Ion thrusters + engines?

[Brigor]

In my current run I dont have uranium.
Did anyone do the math if its worth to build a ship with ion-thrusters powred by a hydrogen-engine or is a full hydro-thuster setup much better?

[Nightwing]

I haven't played in a while, but I'd imagine that using the hydrogen engines might be a better bet.

The way SE is right now, the hydro engines are pretty glitchy and unreliable, and hydro thrust has more power, anyway. And I don't think the engine can provide sufficient power for atmo/ion thrusters, anyway. At least on a long term basis.

[Pembroke]

Use hydrogen engine to charge batteries and your batteries to power your ion thrusters. The H2 engine consumes a *LOT* of hydrogen so you probably won't be able to feed it enough for constant power but OTOH it provides a high power output (as much as a small nuclear reactor i.e. 5 MW) so it's ideal for recharging your batteries quickly.

[Loues.S.Cat]

If you have a hydrogen tank your better off with hydrogen engins too.
It is entirely possible to power ion thrusters from an engin, but the bigger the craft the less effective this will become. if you need batteries to make up the shortfall from the engins then it is even less effective.
I haven't done the math yet, this is based on personal observation.

[Loues.S.Cat]

Well here we go.
Two identical rigs, but one has a small battery.
they both have 1 engin, 1 o2 generator, 1 laser antenna, 1 small reactor with 0.0001 uranium to start them off. they also have a single cargo container with 100 ice.

both were started at the same time and the battery one reports it will be dead in just under an hour.
The o2 engin has 5.3%ish of a tank left, so we'll see what runs out first! the battery charged from an engin, or the engins stored gas supply.

if the battery one runs out first it should give an idea on what the loss from engin>battery>power compared to engin>power.
if the hydrogen runs out first... then what the hell are you doing Keen? XD

[Loues.S.Cat]

Preliminary results show engins without batteries pulling into the lead very quickly.
Batteries are going to die first and by quite a wide margin it seems.

I'm working on a more accurate test though. Something I can have run itself in the background.

[krzosu18]

Originally posted by Pembroke:

Use hydrogen engine to charge batteries and your batteries to power your ion thrusters. The H2 engine consumes a *LOT* of hydrogen so you probably won't be able to feed it enough for constant power but OTOH it provides a high power output (as much as a small nuclear reactor i.e. 5 MW) so it's ideal for recharging your batteries quickly.

5 MW is for the engine on the large grid though - for small grid the power is 0,5MW whis is kinda low so you will need more hydro enines to replenish batteries -2-3 should be enough tho for shortl flights.

As for ione well if your main aim is stocky and small frame - then ions help in that regard greatly.

after all hydros need all the extra "plumbing - aka tubes need to be spread around the ship to provide fuel etc - and that can impact the design size considerably - multiple hydrogens or the hydro tank doesnt help in that regard either.

So for civilian ships - hydros are okay - for military ones - ions are more versatile and more resistant to battle damage (aka they dont need fuel so a broken pipe wont affect them - and hydro ones can be knocked out more easly by this...

[Loues.S.Cat]

Well after 40 minutes the battery is down to 14% of the charge it got from an engin with 100 ice

While the engin that didn't charge a battery still has 39% of the hydrogen load it got from its 100 ice.

both of them are powering identical loads so I'd say that proves conclusively that charging a battery from a hydrogen engin is a grose waste of power.

But I am sure there are some situations where it is just needed.

[Buzzard]

Batteries are better than they used to be, but the handling is still a little... off. When set to 'Auto', they will charge to 100%, then start discharging for a moment before going back to normal. Since batteries don't charge at 100% efficiency, there's a perpetual drain on the system.

They're great for enabling for peak usages, where there is not quite enough power supply, then putting back to recharge-only.

[Loues.S.Cat]

Just to be clear on this, batteries should only be charged from wind/solar wherever possible.
Batteries have at least a 20% inefficiancy which means if you are charging them from other sources you are wasting 20% of all the power that goes into them. This includes batteries charging other batteries.
You should not have batteries on recharge or auto while reactors or engins are enabled if you can avoid it.

[Xilo The Odd]

yeah hydrogen engines are literally for escaping planetary gravity or landing on one easily. it requires a lot of fuel to do this though. so if its a ship designed for that task hydro thrust is the way to go, for general space travel ion is your best bet for manuevering and scootin through the universe.

[RoofCat]

here you go, ions are basically stupid except with uranium reactors or on big space freighters with solar -

Originally posted by RoofCat:

So the almighty math (small grid):

Ion thruster - 14.4kN; -200kW
Hydrogen thruster - 98.4kN; 80 l/sec. Menu states 1.25hL (=125 l), but that's not correct.
Hydrogen engine (generator) - 100 l/sec (1.0hL); +500kW (actually +500-1=499kW)
On a sidenote you make 10oooL fuel from 1oookg ice.

So hydrogen thruster would make 98.4*(100/80)=123kN thrust from 100L fuel.
Power generator would make 500kW from 100L fuel.
Which could be used with ion engines to produce 14.4*(500/200)=36kN thrust.


So burning the same ice you can have 123kN directly with hydrogen thruster or just 36kN after all the conversions with ion thruster. Which means hydrogen thruster would accelerate you 3.4x more with same total mass ship spending the same fuel amount. F=ma or a=F/m.
Since you have 3.4 times more force you also have 3.4 times better acceleration.


Now why the hell would anyone reading this want to use ion thrusters with ice and hydrogen fuel power generator ("engine") ever again?

[Karmaterrorᵁᴷ]

Originally posted by Loues.S.Cat:

Well after 40 minutes the battery is down to 14% of the charge it got from an engin with 100 ice

While the engin that didn't charge a battery still has 39% of the hydrogen load it got from its 100 ice.

both of them are powering identical loads so I'd say that proves conclusively that charging a battery from a hydrogen engin is a grose waste of power.

But I am sure there are some situations where it is just needed.

This is interesting. Iv been using them purely as a backup power source to techarge batts in the field.

But now im questioning if thats a good idea.

Part of me says yes it still is because i skip a tonne of ice mining and hydro production not using it as main power. And the power from wind to recharge is free.

But then part of me is saying if its wasting power that way would i be better just using the engine as an outright power plant for the car.

What you think on this?

[krzosu18]

Originally posted by RoofCat:

here you go, ions are basically stupid except with uranium reactors or on big space freighters with solar -

Originally posted by RoofCat:

So the almighty math (small grid):

Ion thruster - 14.4kN; -200kW
Hydrogen thruster - 98.4kN; 80 l/sec. Menu states 1.25hL (=125 l), but that's not correct.
Hydrogen engine (generator) - 100 l/sec (1.0hL); +500kW (actually +500-1=499kW)
On a sidenote you make 10oooL fuel from 1oookg ice.

So hydrogen thruster would make 98.4*(100/80)=123kN thrust from 100L fuel.
Power generator would make 500kW from 100L fuel.
Which could be used with ion engines to produce 14.4*(500/200)=36kN thrust.


So burning the same ice you can have 123kN directly with hydrogen thruster or just 36kN after all the conversions with ion thruster. Which means hydrogen thruster would accelerate you 3.4x more with same total mass ship spending the same fuel amount. F=ma or a=F/m.
Since you have 3.4 times more force you also have 3.4 times better acceleration.


Now why the hell would anyone reading this want to use ion thrusters with ice and hydrogen fuel power generator ("engine") ever again?

well the raw calculations are nice - but there are additional factors to this - if you place even a single battery - that will remove the bottle neck that is mentioned above completely (at the cost of some additional mass).

Another factor is the mass of the plumbing needed to actually power the hydrogen thrusters on the scale of the enitre vessel - but either way bit by bit that mass is acumultaing.

So yes in essence hydor thrusters can be better but they are in essence bulkier on the design , make the battle damage that more dangerous (aka ruptured lines = loss of thrust) and the mass of the plumbing tears down that initial edge over ions.

while with ions you just place the thuster and thats about all you have to worry about (except the power to run it ofc) .

So atm i would say that ION based ship with enough batteries to power all them att 100% thrust would be better for combat vessels due to smaller frame needed and better handling of battle damage. on such designs you dont even need the power generation at all - aka charge the vessel at base or temp carrier and then off you go to do whatever you intend to do.

Such aproach is best mass wide - aka less mass - the better acceleration.

This can be even more visible with self repairing designs - aka on ion ship you just place welder close to engines (but there is also the plumbing to cargo storage to hold the parts ofc - on hydro ship - you might also need toconsider repairing any potential ruptured fuel lines - that increases bulk even further and mass as well.



Ofc you can add tank, possible oxy gen and hydrogen power engine/s to add the ability to recharge while on flight - but that would increase the mass thus impacting the performance...

I guess in the end much is up to personal preference - aka you want sleek and tough to knock out vessels - you go for ions only with batts.

You want to go for more versatile vessel (aka to go in and out of atmo for eg) then mix in hydros or go full hydros all the way - but that makes design larger and bulkier, and heavier and possibly more combat fragile vessel - all of which are perfectly okay for civilian use i would say :D

[RoofCat]

Originally posted by krzosu18:

- snip -

sure hydrogen is bulkier. Even more so considering I would recommend two tanks on all sizes. Because compared to average small grid atmospheric ore miner for example batteries would have roughly twice the capacity.
But to charge those batteries, you would use a ton of electricity. Few times more than converting ice and flying hydrogen. So that would mean more time needed to gather that power or more expensive infrastructure.

Different factor is ice availability. You have to dig some first. And then conversion takes a bit of time too (~20min with balanced design). But on the other hand fastest battery charge at base is 15min. Can't do faster full charge. While stockpiling hydrogen tank from one in base 0 to 100 will take somewhere around 2 min or less.
So if you sit on ice asteroid struggling with solar charging in space or on polar/lake on earth and tired of waiting 15 min each time to move electricity around, hydrogen is still the way to go.

As for battle ships - yes, tank is sensitive. But then what kind of battle ships are you building?
I for example don't add H2 generator or engine to small one at all. Battles are short, have few bottles in your cockpit. Just charge at station and fly with 2 small batteries, tank and connector very light. Very high flight dynamics, frontal armor only.
Can easily capture all freighters. Well, any ship can as it is more about missiles than shooting eventually. Ok, but let's not divert into general stupidness of fighting in SE.

So Ion ship would have more redundancy and no single sensitive tank - that's very serious advantage. Unfortunately to have the same dynamics hydrogen has, you would have to use 7 thrusters in each direction instead of one hydrogen. Because of the same kN issue.

Sure, 7 ion thrusters generate only 7+6 extra blocks compared to single hydrogen thruster. 6 directions that's 6*(7+6)=78 blocks extra. Now 7*6 thrusters would require up to 7*6*200=82MW. Which is 21 battery. Ok, you don't use all directions at once. But you should have at least 2 covered for any realistic battle maneuver. Better actually 3, but lets stick to caferul flight maneuvers during hectic battle a professional pilot would do. So 1/3 of that or 7 batteries.
Single battery needs 3*3*2=18 blocks. 7*18=126 blocks.

So we are at 78+126=204 extra blocks for ion to replace hydrogen. While single hydrogen tank is 5x5x5=125 blocks. And since hydrogen needs some minimal electricity too - for beacon, gyroscope and stuff, lets say we add 2..4 of the new small batteries. Which is enough for hydrogen. That would be extra 4 blocks.
Regular battery weights 1040kg in small grid, small one 121kg, hydrogen tank 3161kg.
Ion thruster weights 121kg while hydrogen one 334kg.

Ion mass (thrusters+batteries) 42*121+7*1040=12362kg
Hydrogen mass (thrusters+tank+batteries) 6*334+3161+4x121=5649kg

So again, which one is less - extra 204 blocks and 12362kg on ion to be able to replicate hydrogen power created by 129 extra blocks and 5649kg?



Sure, this is a bit one sided.
That ion ship should go for a bit longer in the end as batteries have quite high capacity for size (small battle ship fighting for hours with titans, why not). The 2 tank issue mentioned at start.
It would also have excellent redundancy which is very important in battle.

But so is your report. You talk about all the extra size on hydrogen completely neglecting the fact that ion flies like crippled snail unless you add multiple or much larger engines compared to any hydrogen setup. Sitting duck in a battle. It's very weak and slow compared directly.



I had hydrogen ore scout. Switched to ion one to reduce size once I got ton of uranium. It could fly forever and was lighter. But for gods sake it sucked at acceleration!
I needed 4km to get full speed and then 4km to stop. Flying between asteroids 4..10km apart on average. Yeah, you got the picture.

So I added more engines to make it more like hydrogen. The problem with ore scanner - you have to bend around asteroids close to their surface, so you need high power in at least 4 directions. It became bigger (close to hydrogen or worse due to exhaust safety range), quite ugly, spending a lot more uranium by now. So I kind of went back to hydrogen.
Pick up some ice when you run out of fuel, few small batteries to sustain that for days, simple, low part count ship.



Both ways are fine. Do whatever you like. It's just the math is rather ugly for ions too. And you rather shouldn't use ice/hydrogen power generators ("engine") to fill them up.

[Nightwing]

What kind of ore scout did YOU build? My version of an ore scout is a simple unmanned drone. Even being that small, it has a camera, two reactors fed via small junction block from a small container, a gyro, an ore detector, a control panel, one thruster in each direction, a remote control block, an antenna, and a landing gear. all on a 3x3x5 small ship grid.

https://steamcommunity.com/sharedfiles/filedetails/?id=320892977

https://steamcommunity.com/sharedfiles/filedetails/?id=320892868

Granted, the design is old, but I still think it would be a pretty viable design even now for asteroid prospecting.