[1.12.5] Supplementary Electric Engines

[NiL]

On 8/9/2023 at 1:57 AM, triple cheeseburger said:

Also, question; would you prefer if I released the resistojets and fuel tanks as an update and then released the arcjets once they're done later on as their own update? Or should I just stick with the plan of releasing all these parts in one major update?

I personally think it's better to release resistojets and tanks as an update. Those little things look so cute!

[triple cheeseburger]

7 hours ago, NiL said:

I personally think it's better to release resistojets and tanks as an update. Those little things look so cute!

Alright, once I finish the fuel tanks I'll release them and the resistojets as an update. Arcjets can then come in the update after that. Apologies for it taking awhile, I've been working on other stuff (some of which is KSP modding related) at the moment but I should have the time to get back to this soon

[Ameoba]

i didnt know this existed... well, time to abuse this

[InfoTheGamer]

On 7/19/2023 at 10:56 AM, triple cheeseburger said:

Awesome suggestions!

From what I've read arcjets have very different performance from resistojets, I was thinking to have them be a separate part. Could be unlocked slightly later in the tech tree or something, I feel like if they were unlocked at the same time then it would render the resistojets even more useless. And yeah I agree, if I were to include water as a fuel option I would go and add a few small water tanks. With liquid fuel I was thinking of people who don't have stuff like cryofuels installed and thus wouldn't be able to use things like liquid hydrogen. Though I suppose if the engines can use water and the mod includes water tanks then that eliminates the need for a liquid fuel option.

Cold gas thrusters are a neat suggestion, I was thinking about them a bit. Though they don't really fit the namesake of the mod (since they're not electric)... but I suppose I can make an exception (or rename the entire mod lol). Using liquid oxygen as a propellant is a cool idea - could maybe add it as a propellant option for resisto/arcjets too. Not sure about the tweakable thrust mode for CG thruster - can't really think of many use cases where it could come in handy and might just overcomplicate things.

So so far my current ideas for parts are something like this:

Cold gas thruster - has an engine and RCS version. Small and extremely cheap, but pitiful ISP. Propellant options include:

• Liquid oxygen (default option probably)
• Liquid hydrogen (slightly higher performance, but comes with the downsides of dealing with LH2)
• Liquid methane (sure why not)
• Water (although I suppose if liquid oxygen is available then it makes water a little bit useless, because liquid oxygen on its own is quite cheap - which is sort of what I was thinking with this option. Plus having some fuel tanks specifically for one mode of operation for an engine seems a bit weird so idk actually)

Resistojet - Similar to cold gas, but has slightly improved performance. Takes a small amount of electric charge. Can also use all the same propellants as the cold gas thruster can. Still comes in both engine and RCS forms.

Arcjet - An improved version of resistojets that is unlocked later on in the tech tree. Has a good ISP (around 2,000 seconds probably) and retains the multi-fuel options of its predecessors. Could maybe have RCS versions too?

I have not heard of monoprop ion engines, so I suppose I'll need to look into them a bit. If they look interesting though and could fill a niche I don't mind considering adding them to the mod.

Ooh, I know an Atomic Rockets screenshot when I see one.

If you're still working on this mod, I'd love to see if I can write an RO patch. Something that is always missing from RO is more options for advanced electric engines, especially resistojet and arcjet thrusters. Maybe even microwave electrothermal thrusters too. Nice work on the models/Waterfall patch!

[EnderiumSmith]

I have an idea for an electric engine: railguns. It would fire USI metals as propellant or maybe even solid oxygen pellets since theyre magnetic. Since its firing macroscopic solids the propellant is irrelevant to the isp. The universal containers have very bad dry mass ratio so a custom tank would be needed wheather they need special pellets or not. It would start at 700s isp but could be made longer like the fresnel from fft at the cost of increasingly prodigious amounts of electricity consumption.  The plume could look something like the pulses on the antimatter catalyzed microfusion engine where theres a brief streak of red. If used in the oxygen pellet mode it would be green, fading to red at the ends. i dont know what color iron would be. This engine could be useful in places with low volatiles like metallic asteroids or sunblasted planets where hydrogen for propellant isnt available. It could use the same engine chargeup mechanic as the lithium fusion engine where it has to keep going to remain on. I suspect it would be more efficient than other electric engine since its not wasting energy turning the propellant into plasma and fires all of it directly behind.

[triple cheeseburger]

Hello again everyone... recently I have been in the mood to play KSP again, and I decided I'd see if I can actually finish this mod. So I've been hard at work and have made some new thingamabobs for people to play with.

Supplementary Electric Engines v1.1 is out! You can download it here

I retextured and remodelled the Pulsed Plasma Thrusters, now they are closer in line to the proper Nertea artstyle. I also went and remade the resistojets for the third time, since the previous models were really quite bland. The resistojets run on monopropellant and have an Isp around 400 seconds, I also made an RCS version... I still have a few more engines planned, my list currently includes the arcjets and a FEEP (field-emission electric propulsion) thruster. All the stats are figured out, all that's left is to actually make the things. So hopefully that does not take too long... apologies this took awhile, I was doing other non-ksp projects. I hope you can enjoy! Feel free to post any cool screenshots you take with the engines, and give feedback if you have any.

Edited February 1 by triple cheeseburger

[Pxtseryu]

this will drastically affect the cubesat economy 

[The Dressian Exploder]

YOOOO THAT'S AWESOME!

[Manul]

On 2/2/2024 at 1:21 AM, Pxtseryu said:

this will drastically affect the cubesat economy 

cube-what? I use them to make low gravity personal transport aka flying chairs

P.S. by "low gravity" I mean that type of gravity when you can run into orbit or jump into escape trajectory, warranty void if used on the Mun.

Edited February 3 by Manul

[triple cheeseburger]

Progress update

Hello! I've been working on the Field-Emission Electric Propulsion (FEEP) thruster and its fuel tanks recently. This engine uses liquid caesium as a propellant, has an Isp of 10,200 seconds, produces 0.8 kN of thrust, and takes in 40 ec/s.

The engine has a beautiful green plume (disclaimer: I don't actually know what colour plume you'd get with caesium, I think it would be blue/cyan, but I'm not entirely sure. I've always wanted more engines with green plumes in KSP, and green is way more unique than cyan with this sort of stuff so green it is. Perhaps the propellant contains some amount of some other chemical that turns it green, who knows). The (relatively) low power cost and high Isp can make this engine attractive for situations where you need lots of delta-v, but the thrust is somewhat lacking. More importantly, caesium is very pricy - even more so than xenon. So you'll have to be careful with its use if you're in career mode (caesium is also extremely reactive and explodes violently when it comes into contact with water, but that's for the Kerbals to worry about).  Oh also, the actual caesium resource is a part of the mod - you won't have to download community resource pack or anything for this to work.

Next on the list is the arcjets (a 0.625m engine and a 1.25m engine, and a set of RCS thrusters). Once those are done I'll release them and the FEEP stuff as an update.

Thank you for your time.

[Skyliumc258]

the new engines are cool, probably are the first ones with green plumes

[EnderiumSmith]

Caesium has a bluish purple emission, the next element barium would actually be green so i guess it fits:

 

[funnelton]

On 2/5/2024 at 7:45 PM, triple cheeseburger said:

Progress update

Hello! I've been working on the Field-Emission Electric Propulsion (FEEP) thruster and its fuel tanks recently. This engine uses liquid caesium as a propellant, has an Isp of 10,200 seconds, produces 0.8 kN of thrust, and takes in 40 ec/s.

The engine has a beautiful green plume (disclaimer: I don't actually know what colour plume you'd get with caesium, I think it would be blue/cyan, but I'm not entirely sure. I've always wanted more engines with green plumes in KSP, and green is way more unique than cyan with this sort of stuff so green it is. Perhaps the propellant contains some amount of some other chemical that turns it green, who knows). The (relatively) low power cost and high Isp can make this engine attractive for situations where you need lots of delta-v, but the thrust is somewhat lacking. More importantly, caesium is very pricy - even more so than xenon. So you'll have to be careful with its use if you're in career mode (caesium is also extremely reactive and explodes violently when it comes into contact with water, but that's for the Kerbals to worry about).  Oh also, the actual caesium resource is a part of the mod - you won't have to download community resource pack or anything for this to work.

Next on the list is the arcjets (a 0.625m engine and a 1.25m engine, and a set of RCS thrusters). Once those are done I'll release them and the FEEP stuff as an update.

Thank you for your time.

ohhhhh theyre beautiful.... 
 

[triple cheeseburger]

Alright just a quick progress update, after some feedback I decided to change the propellant choice for the FEEP thruster to Indium instead of Caesium. Also updated the plume colour to something hopefully more accurate.

[Thatguywholikesionengines]

loved the green plume, alas... I NEEEEEEEEED IT. i'm gonna use some of these on crewed ships and by god will it be cursed

[EnderiumSmith]

So what would be the use case for FEEP over the HISNAP and under driving it? the tiny nuclear reactor makes 60kW so xenon would make more thrust there. It looks light so maybe for missions where power is really low it would save weight? Maybe since it uses very dense liquid metal it could get better mass fractions? The resistorjets seem to not be any better than ants due to lower mass fractions and xenon has it even lower.

edit: but if the mass fraction would be made better we would run into the same issue but with why pick xenon over clusters of these. NFP itself runs into the same issue: why would i ever pick the DAWN after unlocking the NEXT?

Also i think the old PPT texture looked better.

Edited February 10 by EnderiumSmith

[triple cheeseburger]

Hello once again... Unfortunately I have gotten a bit burnt out on KSP modding for now, so it might be awhile until I get back to this. However...

Supplementary Electric Engines v1.2 is out!

This new update includes the FEEP thruster, its fuel tanks, and some minor tweaks here and there. Since these were already finished I figured I'd release them as an update. Still not 100% sure about the balancing with these, so any feedback is welcome. The FEEP thruster and its fuel tanks also include support for Community Tech Tree.

[Manul]

Here are some crafts I've built using this mod

This one looks military but it's totally harmless

.... or not so harmless

Spoiler

Still have no fancy name for this ugly creature:

Spoiler

 

[Iapetus7342]

electric engine go BZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

[newvegasmatt]

On 2/14/2024 at 2:23 PM, triple cheeseburger said:

Hello once again... Unfortunately I have gotten a bit burnt out on KSP modding for now, so it might be awhile until I get back to this. However...

Supplementary Electric Engines v1.2 is out!

This new update includes the FEEP thruster, its fuel tanks, and some minor tweaks here and there. Since these were already finished I figured I'd release them as an update. Still not 100% sure about the balancing with these, so any feedback is welcome. The FEEP thruster and its fuel tanks also include support for Community Tech Tree.

@triple cheeseburger

I just came across this mod, and I have to say that I absolutely LOVE it!

 

From a gap filling stance, it is almost perfect, more on that in a second. I noticed in previous posts that you asked for feedback.

I do have some, and pretty much all of it is very easy to fix.

 

My biggest suggestions are balance, use case, and compatibility.  (In addition to finishing the Arcjets!!! Those sound awesome!)

I apologize in advance for how long and wordy this will be, I will admit I had a little fun with this. Note, that all of the numbers I have listed as suggested changes, I have been using in my own game (with the exception of the Caesium) and love the position of the engines with these new numbers.

 

EDIT: I changed a few numbers after further testing. I will make what was editted.

 

Balance: 

This is the biggest issue, but is also the easiest to fix luckily. This all revolves around cost.

In a nutshell, most of these engines are WAY too cheap. Like an order of magnitude too cheap. (though the FEEP is pretty good)

I'm going to go deep into the weeds and analysis the cost of each engine, its propellant, and similar engines in stock, RLA, and NFP.

I'll use the config names for the engines for ease of locating the files and numbers. (sorry not sorry for the below info dump)

Note: I will use the chart below to reference the use case section as well as the cost balance section:

          PPT_22: 50 funds, 0.04 mass, 0.48 thrust, 1370 isp, 341.765 EC, solid fuel

          PPT_33: 112.5 funds, 0.09 mass, 1.08 thrust, 1370 isp, 341.765 EC, solid fuel

          rj_engine_big: 90 funds, 0.07 mass, 1.5 thrust, 415 isp, 1 EC, monoprop (2.8 EC/s)

          rj_engine_small: 15 funds, 0.015 mass, 0.3 thrust, 395 isp, 1 EC, monoprop (0.8 EC/s)

          SEE_FEEP_engine: 5500 funds, 0.15 mass, 0.8 thrust, 10200 isp, 1 EC, liquidindium (see last section) (40 EC/s)

          SEE_rj_rcs: 18 funds, 0.013 mass, 0.1 thrust, 365 isp, 1 EC, monoprop (0.4 EC/s)

Now for comparable engines:

          STOCK- ionengine: 8000 funds, 0.25 mass, 2 thrust, 4200 isp, 18 EC, Xenon (8.74 EC/s)

          NFP- ionXenon: 3910 funds, 0.2 mass, 2.1 thrust, 6380 isp, 178.758 EC, Xenon

          NFP- ionArgon: 1950 funds, 0.1 mass, 1.5 thrust, 2200 thrust, 0.257 EC, Argon

          NFP- mpdt_0625: 9230 funds, 0.33 mass, 47.3 thrust, 2600 isp, 115.139 EC, Lithium

          NFP- vasmir_0625: 8190 funds, 0.35 mass, 3.67 thrust, 6000 isp, 2.86 EC, Argon

          NFP- pit_0625: 7002 funds, 0.25 mass, 14.8 thrust, 3500 isp, 0.827 EC, Argon

          NFP- rcsblock_pulsedplasma_01: 10 funds, 0.01 mass, 0.12 thrust, 1370 isp, 341.765 EC, Solid Fuel

          NFP- rcsblock_mpdt_single_01: 100 funds, 0.01 mass, 0.25 thrust, 2000 isp, 60.954 EC, Lithium

          NFP- rcsblock_hall_01: 150 funds, 0.008 mass, 0.15 thrust, 1680 isp, 0.133 EC, Argon

          RLA- small_resistojet: 3250 funds, 0.15 mass, 6.6 thrust, 575 isp, 1.525 EC, monoprop

 

Given all of the above, there are several things we can see as far as cost goes.

First off, the FEEP engine looks pretty good. It has a high ISP, but very low thrust, and the cost looks mostly fine, 5500 could remain. Though I might increase it a little to say 7500, to be closer to the ion engine, but not needed.

Regarding the rj engines, they are far too cheap. 15 funds for the small and 90 for the big are hilarious. Thats less than an rcs block for a relatively advanced, highly efficient, electric engine with a  built in monoprop feed system. Bare minimum it needs to be as expensive as a monoprop engine + a little extra. RLA has a couple small monoprop engines that are 150 and 900 funds, which is a good starting point. BUT, RLA also has a resistojet thruster, and it is 36 times more expensive.  I suggest changing the price for these engines to 2250 for the large, and 775 for the small. That represents a much more sensible cost for these relatively advanced engines.

Moving on to the PPT engines, oh are they cool. But my GOD are they a bargain. 50 and 112.5 funds are very low. I understand they are "cheap" and "disposable," but that should play into their performance and limitation of fuel. When it comes down to it, they are still advanced technology that requires precise timing, electrical work, machining, and software. They might be cheap in the world of electric propulsion, but they are NOT sepratron cheap. I would simply multiply the current costs by 10, to give 500 funds for the 22, and 1250 funds for the 33.

Lastly the rj rcs, its not too bad. It falls a little under the NFP rcs blocks in performance, but also doesn't need fancy fuels. I would increase it to 50 funds.

Increasing the cost will still allow these engines to be relatively cheap options when compared to the NFP engines, especially when you factor in the cheap and simple fuels they use (FEEP excluded).

 

Use Case: 

I believe this has been mentioned previously by others, but some of these engines have limited use cases beyond just wanting to use a cool looking engine. The main reasons why being thrust, ISP, and EC usage. (This is also assuming cost is adjusted as discussed above, as that is honestly the most important issue)

I will again go through the engines one by one, making suggestions as I go, along with reasoning for the suggestions.

FEEP

This one is quick, because again it seems fairly balanced with a good use case. It has less thrust than a DAWN, but higher ISP. Cool. But, its mass is a bit low, and the thrust is very small. The mass is half that of the NFP engines. I would increase the mass, and give the engine a little extra thrust to match. I suggest increasing the mass to 0.2, and the thrust to 1.1. This should increase overall EC/s to 55 exactly.  (Edited)

Resistojets

These need love. Look at what you give up/gain versus the other options. Compared to the DAWN, it really is in a rough spot. You get less thrust, less isp and a worse fuel type. All you gain is less mass, and lower cost. Lets change some stuff. Again, I refer to the RLA resistojet. Admittedly, its OP compared to real life, but its much better in terms of balance; it has a defined use case. A resistojets use case is very simple; cheap, more powerful than an ion drive, higher TWR than the ion , same fuel as rcs, lower power usage, and more efficient than chemical engines. The RLA resistojet succeeds in all 6 areas. Yours fails in two of them, thrust and isp. Lets fix that. The DAWN has a thrust of 2, RLA rj has 6.6. How about 4.5 thrust for the big SEE rj, this is three times the current amount. We should increase the mass to 0.14 to keep the mass a little lighter than the RLA, but heavier than the puff engine in stock ksp. For the small SEE rj, lets increase the thrust to 0.9 and again double the mass, so 0.03. BUT, lets give a little incentive to use the small rj, since they are the same "size" (size0, 0.625m). Lets give the small SEE rj a slightly higher TWR over the big one, which can be seen in the lower efficiency too. Lets give the small one a little extra thrust, and give it 1.2 thrust, leading to a 40 TWR compared to the big rj 32.1 TWR (RLA has TWR of 44).  Lastly, the isp needs to increase a little bit. Again, we want our use case to allow a higher isp than chemical alternatives. RLA uses 575, which does seem a bit high. Lets use 470 for the small SEE rj, which places it just beyond most chemical engines, and right at the theoretical limit for LH2/O engines. Then lets use 515 isp for the big one, to incentivize its use. The added isp will also offset the increased thrust, and therefor not change EC too much. (edited)

To conclude this section, the changes are:

          rj_engine_small: Thrust to 1.2, mass to 0.03, isp to 470

          rj_engine_big: Thrust to 4.5, mass to 0.14, isp to 515

These changes will give these engines a fantastic set of use cases

PPT

The pulsed plasma engines are really neat, they just need a few tweaks to give them more incentive to be used. Their distinct use case is: very cheap, very light, relatively high isp, highish TWR, no added fuel needs, accessible EC needs, with the downside of limited solid fuel. Essentially, they are place-and-play-petit-probe-propulsion. From this perspective, they also take inspiration from the NFP PPT thrusters, but a little too much inspiration.  I understand they are thematically 4 NFP PPT thrusters bolted together, but I think we should differentiate a little. The SEE PPT engines are, well, engines, not small thrusters. We can make them feel like engines with some tweaks. Plus, in real life making an engine bigger usually involves more wires, computers, software, and structural support than just strapping them together. So it makes a lot of sense that 4 or 9 single thrusters strapped together would weight more than 4 or 9 thrusters. You have to wire them together, make the wire frame, coat it all in shielding, and so on.

Lets fix that. The isp and EC needs are perfect. Although the fuel amounts on board could use a little extra oomph. If the thrusters get 1 solid fuel per unit, why not up that to 1.5 per unit. This gives them a little more burn time, while still having an overall limit to burn time compared to things like the ion, resistos, and other NFP engines. Mass and thrust also need a little tweaking. First, mass needs to go up. Again, these are advanced engines that use a lot of wire, magnets, and metal. I like that each part uses the mass divided by 4 and 9, representing the number of thrusters. Essentially each thruster with the base SEE numbers weighs 0.01, nice, I like even numbers. Lets increase the mass to 0.015 each, so the 22 is 0.06 mass and the 33 is 0.135 mass. This keeps them much lighter than the DAWN and NFP alternative, while still making a little more sense. Next, thrust. We double the mass, lets double the thrust right? Well not so fast. DAWN has a TWR of 8, the original SEE PPT have 12. Matching 12 would place it at 0.96 and 2.16 thrust for the 22 and 33. Lets make each "PPT engine unit" have a mass of 0.015, and a thrust of 0.3, and 1.5 fuel. This would give  a TWR of 20 instead of 12. This would further differentiate these engines from both the DAWN and a cluster of the NFP PPT rcs blocks. Using this formula, the 22 has a new thrust of 1.2, and the 33 has a new thrust of 2.7. (edited)

To conclude this section, the changes are:

          PPT_22: Thrust to 1.2, mass to 0.06, fuel to 6

          PPT_33: Thrust to 2.7, mass to 0.135, fuel to 13.5

          Each "PPT engine unit": Mass of 0.015, thrust of 0.3, fuel of 1.5

These changes further differentiate these engines from the DAWN and NFP PPT, and make them feel like designated propulsion systems. And of course, they will feel like proper place-and-play-petite-probe-propulsion systems.

 

Compatibility: 

My only suggestion here is regarding the choice of resource/fuel for the new FEEP engines. I see that you have been back and forth on this topic since their inception. You initially had Caesium as the resource (with a neat green flame), then changed it to liquid Indium (and changed to a bluish flame). 

At this point in KSPs development, the modding scene is established and logical. Mods that utilize existing modding framework tend to do better and are more compatible, which ultimately most players just care about compatibility.  The community resource pack (CRP) is an excellent example. It is universally loved, and used. Given that this mod will be downloaded 95% of the time by people that also use the NFP modpack, I see no really valid reason why this mod should differentiate itself by using a native resource.

Swapping to liquidIndium, I think at least, should be reversed. First of all, there is the issue of keeping Indium in a molten state, which would require a lot of EC and weight of heating elements. But even disregarding that,  its not in the CRP.

Caesium is in the CRP. (see below) (Also its melting point is much lower, so that would make more sense too)

RESOURCE_DEFINITION
{
    name = Caesium
    abbreviation = #LOC_CRP_Caesium_Abbreviation
    displayName = #LOC_CRP_Caesium_DisplayName
    density = 0.00193
    flowMode = ALL_VESSEL
    transfer = PUMP
    isTweakable = true
    isVisible = true
    unitCost = 77
    volume = 1
}

My suggestion here would be to revert to the use of Caesium as the resource for this engine set, and adjust the tanks/mod to use the CRP values (density, cost, etc..) This will ensure compatibility when large modpacks are installed, and will allow your mod to have enhanced features like refueling or extra resource tanks without putting any extra effort in on your end. Its a win-win.

Bonus, Caesium burns a very similar color to the current waterfall effects, so you wouldn't even need to change that

 

Sorry for the long post. I really like this mod and want to see it thrive and gain traction. You have done a wonderful job!

I'd love to hear your thoughts on this.

 

 

Edited June 8 by newvegasmatt
After some further testing and honestly tech tree unlocks, I changed a few numbers to better reflect use cases and expected performance. Mainly pertaining to masses of parts.

[triple cheeseburger]

Progress update...

Hello again everyone, it has been awhile since I last posted here but I am once again in the mood to work on KSP modding... I was working on another, much larger project, but I got a bit distracted and decided to come back to this mod to tweak some things and finally try and add the remaining planned features.

On 6/7/2024 at 6:32 PM, newvegasmatt said:

@triple cheeseburger

I just came across this mod, and I have to say that I absolutely LOVE it!

 

From a gap filling stance, it is almost perfect, more on that in a second. I noticed in previous posts that you asked for feedback.

I do have some, and pretty much all of it is very easy to fix.

 

My biggest suggestions are balance, use case, and compatibility.  (In addition to finishing the Arcjets!!! Those sound awesome!)

I apologize in advance for how long and wordy this will be, I will admit I had a little fun with this. Note, that all of the numbers I have listed as suggested changes, I have been using in my own game (with the exception of the Caesium) and love the position of the engines with these new numbers.

 

EDIT: I changed a few numbers after further testing. I will make what was editted.

 

Balance: 

This is the biggest issue, but is also the easiest to fix luckily. This all revolves around cost.

In a nutshell, most of these engines are WAY too cheap. Like an order of magnitude too cheap. (though the FEEP is pretty good)

I'm going to go deep into the weeds and analysis the cost of each engine, its propellant, and similar engines in stock, RLA, and NFP.

I'll use the config names for the engines for ease of locating the files and numbers. (sorry not sorry for the below info dump)

Note: I will use the chart below to reference the use case section as well as the cost balance section:

          PPT_22: 50 funds, 0.04 mass, 0.48 thrust, 1370 isp, 341.765 EC, solid fuel

          PPT_33: 112.5 funds, 0.09 mass, 1.08 thrust, 1370 isp, 341.765 EC, solid fuel

          rj_engine_big: 90 funds, 0.07 mass, 1.5 thrust, 415 isp, 1 EC, monoprop (2.8 EC/s)

          rj_engine_small: 15 funds, 0.015 mass, 0.3 thrust, 395 isp, 1 EC, monoprop (0.8 EC/s)

          SEE_FEEP_engine: 5500 funds, 0.15 mass, 0.8 thrust, 10200 isp, 1 EC, liquidindium (see last section) (40 EC/s)

          SEE_rj_rcs: 18 funds, 0.013 mass, 0.1 thrust, 365 isp, 1 EC, monoprop (0.4 EC/s)

Now for comparable engines:

          STOCK- ionengine: 8000 funds, 0.25 mass, 2 thrust, 4200 isp, 18 EC, Xenon (8.74 EC/s)

          NFP- ionXenon: 3910 funds, 0.2 mass, 2.1 thrust, 6380 isp, 178.758 EC, Xenon

          NFP- ionArgon: 1950 funds, 0.1 mass, 1.5 thrust, 2200 thrust, 0.257 EC, Argon

          NFP- mpdt_0625: 9230 funds, 0.33 mass, 47.3 thrust, 2600 isp, 115.139 EC, Lithium

          NFP- vasmir_0625: 8190 funds, 0.35 mass, 3.67 thrust, 6000 isp, 2.86 EC, Argon

          NFP- pit_0625: 7002 funds, 0.25 mass, 14.8 thrust, 3500 isp, 0.827 EC, Argon

          NFP- rcsblock_pulsedplasma_01: 10 funds, 0.01 mass, 0.12 thrust, 1370 isp, 341.765 EC, Solid Fuel

          NFP- rcsblock_mpdt_single_01: 100 funds, 0.01 mass, 0.25 thrust, 2000 isp, 60.954 EC, Lithium

          NFP- rcsblock_hall_01: 150 funds, 0.008 mass, 0.15 thrust, 1680 isp, 0.133 EC, Argon

          RLA- small_resistojet: 3250 funds, 0.15 mass, 6.6 thrust, 575 isp, 1.525 EC, monoprop

 

Given all of the above, there are several things we can see as far as cost goes.

First off, the FEEP engine looks pretty good. It has a high ISP, but very low thrust, and the cost looks mostly fine, 5500 could remain. Though I might increase it a little to say 7500, to be closer to the ion engine, but not needed.

Regarding the rj engines, they are far too cheap. 15 funds for the small and 90 for the big are hilarious. Thats less than an rcs block for a relatively advanced, highly efficient, electric engine with a  built in monoprop feed system. Bare minimum it needs to be as expensive as a monoprop engine + a little extra. RLA has a couple small monoprop engines that are 150 and 900 funds, which is a good starting point. BUT, RLA also has a resistojet thruster, and it is 36 times more expensive.  I suggest changing the price for these engines to 2250 for the large, and 775 for the small. That represents a much more sensible cost for these relatively advanced engines.

Moving on to the PPT engines, oh are they cool. But my GOD are they a bargain. 50 and 112.5 funds are very low. I understand they are "cheap" and "disposable," but that should play into their performance and limitation of fuel. When it comes down to it, they are still advanced technology that requires precise timing, electrical work, machining, and software. They might be cheap in the world of electric propulsion, but they are NOT sepratron cheap. I would simply multiply the current costs by 10, to give 500 funds for the 22, and 1250 funds for the 33.

Lastly the rj rcs, its not too bad. It falls a little under the NFP rcs blocks in performance, but also doesn't need fancy fuels. I would increase it to 50 funds.

Increasing the cost will still allow these engines to be relatively cheap options when compared to the NFP engines, especially when you factor in the cheap and simple fuels they use (FEEP excluded).

 

Use Case: 

I believe this has been mentioned previously by others, but some of these engines have limited use cases beyond just wanting to use a cool looking engine. The main reasons why being thrust, ISP, and EC usage. (This is also assuming cost is adjusted as discussed above, as that is honestly the most important issue)

I will again go through the engines one by one, making suggestions as I go, along with reasoning for the suggestions.

FEEP

This one is quick, because again it seems fairly balanced with a good use case. It has less thrust than a DAWN, but higher ISP. Cool. But, its mass is a bit low, and the thrust is very small. The mass is half that of the NFP engines. I would increase the mass, and give the engine a little extra thrust to match. I suggest increasing the mass to 0.2, and the thrust to 1.1. This should increase overall EC/s to 55 exactly.  (Edited)

Resistojets

These need love. Look at what you give up/gain versus the other options. Compared to the DAWN, it really is in a rough spot. You get less thrust, less isp and a worse fuel type. All you gain is less mass, and lower cost. Lets change some stuff. Again, I refer to the RLA resistojet. Admittedly, its OP compared to real life, but its much better in terms of balance; it has a defined use case. A resistojets use case is very simple; cheap, more powerful than an ion drive, higher TWR than the ion , same fuel as rcs, lower power usage, and more efficient than chemical engines. The RLA resistojet succeeds in all 6 areas. Yours fails in two of them, thrust and isp. Lets fix that. The DAWN has a thrust of 2, RLA rj has 6.6. How about 4.5 thrust for the big SEE rj, this is three times the current amount. We should increase the mass to 0.14 to keep the mass a little lighter than the RLA, but heavier than the puff engine in stock ksp. For the small SEE rj, lets increase the thrust to 0.9 and again double the mass, so 0.03. BUT, lets give a little incentive to use the small rj, since they are the same "size" (size0, 0.625m). Lets give the small SEE rj a slightly higher TWR over the big one, which can be seen in the lower efficiency too. Lets give the small one a little extra thrust, and give it 1.2 thrust, leading to a 40 TWR compared to the big rj 32.1 TWR (RLA has TWR of 44).  Lastly, the isp needs to increase a little bit. Again, we want our use case to allow a higher isp than chemical alternatives. RLA uses 575, which does seem a bit high. Lets use 470 for the small SEE rj, which places it just beyond most chemical engines, and right at the theoretical limit for LH2/O engines. Then lets use 515 isp for the big one, to incentivize its use. The added isp will also offset the increased thrust, and therefor not change EC too much. (edited)

To conclude this section, the changes are:

          rj_engine_small: Thrust to 1.2, mass to 0.03, isp to 470

          rj_engine_big: Thrust to 4.5, mass to 0.14, isp to 515

These changes will give these engines a fantastic set of use cases

PPT

The pulsed plasma engines are really neat, they just need a few tweaks to give them more incentive to be used. Their distinct use case is: very cheap, very light, relatively high isp, highish TWR, no added fuel needs, accessible EC needs, with the downside of limited solid fuel. Essentially, they are place-and-play-petit-probe-propulsion. From this perspective, they also take inspiration from the NFP PPT thrusters, but a little too much inspiration.  I understand they are thematically 4 NFP PPT thrusters bolted together, but I think we should differentiate a little. The SEE PPT engines are, well, engines, not small thrusters. We can make them feel like engines with some tweaks. Plus, in real life making an engine bigger usually involves more wires, computers, software, and structural support than just strapping them together. So it makes a lot of sense that 4 or 9 single thrusters strapped together would weight more than 4 or 9 thrusters. You have to wire them together, make the wire frame, coat it all in shielding, and so on.

Lets fix that. The isp and EC needs are perfect. Although the fuel amounts on board could use a little extra oomph. If the thrusters get 1 solid fuel per unit, why not up that to 1.5 per unit. This gives them a little more burn time, while still having an overall limit to burn time compared to things like the ion, resistos, and other NFP engines. Mass and thrust also need a little tweaking. First, mass needs to go up. Again, these are advanced engines that use a lot of wire, magnets, and metal. I like that each part uses the mass divided by 4 and 9, representing the number of thrusters. Essentially each thruster with the base SEE numbers weighs 0.01, nice, I like even numbers. Lets increase the mass to 0.015 each, so the 22 is 0.06 mass and the 33 is 0.135 mass. This keeps them much lighter than the DAWN and NFP alternative, while still making a little more sense. Next, thrust. We double the mass, lets double the thrust right? Well not so fast. DAWN has a TWR of 8, the original SEE PPT have 12. Matching 12 would place it at 0.96 and 2.16 thrust for the 22 and 33. Lets make each "PPT engine unit" have a mass of 0.015, and a thrust of 0.3, and 1.5 fuel. This would give  a TWR of 20 instead of 12. This would further differentiate these engines from both the DAWN and a cluster of the NFP PPT rcs blocks. Using this formula, the 22 has a new thrust of 1.2, and the 33 has a new thrust of 2.7. (edited)

To conclude this section, the changes are:

          PPT_22: Thrust to 1.2, mass to 0.06, fuel to 6

          PPT_33: Thrust to 2.7, mass to 0.135, fuel to 13.5

          Each "PPT engine unit": Mass of 0.015, thrust of 0.3, fuel of 1.5

These changes further differentiate these engines from the DAWN and NFP PPT, and make them feel like designated propulsion systems. And of course, they will feel like proper place-and-play-petite-probe-propulsion systems.

 

Compatibility: 

My only suggestion here is regarding the choice of resource/fuel for the new FEEP engines. I see that you have been back and forth on this topic since their inception. You initially had Caesium as the resource (with a neat green flame), then changed it to liquid Indium (and changed to a bluish flame). 

At this point in KSPs development, the modding scene is established and logical. Mods that utilize existing modding framework tend to do better and are more compatible, which ultimately most players just care about compatibility.  The community resource pack (CRP) is an excellent example. It is universally loved, and used. Given that this mod will be downloaded 95% of the time by people that also use the NFP modpack, I see no really valid reason why this mod should differentiate itself by using a native resource.

Swapping to liquidIndium, I think at least, should be reversed. First of all, there is the issue of keeping Indium in a molten state, which would require a lot of EC and weight of heating elements. But even disregarding that,  its not in the CRP.

Caesium is in the CRP. (see below) (Also its melting point is much lower, so that would make more sense too)

RESOURCE_DEFINITION
{
    name = Caesium
    abbreviation = #LOC_CRP_Caesium_Abbreviation
    displayName = #LOC_CRP_Caesium_DisplayName
    density = 0.00193
    flowMode = ALL_VESSEL
    transfer = PUMP
    isTweakable = true
    isVisible = true
    unitCost = 77
    volume = 1
}

My suggestion here would be to revert to the use of Caesium as the resource for this engine set, and adjust the tanks/mod to use the CRP values (density, cost, etc..) This will ensure compatibility when large modpacks are installed, and will allow your mod to have enhanced features like refueling or extra resource tanks without putting any extra effort in on your end. Its a win-win.

Bonus, Caesium burns a very similar color to the current waterfall effects, so you wouldn't even need to change that

 

Sorry for the long post. I really like this mod and want to see it thrive and gain traction. You have done a wonderful job!

I'd love to hear your thoughts on this.

 

 

Thank you for this very in-depth reply! Yeah, I basically agree with like 90% of what you said lol, so I've decided to rebalance a lot of things. Here's the full list of changes coming in the next update and the plans for the new parts I want to add:

Furthermore, here's a sneak peak of the Teacake - the 0.625m arcjet engine:

Finally, something else I'm working on is adding localisation support to the mod. Though depending on how long it takes adding support for other languages might come in patches released after this content update. I've only got the 1.25m arcjet and arcjet RCS left to make, and then this update will be ready (I also plan to come up with some new graphics to use in the original post...) I'm a lot more familiar with KSP modding these days, so hopefully it should not take too long. Any feedback on the balancing changes I have planned, or anything else, is welcome! Thank you for your time.

Edited July 11 by triple cheeseburger
Fixed a goofed up image link

[triple cheeseburger]

Hello once again...

Supplementary Electric Engines v1.3.0 is out!
This is quite a large update, with part balance changes, new parts, and a couple of extra things.

Re-balanced the stats of many parts (Spoilered to avoid making this post too long)

Spoiler

R1 "Fudge":

• Cost: 775 (Previously 15)

• Thrust: 1.2kN (Previously 0.3kN)

• Mass: 30kg (Previously 15kg)

• TWR: 4.08 (Previously 2.04)

• ISP: 430 (Previously 395)

R2 "Toffee":

• Cost: 2250 (Previously 90)

• Thrust: 4.5kN (Previously 1.5kN)

• Mass: 140kg (Previously 70kg

• TWR: 3.28 (Previously 2.19)

• ISP: 465 (Previously 415)

RJ RCS:

• Cost: 50 (Previously 27)

• Thrust: 0.6kN (Previously 0.1kN)

• TWR: 2.45 (Previously 0.41)

• ISP: 405 (Previously 365)

PPT 22 "Pancake":

• Cost: 500 (Previously 50)

• Amount of solid fuel per thruster: 1.5 (Previously 1)

• Base mass: 60kg (Previously 40kg)

• With 6 units of solid fuel the wet mass goes up to 105kg (Previously 70kg)

• Thrust: 1.2kN (Previously 0.48kN)

• TWR: 1.17 (Previously 0.7)

• EC/s: 1.6 (Previously 1.628)

PPT 33 "Waffle":

• Cost: 1125 (Previously 112.5)

• Amount of solid fuel per thruster: 1.5 (Previously 1)

• Base mass: 135kg (Previously 90kg)

• With 13.5 units of solid fuel the wet mass goes up to 206.25kg (Previously 157.5kg)

• Thrust: 2.7kN (Previously 1.08kN)

• TWR: 1.33 (Previously 0.7)

• EC/s: 3.6 (Previously 3.663)

F1 "Sorbet":

• Cost: 7500 (Previously 5500)

• EC/s: 55 (Previously 40)

• Revert fuel to Caesium, use CRP Caesium if the player has it installed, if not use a custom Caesium resource with identical stats.

• Indium tanks now store Caesium instead. Caesium is quite expensive so be mindful of that if you're in career mode!

New Arcjet engines

These engines run on monopropellant and can achieve better specific impulse than the resistojets, but they suffer from a limited lifespan due to the corrosion of their internal electrodes (represented by the small amount of ablator resource stored inside them).

KO-A1 "Teacake" Arcjet Engine:

• 780 Isp

• 5.5kN thrust

• 150kg mass

• 3.74 TWR

• 8 kW input power

• 3,500 funds

• Runs on Monopropellant, 0.625m size

• Unlocked with the "Advanced Ion Propulsion" tech node (when using CTT)

KO-A2 "Gumdrop" Arcjet Engine:

• 805 Isp

• 18.5kN thrust

• 650kg mass

• 2.9 TWR

• 32 kW input power

• 12,200 funds

• Runs on Monopropellant, 1.25m size

• Unlocked with the "Advanced Ion Propulsion" tech node (when using CTT)

Other Minor Changes

• Added configs for VAB Organizer.

• Tweaked FEEP Thruster and Caesium fuel tank textures slightly to make their paint strips more vibrant.

Edited September 8 by triple cheeseburger
Fixed a goofed up image link

[The Dressian Exploder]

YOOOOOO

[NiL]

21 hours ago, triple cheeseburger said:

Supplementary Electric Engines v1.3.0 is out!

Hyyype, thank you. This is one of my favourite mods, it's great, goes just so well with everything

[arbsoup]

The arcjet fills a niche I didn't have many options for, and it looks great. Though I might patch those electrodes to last longer so these stay competitive with small liquid engines in my 10x install.

Small note: the Gumdrop's mounts are listed as "0.625m" and "Compact" when the first should probably be 1.25m.

Edited September 9 by arbsoup