Cool Steam Vent

A Cool Steam Vent is a geyser that periodically erupts 110 °C steam. The vent is a renewable source of hot water after the steam is condensed, but its output is not hot enough to feed a Steam Turbine directly without extra heating, since the turbine requires steam above 125 °C. Cool Steam Vents can be found in Marsh Biomes and Jungle Biomes, and both biome types are guaranteed to contain one exposed vent.

Because the steam leaves the vent below Steam Turbine operating temperature, the usual first step is to condense it into water. Steam condenses at 97.4 °C, so only 13.6 degrees of cooling are needed. That makes Cool Steam Vent output easier to handle than normal steam, but it also means that if you do not need cool water, a highly optimized cooling loop is unnecessary.

Common ways to make use of the vent include:

• Filling the space behind the vent with Tempshift Plates connected to surrounding walls to increase heat transfer and slowly dump heat into nearby tiles.
• Building a sealed chamber next to the steam room and using Wheezeworts in a hydrogen-filled compartment, with Metal Tiles as a shared wall to pull heat toward the Wheezeworts.
• Running a cooled gas or liquid pipe past the steam output, such as hydrogen cooled by a Thermo Regulator, if that cooling loop already exists in the colony.
• Using the vent as a renewable source of near-boiling water for buildings that tolerate high temperatures.

Several buildings can accept the vent’s hot water output without issue, including Electrolyzers, Research stations, Microbe Mushers, Toilets, Sinks, and Showers. If the water needs to be used for crop irrigation, or if it must be cooled further for something like Bristle Blossoms or Sleet Wheat, a dedicated cooling setup is preferable.

A Steam Turbine cannot be driven directly by the vent unless the steam is heated first. One common solution is to pair the vent with a Thermo Aquatuner and Steam Turbine loop. With Super Coolant, this can be balanced into a self-running setup, although it does not produce much net power unless Engie's Tune-Up is applied. With Engie's Tune-Up, the same arrangement can generate substantial power while also providing strong cooling. A less efficient version using water as the Aquatuner coolant can serve as a renewable cold-water source in the mid-game without requiring space materials.

Only one Steam Turbine input needs to reach 125 °C for the turbine to activate, which can reduce the power cost of the cooling loop. Careful tuning can sometimes make the system slightly power positive, but that setup is difficult to keep stable, so other power sources are still recommended for load balancing. Another approach is to use a steel Thermo Aquatuner to cool the Steam Turbine’s output water and dump that heat back into the steam from the vent, though the Turbine itself will accumulate heat over time and may need additional cooling around its body.

A Geotuner can also be attached to the vent. This increases the steam temperature above the Turbine threshold and increases the amount of steam produced, but it adds a small Bleach upkeep that must be supplied over time. One practical note is that reducing insulation thickness around the vent can expose Duplicants to scalding in hot environments rather than protecting them.