EA* Plutonium Reactor

  • In my ongoing quest for higher efficiencies out of my reactors, I wanted to build a EA* Plutonium reactor. This was a challenge, as it required a quad plutonium cell, surrounded by neutron reflectors, which produces an immense amount of heat. After several tries, and some melted components, I met with success.

    I am using a modified FTB Unleashed modpack, including IC2 1.116.364 and gregtech. For whatever reason, my plutonium cells produce exactly twice the heat of uranium cells, contrary to what the reactor planner predicts, so bear with my plans saying they overheat. I have run this reactor design for over 72 hours of realtime operation without a problem.

    This is the reactor design

    The 25 Overclocked Heat Vents barely take out the 896 heat/t, with 4 heat to spare. However, they can only dissipate 500 of said heat. Another 32 heat/t goes into the pair of Component Heat Vents. This still leaves a considerable 364 heat/t that gets funneled into the Coolant cells by the Component Heat Exchangers. From here I've used Applied Energistics to automatically remove the coolant cells when they fall below 50% durability, at which point they are placed into a cooling tower from this thread:
    Does This work? (Various Cooling Tower designs)
    Which has an overall cooling capacity of 480 heat/t, more than sufficient for our needs.

  • Further Notes:

    This design is not cheap (requiring what amounts to 2 full reactors of materials, plus 4 iridium plates), but my goal was much more about eu/plutonium than anything else. In fact, the added power needed for the Applied Energistics system ends up amounting to almost half of the added power over a more conventional EA++ design reactor.

    The reason I remove the Coolant Cells at 50% heat, as opposed to a higher amount, is because the surrounding components invariable get heated slightly more, as the heat exchangers are neither perfect nor instantaneous. I had a previous setup melt, when I tried to leave my coolant cells in until 80% heat. All of the cooling components sit at around 50% heat capacity during normal operating conditions. The coolant cells in the top left and right positions get cycled slightly faster, as they are handling 96 heat/t, while the lower cells are getting 64 heat/t. This is part of the reason I don't cycle the cells based of a clock, but instead swap out cells individually. The cells are cycled out of the cooling tower when they fall below 2% heat, to avoid strange effects at very low heat values.

    The 5 separate cooling sections of the reactor are all cooled independently. This has no real benefit, besides allowing the design to fit in a full 25 Overclocked Heat Vents.

    The component heat exchangers do have a limit to what they can handle. However, the highest stress exchangers only need to handle 28 heat/t/face.

    This shows the reactor running. I used NaK coolant cells instead of water cells, because I was initially using a vacuum freezer to cool cells (until I realized how much power that was wasting).

  • I would have to run the numbers to be sure but; I think if you upgrade your coolant cells to their biggest size and then run them in a freezer then it should lower your overhead running cost.

    Alblaka says:

    "People using their intellect in attempts to discuss other people into the ground could be considered less intellectual then people using their intellect for something beneficial :3"

  • Nice design, though I have to wonder is an efficiency of 7 is worth the disadvantages. I'd be tempted to just go for a full-blown CRCS reactor.

    I've gone off CRCS for a while though. I've been unable to come up with a reliable way of removing and replacing the cells correctly. With RP2 in 1.4.7 or AE in 1.5.2, nothing works. These days I just use LZH condensators fed by lapis bees.

    Also, you're right about plutonium producing less heat now. Greg gave it a buff.

  • (...) For whatever reason, my plutonium cells produce exactly twice the heat of uranium cells, contrary to what the reactor planner predicts (...)

    That's because the online reactor planner hasn't been updated beyond GregTech versions 2.8x or evenn earlier.

    I like your design, it thinks outside the box. As a cost-reduction step, you can try to replace the iridium reflectors with single thorium cells. The reactor planner gives you wrong numbers for that, too, but ingame in the computercube it should simulate properly. Doing so should add another 9.6 heat per second, which your cooling cells should be able to accept no problem, if the heat exchangers have enough transfer bandwidth left. In exchange, you gain another 8 EU/t, and you reduce the building cost of the reactor by, oh, about 1,800 pieces of UU-matter.

    As a next step, you should probably design a highly efficient thorium reactor as well. Because, unless you plan to meet your plutonium needs entirely from industrial grinding uranium ore (who knows, this reactor is slow enough to maybe make that possible), you will always end up with thorium on the side if you produce plutonium in the GregTech centrifuge. Because of this dual output nature of the processing recipe, you cannot simply go with the efficiency figures the reactor planner gives you anymore. Not using the thorium produced by the centrifuge will hurt your actual isotope efficiency quite a lot.

    Your reactor on its own here would have an isotope efficiency of just 5.58, for example, despite all the hoops you jump through. If you go and replace the iridium reflectors with single thorium cells from your centrifuge output, it not only makes the reactor cheaper, but also boosts efficiency to 5.74. And yet, the multi-reactor system described in the isotope efficiency post costs less to build than your reflector equipped reactor alone, not counting the cooling tower, has a combined output of 564 EU/t instead of just 280, and posts a combined isotope efficiency score of 5.83, which beats your design as well. And that is why you need a way to consume all that thorium! ;)

    Your design is rated at +16T/20k (16 extra thorium produced per cycle lasting 20k seconds), so you ideally need a thorium sink reactor rated at -20/25k, or -16/25k if you run with "thorium reflectors". Of course, a bigger sink works too, but it will be sitting idle every so often, waiting to fill up on thorium cells. That affects effective EU/t over time, but not efficiency. Multiple small sinks work as well, if that happens to work out for you.

    Ultimately, if you managed to burn all your plutonium at efficiency 7, and all your thorium at efficiency 7 as well (the maximum possible values), you would end up with an isotope efficiency of 8.38, a value so high that no common uranium reactor could ever dream of achieving it.

    The post was edited 2 times, last by Omicron ().

  • I would have to run the numbers to be sure but; I think if you upgrade your coolant cells to their biggest size and then run them in a freezer then it should lower your overhead running cost.

    I actually started out with 360k Helium coolant cells. The vacuum freezer scales differently for water/helium/nak cells, but overall the time used is:
    2 kHeat/Second (Water cells), 2.4 kHeat/Second (NaK cells) and 1.71/1.80/1.85 kHeat/Second (60/180/360K Helium cells). So larger cells don't really help that much, if you're using a freezer. But larger cells would make me need to cycle the cells to the cooling tower less often, which would indeed save some power. I mostly used the smaller 60k cells because I didn't have enough Potassium or Helium.

    I've been unable to come up with a reliable way of removing and replacing the cells correctly.

    I use Factorization routers for inserting fuel cells, and removing coolant cells that accidentally get placed in the fuel slot when the plutonium runs out. Routers can selectively input or output to specific inventory slots in reactors, which is very handy (slots 0-53, going left to right, then top to bottom, treating reactors with less than 6 chambers as full sized reactors, with the extra slots piled on top of each other in the right-hand column). They can get expensive if you need item filters, though, plus you need a different router for every slot.

    Omicron: I agree entirely about using Thorium reactors in parallel. I have 10 set up in my world right now, using:
    Which only has an efficiency of 5.67 (and probably is over-engineered on the cooling, due to the aforementioned discrepancies with gregtech), and uses single cells as pseudo-neutron reflectors. The reasons I didn't use Thorium reflectors for the plutonium design were that first, I had the iridium on hand due to quarrying out huge areas of a mystcraft age, second, the extra heat would have actually been slightly more than my design could handle (9.6 heat being greater than the 4 extra I have), though I could have handled that by replacing the component heat vents with reactor heat vents, and lastly I just liked the idea of a 'perfect' efficiency plutonium reactor.