# Consequence Systems — Heat & Pollution

NeroTech couples throughput to two consequence axes so automation has trade-offs: **heat** (local, per
machine) and **pollution** (regional, periodic). Both are server-authoritative and fully server-config
tunable (`config/nerotech.properties`, managed by Core).

## Heat

Every machine carries a **heat** value (shown as the red gauge on the right of its GUI):

- **Accumulates** while the machine works — generators while burning, processors each work tick.
- **Dissipates** passively every tick, and **faster when adjacent to a coolant block** (water, ice,
  packed/blue ice, snow block, powder snow) — the simplest cooling.
- **Throttles**: once heat reaches the threshold, a processing machine **stalls** until it cools back
  down. This is the counter-pressure that stops players trivially overclocking everything with Speed
  modules.

Heat is per-block-entity (no global scan) and persists across relog. Tuning keys: `heatCapacity`,
`heatPerOperation`, `heatDissipationPerTick`, `heatThrottleThreshold`.

## Pollution

Industrial activity emits **pollution**, aggregated **regionally** (a coarse 64×64-block grid), never
per-block-per-tick:

- Running machines add to their region's total on a **batched interval** (spread across ticks per
  machine), so there is no per-tick hotspot. Generators and processors pollute; the **Solar Array is
  clean** (no heat, no pollution).
- A **periodic server sweep** decays every region's pollution and prunes emptied regions — it iterates
  a small map, not the world.

Tuning keys: `pollutionPerOperation`, `pollutionContributionIntervalTicks`,
`pollutionDecayIntervalTicks`, `pollutionDecayAmount`.

### Per-player attribution & privacy (POPIA / GDPR)

By **default, pollution is aggregate-only** — no player data is stored. A server may opt in with
`pollutionPerPlayerAttribution=true`, which attributes pollution to the **placing player's UUID**.
When (and only when) this is enabled:

- Only **UUIDs** are stored (never names, IPs, chat, or location) — data minimisation.
- Attribution rows are **retention-pruned** after `pollutionAttributionRetentionDays`.
- A **`PlayerDataEraser`** is registered with Core's shared `data.PlayerDataErasure`, so a single
  erase request (or Core's inactivity sweep) purges a player's NeroTech attribution alongside every
  other Nero mod.

## See also

- [Tier-1 Machines](Machines.md)
- [Home](Home.md)