Do I need Space Age?
No. The mod loads and plays on base Factorio 2.1. Space Age adds the holmium, foundation, solar, accumulator, and fusion tiers on top; without it the ladders stop earlier: boilers and steam engines at rubber-lined, steam turbines and heat exchangers at reinforced, heat pipes and nuclear reactors at mk2. Solar, accumulators, and fusion are Space Age only.
Can I add this to a save already in progress?
Yes, and no migration is needed. Be aware that it changes how nuclear heat behaves, so an existing reactor block will not perform the way it did before — see the next question.
My nuclear power dropped after installing or updating. What happened?
Heat now loses temperature as it travels along a heat pipe, and loses more the harder the run is working. The far end of a long exchanger run arrives cooler than it used to, so those exchangers make cooler steam and their turbines produce less. Nothing errors and nothing stops.
The fix is almost always to split exchangers across several shorter runs rather than one long one. Load costs more temperature than length does, so many short spokes beat a few long ones for the same tile count.
My heat network will not go above a certain temperature.
Look for a heat pipe you forgot to upgrade. Each tier carries heat only up to its own ceiling — 625, 812.5, 1000, and 1250 degrees — and a heat pipe is a node in the network like any other, so the lowest tier anywhere in a run caps the entire run. One leftover tier 1 pipe holds an mk3 network at 625, well under that tier's 800 optimal.
There is no error for this. The tiers are tinted so the odd one out can be spotted, and every heat pipe states its ceiling in its tooltip.
Why is my steam cooler than the exchanger's optimal temperature?
Heat exchangers work from 300 degrees up to their optimal rather than switching on at a single point. Below optimal they still run, producing steam at whatever temperature the heat network is actually at, and turbines scale with it. That is deliberate: a network that dips loses part of its output instead of all of it.
Do I have to rebuild my reactor blocks?
No. Reactors placed flush against each other are worth exactly what they were before. The bonus is now paid per aligned heat connection rather than per neighbour, which only changes things if reactors are offset — and an offset block now earns a partial bonus where vanilla gave it nothing.
Why is my steam turbine producing less than 5.82 MW?
The vanilla steam turbine is 5.56 MW here, so that one heat exchanger feeds exactly 1.8 turbines at every tier. The ratio learned at the first tier then stays true all the way up.
Why do I suddenly need pumps?
Only with Advanced Fluid Infrastructure installed. Every building in this mod is then held to a 24 tile pipeline extent regardless of tier, so upgrading a building buys output rather than reach and pumps stay part of the layout. Without that mod, pipeline extent is untouched.
Is the top tier supposed to be less efficient?
Yes. Measured on a 2x2 block at each tier, a well-built steel block runs at 100% of rated turbine output and an mk4 block at about 88%. Higher tiers produce far more power, but reach less far and demand more care in placement. A bigger reactor is meant to be a harder problem, not just a bigger number.
Does it conflict with other power mods?
It changes a few base game prototypes deliberately: the vanilla heat exchanger and heat pipe take this mod's tier 1 values, the vanilla steam turbine produces 5.56 MW, and every reactor tier has the engine's own neighbour bonus switched off. The one that reaches outside this mod is the vanilla heat pipe, which now carries heat to a lower ceiling and loses more per tile, so anything else built on base game heat pipes is affected — Space Age heating towers included. Higher pipe tiers restore and exceed the vanilla ceiling.