Electrolyzers and heat destruction

[SpeedDaemon]

Only on my second game so far, and looking into methods to cool the base long-term.

I've been doing some math with the electrolyzer and it's constant heat output to see what the rate of heat destruction could be.

The electrolyzer converts 1000g of H2O into 888g of O2 @ 70C and 112g of H2 @ 70C.

For the sake of these calculations, assume the water going in is just below boiling (95C).

If I just do a simple 1000g x 25C delta x 4.179 specific heat, I get 104,475 J/s heat loss (~104kW, which is crazy high for a single building)

The problem is, the outputs have different specific heats, so that wouldn't be entirely accurate. But, if I switch from Celsius to Kelvin to work in absolute values and account for individual specific heats, things get totally insane.

1000g H2O @ 95C/368K, or 1000g x 4.179J/g x 368K == 1,537,872 J of heat energy in the input.

1000g H20 @ 70C/343K, or 1000g x 4.179 J/g x 343K == 1,433,397 J (same delta 104,475 J as above, so that part is consistent)

888g O2 @ 70C/343K or 888g x 1.01J/g x 343K == 307,629 J of heat energy in the O2 output (that 1.01 specific heat is where the magic happens, I think)

112g H2 @ 70C/343K or 112g x 2.4 J/g x 343K == 92,198 J of heat energy in the H2 output

That puts the energy delta at 1,138,045 J/s (1+MW)...Why is the electrolyzer not glowing like a lightbulb??

So, if you can water cool your base (with the "hot" areas designed to run hot enough to bring water to boiling/near boiling), and use the coolant for electrolysis, one electrolyzer could cool the whole base? Either that, or I'm missing something important...

[trukogre]

104 kW isn't very much thermally in ONI, by comparison:

entropy device: 400 w * 200 hidden multiplier - 80 kW of cooling

tepidizer 20k * 200 hidden multiplier - 4000 kW of heating.

 

The real problem with trying to cool your base with an electrolyzer with your scheme is that if part of your base is hot enough to bring water to 95 C, then either your whole base is way too hot, or you just have a lot of localized heat from a ton of concentrated industry.  Either way, you're not cooling your whole base effectively with that cooling.  Now, what if instead of heating water passively, you're using an aquatuner?  The problem with that is that if you're using an aquatuner for cooling, it's more efficient to sit the aquatuner in polluted water, since you have ample sources of colder polluted water, and then you want to use hot clean water for the electrolyzer, but there you might as well use geyser water which is generated at 95 C to begin with.  An aquatuner that you run polluted water through, and which is sitting in polluted water, provides 6 spec heat * 10000 grams /second * 14 degrees = 840 kW of cooling, and you can dump the hot pwater into fertilizer makers, water sieves, or into a pwater boiler, whatever you please.

but, i mean, for the short period of time until you find your first steam geyser, if you're using an electrolyzer and you need cooling, it wouldn't hurt to try to warm that water up first. it just doesn't make sense to do anything but use steam geyser water to feed to electrolyzers once you find them.

 

p.s. I don't use absolute (kelvin) for spec heat calculations if i can help it, the numbers are ridiculously high and don't really reflect the real impact on the game world.  if you think the numbers for the electrolyzer are high, look at the relative and absolute spec heat for the following machines/processes:

A:  A water sieve into which you're feeding 120 C polluted water at 5 kg/s (fixed output is 40 C clean water)

B: starting with 100 kg of 20 C polluted water, heat it up to 120 C where it boils and turns into clean water, cool the clean water back to 20 Celsius.  Analyze how much joules this absorbs or emits to the rest of the asteroid, as well as the change in inherent heat energy of the water.

 

You could just look through my post history and probably find the calcs already done somewhere, but it's probably faster to just run them.

[Oozinator]

13 minutes ago, trukogre said:

..if you think the numbers for the electrolyzer are high, look at the relative and absolute spec heat for the following machines/processes.

[SpeedDaemon]

Ah, that sneaky 200x multiplier that isn't mentioned anywhere is apparently the "missing something important" bit. Thanks for pointing that out.

Also didn't realize the sieve had a constant output, too. The electrolyzer was the only machine listed with output temps on the wiki.

Still, though, most buildings' waste heat is only listed as 5-10W (or 1-2kW taking the sneaky multiplier into account). Dumping 1MW via an electrolyzer that you'd be running anyway still could account for 500-1000 machines worth of heat (unless I'm STILL missing something important).

After some additional calculations, I think the craziness from my OP is the reason these buildings have constant temp output in the first place. If energy was conserved properly, putting 25C room-temperature water into an electrolyzer would result in your O2 coming out at 698C, and the H2 at 1,116C.

The reason I suggested running the heat-generating areas of the base as hot as they can stand is that it would generally mean less map area to cool, and also heat transfer to coolant is faster the larger the temp delta is. Those areas would be completely separated from anywhere the dupes are supposed to be on a regular basis.

38 minutes ago, trukogre said:

if you think the numbers for the electrolyzer are high, look at the relative and absolute spec heat for the following machines/processes:

A:  A water sieve into which you're feeding 120 C polluted water at 5 kg/s (fixed output is 40 C clean water)

B: starting with 100 kg of 20 C polluted water, heat it up to 120 C where it boils and turns into clean water, cool the clean water back to 20 Celsius.  Analyze how much joules this absorbs or emits to the rest of the asteroid, as well as the change in inherent heat energy of the water.

A: About 1.65MW for 115C input (or just 30kW per degree C above 40). Very nice, especially if you're using a sieve anyway.

B: Just over 180kW for 1kg/s throughput.

In any case, it seems like it could be worthwhile to scavenge all the waste heat you can, and dump it into the inputs of electrolyzers, sieves, etc., since they just magically disappear it.

[Saturnus]

If you really want to cool something effectively then make a Borg cube supercooler

[trukogre]

1 hour ago, SpeedDaemon said:

Ah, that sneaky 200x multiplier that isn't mentioned anywhere is apparently the "missing something important" bit. Thanks for pointing that out.

Also didn't realize the sieve had a constant output, too. The electrolyzer was the only machine listed with output temps on the wiki.

Still, though, most buildings' waste heat is only listed as 5-10W (or 1-2kW taking the sneaky multiplier into account). Dumping 1MW via an electrolyzer that you'd be running anyway still could account for 500-1000 machines worth of heat (unless I'm STILL missing something important).

After some additional calculations, I think the craziness from my OP is the reason these buildings have constant temp output in the first place. If energy was conserved properly, putting 25C room-temperature water into an electrolyzer would result in your O2 coming out at 698C, and the H2 at 1,116C.

The reason I suggested running the heat-generating areas of the base as hot as they can stand is that it would generally mean less map area to cool, and also heat transfer to coolant is faster the larger the temp delta is. Those areas would be completely separated from anywhere the dupes are supposed to be on a regular basis.

A: About 1.65MW for 115C input (or just 30kW per degree C above 40). Very nice, especially if you're using a sieve anyway.

B: Just over 180kW for 1kg/s throughput.

In any case, it seems like it could be worthwhile to scavenge all the waste heat you can, and dump it into the inputs of electrolyzers, sieves, etc., since they just magically disappear it.

"Ah, that sneaky 200x multiplier that isn't mentioned anywhere is apparently the "missing something important" bit. Thanks for pointing that out."

Yeah, that's the main thing people learn when they come to the forums.  Probably because it's not mentioned anywhere in game.

"Also didn't realize the sieve had a constant output, too. The electrolyzer was the only machine listed with output temps on the wiki."

Carbon skimmer constant output 30 C as well. Wiki's not very up to date, and generally something's changing every patch, lavatories and showers output temps just changed in the last patch for example, old: the temperature of the machine new: the input temp.

"(unless I'm STILL missing something important)."

  well, like i said, eventually I think you'll realize it's easier just to run all your electrolyzers on geyser water, which is actually generated right at 95 C once you insulate the geysers.  

"After some additional calculations, I think the craziness from my OP is the reason these buildings have constant temp output in the first place. If energy was conserved properly, putting 25C room-temperature water into an electrolyzer would result in your O2 coming out at 698C, and the H2 at 1,116C. "

If you look at electrolyzers in real life, the lowest temperature type operates right at 70 C, which seems like not a coincidence.  We can say there are a number of good reasons for the 70 C fixed output.

"B: Just over 180kW for 1kg/s throughput."

starting with 1 kg of polluted water, you need 1000 grams * 6 spec heat * 100 degrees = 600 kJ to raise it to boiling-ish at 120 C.  Back down to 20 C, 4.18 * 100 * 1000 so 182 Kj less to cool it.  This demonstrates why the specific heat of polluted water should be 4.18, or maybe 4.10, not 6.  6 is insane.  This shows why they changed showers and lavatories to output at the input temp, instead of their own temp.  It used to be you could cool your whole base just by boil purifying the output of a few showers and your lavs.  But, look at carbon skimmers.  30 C fixed output running 500 g/s worth of water through carbon skimmers  and then boil purifying the polluted water back to clean is a nice cooling cycle, if you're not just using slicksters.  500 * 6 * 90 270 kW, then you only have to cool it down to 90 C before running it into the carbon skimmers.

That's a lot of math, I still haven't mentioned how I cool my own base.  I generally first thing go find an entropy device and set up some electrolyzers by it, since that's quick.  Once I get that built, I go make some of the 'ample sources of cold polluted water' I mentioned earlier.  What are those?  Natural gas generators and petroleum generators currently generate their outputs of polluted water and co2 at their own temperature.  So, cool them to -20 C, and they put out a ton of -20 C polluted water.  These generators are a huge noob trap, if you let them run hot they generate even more heat; but if you run them properly they generate polluted water so cold you'd be hard pressed to heat it all up without gratitiously using tepidizers.

ps. the borg cube supercooler saturnus points out appears to use the 'cooling from above' exploit which is the most powerful cooling method currently available while clearly an exploit; if you're not familiar with it basically a small amount of cold liquid on top of a large amount of hot liquid will cool the hot liquid down up to thousands of times more effectively than it should. Obviously this is so easy to exploit that's it's actually harder to avoid using it than it is to benefit from it by accident.  I don't call it an exploit as a criticism of him or it, we all know the exploit and it's a single player game with an easily accessible debug mode, I'm just laying it out for you clearly since it's one more thing not documented ingame.

 

 

 

[Pex]

Mate, @SpeedDaemon! Just leave the "theoretically bu******it". It could be interesting, but meanwhile you forgot to "play" and having fun.  

Just build a "cooler room" at middle of your base as Saturnus suggested, or plant few weez, or grab ice, set containers to 100Kg, and melt them into a basin at middle of your base. No need those numbers... Some times less is much. You shouldn't want to over-speculated this.

The closest for you topic would be if make these "cooler tanks" where your electrolyzers setups are, so you can cool down your output oxygen which will cool down your whole base.

 

You can do it!

 

[Saturnus]

25 minutes ago, trukogre said:

ps. the borg cube supercooler saturnus points out appears to use the 'cooling from above' exploit which is the most powerful cooling method currently available while clearly an exploit; if you're not familiar with it basically a small amount of cold liquid on top of a large amount of hot liquid will cool the hot liquid down up to thousands of times more effectively than it should. Obviously this is so easy to exploit that's it's actually harder to avoid using it than it is to benefit from it by accident.  I don't call it an exploit as a criticism of him or it, we all know the exploit and it's a single player game with an easily accessible debug mode, I'm just laying it out for you clearly since it's one more thing not documented ingame.

If you want to know how much the borg cube cools then it's 6000kg of petroleum and 2000kg of iron going from +70C to -40C in 11 seconds on normal slow speed. 

[trukogre]

1 hour ago, Saturnus said:

If you want to know how much the borg cube cools then it's 6000kg of petroleum and 2000kg of iron going from +70C to -40C in 11 seconds on normal slow speed. 

Lol I figured it was something obscene but that's ridiculous

 

@Pex "Just leave the "theoretically bu******it". It could be interesting, but meanwhile you forgot to "play" and having fun.  " 

Hey Pex, you forgot that you don't have a camera in his room so you don't know if he forgot to play or if he's having fun, you're just spouting nonsense.   If you don't like math, just stop reading.  You can do it!

[FIXBUGFIXBUGFIX]

9 hours ago, SpeedDaemon said:

If energy was conserved properly, putting 25C room-temperature water into an electrolyzer would result in your O2 coming out at 698C, and the H2 at 1,116C

Nope!

Q=cm△T applies only to heat transfer without phase transition and chemical reactions.

Never use this formula to calculate absolute heat!

9 hours ago, SpeedDaemon said:

Also didn't realize the sieve had a constant output, too. The electrolyzer was the only machine listed with output temps on the wiki.

 

[trukogre]

29 minutes ago, R9MX4 said:

Nope!

Q=cm△T applies only to heat transfer without phase transition and chemical reactions.

Never use this formula to calculate absolute heat!

Luckily, ONI doesn't have any energetic phase transitions or chemical reactions, so, something something morbs something.

[FIXBUGFIXBUGFIX]

2 minutes ago, trukogre said:

Luckily, ONI doesn't have any energetic phase transitions or chemical reactions, so, something something morbs something.

ONI still have phase transition. Since Ice and water have different specific heat capacity, it's still unwise to calculate absolute heat.

But don't forget it's just a game. Take it easy and have fun.

[trukogre]

2 hours ago, R9MX4 said:

ONI still have phase transition. Since Ice and water have different specific heat capacity, it's still unwise to calculate absolute heat.

But don't forget it's just a game. Take it easy and have fun.

Ah, i see what you're saying, he didn't account for the different specific heats in the different phases.  I thought you were referring to the real world scenarios where you have transition energies and then in certain states the specific heat varies with temperature and pressure and such.  My bad.

[Zarquan]

What you can to do is you could cool gold amalgam thermoregulators with water destined for the electrolyzer. That would directly delete heat and I could easily see the water getting over 90C.  You take the 70C O2 from the electrolyzers and run it through the thermoregulators to get the O2 to a decent temperature. 

[avc15]

23 hours ago, trukogre said:

if part of your base is hot enough to bring water to 95 C, then either your whole base is way too hot, or you just have a lot of localized heat from a ton of concentrated industry.  Either way, you're not cooling your whole base effectively with that cooling.

 

Remember this game is an engineering sandbox, and try not to speak in absolutes. The OP's idea is sound, and I know because I'm doing something similar. It's really pretty strong. But heat deletion is cheating tbh, mass consumed and produced should input its heat into the building it's going through. IE I expect this kind of thing to get patched; the only kind of heat deletion that seems intended to me happens inside the entropy device.

So here's what you do: build an insulated water tank outside the insulated part of your base, even insulated from your power generating equipment.

Move all the hot water from your geysers to this "hot tank", and keep it topped up using a pressure sensor controlling the liquid shutoff on your fill line. (this water line costs a fair bit of abyssalite)

Criss cross the hot tank with diamond tempshift plates, and build 3 aqua tuners in series inside it.

Build another "cold tank" inside your insulated base, filled by running geyser water through your aqua tuners. (rejecting the heat from said geyser water into your hot tank before it's stored inside your base) You need a thermo sensor deciding when you're pumping and when you're not, to keep the water temp below boiling. 

--

So what about the heat rate? I'm running 8 electrolyzers - if I've managed pretty good efficiency on them, this will be: 7100 g/s oxygen and 900 g/s hydrogen produced at 70C (the hydrogen gets deleted into entropy devices and h2 electrical gens); 8000 g/s water consumed at 95C. That's about exactly the amount of water you can get out of 2 steam geysers, over time.

Heat balance: [oxygen] [273K + 70C] * 1.01 J/g/K * 7100 g/s - [water] [273K + 95C] * 4.179 J/g/K * 8000 g/s ~~ up to 10 million joules per second deleted depending on what kind of throughput you can get from your electrolyzers.

this is a kind of bogus heat balance because no such thing ever occurs in real life. But, that's a pretty powerful heat sink.

I have run into some challenges making it stable, though. Note the tuners breaking even though the water temp is well below boiling and the aquatuner itself is cool enough that it shouldn't be taking damage:

 

13 hours ago, R9MX4 said:

Nope!

Q=cm△T applies only to heat transfer without phase transition and chemical reactions.

Never use this formula to calculate absolute heat!

 

A life lesson I learned as a professional engineer: resist speaking in absolutes. It improves your business value!

It's really hard to model what's going on in ONI in any meaningful way, because I can't think of a way to connect the beginning state to the end state in an energy balance. So it's better to discuss why there are problems with notions of absolute heat, and see if there's a way to build a meaningful model anyway.

In real life I agree with your statement. In this game, however, I think it's ok to use Q = cmT looking at how many joules vanished or appeared with a material. Because, the game magically replaces one material in some phase and temp with a different material in an incomparable state. Even if the game knew about enthalpy of reaction, and even though it does know about latent heat, neither of those things become involved.

We don't have to reduce the material to 0 kelvin before deleting it, or heat it from 0 kelvin before printing it into the world. No heat exchange, chemical change, or phase change. A material was in liquid phase at some temp, it vanished - another material didn't exist at all, but now exists in gas phase.

If this kind of thing ever happened in real life we might actually use absolute heat calculations once in a while. Probably with some extra restrictions in place to make sure our results were sane (I think we'd look at rate of specific heat capacity change before deciding whether temp is going up or down). Like I said, it's a bogus heat balance. But this isn't life.

Where this COULD go wrong is in being misleading - it could be possible to remove heat and also increase the world's temperature at the same time. Or vice versa. Because, no conservation of mass or energy - like, if over time you were actually reducing the world's specific heat capacity. That shouldn't be happening in this case because geysers replenish water as fast as I'm using it.

I guess, to get a sense for how much actual cooling is taking place, a benchmark might be necessary. That'd be a challenging benchmark to set up. Or you could just treat the system like I'm trading boiling water (from the hot tank) for hot water (from the geyser). But that'd neglect the heat in the oxygen. But that might be ok because the water has more heat capacity anyway.

[trukogre]

"10 million joules per second deleted"  Geyser water is generated at 97 C.  If you're deleting it at 95 C,  then in a certain sense you're actually creating heat with that part of that cycle.  your calculations are bogus anyway, you're using the specific heat of liquid water from 0 K to 273 K, even though water is not liquid at those temperatures, and the specific heat of ice in ONI is much lower.

 

So, the question is, if geysers generate water at 95 C, how are you able to dump the heat of 3 aquatuners into your hot water tank without boiling it?  There are a few possibilities.

1.  You're dissipating heat by not using abyssalite pipes and not enclosing your geysers in abyssalite, so you're just moving heat around from your base to the warm biomes far from your base. you mentioned using an abyssalite pipe, but perhaps your insulated tank is not abyssalite?

2.  You're using the CFA bug, probably unintentionally.

or some combination of the above.

Complaining about machine deletion when the CFA bug is orders of magnitude more powerful and more annoying seems misplaced.

21 hours ago, Saturnus said:

If you want to know how much the borg cube cools then it's 6000kg of petroleum and 2000kg of iron going from +70C to -40C in 11 seconds on normal slow speed. 

Hey saturnus.  I had a question about the CFA bug.  I noticed, again, that polluted water on top of normal water turns the normal water polluted, but normal water on top of polluted water seems to stay normal.  Do you think that's a separately programmed function, or connected to the CFA bug?

[avc15]

he is correct about the geyser making steam at 100C, and this wrecks the whole thing.

Mine was doing some work probably because my water rejected heat to the environment between when the geyser spat it out and when it arrived in the aqua tuners.

Still, I am disturbed by how everyone on this forum is so married to absolute pronouncements :b. Yes, physics is a set of hard and fast rules that don't change, but even the best design engineers overlook great ideas just by being unwilling to even discuss starting assumptions. Also ONI isn't physics ! (admittedly fluid mechanics isn't my profession, thank god, all those bernoulli curves drive me mad)

I did the work again in the following way. If you electrolyze water that isn't heated to 99 degrees, you could have deleted 4 kW more per electrolyzer per degree below 100C (looking at the water you used). Or, you unnecessarily heated your base by 4 kw per electrolyzer per degree below 100C of the input water. So, the idea of having a preheater cooling some other fluid before electrolyzing is still solid, especially since HVACs and aqua tuners behave in such a magical way.

So if my water was 90C before making it to the hot tank, in my 8-electrolyzer setup, heating back to 99C before electrolyzing would reject an extra ~300 kw. I was off by at least an order of magnitude, then, depending on what you're doing . But still, if you're electrolyzing anything significantly below boiling, you're retaining way more heat in your world and/or base than you need to.

And also still, I think that heat deletion is dumb. They should add conservation of energy to the game and leave the entropy device as the only thing that gets to break the rules.

[trukogre]

15 minutes ago, avc15 said:

Still, I am disturbed by how everyone on this forum is so married to absolute pronouncements

That is itself an absolute pronouncement   Most people are just speaking colloquially and not taking the time to write academically, because they're not getting paid or graded, and a few exceptions to the rule are into speaking absolutely.

 

15 minutes ago, avc15 said:

And also still, I think that heat deletion is dumb. They should add conservation of energy to the game and leave the entropy device as the only thing that gets to break the rules.

I wouldn't go that far.  What I will say is this: had I been the designer of ONI, then heat deletion would be accomplished by building radiators on the surface of the asteroid.  But I'm not, and I enjoy the game, so I try to take it on its own terms; if I want to make my own game, I should make my own game not criticize someone else's.  As I said before, the thermodynamic bugs in this game are much more powerful and unavoidable than heat deletion through machines, so I'm not sure why you're complaining about the latter while not mentioning the former.  Go run the math on Saturnus' Borg box, the cold it generates is hilariously OP, and it doesn't require all your renewable water to run either.

[avc15]

6 minutes ago, trukogre said:

That is itself an absolute pronouncement

 

aha, thanks for pointing that out! I really do try to avoid it. Speaking in terms of "that seems" or "shouldn't it" has lead me to more answers in my life than "it must be this particular thing". And the latter mindset has caused me to pass up plenty of opportunities. Being willing to question your own methods and even dissect the assumptions in ollllld physics will keep your conclusions honest.

[avc15]

but I came to a realization about colonies that use water from geysers to produce oxygen or food for many duplicants. Even if you're preheating water before electrolysis, the more geyser water you use the more new heat you're pumping into your asteroid. You can dele some of it (by electrolyzing boiling water) but you're introducing even more of it just by nature of letting the geyser continue to spit out more steam.

So really the heat balance is net positive, and a very large number, I think. You're just reducing the magnitude of that by preheating water before  using it.

I don't think this method can actually result in a net negative heat balance.You might use this method to move some of that heat away from your base, though, and contain it somewhere else.

[Zarquan]

I use natural gas generators to cool my base.  What I do is I take the runoff from the natural gas generators and run it over aquatuners.  I then use the hot polluted water to make fertilizer.  It also allows for directing where the cold ends up.  My base is (mostly) nice and cold because of it.  You could also probably cool the natural gas generators by immersing them in hydrogen and surrounding them with wheezeworts to make the initial polluted water colder (as it takes the heat of the natural gas generator) and thus allow for more thermoregulators.  This allows me to take the ~80 C water from my geyser (it wasn't always insulated) and easily cool it for no downside other than electric cost.  It is another decent approach to the problem.

[FIXBUGFIXBUGFIX]

12 hours ago, avc15 said:

So it's better to discuss why there are problems with notions of absolute heat, and see if there's a way to build a meaningful model anyway.

First of all, I appreciate your advice.

In real life, the molar heat capacity of H2 is 28.836 J/(mol·K), about 14J/(g·K), much bigger than 2.4J/(g·K) in game. It's hard to build a model without causing crazy temperature. 

11 hours ago, trukogre said:

Do you think that's a separately programmed function, or connected to the CFA bug?

 I guess the horizontal flow of water in pH2O tank causes the water polluted, an intended function, not sure.

 

EDIT: I do some experiment about water pollution.

It seems only happened when a tile of water is surrounded by at least 3 tiles of polluted water(right, left, top left).

Not happen when being surrounded by right&left&top-right or left&top-left

[BT_20]

So basically from what I've seen there are a lot of ways to delete but the most broken of them are fertilizer makers the vertical temp exploits.