Variety for Power Generation

[autumn pecan]

I used to play space engineers, any future plans on increasing variety for power generation? like solar panels or hydrogen engines? since there is already a fusion reactor which is advanced technology it would be much more reasonable to add older tech

for hydrogen engines, there would be additional device to process Ice like H2/02 generator and some hydrogen tanks.

also Ice for mining? or a cargo resource i guess

[gloomy mountain]

⚡ pew pew ⚡

[vast prairie]

Solar panels would be cool but they're inferior for intra-system travel because the further away from the sun you get the less useful they are. I know that solar panels are significantly less effective on mars, but Ganymed has an orbit that gets close to earth and then halfway to jupiter, so it wouldn't be nearly as effective as you would hope. That said, there's still some solar energy at Ganymed's furthest point from the sun, so someone should do some math and figure out if the solar energy would do anything significant for our ships systems. I still think it'd be nice to add them, anything more to make me independent is great

And also, hydrogen engines in space engineers are complete wack. They burn hydrogen without oxygen, which makes no sense. And I reckon anything that burns oxygen in this game wouldn't be worthwhile economically to use. Humans are expensive enough ;)

[acoustic tinsel]

Aight, so I did that math, and if I mathed correctly, a one square meter solar panel operating at 20% efficiency at a distance of 2.66AU comes out to roughly 924 Watt-hours produced a day, assuming consistent exposure to direct sunlight.

So, if we divide the total capacity of a ship battery (80.96kWh) by 924, it would take approximately 87.6 days to recharge a single ship battery from 0 to full with a one square meter solar panel

[vast prairie]

Oof

[acoustic tinsel]

Now, worth noting that, iirc, each tile in Ostranauts is supposed to be 1/3m, so a one square meter solar panel would be a 3x3 setup

[long patrol]

Or each one provides a 40W constant trickle charge to the batteries.

[vast prairie]

You can totally assume that the efficiency is higher tho. For example we would defo have 60% efficient ones by the time this game starts

[long patrol]

But that would be on the outside, and probably vertical. So like a 3x1 wall or whipple.

[vast prairie]

That’s only a 3 times increase tho

[acoustic tinsel]

Oh yeah, for sure. I was just working off the real world numbers I could find to start with

[vast prairie]

Ah fair nuff.
Also hang on. We’ve got micro fusion reactors! We would definitely have something closer to 80% efficiency solar panels by then. I’m basing that off the assumption that the maximum possible limit is 86%

[acoustic tinsel]

I mean, the actual efficiency achieved is kind of up in the air for debate. Like, with fusion becoming so readily available and producing the abundance of power that it does, would we even continue to work to develop less efficient forms of power production?

Like, realistically, I still them being used, for sure, especially for like rogue colonies, starter independent settlements, and the like, but the odds of research into improving them being funded when a fusion reactor can be built into a 4mX5m space seems unlikely to me

All that said, I am working on getting a solar panel mod put together. Not entirely sure how realistic I will be able to make them operate, though. Like, distance from the sun, I can definitely work with to at least make brackets of solar irradiance based on distance, but like, requiring direct light on the solar panels on the ship map itself, I am not sure if I could do that, as I haven't at all looked into seeing if there is a variable around how illuminated something is, and if there is, whether or not it differentiates further than just "has light" and "does not have light". If that's the case, the whole thing could be cheesed just by having wall lights shining on your solar paneling

[gloomy mountain]

Something to note about the discussion of how efficient solar panels would be relative to this game's fusion reactors is: The efficiency isn't about how advanced the tech is. Getting that far away from Sol increases the spread between photons which is what we capture for power. You can have the best tech that could utilize 100% of all energy that touches it and it just wouldn't matter, there is only so much energy coming off the sun and it disperses as it gets farther from the source and we can't really change that physical law of the universe

If you want to look it up and learn more the name for this is "Inverse Square Law"

[acoustic tinsel]

Yeah, that's basically how solar irradiance at X distance is calcualted 🙂

[gloomy mountain]

I know the game has fusion tech but that's not wholly out of the question of real physics, but solar tech just has a physical ceiling and we're really familiar with it

[acoustic tinsel]

That said, having a few dozen square meters of solar paneling at 60% efficiency of the panel could potentially still work as a viable option for a smaller ship even as far out as Ganymede 1036. It wouldn't be a great option, but if the price point per panel, and maybe more importantly the mass point, is low enough, it could be a decent intermediary between just running on batteries alone and having a fully functioning reactor

[gloomy mountain]

Yea, I think more power options would be only a good thing for the game and solar panels having low effectiveness unless you make it a large array actually helps keep the game's current oppressive feeling anyway

[acoustic tinsel]

Fun note for comparison here: That square meter of 20% efficiency solar paneling that only produces 924Wh a day at 2.66AU (Ganymede's distance from the sun) would produce ~12.6kWh a day at 0.72 AU (Venus' distance from the sun)

[twilit mica]

Well it could get interesting if you have access to solar cells in foil form, which is technology that already exists (https://www.pv-magazine.com/2022/02/23/solar-foil-for-bipv-applications/) though currently not that great in efficiency, but who knows what a few more decades of development would lead to.
This would allow for very large but still lightweight and cheap extendable solar arrays that could basically be rolled out like retractable awnings for a balcony. I could see that as a standard emergency feature for larger ships to at least run life support while waiting for rescue and with the small salvage ships it would be interesting to extend your operating time. Even if it just covers half your energy consumption that would already double the time you can spend salvaging.
Maybe a subfloor version that extends below the ship?

[autumn pecan]

trickle charging to support life systems would be enough i guess

guys im not sure, but i think your values on solar panel power is a bit off, since there is little barrier to sunlight in space
so im not sure on the efficiency values same to the ones here on earth

maybe we need some data on the charging of satellites with solar arrays irl

[long patrol]

The ISS has 2500m2 of panels that generates 240kW if it stayed on the sunny side of Earth. So 1 m2 panel is ~0.1kW. But that's around us, not Jupiter.

[acoustic tinsel]

Nah, I double checked it, and am more than happy to step by step the math with you, if you'd like. The calculations used are designed around nothing impeding solar irradiance. As Robyn said, the Inverse Square Law is the biggest governing factor here, and it is a harsh mistress in terms of solar irradiance received at astronomical distances.

Interesting enough, we are actually high-balling the number using 20% as our baseline efficiency, as the ISS solar panels average about 14.2% efficiency, meaning my numbers are a little higher than what we see in the real world today.

Well, second biggest governing factor, I suppose, with the solar constant of ~1361W/m^2 at 1AU being the primary factor

[amber crescent]

Radioisotope thermoelectric generators aren't used just for fun in trans-marsian missions.

[patent kayak]

it would be very fun to have to manage cabin heat coming off an RTG once the fire update is out, ngl

[twilit mica]

Well a RTG produces power from the flow of heat between a hot and a cold side so while you might want the hot side to be as hot as possible you definitely want the cold side to be reasonably cold. For probes you put the thing inside to act as a heater to prevent the electronics from cooling down too much and you could use a small RTG the same way. Instead of a heater that uses electricity you would put a RTG and keep temperature reasonable with a cooler. As far as large RTG goes I have at least never heard of such a thing. My guess is that it wouldn't be mass efficient enough to be worth it and too much of a cooling issue as a RTG outputs much more (as far as I found more than 10x as much) heat than electricity.

[gloomy mountain]

What if instead of always disposing of waste heat in radiators we implemented Stirling Engines. They'd be installed on a wall and touch rooms on both sides (like how pumps do) and only generate power relative to the thermal gradient between the rooms. Kinda, goofy and requires a weird setup that doesn't dispose of waste heat which would probably get interrupted by airlock cycling, tbh

I also think a monoprop fuel cell where you just use any stored gas to turn a dynamo for emergency power could work to keep from having to call PASS to go to the station and buy a new battery if you run out before you dock would be nice