How to preheat your breeder

I'd like to present this as something of a comprehensive guide on both available and preferred methods of heating up a reactor.

Methods:
1. Lava buckets
2. Heating configuration
3. The art and science of precise heating.

1. Lava Buckets

I'll start with BE CAREFUL! because people often have to make thier own mistakes, but I'll also go into DON'T DO THIS!
As this is a typical breeder, I'll be using it as an example: http://www.talonfiremage.pwp.b…i=1m101010114010101001019

A lot of people explode their reactors when they try to use this method because they don't have a good understanding of how it works! How do people make this mistake? Well, you set up a configuration you see, say for a perfect breeder with 4 chamber 23 cooling cells and 7 heat dispensers. All this work into all those parts, and now you will finally get the increase in uranium yield you've been working towards. Now it's time to add lava buckets. Maybe you know how many you are supposed to add, maybe you are just winging it. Maybe you know that lava adds 2000 heat to the hull, maybe you don't. Maybe you know it's supposed to be somewhere around 9k for breeding. So, you add buckets. And nothing visible happens. So you add more. And you see the particle effects of smoke. You're looking at the parts, and they aren't getting hot. Maybe the smoke goes away, maybe the fire particles turn back to smoke, but it seems like you aren't making progress. Maybe this is when you find out you need > 240 buckets of lava to heat this config. So you add more lava. Still not really making progress it seems. So you start putting in a few at once. The first 2 you put in are fine. You put in 2 again, its fine. You put in 2 again its fine. You put in 3... Still the parts aren't getting hot. this is taking forever. If you were this patient, when you put in 3 again you will start being irradiated and have to flee the reactor room. If you were slightly less patient and bumped up to intervals of 4 or 5, you probably blew everything up. I irradiated myself this way, plenty of people have this exact experience. This is pretty natural behavior... don't do it though.

Lava buckets add 2000 heat directly to the hull, the part that is responsible for the meltdown. Hulls have 10k to 16k capacity for heat, depending on the chambers. 5 buckets of lava AT ONCE will vaporize a zero chamber reactor, no matter the cooling config, make a 2 chamber reactor go critical (chance of meltdown, or melting nearby blocks)or start radiation burn in up to a 4 chamber reactor. 8 buckets at once vaporizes all reactors. So how are you going to add the 240+ lava buckets that it needs to heat up to the right temp? Instead of adding them at once... add them over time. Heat dispenser pull heat from the hull into themselves, and transfer that heat to the cooling cells next to them. They try to equalize their temperature to the hull temperature, but each can only suck 25 heat out of the hull per second. When you start by adding a bucket of lava, waiting ~11 seconds and adding a second one, nothing visible happens, but each dispenser sucked in about 275 heat, dispersing that among ~4 to 5 available parts and reducing the hull temp from 2000 to around... 50 or so. so each part & the hull is now around 50 heat, which is not enough to move any bars or make anything visible happen. What you are supposed to do is continue adding 1 bucket every ~11 seconds to keep this increase flat and linear, 240+ times. That is 44 minutes of adding lava. That same 240 buckets of lava in a geothermal would net 4.8 million eu. People do not do this. Those that know, do not use this method, those that don't know... They overload the heat dispensers. As nothing visible happens, you think it can handle more. When you go to adding 1 every 5 seconds, the hull is gaining ~1k heat for each you add. When you take a second to ponder, it might catch up a bit, but when it catches up, still likely you have not made enough of a dent in what is required to move bars. So more lava faster gets the particle effects, because the hull can't shunt heat fast enough, and when yet more is added, the nasty happens.

If you haven't tried this method, save yourself the trouble.
If you want to know why it's hard to make this work it's because time is needed for each part to receive the heat you are adding to the hull, and the total heat needed includes the parts 30 parts + hull to 9k heat. 279000 total heat with the ability to dispense slightly less than 175/s. 44 minutes of pouring 4.8million geothermal energy down the drain.

2. Heating configurations

Most people graduate to this method when they realize that buckets of lava are less than reasonable. It's premise is simple. Efficient consumption of fuel generates lots of heat. Set up a energy producing config to produce heat, then switch to breeder config when it gets hot enough.
This method is much simpler, and somewhat safer. It is still not entirely safe.

There is a trade off between safety and time. The safest way would be to set up a mark II config that runs for 1.05 cycles, and show up right when it finishes, almost 3 hours later. 3 hours to "heat up your breeder" no chance of explosion. Just pop in the breeding config using the hot parts and you are golden. Most of us don't want to wait 3 hours, but if you are a planner you can make that work. Most people set up a mark IV config and let that run for a bit, then when it gets hot paying closer attention to it. Heating configs should have the same number of cooling cells as thier breeding configs have, and enough dispensers to soak all of the heat generated. Heating up the parts is kind of the point of heating up your breeder, do not set up configs that overwhelm heat dispensers, the reactor will explode before the parts are hot. Divide the heat generated by 25, and add 1 to be safe. Cooling cells can't be next to extra hot uranium, and you get bonus points if most of the parts can stay in the same place between configs.

For example:
http://www.talonfiremage.pwp.b…c=1m101010114110101001019 Breeding config
http://www.talonfiremage.pwp.b…g=1m101010114010101001010 Heating config

So you run the heating config for ~40 minutes, then swoop in and change it up to breeding config. Note that this is around .25 cycles with 4 uranium. This means heating it up this way takes about 1 uranium, but that uranium is consumed with efficiency of 3 with 120 eu/t output with around 6million energy produced. The istopes in the heating config do not breed very well during that time, they are mainly there to pump up the heat produced.

You can substitute other energy efficient designs, as the heat that is their waste is the real goal, but keep an eye on how many hot parts you need in your breeding config. Heating up 16 dispensers and 15 cooling cells would mean you have to swap in 8 cells from storage. If those aren't simlarly hot, you'll have to heat them up by running the heating config more.

Some may be surprised that heating via mark IV config and heating by pouring lava take a similar amount of time... but it all comes down to how efficiently heat is dispersed among the parts. With the same number of heat dispensers, heat is distributed at the same rate. Adding more heat will not heat the parts faster, it will just heat the hull to explosion

Remember when I said this wasn't exactly safe? I believe it to be what most people do, but... You are setting up a mark IV to run for >30 minutes unattended. This takes time management skills, or some other kind of safety mechanism (like my chicken kill switch) because @ 30 minutes you have pretty good breeding, but should probably let it sit for a while. At 40 minutes you have very good breeding, time to reconfigure. At 50 minutes, you have a crater. So yeah, heating up a reactor with uranium takes a heat generating config. Heating it up with a config as quickly as is possible means generating heat as quickly as it can be dispensed. Leaving a reactor that is generating heat quickly alone for too long means boom.

3. The art and science of precise heating

In this section, I am going to go into when you might want to precisely heat a config, how to heat individual parts, and a tense game I like to play with a mark IV breeder on a short fuse.

You may have realized by now that you could save a lot of time/energy if you stored one set of hot parts for breeding and cool set for energy generation. Invariably, the energy generation ones get hot and the breeder ones cool and the stored ones end up mediocre heat. At some point, you have to reheat parts that are at unknown starting heat, and you either give up on storing hot parts, sit on the reactor for 15-30 minutes watching it like a hawk, or figure out how to precisely heat different types of parts. I went with that last one, and I am going to share with you how you can do so. This offers a benefit for 2 reasons. First, as mentioned, reheating those parts for that breeder config. 96% of the work is in those stored parts, if all that was cold was the hull, that is just a few buckets of lava and problem solved. Secondly, with a little math, you can use those hot stored parts for precision heating.

... to be continued.

Continued.

With precision heating, you can set up a positive breeder as a mark II. This allows you to design energy producing configurations that breed isotopes, hybrids that essentially run on isotopes. Breeding requires heat, so to breed efficiently, you want to end the cycle as close to max heat as possible (risking meltdown). Positive breeder designs that start cold are much less efficient, as they spend less time in the breeding sweet zone and take more time to cool down. The hotter you can start a hybrid, the more efficiently it breeds, and you can drive that efficiency gained into energy production. If you don't know what heat you are at with some precision, knowing whether you are starting a mark II positive breeder hybrid or mark IV positive breeder hybrid is something of a crap shoot. If you know your system is starting at a dispersable 45% heat and generates 45% heat during operation, you know its a mark II. When you come back to decent energy efficiency and 1 refined isotope / uranium consumed, you start to understand why this benefits you.

When we are heating up parts, we don't want to fight external cooling. 5 lava is enough to cancel external cooling entirely. Isotopes will generate heat even while the reactor is off, so with designs that include isotopes, I include external cooling to offset the heating, leaving the hull a constant temp when it is not in operation

Heat dispensers -
Impossible to heat up seperately, as they are tied to the hull. Most of them will be sucking 25 heat /s from the hull, ones adjacent to hot uranium are a bit harder to work out. Nearby adjacent could be dispensing/absorbing heat, but in practice only do so to correct a heat imbalance, like if they started at different temps or one is next to hot uranium. At 400 seconds to melt if enough heat is being generated, I tend to pop in all the ones I need and heat them all up at once with no cooling cells. With a hull constant config and no cooling cells, they don't cool when you shut the reactor off. You should shut the reactor off when you store these, or it will explode, as removing them means the remaining ones will be overwhelmed and not remove heat from the hull as fast as it is being generated. Figure out how much dispensers your config needs, multiply by 25 and that's the heat the dispensers can keep up with. Make a config that comes in at UNDER that heat, the closer the better for example 14 dispensers would be http://www.talonfiremage.pwp.b…g=10101015114010101001010. Remove external cooling with lava, hit the on switch, and wait for the last red dot to disappear. THEN HIT THE OFF SWITCH OR BOOM. This also preheats the hull to this amount. I do this first for a hot hull for the next step.

Cooling cells - Heat dispensers are bad, but cooling cells are worse. They are actively working against our goals of heating. They do not seek out or accept much heat. A cooling cell next to 1 dispenser heats up by ... 5/s that is 2000 seconds if it is next to just one dispenser to heat up. This is where the 40 minute heat up time comes from. We can do better than that. If we surround it with dispensers, we get 23/s (only while the cell is much cooler than the dispensers), which is still ridiculous. That's longer to heat up than the dispensers, at a ratio of > 1 dispenser per cooling cell. So to efficiently heat up coolant cells we have to feed them heat from uranium. Which is fine, since we don't want that heat going to the hull, no dispensers are removing it. You can pop a coolant cell in 60 seconds. I came up with a faster design that kills a coolant cell in 25 seconds... but we can use neither of these designs, because for 1 we don't want to flip the on off switch each time we switch out a cell, and 2.) 390 heat into 1 part is too much! I came up with a design I call Crazy Ivan, just for this job. With the hull already at ~9k from the last step breeding effectiveness should be good, and as long as the plating lasts, no heat goes to the hull. The idea is, when the last spot of red disappears from the bar of the coolant cell, pop a cooler cell diagonally from it, and pick up the hot one and put it in your inventory, not the reactor. Repeat until you have the number of hot coolant cells you need. At 160 heat/s into cooling cells, this is more efficient at heating cooling cells than a checkerboard of 19 dispensers and 10 cooling cells. This is a manned configuration, you do need to have your finger on the button for as long as it takes to heat up each cell, up to 1 minute per cell, less for reheating warmed ones.

From a cold start, this method has reduced warm up from 45 minutes to 30, and gives a much greater level of precision for reheating warm parts. With hot parts stored, you can do your normal breeding run. You could also use a mix of hot and cold parts for a target heat. For example, I want to target 5k starting heat for a positive hybrid breeder. 47 parts + 1 hull, If I start with 24 hot and 24 cold, I get 5k (really 4.5k, as the parts are more like 9k hot than 10k) heat average that can be dispensed during operation. With that hybrid design, I would heat the 13 dispensers and the hull, then crazy ivan 9 coolant cells for a warm up time from cold of around 25 minutes.

If you have a method I haven't mentioned, or any refinements, please don't hesitate to chime in.

Quote from Vudic

First I would like to thank gorzak for this fine tutorial.

I tried to rebuild your setups and now I have a few questions, if you don't mind:

1) After 40 minutes of heating I see small flames coming out of the hull. I then switch to breeding config. How long does it take to re-enrich the 4 near depleted cells? Full cycle? Half Cycle?

It does not take a full cycle. With good hull temp, 1/4 - 1/2. I'd like to give a finer answer, but it has been a while since I got my hands dirty with it, I been playing hardcore for a while.

Quote from Vudic

2) If the cells are re-enriched and the uranium cell is used up - does the reactor keep it's temperature or does it cool down again?

This might not be 100% accurate, because I have not devised an effective test, but my observations indicate that a re enriched (completed) isotope behaves about like an empty slot. I am sure the parts start cooling if you don't replace it with another depleted one. I suspect it is because it no longer causes the adjacent uranium to pulse an additional time, lowering the heat generated. This would also cause the remaining isotopes to breed less efficiently, as they are receiving fewer pulses. When the uranium is consumed, or the reactor is shut off, cooling continues inside the reactor. Cooling always continues inside the reactor.

Quote from Vudic

3) After my first try I removed the Uranium cells out of the chamber. I returned later to restart the testing - the hull still emits small flames but the cooling parts in the chamber are again nearly half "filled". Do I have to restart with heating config, even if the hull emits small flames?

Typically yes... with a stipulation. Efficient breeders have heat dispensers. If you do, you do need to return to the heating config. If you don't have heat dispensers, then hull heat is disconnected from parts, and then no, don't heat it more. If you are doing this, it would be wise to design the the external cooling such that the hull heat never changes. No heat dispenser designs have an easy heating stage but cannot be as efficient and do require babysitting.

Quote from Vudic

4) How can I find out that I have reached the OVER 9000 when the reactor is in "half heated" stage and the temperature masurement mod ist not installed?

I don't use temperature mod either. The easy way: Your heat dispensers are connected to the hull. If there hasn't recently been an quick event to drastically change it's temp (Lava, ice, water, putting a cold or hot dispenser in with the opposite temp hull), it will be a fairly accurate visual representation of hull temp. If it has been chugging away heating using a heating config, or slowly cooling itself while you've been away, the hull temp matches the dispenser temp. Switch to a heating config, and when your dispensers are about to pop, your hull is at the same temp (but has a higher maximum hp). The dangerous thing is short term drastic changes cause the dispensers to no longer accurately reflect hull temp. They take a while to catch up to what the hull is doing if the change is not gradual.

Quote from Vudic

Thanks alot!

Best regards, Vudic

You are quite welcome.