Fuel cell?

[lewisd]

Has anyone tried making a "fuel cell" stock, by taking two LV-T30 engines, facing opposite directions, so there is no net thrust applied, and maybe trying to arrange them so they're inside a fuel tank or something, so it doesn't take up too much space? You'd only ever be able to run it at a tiny amount of throttle or the exhaust would destroy things. It might even still, at very low throttle? Does it even generate any power at all with only one or two notches of throttle?

That engine is the smallest stock one I could find that has an alternator. I know that using solar panels or an RTG is way easier, but I'm planning an Apollo recreation mission, and I'm trying to use batteries and fuel cells only on the lander.

[Kromey]

I like where your head is at! I have no idea if this would work, or be even remotely feasible, in the game, but I still like what you're thinking here!

I'm going to watch this thread to see if anything workable comes out of it, and if there's nothing conclusive by the time I can fire up the game (either late tonight or tomorrow evening, sadly) I'll give it some experimentation myself.

[FlamedSteak]

That is actually a really good idea......certainly something to utilise in the early stages of the tech tree when you don't have solar panels available.

[lewisd]

That is actually a really good idea......certainly something to utilise in the early stages of the tech tree when you don't have solar panels available.

Oh, wow! That hadn't even occurred to me. I haven't tried 0.22 yet. Work.

[SRV Ron]

Would be far more efficient if a mod is created that uses fuel and oxygen for power generation. A small doughnut tank should last two weeks while creating the continuous power of a dozen huge solar panels. Would be good for career mode for powering missions needing constant streaming of data back to Kerbal.

[lewisd]

Would be far more efficient if a mod is created that uses fuel and oxygen for power generation. A small doughnut tank should last two weeks while creating the continuous power of a dozen huge solar panels. Would be good for career mode for powering missions needing constant streaming of data back to Kerbal.

Yeah, it would make a pretty cool mod. (Maybe there is one already? I haven't looked.) Unfortunately for me, I'm trying to do it for a stock challenge thread.

[numerobis]

Has anyone tried making a "fuel cell" stock, by taking two LV-T30 engines, facing opposite directions, so there is no net thrust applied, and maybe trying to arrange them so they're inside a fuel tank or something, so it doesn't take up too much space? You'd only ever be able to run it at a tiny amount of throttle or the exhaust would destroy things. It might even still, at very low throttle? Does it even generate any power at all with only one or two notches of throttle?

How about two LV-T30s pointed opposite each other instead?

The amount of power generated depends on the throttle (or the thrust; same thing for a T30).

[Fail-Man 3D]

Yeah, it would make a pretty cool mod. (Maybe there is one already? I haven't looked.) Unfortunately for me, I'm trying to do it for a stock challenge thread.

There are at least two fuel cell mods for .21.1 (one using LF/O or monoprop and one using custom resources), but I'm almost certain they haven't been fixed for .22

[lewisd]

How about two LV-T30s pointed opposite each other instead?

Do you mean pointed at each other, or pointing away from each other?

>= =<

or

=< >=

(where < and > is the nozzle)

I'd be happy if either of them works. And I'm curious what the power output would be if the throttle is only one or two notches up. It may be that it's so low it's virtually useless.

[numerobis]

Away from each other, so you can go full throttle without destroying your spacecraft.

You can test out the throttle:electricity relationship on the pad pretty easily.

[Junafani]

Just tested this in launchpad. It is horribly fuel inefficent.

I used this space craft to test it:

I transmitted one mystery goo sample and that is what is left in the fuel tanks. So one fuel cell used about 3/4 of a T400 and since there are two fuel cells it takes about one and half T400 to transmit one goo experiment.

edit2: Okay, I did another test with same rig, but this time using full power. With full power it used about half a tank per fuel cell. Still not really useful.

Edited October 16, 2013 by Junafani

[lewisd]

Ouch. Yeah, I'd call that "so low it's virtually useless". Too bad. A 0-thrust, higher power/efficiency alternator engine would be a nice mod part.

Oh, wow. I also just looked, and they've increased the power generated by most of the engines in 0.22 (as well as adding an alternator to the nuclear engine), so if it's that inefficient in 0.22, I can't imagine how bad it was in 0.21!

Edited October 17, 2013 by lewisd

[AlexanderB]

A 0-thrust, higher power/efficiency alternator engine would be a nice mod part.

That part already exists, but like previously stated, it doesn't yet work with the 0.22 tech tree, so it needs some fixin'

[numerobis]

While utterly impractical, it seems like a great solution for a challenge.

[Mr_Magpie]

Just paste this into your Command pods/probes

MODULE

{

name = ModuleGenerator

isAlwaysActive = false

activateGUIName = Turn on Fuel Cell

shutdownGUIName = Turn off Fuel Cell

INPUT_RESOURCE

{

name = LiquidFuel

rate = 0.009

}

INPUT_RESOURCE

{

name = Oxidizer

rate = 0.011

}

OUTPUT_RESOURCE

{

name = ElectricCharge

rate = 1

}

}

EDIT: I actually find it more useful in the FLT100 fuel tank...looks cool too.

Edited October 17, 2013 by Mr_Magpie

[Saberus]

Once you unlock them, an intake and a jet engine pointed straight up would make a decently efficient generator for a landed module. At least on Laythe and Kerbin.

[Technical Ben]

Has anyone tried making a "fuel cell" stock, by taking two LV-T30 engines, facing opposite directions, so there is no net thrust applied, and maybe trying to arrange them so they're inside a fuel tank or something, so it doesn't take up too much space? You'd only ever be able to run it at a tiny amount of throttle or the exhaust would destroy things. It might even still, at very low throttle? Does it even generate any power at all with only one or two notches of throttle?

That engine is the smallest stock one I could find that has an alternator. I know that using solar panels or an RTG is way easier, but I'm planning an Apollo recreation mission, and I'm trying to use batteries and fuel cells only on the lander.

I was very very tempted to do this. Perhaps make ant engines generate electricity, and do it that way.

[Kosmic Debris]

Would be far more efficient if a mod is created that uses fuel and oxygen for power generation. A small doughnut tank should last two weeks while creating the continuous power of a dozen huge solar panels. Would be good for career mode for powering missions needing constant streaming of data back to Kerbal.

+1! Some sort of power generation is needed even for LKO...and fuel cells would be an awesome selection once we get into a resource-consumption mode.

[Javster]

Just paste this into your Command pods/probes

MODULE

{

name = ModuleGenerator

isAlwaysActive = false

activateGUIName = Turn on Fuel Cell

shutdownGUIName = Turn off Fuel Cell

INPUT_RESOURCE

{

name = LiquidFuel

rate = 0.009

}

INPUT_RESOURCE

{

name = Oxidizer

rate = 0.011

}

OUTPUT_RESOURCE

{

name = ElectricCharge

rate = 1

}

}

EDIT: I actually find it more useful in the FLT100 fuel tank...looks cool too.

I'll try to change it to monoprop

[cantab]

The LV-N, unsurprisingly, is the best rocket engine in terms of fuel used per electricity unit, but of course it's heavy and late in the tech tree. Next best is the Poodle, but again that's pretty late.

Early career mode, I've found that if you want to transmit you simply have to time it right, and take advantage of your scheduled engine burns to top up the electrics.

Fuel cells and generators would be nice parts to have. Potentially be good on ion drive craft, presumably they'll produce more power for less weight than RTGs, but with the drawback of needing fuel of their own.

[Tex_NL]

... Potentially be good on ion drive craft, presumably they'll produce more power for less weight than RTGs, but with the drawback of needing fuel of their own.

'Burning' LFO to power an ion craft would be EXTREMELY inefficient. You'll get much better results if you'd replace all that LFO weight with Xenon and a dozen large solar panels

[PlonioFludrasco]

Actually I'm working on a LF/OX fuel cell, and I have a question:

1-What's for you an appropriate rate for made it balanced? 0.009LF/0.011OX/0.75charge is balanced enough?

2-I was thinking to made it in various sizes and/or with different attachment rules. Should I made the smaller of the size of a small battery and massless? Should I made it comparable with batteries masses and sizes?

3- Apart from batteries models (that I'm currently using), what stock 3d model do you suggest to use for them? Or do you have a decent model to lend me? You will be mentioned!

4-Where to put them in the tech three? I was thinking before solar panels, not on the very first node but early enough to be useful.

Thanks!!

[Captain_Brian]

Alternatively, I wonder if this method could be used to power a kethane production plant on a dark side of a moon/planet?

You could have engine flames firing straight up in the air as part of the mining facility.

If it isn't efficient enough, I think I might mod in a low thrust/high power generation engine just for this purpose. It's just a cool concept.

[cantab]

Regarding the LFO:Electricity ratio, I'd say you have three main options:

Try and work out what it theoretically "should" be, That requires figuring out what 1 Ec is; Near Future appears to treat it as 1 kilojoule but I'm not sure how Nertea arrived at that.

Balance it against the rover wheels. Basically knock up a few simple rovers, work out their electricity consumption in miles per Ec, and do the fuel cell to give a reasonable miles per gallon figure.

Balance it against the ion engines. From a gameplay perspective I'd say that a fuel cell powered ion craft should have an effective Isp higher than the LV-N but obviously lower than a solar or RTG powered ion craft, and will presumably have higher achievable TWR.

Captain_Brian, the kethane mod already includes a kethane-fuelled generator. I assume (but haven't checked) you could use that to run drills and mine more kethane than the generator burns.

[PlonioFludrasco]

Regarding the LFO:Electricity ratio, I'd say you have three main options:

Try and work out what it theoretically "should" be, That requires figuring out what 1 Ec is; Near Future appears to treat it as 1 kilojoule but I'm not sure how Nertea arrived at that.

Balance it against the rover wheels. Basically knock up a few simple rovers, work out their electricity consumption in miles per Ec, and do the fuel cell to give a reasonable miles per gallon figure.

Balance it against the ion engines. From a gameplay perspective I'd say that a fuel cell powered ion craft should have an effective Isp higher than the LV-N but obviously lower than a solar or RTG powered ion craft, and will presumably have higher achievable TWR.

Captain_Brian, the kethane mod already includes a kethane-fuelled generator. I assume (but haven't checked) you could use that to run drills and mine more kethane than the generator burns.

Thanks, I will try!!