Power and mining/isru

[Rylant]

Hey all, so I have been running the Jool moons with a lander I created which has mining/isru capability. The ship is huge. It has a converter, 4 of the large extending solar panels, 4 of the large extending heat panels, 8 of the RTGs, 1 of the largest batteries, 1 large ore holding tank, 2 drills and a converter. I land, extract all of the panels, deploy the 2 drills, and start the converting process. 
 

So the process continues for a bit and the power slowly drains. A couple game hours later, I run out of power and the drills stop. The power builds until it is full and then I start the drills again. Of course, this takes forever to fill my fuel tanks. This happens through day even without a sunset. Now I understand that Jool tends to be far from the Sun and solar is weak. The strange thing to me is, this process continues for several days of starting and stopping the drills as the power wanes. However, at some point, the process continues uninterrupted without the drills and converting draining the power. I go from getting like 100 delta v, then the power runs out. I build the power and start up again, get another 100 delta v in fuel, and run out of power. This continues for days, and then suddenly the process goes uninterrupted for several thousand delta v without me having to restart. The power doesn’t get interrupted and it keeps going.  I can’t figure out what happens then, to allow the power to keep up. 
 

Any ideas? I may want to look at the power setup more in detail. Obviously this isn’t much of a concern on Moho or in the Eve system as solar is more effective. 
 

Rylant

[jimmymcgoochie]

Use RTGs, not solar panels. One Gigantor is 300kg and produces 1EC/s at Jool and only in daylight, whereas one RTG is only 50kg and produces 0.75EC/s, anytime, anywhere. RTGs are smaller too and unlike solar panels you can’t break them if you bump into them, land a bit badly or forget to retract them in an atmosphere.

[Single stage to ocean]

Keep it running for 6 hours by all cheaty means possible, then you can exploit this and switch to tracking station. 216,000 EC in batteries needed, so you are kind of screwed. Maybe remove solar panels, and just tolerate the terrible slowness. From empty, it is only 60 cycles, which doesn't suck too much with 100,000x warp.(assumes 6k dv). Maybe leave to asunnier place, refuel, then come back and explore. Remove the solar panels b/c according to watching bradley whitsance videos, isru can scale down production as long as the power doesn't change.

Edited May 27, 2021 by Single stage to ocean

[AHHans]

The fast but cheaty way is to switch the drill off to charge the batteries, then switch everything on, confirm that it works and generates fuel, and jump to another vessel outside the physics bubble (or the KSC). Any vessel that is not in the physics bubble doesn't consume ECs, but when you jump back to it then will have produced fuel as if it was running all the time.

The no so cheaty way would be to ensure enough EC generation that is solar independent. You can either have enough RTGs or fuel cells to power everything. (Yes, even with only fuel cells, when powering a large Convert-O-Tron you get a net fuel gain.)

[Starman4308]

At very high timewarp values, I've noticed that EC drain becomes inconsistent with what's experienced at lower timewarp.

As to non-cheaty solutions: it's either RTG spam, fuel cell magic*, or installing a mod like Near Future Electrical which has nuclear reactors.

*At least with an engineer onboard, you gain more EC from burning LF/O in a fuel cell than you lose mining and refining ore to LF/O. Suffice to say, that isn't how things work IRL.

[Snark]

On 5/27/2021 at 1:26 AM, Rylant said:

Any ideas?

Fuel cells. Fuel cells are your friend. Yes, they eat LFO, but as long as you're sitting on a reasonably high ore concentration and have a decently high-level engineer aboard (ideally at least level 3), then there's a net gain (you mine more than you use), and fuel cells provide quite a lot of power. Also, they work continuously, even at night.

Solar cells aren't really useful for mining, out at Jool. They produce very little power per weight, and are totally inactive at least half the time (night)... and if you're on the Jool-facing side of the inner three moons, you've got significant eclipses to deal with, too.

So, RTGs are quite a bit better than solar panels. But you'd need to really spam them to get enough to power a mining/refining rig, so honestly, fuel cells are your best bet.

[Rylant]

1 hour ago, Snark said:

Fuel cells. Fuel cells are your friend. Yes, they eat LFO, but as long as you're sitting on a reasonably high ore concentration and have a decently high-level engineer aboard (ideally at least level 3), then there's a net gain (you mine more than you use), and fuel cells provide quite a lot of power. Also, they work continuously, even at night.

Solar cells aren't really useful for mining, out at Jool. They produce very little power per weight, and are totally inactive at least half the time (night)... and if you're on the Jool-facing side of the inner three moons, you've got significant eclipses to deal with, too.

So, RTGs are quite a bit better than solar panels. But you'd need to really spam them to get enough to power a mining/refining rig, so honestly, fuel cells are your best bet.

Interesting. Honestly, I have literally never used fuel cells. Just the thought of burning precious delta v kills me, especially because I am so notoriously wasteful with it. What I need to do is sit down and actually calculate power production vs consumption. Is that listed somewhere in vanilla? Or are there good energy usage readout mods?

Rylant

[Snark]

1 hour ago, Rylant said:

Interesting. Honestly, I have literally never used fuel cells. Just the thought of burning precious delta v kills me, especially because I am so notoriously wasteful with it. What I need to do is sit down and actually calculate power production vs consumption. Is that listed somewhere in vanilla? Or are there good energy usage readout mods?

Yes, I generally never use them either, for precisely that reason... except for mining/refining.  Because if you're mining/refining, then you have an infinite, inexhaustible supply of LFO right there, so all you need to do is to consume a small portion of it to power the rest.

One nice thing about them is that they're smart enough to only generate power (and consume LFO) if it's actually needed-- i.e., your spacecraft will take power from all the renewable sources (like solar panels and RTGs) first, and only use the fuel cells for whatever demand the other ones can't handle.

Not sure what you mean about "calculate"-- if you look at the stats for the fuel cells (example), it says how fast they consume LFO when they're operating at full power.  The real variable is how fast ore is supplied, since that will depend on ore concentration and engineer skill.  Personally, I never bother with any of this math, because it's basically pointless.  It boils down to this:

• Either you have a reasonably high ore concentration (and a decent engineer), in which case you're fuel-positive and it doesn't really matter how positive it is, because all you have to do is let it run,
• ...or else you don't have enough ore concentration and/or engineer level, so that running on fuel cells would be fuel-negative, in which case there's no point in running at all.

"Okay, well, how much ore is 'enough' to be fuel-positive?" is a reasonable question to ask.  I don't actually know the answer, but in my own gameplay it's hardly ever mattered, because I always land to mine in an area that's shown as "high" for that celestial body, and generally it will be one of two situations:  either this is an ore-poor body and the max concentration is down around 1-2%, or else it's a reasonably ore-rich body and the concentration is up around 7-11%.  I only ever mine the latter, and that's well above the break-even point.

[AHHans]

19 minutes ago, Snark said:

Personally, I never bother with any of this math, because it's basically pointless.

Well, you do need enough electricity generation capability to run all required modules. (SCNR! ) But that math isn't too hard, for a simple setup three Fuel Cell Arrays are enough.

[Snark]

14 minutes ago, AHHans said:

Well, you do need enough electricity generation capability to run all required modules. (SCNR! ) But that math isn't too hard, for a simple setup three Fuel Cell Arrays are enough.

Well, yeah, but each fuel cell array says how much power it uses, and so does the ISRU, and so do the drills. That's just simple arithmetic. I assume the OP was referring to the math around the balance of LFO production versus consumption, which isn't quite as obvious, and that's what I was addressing.

[AHHans]

Just now, Snark said:

Well, yeah [...]

You are right, I just couldn't help myself.
_{(And my first test rig yesterday had only two FCAs...)}

[FleshJeb]

4 hours ago, Rylant said:

Interesting. Honestly, I have literally never used fuel cells. Just the thought of burning precious delta v kills me, especially because I am so notoriously wasteful with it. What I need to do is sit down and actually calculate power production vs consumption. Is that listed somewhere in vanilla? Or are there good energy usage readout mods?

Rylant

The fuel cells will automatically turn off when your batteries hit 95%, so it's better to bring too much than too little.

Power consumption is complex because it depends on the ore concentration, and what level of engineer you have on-board, if any.

Here's a thorough guide. I believe they cut the drill elec consumption in half since this, but that's easy enough to check and plug in to the equations: