Hi.
Everyone on my server is powering their machines with a bunch of advanced Gregtech solars. I wanted to prove to my friends how overpowered "free" energy sources (solars, water towers...) really are, especially the advanced versions. So I issued (and immediately accepted myself) a challenge: build a completely sustainable powerplant that would consistently output a non-trivial amount of EU - let's say, 32EU/t.
Here are the specific requirements:
- FTB Beta A pack (so, no RedPower).
- Can not use any "free energy" machines (defined as: place block, get energy forever).
- No exploits/quirks/glitchy/cheap mechanics (energy -> lava -> more energy conversion, burning scrap to produce more energy than needed to create it, etc.)
- Must be 100% self-sustainable. The server runs 24/7, and my base has chunk loaders. If I leave for a week, the system needs to be running all this time. This means no burning nether lava, no netherrack, not even dirt is considered renewable.
- Consistent production of EU. I have "a few" advanced machines, which consume EU by the fact of simply existing. Therefore I need to output a consistent stream of EU at all times, 24/7.
- It should be one coherent system. So no "this setup creates 0.25 EU/t, so I copy it over 120 times".
After about a week I completed a project which fulfills all the requirements. It is a combined forestry/IC/Gregtech factory, with a couple of other mod machines here and there.
First, Forestry farms feeding everything:
Left to right: Peat farm (not needed in the system, but feeds off of it, and I use Peat elsewhere), Tree Farm, Rubber Tree Farm, Wheat Farm.
Every farm sorts its products into an Ender Chest, from which other machines extract it. Any excess is directed into a void pipe, in order not to spill any items when the chest overflows.
Here is my bioplant:
Left to right: Moistener, Fermenter, Iron Tank (Railcraft) with Biomass, Still, Iron Tank with Biofuel, Combustion Engines.
The Moistener receives wheat and seeds from the wheat plant, and turns them into Mulch and Mycelium. The Mycelium is processed by a Factorization Grinder (not shown) into Dirt, which is fed back into the system. Mulch is used in the Fermenter, which receives saplings from the two tree farms and turns them into Biomass.
This is then processed in the Still into Biofuel, which feeds four Combustion Engines. Coolant is provided by Thermal Expansion's Aqueous Accumulators (barely visible under the engines). The engines power the farms, as well as all the machines in this room.
This setup also produces more MJ than needed, and as you can see from the Biofuel in the tank, it could feed even more engines. Although not required by the original challenge, this is also a completely sustainable source of BC energy. (I haven't done the math of how much of it is produced, as the MJ needs of Forestry machines are largely unknown.)
Carpenter room:
Pretty simple, a pair of Carpenters creating Bog Earth and Humus from Dirt and Mulch generated from the system, and Sand created by macerating Cobblestone from an Ingeous Extruder (not shown). The version of Forestry in Beta A has a bug, and Carpenters can't be fed by pipes. I solved this by using Routers, instructed to deposit items into specific slots. Buildcraft gates manage extraction from the Carpenters so that the Ender Chests never overflow.
(The bits at the right side are from something else (bee products processing).)
Finally, the IC/GregTech powerplant (a.k.a. The Beast):
All GregTech item-moving machines lose their textures when I leave the server. But the signs explain how the individual machines are connected. The following process is used:
Industrial Centrifuge: 12x Empty Cell + 16x Rubber Wood + 25,000 EU --> 8x Sticky Resin + 6x Plantball + 4x Methane Cell + 1x Carbon Cell
Industrial Centrifuge: 8x Sticky Resin + 12,500 EU --> 28x Rubber + 2x Compressed Plants + 2x Plantball
Rubber is discarded into a void pipe (I have a barrel full of it already).
All Plantballs are compressed into Compressed Plants.
Compressor: Plantball + 800 EU --> Compressed Plants (this is used 8x every cycle)
The Carbon Cell is extracted to get an empty cell back. (There is no sustainable way to get energy from Carbon. Turning them into Methane cells consumes one cell.)
Extractor: Carbon Cell + 800 EU --> Empty Cell
Crafting: Compressed Plants + Empty Cell --> Bio Cell
Methane Cells and Bio Cells are deposited into an Ender Chest, to be used by machinery on the right side of the room:
Industrial Centrifuge: Empty Fuel Can + 6x Bio Cell + 5,000 EU --> Fuel Can (26,040 EU) + 6x Empty Cell (this happens 5x every 3 cycles)
Industrial Centrifuge: Empty Fuel Can + Methane Cell + 1,000 EU --> Fuel Can (45,000 EU) + Empty Cell (this happens 4x every cycle)
Empty Cells are returned back to the system through an Ender Chest. Note that during one cycle, we get all the used cells back, so the system doesn't eat any tin.
Fuel Cans are distributed by Factorization Routers (very right edge of the image) between 6 Generators to generate fuel. A fuel can, unlike a cell, is not consumed by the Generator. Another Router then picks the empty cans up and inserts them back into the centrifuge to be filled.
Summing it all up, one entire cycle of the system consumes only 16 Rubber Wood. No additional resources are required, all other materials used are returned. One cycle creates on average 223,400 EU. Subtracting the running cost of all machines needed to process various items, every cycle nets 166,366 EU. (Note, this does not account for power needs of GregTech Translocators and Sorters, which is however negligible).
Looking at the time the various operations need, centrifuging the rubber wood is the bottleneck - it takes 250 seconds. All the other components can easily keep up. Therefore the whole setup produces, on average, 33.27 EU/tick.
Obviously I don't claim that this is anything resembling efficient. In fact this setup could probably compete in a Rube-Goldberg Machine contest. But it fulfills all the original demands - a 100% sustainable energy source, which does not rely on any glitches, quirks, or inter-mod balance issues. And I had loads of fun figuring out the needed processes, building the machines, and optimizing all pipes and item transport.
Some final notes and other random thoughts:
* In addition to EU, the system produces all sorts of byproducts: BC power (MJs), Wheat, Seeds, Peat, Wood (Oak and Rubber tree), Dirt, Mulch, Biofuel, Rubber. All of these are generated in larger amounts than needed, therefore the setup is also an infinite source of all these things.
* The IC setup creates 10,397 EU per piece of Rubber Wood. I know turning regular wood into Scaffolds would create more, however I consider burning Scaffolds a very cheap mechanic balance-wise. (One of those I didn't want to abuse.)
* It is not energy efficient to convert Bio Cells into Biofuel Cells (in Beta A). It costs less to centrifuge Biofuel Cells into cans, but the difference is not enough to cover the Extractor power cost.
* Ender Chests are really, really powerful when it comes to compacting your piping. The entire setup contains maybe 40 individual pipes, vast majority of that is used by Forestry farms. They are needed there because the farms are really really dumb, and there is no way to sort their outputs other than pipes. I would absolutely love a TE-style interface to send, for example, saplings from one side and wood from another.
* At one point I had the excess Biofuel transported into Bio Generators. I found out they use a LOT of it. So much that even one ate all the excess fuel. I could just spam a bunch of tree farms to produce more saplings, but that would use much more space, and go against the "no copying a weak setup" requirement.
* The GregTech room causes a very significant FPS drop whenever I'm near it. I have no idea why.