uranium fuel value (math!)

[pichutarius]

my first post after 1000+ hours of gameplay. great game!
i post to verify my calculation. please point out any mistake.

(A) quick answer for math allergy people
assuming no neighbour bonus:
= 5GJ
= 15GJ
= 507MJ

(B) derivation:
1. kovarex enrichment processing
= 3
2. nuclear reactor and nuclear fuel reprocessing
= 8GJ +
= 8GJ + (3/5)
3. uranium fuel cell and some algebra
+ 19 = 10
22 = 10 ( 8GJ + (3/5) )
22 = 80GJ + 6
16 = 80GJ
= 5GJ
∴ = 15GJ
4. uranium ore
10 = .007 + .993
∴ = 507MJ

(C) collary
to put in perspective,

= 63.375
= 20.28
= 2.253
= 9min 23sec *
= 14.1sec * a set of 1 : 20 : 40
= 3hr 21min *
= 8min 3sec * a set of 1 : 25 : 21
= 1min * 200 ( sized)

and these numbers can be multiplied by neighbour bonus.
eg: a moderate base is powered by 25 solar grid with 5000 . a patch of uranium ore near starting area has average of 50k . if this base remove solar and switch to 2x2 with x2 neighbour bonus (x3 total), how long can the ore patch sustain the base?

(50k ore * 507MJ/ore * 3)/(5000 solar * 42kW/solar) = 100.6hr

edit: 10 ore to process instead of 1

[Shokubai]

My last few games (playing Deathworld/RailWorld/ Normal) simulatiously.

I haven't built solar at all. This is great info.

[AndrewIRL]

Nice post, I like all the little inline icons.

Did you account for the energy cost of running the centrifuges or is it negligible?

[pichutarius]

@andrew, glad u like it. all the photos are from wiki (should something happen to the image link, this post will become a graveyard of dead link).
as for energy cost, by including crafting time into the equation, we got
= 15 GJ + 20 s
= 5 GJ - 10 s
= 5.07 GJ - 19.79 s

centrifuges has 350kW but craft at 0.75 speed, so this result in decreased fuel value of 350kW * 19.79 s / 0.75 = 9.235 MJ, which is 3 order of magnitude smaller than 5.07GJ, not to mention some process is done with assembler which cost less energy.

[Aeternus]

If energy savings is a priority keep in mind that you can put 2 Efficiency 2 modules in the Kovarex and Spent Fuel Reprocessing centrifuges. Probably more energy efficient to use Productivity Module 3's in the Fuel Cell assemblers and the Uranium Refining centrifuges - you get more fuel out of each uranium too that way. A lot more. Not sure if Uranium mines should get Productivity modules or Efficiency modules... I'm thinking 1 Productivity 3, 2 Efficiency 3's, or full Productivity. With so little fuel needed anyway, speed modules are likely overkill, unless you want to massproduce uranium ammo or nukes.

[AndrewIRL]

= .007 + .993
∴ = 5.07GJ

This part looks ... not quite right. It takes 10 ore being processed to yield one U238 or U235, not 1 ore.

10 + 10 → 1 + 1

Ref: https://wiki.factorio.com/Uranium_processing

∴ = 0.507GJ

[kinnom]

= .007 + .993
∴ = 5.07GJ

This part looks ... not quite right. It takes 10 ore being processed to yield one U238 or U235, not 1 ore.

10 + 10 → 1 + 1

Ref: https://wiki.factorio.com/Uranium_processing

∴ = 0.507GJ

The wiki is wrong. The recipe has a 99.3% chance to give you uranium 238, and 0.7% chance to give you uranium 235.

[Adeon Hawkwood]

The wiki is wrong. The recipe has a 99.3% chance to give you uranium 238, and 0.7% chance to give you uranium 235.

The bit about ten ore being required is correct however.

[pichutarius]

oh gosh, what a mistake! now the numbers should divide by 10... what a bummer

well i edit the numbers. now it doesnt look as pretty... thanks for pointing out the mistake tho.

edit:
@andrew, as for the energy cost, both fuel value and "crafting time" is divided by 10, so the ratio stays the same. (unless i make another stupid mistake)
= 15 GJ + 20 s
= 5 GJ - 10 s
= 507 MJ - 1.979 s

where 1.979s translate to < .924 MJ. when u include neighbour bonus, its pretty safe to say energy cost is negligible.

[AndrewIRL]

@andrew, as for the energy cost, both fuel value and "crafting time" is divided by 10, so the ratio stays the same.

The main effect is dividing the time, the end result of all your math, by 10. Your previous operational hours made Nuclear seem wildly OP. Now it merely seems regular OP!

a patch of uranium ore near starting area has average of 50k .

Next problem! I'm not sure 50K ore is going to get you started with Kovarex. You need 40 U235 to get it running.

40 * 10 / 0.007 = 57K ore

You might get lucky and score enough or you might only end up with 35 U235. I'd suggest that a player should find at least 60K or ore before getting started with Nuclear power.

Your startup mining drill electricity costs will be 90kW*57000/0.525 = 9.77GJ - ok this is also negligible if you get Kovarex started.

[milo christiansen]

This is really good info!

I would hate to have to work that out myself...