Water supply for nuclear reactors

Don't know how to use a machine? Looking for efficient setups? Stuck in a mission?
Post Reply
Amarula
Fast Inserter
Fast Inserter
Posts: 187
Joined: Fri Apr 27, 2018 1:29 pm
Contact:

Water supply for nuclear reactors

Post by Amarula » Fri Nov 29, 2019 3:09 pm

How do you set up a reactor to get enough water to keep producing steam?

According to the wiki https://wiki.factorio.com/Power_product ... lear_power, the 'simple ratio' is 1 off-shore pump to 12 heat exchangers to 20 steam turbines. That is the ratio I have for my reactors. Also according to the wiki https://wiki.factorio.com/Fluid_system, water flow capacity drops to 1200/sec at 17 pipes. I have pumps after 5 underground pipes, equivalent to 10 pipes, which I thought should be more than enough to keep the water flowing.
In theory, there is no difference between theory and practice. In practice, there is. Yogi Berra
I ran low on power yesterday, and threw in another reactor complex to compensate. And hey I was still low. So I spent some time watching one of my reactors operating, and observed the following:
-To start, the water pipes and heat exchangers are full of water; the heat pipes are cool and the exchangers are not operating 'no fuel'.
-As the reactor produces heat, the heat pipes and heat exchangers increase in temperature and one by one, from closest to the reactor to furthest away, the heat exchangers start producing steam. For a few seconds after the 12th exchanger starts operating, steam production is in full swing (103/103 steam output).
-As water is consumed to produce steam, the water supply drops until the heat exchangers one by one stop producing the full amount of steam because they are out of water. One by one, they drop to 66/103 steam per second.
-Once the nuclear fuel cell is consumed, the heat pipes slowly cool down (I have delay on refueling until steam drops to a certain level). One by one, from furthest away to closest, the heat exchangers top working 'no fuel'. Slowly the pipes and heat exchangers refill with water.
And then the cycle repeats.

So even though I have a total of 1700 steam turbines, for a theoretical max output of 9.89GW, in practice it only produces 66/103 of that, so I start running out of power for my base around 6.3GW.

I am going to experiment with a few options today and I will report on the results:
-adding a second off-shore pump to start off with twice as much water (in theory);
-putting in more pumps, say one pump for every underground pipe;
-putting in a complete second line from off-shore pump to heat exchangers with a pump every 5 underground pipes.

Any experiences/suggestions/comments are welcome.

azesmbog
Inserter
Inserter
Posts: 44
Joined: Mon Jan 28, 2019 12:05 pm
Contact:

Re: Water supply for nuclear reactors

Post by azesmbog » Fri Nov 29, 2019 4:19 pm

“A theory without practice is dead, practice without a theory is blind”, this quote is attributed to commander Alexander Suvorov.
theory of wiki.factorio:
2x4 core, 8 reactors, 112 Exchangers, 193 Turbines, 1120MW
In practice, I have this:
2x4 core, 8 reactors, 136 Exchangers, 204 Turbines

You can add another 12 turbines to the current design, but there is no sense anymore, then even at full 60/60 load there is not enough steam. And for this amount - enough.
Offshore pump -14, there are no additional pumps for water, only for steam

mrvn
Smart Inserter
Smart Inserter
Posts: 3892
Joined: Mon Sep 05, 2016 9:10 am
Contact:

Re: Water supply for nuclear reactors

Post by mrvn » Fri Nov 29, 2019 4:41 pm

Heat exchangers are pipes too. So you have 10 + 12 = 22 pipes. Or so. Heat exchangers have different dynamics to actual pipes. The flow between pipes and heat exchangers is also different to pump to heat exchangers.

Same goes for steam and steam turbines. It sounds like you have reactors, heat exchangers, steam turbines and only then water pipes. Why not put the water pipes between the reactor and heat exchangers. Or heat exchangers and steam turbines. No underground pipes for water used at all, athough the later needs some for steam. You can even do both, offshore pumps on both sides of the heat exchangers.

If recommend having a pump for the steam at the end of the heat exchangers. You have a lot of pipes to collect al the steam and you want to maximise the height differential in that pipe. With offshore pumps between the heat exchangers and steam turbines (and therefore underground pipes for steam I recommend one on each side of the underground pipe.

User avatar
eradicator
Smart Inserter
Smart Inserter
Posts: 3769
Joined: Tue Jul 12, 2016 9:03 am
Contact:

Re: Water supply for nuclear reactors

Post by eradicator » Fri Nov 29, 2019 4:43 pm

Amarula wrote:
Fri Nov 29, 2019 3:09 pm
Also according to the wiki https://wiki.factorio.com/Fluid_system, water flow capacity drops to 1200/sec at 17 pipes.
Fluid pressure drops on every transfer. Pipes are just the worst, but boilers-to-boiler etc doesn't preserve full pressure.
Author of: Hand Crank Generator, Screenshot Hotkey 2.0
Mod support languages: 日本語, Deutsch, English
My code in the post above is dedicated to the public domain under CC0.

User avatar
disentius
Filter Inserter
Filter Inserter
Posts: 313
Joined: Fri May 12, 2017 3:17 pm
Contact:

Re: Water supply for nuclear reactors

Post by disentius » Fri Nov 29, 2019 9:15 pm

can you post a screenshot/blueprint? makes troubleshooting easier.
Recent reactor discussion with examples:
viewtopic.php?f=5&t=78025

leitk
Long Handed Inserter
Long Handed Inserter
Posts: 94
Joined: Wed Jun 21, 2017 7:20 pm
Contact:

Re: Water supply for nuclear reactors

Post by leitk » Mon Dec 02, 2019 4:29 am

Build the reactor over a lake, with careful placement of landfill you can have pumps directly feeding each end of the heat exchanger line.

Honktown
Fast Inserter
Fast Inserter
Posts: 237
Joined: Thu Oct 03, 2019 7:10 am
Contact:

Re: Water supply for nuclear reactors

Post by Honktown » Mon Dec 02, 2019 1:56 pm

9.89 gigawatts is a lot. In a vanilla game that's.... what, 1k science a minute? Someone already mentioned the normal "build on a lake" strategy

If you want to be a cheating bastard about it, I ported a mod from .16:

https://mods.factorio.com/mod/AdvancedNuclear3

I guess experience wise, pipe flow is one of the most aggressive things about nuclear reactors. I could never keep the flow at max, unless I overbuilt and tapped/replenished middles of lines and stuff.

Amarula
Fast Inserter
Fast Inserter
Posts: 187
Joined: Fri Apr 27, 2018 1:29 pm
Contact:

Re: Water supply for nuclear reactors

Post by Amarula » Mon Dec 02, 2019 3:51 pm

leitk wrote:
Mon Dec 02, 2019 4:29 am
Build the reactor over a lake, with careful placement of landfill you can have pumps directly feeding each end of the heat exchanger line.
This.

I am... speechless.

Post Reply

Return to “Gameplay Help”

Who is online

Users browsing this forum: No registered users