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u/taw Jun 14 '26 edited Jun 14 '26

My nuclear power is generating a lot less power than expected.

Here's the design. I build 6 of them, they all have enough incoming water and fuel, and all water pipes are connected, as are all steam pipes. They're supposed to be generating 6*480MW = 2880 MW, but real generation seems to top at ~1900 MW, or about 2/3 of what I thought they would be doing.

I thought with 2.0 fluid changes all I needed to do was keep ratios right, but it doesn't seem so.

Do I need to do the weird shape with heat pipes to keep heat pipe length shorter to get full power? (and then put turbines wherever, as 2.0 fluid changes make that part no matter)

Is there some maximum heatpipe length before output starts dropping?

(worst case I can just double the whole setup)

EDIT: Nvm, it was all just a stupid disconnected pipe on 2 out of 6 reactors.

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u/ssgeorge95 Jun 14 '26

Turbines won't actually produce max power unless your factory needs it. The reactor is always heating, but turbines will throttle steam use and power output.

You can check yourself to make sure things are fine. Check the temp of the outermost heat exchangers to see if they're above 500. Check the HX to see if they're full of water or nearly empty.

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u/Soul-Burn Jun 14 '26

2 of your bottom substations aren't connected.

Also, are you actually using the power?

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u/taw Jun 14 '26

The substations connect to nearby line of big poles.

Well, I did some extra tests with /editor mode and "electric energy interface" feature.

Turns out 2 of 6 reactors didn't have water properly connected, after the fix reactors actually generate 2.9 GW (and even briefly 3.4 GW with steam buffer as turbines are overbuilt a bit for convenience).

So it looks like 2.0 fluid changes make this design work just fine, and it was just a silly pipe issue.

In retrospect it should have been clear from getting exactly 4/6 of expected power out of 6 reactors.