[0.25]KSP Interstellar (Magnetic Nozzles, ISRU Revamp) Version 0.13

[Einarr]

I never actually used the Sethlans/Akula. I used the other 3.75m fission reactor to create several power stations before I developed Fusion, then used Microwave Thermal Receivers to run thermal rockets remotely (power and relay network in place, of course). I went with the molten salt reactors so I wouldn't have t service them as often.

Now that I have upgraded fusion, I don't really use the fission reactors at all, aside from perhaps a probe size one for backup power on manned flights (I also use TAC Life Support, and so need to keep EC onhand at all times).

Edited May 5, 2014 by Einarr

[WaveFunctionP]

@WaveFunctionP: Noted an inaccuracy in your reactors video. The Tier 2 (Sethlans, Sethlans 2, Akula) fission reactors are actually unlocked prior to Fusion Power. I know as I had them as options before I'd unlocked Fusion Power when I added KSPI to my mod list. Fission reactors get a core upgrade at Fusion Power allowing them to generate ~3x the power they could before, but still not on par with even unupgraded Fusion. A review of the relevant part configs and the tree config indicates that the Tier 2 fission reactors are unlocked at the same tech as the Tier 1 fission reactors, Nuclear Propulsion.

Shows how much I use them. They are part bloat as far as I am concerned. The basic fission reactors could have a UN mode if it were important to have that resource mode in the game. It isn't, as far as I can tell, so...yeah.

[smunisto]

I made my first and only so far power station using in Kerbin orbit using 4 unupgraded Akulas, as I was led to believe that even if they are more maintenance dependant - they produce more power somehow(no idea why I think like this).

Reading people's opinions I may have to rethink and actually use MSRs.

[Einarr]

The Particle Bed reactors do produce more power than MSRs, and are lighter. Unfortunately, they split some of their generated power between ChargedParticles and ThermalPower, making it more difficult to utilize. The major caveat at that tech level is that they take more maintenance. Once I got into Fusion, I decommissioned my power relay network (with fire) and all vessels that relied on it as FTRs (that's Fusion Thermal Rockets) became more useful to me

Trying to get a probe going for SCANSAT stuff as I don't want to have a crewed ship in some polar orbit for weeks on end mapping planet/moon/thing X and wishing for a probe sized AM reactor and tank...

Edited May 5, 2014 by Einarr
Squashing typos...

[WaveFunctionP]

The Sethlans and Akula reactors aren't of a higher tier than the original molten salt reactors, I don't really see one or the other as being better, just a bit different.

The MSRs are really focused on prolonged lifetime and ease of use while the others are a bit more complicated with the passive heat safety features and variable Isp performance of the engines.

I see the choice between them as a matter of preference, I'd be interested to get a feel for what other people prefer though.

I'm a geek. I have a background in physics and chemistry, but I still see no reason to include every variation of nuclear power production conceivable unless it add depth to the gameplay. Many things currently just add complexity. (Looking at you waste heat and generators) It adds parts, and complexity to the design process (or more correctly, adds to the learning curve), but I'm not convince than it adds much depth.

Which sounds like jargon, so let me explain. I can choose to build my rocket with a variety of engines. Each size has viable engines that have niches they are intended to fill. There are gaps between available parts, like where I need more ISP and less thrust or weight or less parts or whatever. (Square pegs to fill a round hole. It'll never be optimal, but you can get close intuitively.) Now whatever goal I have for my rocket's design, I have to design around these gaps to compensate for them. This is gameplay, an optimization problem, complex enough that it is difficulty to optimize fully, but not so complicated that I need to resort tools to help me parse the information.

Not so much with the way many things work in KSPI. Waste heat is a just a thing that makes you add parts to your ship. You figure out how many you need. The vast majority of the time, this means enough to put the numbers in the green in the VAB. Adding more or less radiators has little benefit, so there is little incentive to optimize. Radiators simply force the player to remove the waste heat penalty. The resource adds no functional gameplay.

Generators are also problematic. If you need power, add one(or two). Even the placement on the vessel is a forced requirement, as is the size of the generator, for all intents. The mode of the generator, has already been decided by the reactor you've already chosen. There is very little decision making in this process after you learn the mechanics. The only challenge was learning how they work, which was only a challenge because there was little player messaging in the mod to tell the player how they work.

Reactors. The long duration of fission reactors has little value given the duration of a typical save, and particularly, given the duration of the mission they are needed to accomplish. The EVA maintenance shenanigans and requirements for refueling and operating the reactors only make them more of an inconvenience. Since their duration is not really much of an advantage, their limitations (power to weight ratio, maintenance trickery) make them obsolete very quickly. They don't have a niche to fill. They are simply an inferior square. The PFission reactors have no niche as far as I can tell. None. Fusion is great, but the extra modes are useless. He-3 is so hard to get, even if did decay properly, that it isn't worth bothering with. And antimatter reactors, well, they break the game. But you are pretty much done with the save by the time you get them. The AIM reactor is useless.

And all that is before considering that usually there is very little reason to use a smaller reactor. So, in most circumstances, your reactor size is chosen for you.

Concerning KPSI, the design process goes something like this:

Use whatever number of the 3.75 fusion reactors you need to complete your mission either onboard the vessel or via network, if you need onboard power put a generator on the reactor to meet demands, and fit as many radiators as required.

[wooaa]

I have a few questions about what some of the resources are used for. What does nitrogen and hydrogen from the atmo scoop do?

[WaveFunctionP]

I have a few questions about what some of the resources are used for. What does nitrogen and hydrogen from the atmo scoop do?

Nitrogen is used to create ammonia. Hydrogen is liquid fuel.

You can see what various resources can be used for on the wiki.

The flow chart on the isru page may be particularly helpful.

https://github.com/FractalUK/KSPInterstellar/wiki/Isru-Refinery

[wooaa]

thanks a lot, that makes sense.

[undercoveryankee]

The Sethlans and Akula reactors aren't of a higher tier than the original molten salt reactors, I don't really see one or the other as being better, just a bit different.

The MSRs are really focused on prolonged lifetime and ease of use while the others are a bit more complicated with the passive heat safety features and variable Isp performance of the engines.

I see the choice between them as a matter of preference, I'd be interested to get a feel for what other people prefer though.

The Sethlans/Akula series are lighter than fully fueled green reactors. When I'm trying to use unupgraded fission reactors on thermal rockets, the lighter weight helps with maneuverability and TWR.

Feature request: allow FNNozzleController to search for an FNReactor module on the same part. The LV-N feels a little cheaty alongside the similar-tech fissions, and I'd still like to be able to convert it to Interstellar's modules.

[Deredere]

I'm a geek. I have a background in physics and chemistry, but I still see no reason to include every variation of nuclear power production conceivable unless it add depth to the gameplay. Many things currently just add complexity. (Looking at you waste heat and generators) It adds parts, and complexity to the design process (or more correctly, adds to the learning curve), but I'm not convince than it adds much depth.

Which sounds like jargon, so let me explain. I can choose to build my rocket with a variety of engines. Each size has viable engines that have niches they are intended to fill. There are gaps between available parts, like where I need more ISP and less thrust or weight or less parts or whatever. (Square pegs to fill a round hole. It'll never be optimal, but you can get close intuitively.) Now whatever goal I have for my rocket's design, I have to design around these gaps to compensate for them. This is gameplay, an optimization problem, complex enough that it is difficulty to optimize fully, but not so complicated that I need to resort tools to help me parse the information.

Not so much with the way many things work in KSPI. Waste heat is a just a thing that makes you add parts to your ship. You figure out how many you need. The vast majority of the time, this means enough to put the numbers in the green in the VAB. Adding more or less radiators has little benefit, so there is little incentive to optimize. Radiators simply force the player to remove the waste heat penalty. The resource adds no functional gameplay.

Generators are also problematic. If you need power, add one(or two). Even the placement on the vessel is a forced requirement, as is the size of the generator, for all intents. The mode of the generator, has already been decided by the reactor you've already chosen. There is very little decision making in this process after you learn the mechanics. The only challenge was learning how they work, which was only a challenge because there was little player messaging in the mod to tell the player how they work.

Reactors. The long duration of fission reactors has little value given the duration of a typical save, and particularly, given the duration of the mission they are needed to accomplish. The EVA maintenance shenanigans and requirements for refueling and operating the reactors only make them more of an inconvenience. Since their duration is not really much of an advantage, their limitations (power to weight ratio, maintenance trickery) make them obsolete very quickly. They don't have a niche to fill. They are simply an inferior square. The PFission reactors have no niche as far as I can tell. None. Fusion is great, but the extra modes are useless. He-3 is so hard to get, even if did decay properly, that it isn't worth bothering with. And antimatter reactors, well, they break the game. But you are pretty much done with the save by the time you get them. The AIM reactor is useless.

And all that is before considering that usually there is very little reason to use a smaller reactor. So, in most circumstances, your reactor size is chosen for you.

Concerning KPSI, the design process goes something like this:

Use whatever number of the 3.75 fusion reactors you need to complete your mission either onboard the vessel or via network, if you need onboard power put a generator on the reactor to meet demands, and fit as many radiators as required.

I'm not saying this guy is right, but this guy is right. I'm pretty sure I less eloquently said the same a few months back.

I like radiators, however. They look cool.

[wooaa]

Does the refinery still collect resources if it is not the active vessel?

[bonesbro]

Reactors. The long duration of fission reactors has little value given the duration of a typical save, and particularly, given the duration of the mission they are needed to accomplish. The EVA maintenance shenanigans and requirements for refueling and operating the reactors only make them more of an inconvenience. Since their duration is not really much of an advantage, their limitations (power to weight ratio, maintenance trickery) make them obsolete very quickly. They don't have a niche to fill. They are simply an inferior square. The PFission reactors have no niche as far as I can tell. None. Fusion is great, but the extra modes are useless. He-3 is so hard to get, even if did decay properly, that it isn't worth bothering with. And antimatter reactors, well, they break the game. But you are pretty much done with the save by the time you get them. The AIM reactor is useless.

I largely agree, though I think that long duration of fission reactors is a big plus for building bases. I've sent bases and orbital labs to other planets, then did a couple of missions to Jool. Those are multi-year missions, and it was very frustrating to finish those and realize that a lot of the bases and power satellites I'd built were junk after running out of fissionables.

Completely agree on He-3 and the AIM reactor. I tried building an He-3 miner this weekend. Separate post.

[bonesbro]

So this weekend I tried He-3 mining. First I built a simple Fusion SSTO with a small radial scoop and dove it into Jool at 40k, then left it scooping while I took a shower and worked a bit. In one hour it mined, uh, something like 0.05 He-3.

So I built a second SSTO. Two fusion thermal turbojets and six large scoops. I dove it deep to 4k and ran it. It mined one unit of He-3 in 190 seconds. To get a full reactor's worth of (1000 units) He-3 would have taken 52.78 hours. Real human hours, because you can't do atmospheric flight under time acceleration. (Even if the plane was stable at 4x physics warp, that's still 13 hours).

And, having invested that time, my returns would have been very low. I could have used it to generate about 27% more power from a fusion reactor for one kerbal year. That would never, ever be worth it: very little would require that extra power, and if I did need the extra power I would be much better served by either adding another reactor (for a heavier vehicle with minimal extra time) or by setting up a microwave power network (which would benefit me for a very long time, not just for this one ship). So, with the current He-3 resource constraints, I conclude that He-3 fusion is useless.

The only other thing it would allow is used of the AIM reactor. The AIM has a fantastic power/weight ratio - far better than fusion, but still worse than antimatter. However, its raw power generation is actually still lower than pure fusion reactors, and you have to manage creation and storage of antimatter. Ignoring He-3 availability, Fusion is better from a convenience standpoint and from a raw power standpoint, and antimatter is way ahead in both regards.

Now it is interesting to consider the gameplay options that open up if He-3 was available in the VAB. You would have an actual choice to make with your fusion reactors: you could eliminate their utility as a thermal rocket to gain higher electrical production. That's an interesting design choice to make, and the optimal choice changes based on how you design your craft. That seems like a well-balanced gameplay option, one that requires no additional code and gives the player more options. It also opens up the AIM reactor as a viable choice for some ship designs. It requires the player to manage acquisition/production of antimatter, and produces less electricity than a fusion reactor, but it will be excellent in some designs because of its superior power/weight ratio. There's the lore question of where the He-3 is coming from, but we're talking about a society that is building antimatter reactors and preparing to build a frickin' warp drive. Maybe they figured out how to make He-3 in a particle accelerator or found a fission chain that leads to abundant He-3 byproduct. It doesn't really matter how - I think we can just abstract away that part of their industry and say they've figured out how to make it work.

Should probably make it mineable somewhere in usable quantities, so here are my suggestions:

1. He-3 can be filled and tweaked from the VAB
   
2. He-3 can be mind from the Mun (in low quantities) and from, uh, how about Dres, Tylo, Moho, and Eeloo (so there's some challenge)
   
3. He-3 harvesting rates increased by a factor of 1000 in Jool. Possibly just below, say, 10k, as, uh, the miner hits an He-3 layer or something.
   

[artforz]

*warning, contains sarcasm*

"Waste heat is a just a thing that makes you add parts to your ship." ... unlike ElectricCharge?

I mean, if vessels can magically dissipate a few gigawatts of heat, they might as well magically produce a few kilowatts of electricity.

Also, which radiators you use and where they're placed doesn't affect your Cm and aerodynamics at all, right?

Generators: if I just want to run a big thermal nozzle or jet, I don't *need* the extra mass of a big generator. Depending on what reactor I'm using I might not need any generator, or maybe a kiwi + 1.25 gen somewhere on the vessel is enough to run the plasma heating on that 3.75 fusion gen... "hmm, let me check the numbers on that". Yeah, clearly no consideration involved at all. And I guess where to put that APU is "a forced requirement", too. Right?

Reactors: Somewhat agreed. A fully fueled fission reactor lasts a loooong time. Unless you're building bases and/or letting years pass just for fun, they seem rather overfueled.

As for the AIM, if that thing didn't require bloody He3 it'd be actually rather useful, a basic AIM has power/weight rivaling upgraded fusion (!) and the upgraded AIM is up there with AM reactors.

As for "always go for 3.75 fusion"... currently that's a pretty good bet, assuming you have unlocked it and assuming there will never be such a thing as a "budget"...

Hmm, re-reading this post up to this point, the tone ended up quite a bit more confrontational than intended. Too lazy to re-write it in a more diplomatic tone, just consider it a character flaw or something.

In closing... Well, I guess there's quite a few legitimate balancing issues. Anything involving He3 is too painful to use. Particle bed reactors' better TWR is non-obvious. Beamed power is way too easy when you can throw a dozen 3.75m reactors into orbit for free and active microwave power receivers don't snap off going mach 7. Lots of the ISRU stuff seems to fall into the "pointless stuff to waste time with once you unlock everything" category. not sure where I'm going here, guess I should just stop rambling.

[phoenix_ca]

Does the refinery still collect resources if it is not the active vessel?

IIRC, no, it doesn't. Edit: That said I could be wrong. There are some things KSPI does in the background and some, very similar things, that it doesn't, like Tritium-to-He3 conversion. The wiki has no info on whether or not ISRU collection can work on a ship that is out-of-focus.

@bonesbro: Agreed with your entire post. He-3 collection is just depressingly grindy and painful. Realism be damned. Your ideas for it being a mined resource on certain moons/planets is a pretty great one. He-3 mining is actually a possibility for our own moon, come to think of it. It's far, far, far, far, far from practical at the moment, but who knows, maybe in the future. We need a way of getting large payloads to the moon and back that's way less costly. Maybe a space elevator would fix the issue. ... Okay, I'm on a wild tangent now.

IIRC, at some point, Fractal or WaveFunction made mention of it being possible to simply make the parts tweakable, like He-3 and AM tanks. Someone asked about it a few pages back. So it should be possible to make He-3 available in the VAB. Part of the issue there is that career mode is far from done, so the ability to balance that ability with high cost per unit isn't here yet. (He-3 in reality is a spectacularly rare resource. We're actually having serious problems keeping-up with global supply. Not that realism should rule KSP. Ever.)

As for harvesting rates on Jool, I think you might have some options there. The atmospheric scoops use the following module:

MODULE
{
	name = ISRUScoop
	scoopair = 0.6
}

Increasing the scoopair value would probably increase collection rates quite a bit. The downside is that it would impact them globally for all resources, so common things like oxygen and nitrogen might fill instantaneously.

The other, probably far better option, is to adjust the values in /GameData/OpenResourceSystem/PlanetResourceData/atmosphericresourcedefinitions.cfg . See this section:

{
	name = JoolHelium3
	guiName = Helium-3
	celestialBodyName = Jool
	abundance = 0.00000137
}

The important bit should be obvious, abundance. Increase that number to be in line with deuterium at 0.00003, or perhaps just a smidge below, or increase both. I'd go for both to cut-down on collection times across the board.

For mining on planets, you could go the easy route, create a small PNG pure white (well, probably not for balance), add that to Open Resources, define it in /GameData/WarpPlugin%-somethingIcan'trememberrightnow%, and ta-da. Done. Alternately, create your own greyscale maps with say, Gimp.

Edited May 6, 2014 by phoenix_ca

[ABZB]

Wait a second, a wild solution appeared!:

The Fusion reactions should have byproducts!

From Wikipedia:

[A] D + D → He3 + n + 3.268 MeV

D + D → T + H-1 [p (protium)] ('Normal' Hydrogen, this could be treated as LiquidFuel, assuming it is being treated as H2 (ok, so you need some electrons) + 4.032 MeV

D + T → He4 (not useful for fusion, but is needed for that telescope cooling, so convenient source for the Gravitational Lense mission) + n + 17.571 MeV

So:

D-D Fusion produces Tritium, which is useful for D-T reactions, as well as for decay into He-3. It also produces some amount of He-3 directly. It also provides [some, did not do the math, presumably relatively small output compared to needs of most engines] of LiquidFuel which IS useful for the plasma thrusters, given their high ISP. It supplies noticeably less power. The ratio of occurrence of reaction [A] to is 1:1.

D-T Fusion supplies the most power, but the products are not useful unless you are running a telescope.

http://en.wikipedia.org/wiki/Fusion_power#Possible_Approaches

D-He3 yields He-4 and H-1 (Helium Coolant and LiquidFuel)

He3-He3 yields He-4 and 2 H-1 (ditto) it also yields about 2/3 the energy of D-He3

[bonesbro]

Wait a second, a wild solution appeared!:

The Fusion reactions should have byproducts!

From Wikipedia:

[A] D + D → He3 + n + 3.268 MeV

D + D → T + H-1 [p (protium)] ('Normal' Hydrogen, this could be treated as LiquidFuel, assuming it is being treated as H2 (ok, so you need some electrons) + 4.032 MeV

D + T → He4 (not useful for fusion, but is needed for that telescope cooling, so convenient source for the Gravitational Lense mission) + n + 17.571 MeV

So:

D-D Fusion produces Tritium, which is useful for D-T reactions, as well as for decay into He-3. It also produces some amount of He-3 directly. It also provides [some, did not do the math, presumably relatively small output compared to needs of most engines] of LiquidFuel which IS useful for the plasma thrusters, given their high ISP. It supplies noticeably less power. The ratio of occurrence of reaction [A] to is 1:1.

D-T Fusion supplies the most power, but the products are not useful unless you are running a telescope.

http://en.wikipedia.org/wiki/Fusion_power#Possible_Approaches

D-He3 yields He-4 and H-1 (Helium Coolant and LiquidFuel)

He3-He3 yields He-4 and 2 H-1 (ditto) it also yields about 2/3 the energy of D-He3

Nice find. That would be handy to do in space, similar to the way we only carry a small amount of tritium and breed the rest from lithium.

If the kerbals can breed He3 at will in their on-planet fusion reactors, they could provide a supply of He3 directly to the space program. If players have to breed it themselves, they'll just build a pile of 20 reactors on it and breed it on the runway, then dump it into a truck. Same result, just with more micro.

[Atrius129]

Nice find. That would be handy to do in space, similar to the way we only carry a small amount of tritium and breed the rest from lithium.

If the kerbals can breed He3 at will in their on-planet fusion reactors, they could provide a supply of He3 directly to the space program. If players have to breed it themselves, they'll just build a pile of 20 reactors on it and breed it on the runway, then dump it into a truck. Same result, just with more micro.

On this note, would it make sense just for Trit/He3 and maybe AM tank tweakablilty be unlocked via tech upgrade? Say Kerbal society figures out how to manufacture them when they unlock AM technology(or whatever)?

I'm still really hoping somebody will figure out how to collect resources for a usable pool in the VAB. At least for AM. That would be the bees knees.

[WaveFunctionP]

*warning, contains sarcasm*

"Waste heat is a just a thing that makes you add parts to your ship." ... unlike ElectricCharge?

I mean, if vessels can magically dissipate a few gigawatts of heat, they might as well magically produce a few kilowatts of electricity.

Also, which radiators you use and where they're placed doesn't affect your Cm and aerodynamics at all, right?

Generators: if I just want to run a big thermal nozzle or jet, I don't *need* the extra mass of a big generator. Depending on what reactor I'm using I might not need any generator, or maybe a kiwi + 1.25 gen somewhere on the vessel is enough to run the plasma heating on that 3.75 fusion gen... "hmm, let me check the numbers on that". Yeah, clearly no consideration involved at all. And I guess where to put that APU is "a forced requirement", too. Right?

Reactors: Somewhat agreed. A fully fueled fission reactor lasts a loooong time. Unless you're building bases and/or letting years pass just for fun, they seem rather overfueled.

As for the AIM, if that thing didn't require bloody He3 it'd be actually rather useful, a basic AIM has power/weight rivaling upgraded fusion (!) and the upgraded AIM is up there with AM reactors.

As for "always go for 3.75 fusion"... currently that's a pretty good bet, assuming you have unlocked it and assuming there will never be such a thing as a "budget"...

Hmm, re-reading this post up to this point, the tone ended up quite a bit more confrontational than intended. Too lazy to re-write it in a more diplomatic tone, just consider it a character flaw or something.

In closing... Well, I guess there's quite a few legitimate balancing issues. Anything involving He3 is too painful to use. Particle bed reactors' better TWR is non-obvious. Beamed power is way too easy when you can throw a dozen 3.75m reactors into orbit for free and active microwave power receivers don't snap off going mach 7. Lots of the ISRU stuff seems to fall into the "pointless stuff to waste time with once you unlock everything" category. not sure where I'm going here, guess I should just stop rambling.

What I meant by my statement about waste heat is that it doesn't create very interesting limitations. The number of radiators you use is pretty much determined by the equipment you've already selected to use. The aerodynamics aren't much of a factor unless you are using FAR, and even then if you are using thermal nozzles/jets you don't have to worry about it much. In that configuration, most of your power demand and thus waste heat production is both created and consumed by the nozzle during operation. You also have the option of using the atmospheric radiators for that duty as well. COM issues will be present with or without the radiators.

I'll contrast that with payloads. Payloads on the face of it simply means that you need to fulfil a requirement (the dv for your mission), so you design a launcher to do the job. However, you have a wide variety of options to choose from to complete that goal. Lots of interesting decisions about staging and part selection and placement. Keep in mind, this is a contrast, not an analogy to waste heat management.

With waste heat, you simply put whatever number is needed. The only real consideration is where you are going to place them and like any part, how much it will effect DV. It's not as deep. Stating that EC isn't any more interesting than waste heat doesn't somehow justify that we need to have another system equally as uninteresting. And to be frank, EC management at least has the fortune of being straightforward to understand.

The limitations of generators to be placed directly to the reactor, while more realistic, basically removes a design choice. A similar thing can be said about the penalty to mismatched sizes. Maybe I don't need a lot of power generation, but I need some. Well, I have to place another small reactor somewhere else on the vessel and place a generator on that reactor. The generator limitations aren't making that an interesting decision (the power requirement is doing that itself), they reducing the possibly space. If you add a requirement, you want it to change the possibility space, not reduce it. True, games are about arbitrary rules, but removing possibility is something you want to try an avoid in a game. Removing the ability to throw the ball in american football doesn't make the game more interesting, however limiting the conditions of when and where the ball can be thrown does. Just as requiring a generator to be placed directly on a reactor removes possibilities, whereas having placement of the generator on the ship effect max power generation, thermal or particle efficiency or reactor temperature would be much more interesting by changing or even increasing those possibilities. The point is that a gameplay element should be interesting in this particular fashion or it should be removed unless absolutely required to make the gamespace small enough to be understandable and therefore, playable.

Don't worry, I didn't take your tone offensively, as I hope you do not for mine. Tone can be a very subjective and hard thing to express. I learned to mindful of that fact about it on the forums I frequent.

[Aedile]

It depends on your gameplay

Umm, radiators are pretty heavy, and without the heat mechanic plasma jets would be pretty crazy, there is FAR, and of course plasma jets and microwave power.

As far as reactors go, I don't consider nuclear reactors disposable, so I don't think there has been a single time I let nuclear reactor crash anywhere else than Jool (reactor graveyard)

Upgraded fission, is around as heavy as ungraded fusion (since you need two generators to get all the power), you have spot for thermal nozzle.

Antimatter initiated reactor weighs only 12 tons, uses relatively small amount of AM (it's upgraded version provides more power than a 2.5 unupgraded AM reactor, it's 4 tons lighter and uses fraction of the am. Compared with fusion, it provides almost the same power for 1/3 of the weight);

Anyway, imo fission is intended for some particular purpose. You can run it very long time, and with use of refinery/lab and a spent fuel container you can run it at full power, for very long time. The biggest hindrance however is that you need kerbal to perform maintenance, and you need to run it at 30% constantly, or wait for cool-down. So becomes pretty useless for networks, as say generator around Eeloo. It does not matter that you can use the fission much longer, because you can turn on and off a fusion one at will, and turn it on only when you need it.

Only time I'd think of using fission, is powering AM collection station, in far place where you don't have easy access to fusion fuel.

The akula type of fission, doesn't have the actinides issues, it's lighter, and the upgraded version creates a good amount of charged particles. It has it's own benefits.

[KvickFlygarn87]

How many MW would a 1.25m Fusion reactor (pure He3) generate in combo with a 3.75m generator at full efficiency?

DISREGARD.

Edited May 6, 2014 by KvickFlygarn87

[xfrankie]

A lot of people seem to forget, that even if He-3 would be available in the VAB, the only place where it is useful is the Antimatter Initiated Reactor. And for that you also need Antimatter... (By that point, why not use the antimatter itself in a way lighter 1.25 reactor?)

"Why do you think so?"

Well, if you try to pump He-3 into 3.75m Fusion reactor instead of Deu-Trit, its power output suddenly drops from 55GW (11 of which are charged particles) to about 2.4GW (yes, two gigawatts)... So even with ChargedParticles generator, it's still better to use D-T... (proof at the bottom)

He-3 in Tokamak reactors = useless.

"But you're forgetting InertialFusion!"

Yes, 1.25 and 0.625m Fusion reactors maintain their full power potential even in pure He-3 mode, producing all power in CParticles... But then they cannot be used for thermal nozzles and you still need at least six of them to power a Vista. And I can't imagine where else you would need to have all power produced in CP. As in, in which scenario are you going to need more than 300MW (D-T) but less than 450MW (pure He-3)? If you're going to use it as a power source for a probe, the D-T mode should still be an absolute overkill.

He-3 in Laser-confined reactors = sort of viable, saving a little bit of weight, at the cost of heavily (6x) increased part count and a really awkward ship design.

IMO, the biggest downfall of He-3 is the power drop in Tokamaks. Disregarding realism (in which it surely makes sense), I would expect that if Kerbals are able to harness Antimatter, they would have also figured out how to prevent the reactors from dropping to 4.3% of their max power.

I would suggest removing (or significantly reducing) the power drop in upgraded fusion (while keeping more power needed to heat the plasma), because the resource itself is extremely difficult to get (more difficult than AM), and if you're not willing to let mechjeb fly your vessel through Jool's atmosphere for several hours, you're not going to get much. And when you finally get some of it, it shouldn't be pretty much useless, as it is right now... 0.7GW of usable power out of 60ton reactor sounds more like a giant RTG than fusion

... rant over, have some pics

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Edited May 6, 2014 by xfrankie
I can't spell...

[Deredere]

6x laser fusions running a vista is precisely what I used He-3 for. Novapunch has some awesome 3.75m-7x 1.25m adapters that are perfect for the task. Makes a cool-looking and practical engine assembly.

And it's not bad, I guess.

But then you learn that thermal microwave receivers with a developed microwave network (probably running on D-T) hooked up to a generator can produce a literal hundred times the power with no waste heat and that idea is super out.

[philotical]

I was planning once to mine He-3 with the Hooliganlabs airships at Jool. - never did so far though

iirc you can set them to make slow to save - than you could leave the ship there..

But I'm not even sure if the scoops work while on rail - I guess not..

but if they where allowed to scoop on rails, that could be a viable way to gather He-3 in larger quantities..

I mean - beside the fact of it's minor usefullness lol

[bonesbro]

It depends on your gameplay

Umm, radiators are pretty heavy, and without the heat mechanic plasma jets would be pretty crazy, there is FAR, and of course plasma jets and microwave power.

I agree with Aedile about radiators - they're not deeply interesting on ships with their own reactors but they're very important for balancing microwave power. And it becomes a bit more of a balancing act trying to juggle radiators vs. convectors for SSTOs. I think it's a way more interesting mechanic than, say, TAC Life Support, which is just "add this extra mass or your kerbals die". Biggest problem is how hot upgraded radiators are allowed to get, which eliminates some of the design tradeoffs you have to consider on your early fission craft. (Core temperature vs. radiator temperature vs. generator efficiency).