Energy Systems - Heliomance/Uncharted-Horizons GitHub Wiki

_{Focus Areas · Design document §3}

Available from: WM01 (Canal) + MC03 (Gearing), or TH01 (Laws of Thermodynamics) + EL03 (Electromagnetism)

Also reachable in this focus (dual-path; home focus in parentheses): Water Mill (WM05, from Water Management); Windmill (MC04, from Mechanics); Stirling Engine Mastery (TH08, from Thermodynamics). The Water Mill is the first mechanical power source beyond muscle.

22 breakthroughs — CORE 1 · STANDARD 15 · UNCOMMON 4 · RARE 2 — Modern – Space

Builds on: Observation (1) · Farming (1) · Mining (3) · Metallurgy (1) · Mechanics (2) · Thermodynamics (11) · Chemistry (2) · Optics (1) · Electricity (4) · Electronics (1) · Computing (1) · Nuclear Physics (3) · Quintessic Physics (4) · Quantum Physics (3) · Rocketry (1)

Leads into: Trade (4) · Nuclear Physics (4) · Space Engineering (1)

_{The numbers count prerequisite links between this focus and the other. How to read the tables.}

One grid plant per city — and never locked into the first. Every grid plant carries the tag unique ⟨Power Plant⟩. Unciv files every unique a building has, recognised or not, under its text (UniqueMap.addUnique), and Building.matchesFilter matches a building by any exact unique it has, so [Power Plant] names the whole group. Each plant also carries Remove [{Power Plant} {non-[its own name]}] [in this city], which fires when it is completed (CityConstructions.addBuilding → triggerNewBuildingUniques): building a new plant retires the old one, which keeps the city powered until its replacement is ready. So a city holds one plant at a time, as in Civ V, but a Generating Station never bars the way to a Fusion Plant. The canonical Nuclear and Solar Plants join the group through the ruleset derivation, generalising their pairwise exclusion; the Hydro Plant stays outside it, as canonically it stands beside one. (Until v3.76 the group was a placeholder building that every plant declared it replaces, with Only available <in cities without a [Power Plant]> — which blocked every later plant, and which Unciv's capture swap, following replaces, would have turned into the stat-less placeholder.)

flowchart LR
  n_ES03["ES03 Coal Power Plant"]:::STANDARD
  n_ES03_W["ES03-W Biomass Power Plant"]:::STANDARD
  n_ES05["ES05 Oil Power Plant"]:::STANDARD
  n_ES06["ES06 Nuclear Fission Plant"]:::CORE
  n_ES14["ES14 Advanced Fission"]:::STANDARD
  n_ES07["ES07 Solar Panel"]:::STANDARD
  n_ES08["ES08 Fusion Reactor"]:::STANDARD
  n_ES09["ES09 Geothermal Power"]:::UNCOMMON
  n_ES10["ES10 Tidal Power"]:::UNCOMMON
  n_ES11["ES11 Beamed Power"]:::UNCOMMON
  n_ES12["ES12 Zero-Point Energy"]:::RARE
  n_ES13["ES13 Biomass/Biogas"]:::STANDARD
  n_ES05_W["ES05-W Alcohol/Biogas Power Plant"]:::STANDARD
  n_ES22["ES22 Smart Grid"]:::STANDARD
  n_ES17["ES17 Grid-Scale Storage"]:::STANDARD
  n_ES20["ES20 Continental Interconnects"]:::STANDARD
  n_ES21["ES21 Global Supergrid"]:::STANDARD
  n_ES19["ES19 Electrified Industry"]:::STANDARD
  n_ES18["ES18 Superconducting Energy Storage"]:::STANDARD
  n_QM_E07["QM-E07 Aether Tension Engine"]:::RARE
  n_ES15["ES15 Quintessic Power Plant"]:::STANDARD
  n_ES16["ES16 Caloric Engine Plant"]:::UNCOMMON
  n_ES13 -.-> n_ES05_W
  n_ES06 --> n_ES14
  n_ES22 --> n_ES17
  n_ES22 --> n_ES19
  n_ES22 --> n_ES20
  n_ES17 --> n_ES20
  n_ES20 --> n_ES21
  n_ES19 --> n_ES21
  classDef CORE fill:#dbeafe,stroke:#1d4ed8,color:#0b1b3b
  classDef STANDARD fill:#f1f5f9,stroke:#64748b,color:#0f172a
  classDef UNCOMMON fill:#dcfce7,stroke:#15803d,color:#052e16
  classDef RARE fill:#fef3c7,stroke:#b45309,color:#3b2005
  classDef UNIQUE fill:#fae8ff,stroke:#a21caf,color:#3b0a3f

_{Prerequisites within this focus. Box colour is the tier (blue CORE, grey STANDARD, green UNCOMMON, amber RARE, purple UNIQUE); dotted arrows are alternatives (“or”); a line can pass behind another box, so follow it from its start. 18 of these 22 breakthroughs also need breakthroughs from other foci, which the overview above lists.}

• Tier: STANDARD · Era: Modern
• Prerequisites: TH03 + ME08 (Blast Furnace — coal or charcoal)
• Unlocks: Coal Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 440/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨[-1 Happiness] [in this city]⟩ — the smoke; requires Coal; ⟨Remove [{Power Plant} {non-[Coal Plant]}] [in this city]⟩]. It burns Coal from pits or Charcoal Kilns alike, so it exists in every world.

• Tier: STANDARD · Era: Modern
• Prerequisites: TH03 + MI13 (Wood Gas) + FA03 (Selective Breeding)
• Unlocks: Biomass Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 440/2; requires a Factory in this city; +1 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨Remove [{Power Plant} {non-[Biomass Plant]}] [in this city]⟩] — renewable, cleaner, weaker. Competing Solution (§1.2): the alternative to Coal Power Plant (ES03), detour margin ×1.5 while Coal Power Plant exists in this world; if Coal Power Plant is discovered first this is never developed, and if it arrives later this persists — it needs no Coal and makes no smoke, and gives up a point of Production for it. A power station costs what its peers do, whatever it burns. Also discoverable through Farming.

• Tier: STANDARD · Era: Modern
• Prerequisites: TH03 + (MI07 or MC09) — petroleum, or the engine that distils it
• Unlocks: Oil Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 440/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨[-1 Happiness] [in this city]⟩; requires Oil; ⟨Remove [{Power Plant} {non-[Oil Plant]}] [in this city]⟩]. It burns Oil from wells or Distillery Fuel Depots alike, so it exists in every world.

• Tier: STANDARD · Era: Modern
• Prerequisites: (MC09 (Internal Combustion Engine) or ES13 (Biomass/Biogas)) + TH03
• Unlocks: Bio-Fuel Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 440/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨[-2 Food] [in this city]⟩ — fuel grown on land that could have fed the city; ⟨Remove [{Power Plant} {non-[Bio-Fuel Plant]}] [in this city]⟩]. Competing Solution (§1.2): the alternative to Oil Power Plant (ES05), detour margin ×1.5 while Oil Power Plant exists in this world; if Oil Power Plant is discovered first this is never developed, and if it arrives later this persists — it needs no Oil.

• Tier: CORE · Era: Atomic
• Prerequisites: NP03 + TH03 (Turbine Design — the heat exchanger)
• Unlocks: Nuclear Plant (canonical: +5 Production, Production +15%, maintenance 3, requires Uranium) — a grid plant: the ruleset derivation replaces its canonical <in cities without a [Solar Plant]> with ⟨Power Plant⟩ (tag) and ⟨Remove [{Power Plant} {non-[Nuclear Plant]}] [in this city]⟩.
• Leads to: NP15 Superconducting Storage Rings, NP-F01 Advanced Fuel Cycles, ES14 Advanced Fission

• Tier: STANDARD · Era: Atomic
• Prerequisites: (QP02 Quantum Mechanics, or QM-E14 Limiting Fineness) + EN06 (Semiconductor Mastery)
• Unlocks: Solar Plant (canonical: +5 Production, Production +15%, maintenance 3, must be next to Desert) — a grid plant: the ruleset derivation replaces its canonical <in cities without a [Nuclear Plant]> with ⟨Power Plant⟩ (tag) and ⟨Remove [{Power Plant} {non-[Solar Plant]}] [in this city]⟩. In elemental worlds the panel works by resonance rather than the photovoltaic effect; it is still a solar panel. (v3.28's plan to make it consume Rare Earths is withdrawn to keep the canonical plant familiar; Rare Earths keeps five consumers.)
• Notes: In elemental worlds the panel works by resonance — sunlight's overtones drive electric fire out of a tuned surface — rather than by the photovoltaic effect. It is still a solar panel: same farm, same sun, same name.
• Leads to: SE09 Advanced Solar Power

• Tier: STANDARD · Era: Space
• Prerequisites: NP04 + EL11 + TH03 (Turbine Design — the heat exchanger) — cost ×2.5
• Unlocks: Fusion Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 1125/6; requires a Factory in this city; +8 Production; ⟨[+15]% [Production] [in this city]⟩; no fuel; ⟨Remove [{Power Plant} {non-[Fusion Plant]}] [in this city]⟩] — the Re-Tempering Reactor's stats (QM-E05), so the endgame plants match. Requires NP04 — unavailable in FQ2-Impossible worlds.
• Notes: W18 — Pool; power for Warp (atomic worlds).
• Leads to: TR15 Post-Scarcity Economics, NP15 Superconducting Storage Rings

• Tier: UNCOMMON · Era: Modern
• Prerequisites: MI05 + TH01
• Unlocks: Geothermal Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 375/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨[+1 Production] from [Volcanic] tiles [in this city]⟩; ⟨Remove [{Power Plant} {non-[Geothermal Plant]}] [in this city]⟩] — the earth's own heat, strongest near the vents.

• Tier: UNCOMMON · Era: Atomic
• Prerequisites: O04 (Tidal Patterns) + TH03
• Unlocks: Tidal Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 310/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; ⟨Must be next to [Coast]⟩; ⟨Remove [{Power Plant} {non-[Tidal Plant]}] [in this city]⟩] — predictable, clean, coastal.

• Tier: UNCOMMON · Era: Space
• Prerequisites: OP07 (Laser) + RK05 — cost ×2.5
• Unlocks: ⟨[+3 Production] [in all cities] <in cities without a [Power Plant]>⟩ — power beamed from orbit to every town that has no plant of its own.
• Notes: W18 — Pool.

• Tier: RARE · Era: Space
• Prerequisites: QP12 (Casimir Amplification) + QP08 — cost ×4
• Unlocks: ⟨[+1 Production] from all [Power Plant] buildings⟩ — the vacuum hums faintly in every plant. Zero-Point Reactorⁿ [world wonder; 1500; ⟨[+15]% [Production] [in all cities]⟩; ⟨[+2 Production] from all [Power Plant] buildings⟩ — every plant in the empire runs on the vacuum's hum]. The atomic counterpart of the Aether Tension Engine (QM-E07). RARE.
• Notes: W18 — Capstone B, rare (atomic worlds).
• Leads to: TR15 Post-Scarcity Economics

• Tier: STANDARD · Era: Modern
• Prerequisites: CH04 (Distillation) + CH07 (Organic Chemistry)
• Unlocks: Biogas Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 440/2; requires a Factory in this city; +1 Production; ⟨[+5]% [Production] [in this city]⟩; no fuel; ⟨Remove [{Power Plant} {non-[Biogas Plant]}] [in this city]⟩]; Recycling Center (canonical — provides Aluminum). Waste into power, in any terrain — it needs no fuel and gives up a point of Production for it. Also discoverable through Chemistry or Farming.
• Leads to: ES05-W Alcohol/Biogas Power Plant

• Tier: STANDARD · Era: Space
• Prerequisites: NP-F01 + ES06 — cost ×2.5
• Unlocks: Advanced Fission Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 1125/6; requires a Factory in this city; +6 Production; ⟨[+15]% [Production] [in this city]⟩; requires Uranium; ⟨Remove [{Power Plant} {non-[Advanced Fission Plant]}] [in this city]⟩]. Competing Solution (§1.2): the alternative to Fusion Reactor (ES08), detour margin ×1.5 while Fusion Reactor exists in this world; if Fusion Reactor is discovered first this is never developed, and if it arrives later this persists — it is part of the deep fission chain.; primary in FQ2-Impossible worlds.
• Notes: W18 — Pool; power for Warp (atomic worlds). Deep fission path energy.
• Leads to: TR15 Post-Scarcity Economics, NP15 Superconducting Storage Rings

• Tier: STANDARD · Era: Space
• Prerequisites: EL07 + CP04 — cost ×2.5
• Unlocks: ⟨[+10]% [Production] [in all cities] <in cities connected to the capital>⟩ — connection to the capital gates the bonus.
• Notes: W18 — Entry: opens the pool.
• Leads to: ES17 Grid-Scale Storage, ES19 Electrified Industry, ES20 Continental Interconnects

• Tier: STANDARD · Era: Space
• Prerequisites: EL11 + EL07 — cost ×2.5
• Unlocks: ⟨[+25]% Production when constructing [Wonder] wonders⟩ — energy released in an instant: a warp bubble's need, and on the ground the heavy plant of megaprojects.
• Notes: W18 — Pool; Warp engineering (both ontologies).

• Tier: STANDARD · Era: Space
• Prerequisites: ES22 — cost ×2.5
• Unlocks: Storage Arrayⁿ [building; cost set at spec; needs a power plant in the city; +2 Production; ⟨[+10]% [Production] [in this city]⟩].
• Notes: W18 — Pool.
• Leads to: ES20 Continental Interconnects

• Tier: STANDARD · Era: Space
• Prerequisites: ES22 — cost ×2.5
• Unlocks: ⟨[+15]% Production when constructing [All] buildings⟩.
• Notes: W18 — Pool.
• Leads to: ES21 Global Supergrid

• Tier: STANDARD · Era: Space
• Prerequisites: ES22 + ES17 — cost ×2.5
• Unlocks: ⟨[-50]% maintenance cost for [Power Plant] buildings⟩.
• Notes: W18 — First step of capstone A.
• Leads to: ES21 Global Supergrid

• Tier: STANDARD · Era: Space
• Prerequisites: ES20 + ES19 — cost ×4
• Unlocks: ⟨[+15]% [Production] [in all cities]⟩.
• Notes: W18 — Capstone A (the reliable one).

• Tier: RARE · Era: Space
• Prerequisites: QM-E13 (Aetheric Vacuum) + QM-E27 (Plenum Gravitation) — cost ×4
• Unlocks: ⟨[+1 Production] from all [Power Plant] buildings⟩ — the medium hums faintly in every plant. Aether Tension Engineⁿ [world wonder; 1500; ⟨[+15]% [Production] [in all cities]⟩; ⟨Provides [2] [Aluminum]⟩; ⟨Provides [2] [Rare Earths]⟩ — power drawn from the medium at scale, and spent on making the rare common]. Frontier Question FQ4 (Vacuum Energy): where vacuum energy is extractable (~20% of worlds) it validates; otherwise it dead-ends with a clear negative report — "the medium's tension yields only traces" — exactly as Zero-Point Energy (ES12) does in atomic worlds. Substance: "Aether Tension Engine" — power drawn from the Aether's tension, the vacuum tap at power scale (Model I, §7); with power this abundant, re-tempering's loss stops mattering, and common substance is re-tempered into the rare metals. Process: "Still-Point Engine" — power drawn at the still point where the cycle turns (Model II, §7); so much flow drives Earth-patterns forward into Metal — Earth bears Metal — faster than any mine. The mirror of Zero-Point Energy (ES12), as its prerequisites are of ES12's (Casimir Effect Amplification and Quantum Gravity Theory).
• Notes: W18 — Capstone B, rare (elemental worlds) — moved here from Quintessic Physics. Power from the medium itself — where the medium allows it.
• Leads to: TR15 Post-Scarcity Economics

• Tier: STANDARD · Era: Atomic
• Prerequisites: QM-E02 (Bound-Energy Release) + TH03 (Turbine Design — the heat exchanger)
• Unlocks: Quintessic Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); 690/4; requires a Factory in this city; +3 Production; ⟨[+10]% [Production] [in this city]⟩; no fuel — bound energy from common matter; ⟨[+2 Production] [in this city] <when number of [Uranium] is more than [0]>⟩; ⟨[+5]% [Production] [in this city] <when number of [Uranium] is more than [0]>⟩ — Uranium, the richest feedstock, lifts it to the Nuclear Plant's own output; ⟨Remove [{Power Plant} {non-[Quintessic Plant]}] [in this city]⟩]. The elemental mirror of the Nuclear Plant. In Process worlds, where the plant runs by driving the destructive cycle, its name is the Overcycle Plant.
• Notes: Only in Elemental worlds (FQ9). Fills the ES06 niche.

• Tier: UNCOMMON · Era: Modern
• Prerequisites: TH11 (Caloric Storage) + TH03 (Turbine)
• Unlocks: Caloric Plantⁿ [a grid plant: ⟨Power Plant⟩ (tag); ⟨Costs [60] [Caloric]⟩ — bought with banked heat; 440/2; requires a Factory in this city; +2 Production; ⟨[+5]% [Production] [in this city]⟩; no fuel; ⟨Remove [{Power Plant} {non-[Caloric Plant]}] [in this city]⟩]. Caloric worlds only.
• Notes: Only in Caloric worlds. Heat as a bankable substance.