LV-909 produces no electricity?

[Hakkonen]

So, it's early days yet at the Kerbin Space Agency, and the LV-909 is my go-to motor for orbiter stages. I'm not quite up to landing, yet. Trouble is, it produces no electricity, meaning no transmissions and limited SAS run-time. Both the LVT-30 and LVT-45 produce power when running, why not the LV-909?

[FenrirWolf]

Can't say I know why it doesn't, but it doesn't. In which case you'll need to have other means of storing or generating electricity when using those engines. When I did career mode I found that researching some batteries and sticking a number of them on my ships was enough to tide me over until I unlocked solar panels and other varieties of engines.

[Tank Buddy]

It doesn't have an alternator, as in the part that produces electricity. Not much you can do about it.

[RocketPilot573]

Many engines don't produce power.

[numerobis]

The T30 and T45 are much heavier, too. I guess somekerbal figured the alternator wasn't worth the mass.

[FuzzyLlama]

Maybe tweakables will change that in 0.23... adding generators to smaller engines?

[SunJumper]

The larger engines have alternators to prevent probes from dying and to allow the SAS to work during launch without having solar panels extended. The LV909 was not designed for use as a launch engine, and so has no alternator.

[purpletarget]

The upshot is that the 909 is gimbaled, so you don't need to use the reaction wheels to hold a heading during a burn. Thus you can save a lot of power by turning off the reaction wheels for most of the flight, with possible exception of an occasional orbital reorientation, and maybe during landing.

As for why it doesn't generate power...different engines have different trade-offs. The 909 has never generated power ... but I don't know if it's purely for gameplay balance, or based on some real world motor designs like the LMDE...which looks to have not required the alternators and turbopump arrangements are seen on the terran LVT-30/45 analogs.

[Johnno]

Please consider carefully where you place new threads, this one was in the wrong subforum. Rule 2.4 is in effect, repeated offences may lead to infractions.

Thread moved.

[DrMonte]

That could be a good idea for tweakables - adding/removing generator in cost of weight+trust. We'll see what we'll get in 0.23

[ComradeGoat]

I can understand the 909 not producing electricity. What I can't understand is why the NERVA doesn't, given that it's a nuclear reactor in an engine.

[Temeter]

I can understand the 909 not producing electricity. What I can't understand is why the NERVA doesn't, given that it's a nuclear reactor in an engine.

The NERVA only uses the heat of it's nuclear reactor, so it doesn't need to carry the equipment responsible for converting heat into electricity. Afaik the real engine doesn't even use a liquidfuel/oxidizer-combination.

[bsalis]

You could argue either way that the LV-909 should have an alternator or not.

Personally I think it made sense that it did not have one when it was the smallest engine in the game, and electricity didn't matter so much. Now with an even smaller (and quite OP) engine available, and electricity so critical, an alternator should probably be added. Or mebe the tech tree will allow you to upgrade it sometime.

Not sure why you posted an LV-909 discussion thread in this section of the forum, but anyhow.

[Kasuha]

I can understand the 909 not producing electricity. What I can't understand is why the NERVA doesn't, given that it's a nuclear reactor in an engine.

Last time I was getting into orbit with just one Nerva engine as my last stage, my battery was recharging during the burn.

Anyway, nuclear power plants are actually steam power plants. The nuclear material is only used to generate heat which is then used to make that steam.

[celem]

Indeed, adding the steam turbine component to a NERVA should probably result in an even longer engine model with even more mass. Cant say i've noticed if the NERVA charges my batteries, must admit i always assumed it did, but never relied on it.

I'd agree with the others who have said that the 909 is not a launch engine and therefore has no alternator, makes good sense to me that ascent engines are the ones generating power. You can abuse this slightly if power is really an issue and you dont have the required tech. Mount a symmetrical pair of small tanks horizontally somewhere on your launcher and stick an electricity producing engine on them. Light them both together and they will cancel each other's thrust while producing power. This is laughably inefficient and pretty stupid viewed from the real-world perspective... but if you gotta have juice...

[Sirrobert]

You have more than enough power out of a few batterys when going to the Mun. Just don't transmit all the time and you'll be fine. Bring the samples home. That's the tradeoff for a good engine

[SpeedDaemon]

Last time I was getting into orbit with just one Nerva engine as my last stage, my battery was recharging during the burn.

Anyway, nuclear power plants are actually steam power plants. The nuclear material is only used to generate heat which is then used to make that steam.

We (humans) have sent several nuclear power plants into space, and none of them use steam. I wouldn't consider it OP for the NERVA to also count as an RTG (or some fraction of one).

[Wahgineer]

^What he said.

If you looked into it, you'd actually find that not all reactors need steam to generate power.

How could they get the RTGs to be so small anyway?

[numerobis]

Anyway, nuclear power plants are actually steam power plants. The nuclear material is only used to generate heat which is then used to make that steam.

Turbines are very efficient when mass doesn't matter. But for space, you just stick thermocouples on the reactor, and radiate the heat to space (which is where it was going anyway). The LV-N keeps threatening to overheat; might as well use that heat for something!

Edited November 14, 2013 by numerobis

[UmbralRaptor]

I can understand the 909 not producing electricity. What I can't understand is why the NERVA doesn't, given that it's a nuclear reactor in an engine.

The LV-N and aerospike gained alternators in 0.22. I still raced to solar panels, though.

[KASASpace]

Well, I consider the LV-909 an upper stage engine, not requiring power generation for tht would be too heavy, however, in my opinion I consider the RL-10 the IRL counterpart, and it weighs a lot less than half of a ton, so, who knows?

[Sirrobert]

Well, I consider the LV-909 an upper stage engine, not requiring power generation for tht would be too heavy, however, in my opinion I consider the RL-10 the IRL counterpart, and it weighs a lot less than half of a ton, so, who knows?

Why is it that some people dig up a month old thread, that has already been awnsered, JUST to awnser it again?. WHY?

[Liowen]

The LV-N and aerospike gained alternators in 0.22. I still raced to solar panels, though.

In career I would do the same thing myself, but even in sandbox I put solar and generators on all my crafts. I do this as you should always have a backup system in place in case of things happen that you cannot control, and in career mode I would think you would want that as well. If I do a career mode I would want solar at the very least before doing a manned mission to Mun or Minmus to be honest.

[Vanamonde]

Why is it that some people dig up a month old thread, that has already been awnsered, JUST to awnser it again?. WHY?

Because they're attempting to participate and be helpful.