Geothermal Power Station

The Geothermal Power Station is a power facility that generates electricity continuously from the heat of lava or from a borehole left behind when a Dark Fog Planetary Base is destroyed. It is a fully renewable building with no fuel consumption or maintenance, but its placement is severely restricted: it can only be built directly on top of lava or on a Core Driller hole.

When built on lava, its output depends on how much lava surrounds it, with the best performance coming from the center of a magma pool. In practice, this usually means a modest but reliable power source rather than a large-scale power plant. Its output on lava can rise to around 120–130% efficiency, but it also drops if nearby terrain is filled in, with a lower bound of about 10%. Like Wind Turbines, it cannot be densely packed, and it needs roughly 12 m of spacing, though the exact distance depends on placement. Because of this, large geothermal farms on lava are possible but tedious to lay out, and Blueprints are not especially convenient for mass deployment.

The building becomes much more valuable on planets affected by the Dark Fog. When the Dark Fog destroys one of its own Planetary Bases, the resulting borehole can be used as a Geothermal Power Station site. These holes can produce extremely high output, typically around 300–600% efficiency and 14.4–28.8 MW of power, depending on the level of the destroyed base. Lower-level bases yield roughly the 300% range, while higher-level bases can reach well above 500%. For players who can handle Dark Fog pressure, deliberately destroying Planetary Bases is one of the easiest ways to create a strong early-game power spike.

A few practical points make the building more useful:

• On lava, place it as close to the center of the magma pool as possible for maximum efficiency.
• On Dark Fog boreholes, the destroyed base’s level directly affects power output.
• The Dark Fog’s relay landings cannot be forced to create a borehole on demand, but their target areas can be influenced by leaving gaps in planetary shielding or covering much of the surface with mass-produced buildings such as Wind Turbines.
• Geothermal Power Stations can be used to export power with Energy Exchangers; about 10 stations at 120% efficiency are enough to fully supply one Energy Exchanger.

Because it is free power once placed, the Geothermal Power Station is especially valuable for remote outposts and early expansion, particularly on Lava planets. In the late game, however, lava-based geothermal power often becomes too limited to support large industrial demands on its own unless many stations are built.