amounts, but the idea is that a packet (aka amp) will lose some of the EU it contains for every block it has to travel through. For example, a 1x Tin Cable has a max voltage of 1, a max amperage of 1, and a loss/meter/amp of 1 EU. The amp will lose 1 EU for every block it travels, so if it has to travel 4 blocks from the generator to the machine, it will arrive and only have 28 EU to deliver.

Let's use our Basic Ore Washer example once again to look at 2 examples with different distances between machine and generator to see how this works in practice. Let's assume in the first example the machine is 16 blocks away from the generator and is connected to 2 generators with a 2x Tin Wire with 1 EU/meter/amp cable loss (so that we'll be able to accept 2 amps in a single tick when necessary). We'll use this chart to track the internal buffer tick by tick:

Distance away from generator: 16 blocks

You can see how the buffer would continue to be filled every tick with 16 EU. Pretty simple example. Now for another one with more distance:

Distance away from generator: 24 blocks

Here, there is so much cable loss that after the first 5 ticks of operating, the machine would start requesting 2 amps each tick, and each amp would only end up delivering 8 EU each for a combined total of 16 EU/tick.

Note that the machine is not aware of the cable loss that will occur once the packet arrives, so it requests the amp when it has room for the size of the full packet it THINKS it's going to get, not when it has room for the EU the packet will ACTUALLY contain after cable loss.

6. Useful (and not always obvious) Information

 * Machines require electricity based on the recipe that's being run, not the tier of the machine or anything else.
 * Machines have an internal buffer and the machine draws power from this buffer, not directly from a generator.
 * I'm going to reiterate the last point because I still see veteran GT players do this: they use a transformer to step down the voltage and then run a 4x cable to 4 machines. Unless you're planning on having those 4 machines all run max EU/t recipes constantly, you're providing WAY too much amperage.  Those 4 amps can mostly like supply enough simultaneous amperage and EU/t for 8-12 machines, depending on the machines and recipes of course.
 * The buffer is always refilled by a whole amp and cannot be split into anything smaller.
 * Generators always try to give out their max EU. So the first generator along a wire will drain all its EU first before the second one, etc.
 * Machines in a network will always get their EU from the same generator in the same order. A second generator in a second location may traverse the wire differently.
 * It's a push system, meaning machines don't request amps, but rather generators push amps out along their cable network.
 * Machines can request 1 additional amp than their recipe requires, if they have room in their buffer. The exact formula for how many amps a machine can use is:

So at LV, recipes with 0-15 EU/t accept 1 amp, 16-31 EU/t accept 2 amps, recipes with 32-47 EU/t accept 3 amps, and so on. This is why machines only charge at 1A when no recipe is active.