Line loss

An add-on for Power Overload (Factorio 2.1).
Power is lost along the wires between transformers: the farther it travels and the thinner the
poles carrying it, the more is lost. Transformers waste a little of what passes through them, plus
a small constant core loss. Every loss is burned by a hidden consumer, so it appears in the electric
network statistics and loads your power plants like any other demand.

Requirements and setup

• Factorio 2.1 and Power Overload 2.3.3 or later.
• Set Power Overload's Transformer efficiency map setting to 1 (100%). This mod charges
  transformer inefficiency itself, at its own efficiency setting. If Power Overload's is lower, this
  mod's efficiency is ignored (so it is never charged twice) and a one-time warning is shown.

How it works (short version)

• Each pole type has a line resistance (shown in its tooltip): small poles about 5.5 times a big
  pole, huge poles about a third.
• For each transformer the mod measures the resistance-weighted distance along the wires to what it
  feeds. Its line loss is 0.025% per tile of that distance, averaged over its consumers by the
  power each draws, and capped at 95% per route.
• A transformer fed directly by generators also pays for the wires to them: each pole is weighted by
  the rated output of the generators next to it, so far-away generators cost more. When several
  transformers draw from the same generators, they are paired like any other sources and consumers.
• Losses are burned by hidden consumers per transformer: Line loss on its downstream network
  (and on its upstream network when that is a generator network), and Transf. ineff.
  (inefficiency plus core loss) on its upstream network.

The details, with a worked example, are in FAQs.

Interface

• Hover a transformer: the power it draws and the upstream line loss.
• Transformer panel: upstream line loss (of the power arriving at it), downstream line loss (on the network it feeds, with distances and power lost),
  transformer inefficiency, core loss, power drawn and output.
• Grid diagram (shortcut bar, map view): a line for each route between transformers, wider
  with more power and coloured by its loss, labelled with power and loss; receiving transformers are marked with a diamond.
• Grid power panel: power generated, reaching consumers and lost, averaged over 5 s, and the 5 routes losing the most power.
• Heatmap (shortcut bar, map view): every pole coloured by the line loss of the power reaching
  it from its nearest transformer, from green (under 0.5%) to dark red (50% and above), to find the
  stretches of poles that cost the most.
• Power lost per pole (shortcut bar, map view): a dot on every pole sized and coloured by the power lost delivering load to machines in the pole's supply area. With "weight machines by their live load" on, it follows where the machines are and what they draw; otherwise machine load counts as spread evenly across the network.

Settings (map)

Gameplay

• Carry power far on big or huge poles and step down close to the factory; long runs of small poles
  are expensive.
• Feed large networks from several sides.
• Every transformer stage costs its inefficiency, and every switched-on transformer its core loss:
  do not stack or spam them without reason.
• Use the heatmap and the worst-routes list to see where an upgrade saves the most.

Performance

"Weight machines by their live load" adds an entity search per pole whenever a network is searched
again, and it searches a network again whenever an electric machine is built or removed on it, so
building large blueprints costs extra script time while bots work.

Distances are searched one transformer at a time. A search runs when its network changes (a pole
built or removed, networks merged or split, a transformer added or removed) at up to 100 poles per
tick, and a slow background pass (10 poles per tick) catches changes no event reports, such as a
wire added inside a network. Power is measured once a second from network statistics and smoothed;
the burns set from it apply from the next tick, so losses follow load changes within a few seconds
(and a transformer hands on the energy it draws one tick later, as in Power Overload). The
"nearest first" balancing runs every 5 s per network, spread out so networks do not all update on
the same tick. To check the cost on your save, enable show-time-usage in the debug settings (F4).

Notes

• Power Overload's transformer data is private, so each transformer's power is read from network
  statistics; when several feed one network the total is split by Power Overload's buffer sizes.
• A wire added or removed inside a network without merging or splitting it is picked up by the
  background pass, so it can take a while on very large bases.
• By default machines count as spread evenly over poles, so a heavy machine cluster costs the same as
  a light one on the same poles. Turn on "weight machines by their live load" to locate them, or put a
  transformer in front of a big remote load to have it measured exactly.
• Not charged: machines powered directly by a generator network (no transformer in between), and
  generators wired into a network that a transformer also feeds.

Credits and licence

• Built on Power Overload by Xorimuth (Tom Burrows),
  which it requires. Parts of this mod are adapted from Power Overload's code, and it uses Power
  Overload's shared.lua and settings at runtime.
• MIT licence. LICENCE.txt keeps Power Overload's copyright notice (Copyright (c) 2022 Tom Burrows)
  together with this add-on's (Copyright (c) 2026 Antonio Carnevali).