I went around the Mun once with 24 batteries and still ran out power.

[Gus]

I just flew to the moon and back without landing. I couldn't open my chutes when I got home because I had no power, apparently. Am I missing something? I made it home in under 18 hours. It looked like 24 batteries would easily be enough charge. As far as I know, my sputnik pod was the only thing consuming power.

Edited October 18, 2013 by Gus

[DevoidLight]

What parts do you have on your ship?

[SRV Ron]

When not in actual use, turn off SAS. Leaving it on will drain batteries. My first Mun orbiter of career mode has no extra batteries.

[Wallace]

I find the worst things for guzzling power are reaction wheels.

[Gus]

Here's a picture

I only turned on my sputnik pod when I needed it and I didn't use any reaction wheels in the upper stage that went to the Mun.

Edited October 18, 2013 by Gus

[Dave Kerbin]

Assuming the craft was just drifting it would have 23.5 hours of power.

If the mission was 18 hours you'd have at least 500 units of spare power to work with.

However several things consume power. The reaction wheel consumes power whenever it needs to stabilize the craft. The more massive (and that ship is big) the more power that is used to finally get it stable. You can save a lot of power once in space by turning off SAS when you need to change orientation and just give a slight nudge in the right direction. Your ship will slowly spin on its own (since SAS isn't try to stop it). When you reach the right orientation give a little nudge in the other direction to slow down and then engage SAS to fully stabilize. By not fighting against SAS the whole time you save power. Since most maneuvers in space are planned well in advance you can afford to use this slower means of turning.

I also see a transmission dish. Sending a transmission uses a lot of power (30 on the antenna, I haven't used the dish yet). How many reports did you transmit? A little over a dozen reports, combined with SAS, would have used up your power allowance.

[Gus]

Assuming the craft was just drifting it would have 23.5 hours of power.

If the mission was 18 hours you'd have at least 500 units of spare power to work with.

However several things consume power. The reaction wheel consumes power whenever it needs to stabilize the craft. The more massive (and that ship is big) the more power that is used to finally get it stable. You can save a lot of power once in space by turning off SAS when you need to change orientation and just give a slight nudge in the right direction. Your ship will slowly spin on its own (since SAS isn't try to stop it). When you reach the right orientation give a little nudge in the other direction to slow down and then engage SAS to fully stabilize. By not fighting against SAS the whole time you save power. Since most maneuvers in space are planned well in advance you can afford to use this slower means of turning.

I also see a transmission dish. Sending a transmission uses a lot of power (30 on the antenna, I haven't used the dish yet). How many reports did you transmit? A little over a dozen reports, combined with SAS, would have used up your power allowance.

So is it true that the sputnik pod consumes about 100 units of power per hour (1.7 x 60) even when the torque is turned off, while a one man capsule consumes no power at all?

This seems a bit strange.

Oh, and I sent no data.

Edited October 18, 2013 by Gus

[Eric S]

I find the worst things for guzzling power are reaction wheels.

The worst is MechJeb controlling the reaction wheels. It always wants to correct the heading, and it always corrects at full power.

[Dave Kerbin]

So is it true that the sputnik pod consumes about 100 units of power per hour (1.7 x 60) even when the torque is turned off, while a one man capsule consumes no power at all?

This seems a bit strange.

Oh, and I sent no data.

The torque (reaction wheel) is a seperate system and consumes additional power when it is used. And Kerbals apparently consume no food and require almost no life support beyond a suit to prevent depressurization. There has been some speculation that Kerbals are plants. So yes, for the moment the manned capsules consume no power, apart from the cost of using the reaction wheel.

The probe cores do require power to operate, they are computers that automate what a living Kerbal usually does. If the ship runs out of power the computer will turn off.

A few notes:

If you have a ship with solar panels that runs out of power, and the ships drifts into a position where the solar panels get sunlight the batteries will recharge and the probe core (if present) will reboot, letting you regain control of the ship.

If you have a manned ship that also has a probe core(s) then the probe will be using power even when a Kerbal is present. As of 0.21 a probe core couldn't be manually shutdown (the reaction wheel could be disabled but not the probe itself) so if you built a manned ship with several satellites to be detached they will all consume power from the ships reserves, unless they have a mechanism to generate power on their own (if they are stowed their solar panels might be blocked).

[Gus]

Thanks everyone. I've been playing with a reactor strapped to my ships for so long I forgot about electrical management.

I figured an unmanned pod would consume less power than a manned one. It doesn't.

[Alexandicity]

Maybe I missed something, but why no solar panels? I see no reason you couldn't slap a couple on the side of your craft. Even the single-pane fixed panels would be more than enough to power you!

[Crush]

Maybe I missed something, but why no solar panels?

He hasn't researched them yet?

[Gus]

He hasn't researched them yet?

Correct....

[toomuchbrew]

Did anyone notice that you can run an engine with no power? It was one of the small orbital engines. It still worked at zero power with a manned capsule. I don't remember ANYTHING working when power levels were zero. I noticed that the small engine didn't add to the electrical power like the main engines do either, so maybe that is why.

[numerobis]

A kerbal can run things using manual overrides and their own body heat; that's always been the case. Since 0.21, the reaction wheels require power, so you can't turn without power.

[Diazo]

One catch that got me a few times is that the unmanned drone controllers consume power 2 ways.

First, they have a small, continuous draw that can never be turned off. Then they have the larger draw when the reaction wheels are active.

So when an unmanned command module is using its reaction wheels, its total electricity draw is the sum of those two values.

I did a couple early ships looking only at the reaction wheel draw as it was the bigger electricity drain.

Oops.

D.

[Traches]

A kerbal can run things using manual overrides and their own body heat; that's always been the case. Since 0.21, the reaction wheels require power, so you can't turn without power.

Unless you have a gimballing engine.

[Eric S]

Did anyone notice that you can run an engine with no power? It was one of the small orbital engines. It still worked at zero power with a manned capsule. I don't remember ANYTHING working when power levels were zero. I noticed that the small engine didn't add to the electrical power like the main engines do either, so maybe that is why.

Actually, that's the difference between manned and unmanned craft. An unmanned craft with no power is a ballistic projectile, a manned craft with no power can still do anything that doesn't require power.

As for the engines, some engines generate power, some don't. The larger the engine, the more likely it is to generate power, but that's not a hard rule, the Atomic Motor for example, doesn't.