Steam Engine
There is a version of this article for the

SteamEngine
Steam Engine is an entry-level rocket engine. It must be fueled via pipe with steam derived from water (either from geysers or make your own). The engine can store up to 900 kg of steam. A lower limit can be set manually by a player.
The content's heat does not change, even when built within atmosphere, so there is no risk of steam condensing.
The engine efficiency is 20 km/kg of steam - up to a maximum of 18,000 km (900 kg steam). This does not take into account weight penalties (1 km lost per 1 kg mass up to 4000 kg, then the penalty increases exponentially).
The steam engine will limit you to the closest destinations until you can build more advanced engines.
It exhausts steam at 150 °C302 °F. Throughout takeoff, the area below the engine will be heated to a maximum temperature of 2926.9 °C5300.42 °F, although at the heating is weak.
Tips
- Different from more powerful engines, Steam Engine does not require fuel tank or oxidizer tank.
- Steam has to be piped in for fueling. Use Insulated Gas Pipes and use the shortest route until pipes made from Insulation can be made (late game). After fueling completion, excess steam should be vented from pipes as even Ceramic insulated pipes will eventually crack as the steam loses heat and condenses (even in a vacuum - the pipe itself absorbs heat from the steam).
- Alternatively, steam can be transported with normal Gas Pipes made of thermally reactive materials like Mafic Rock, so the pipes will quickly reach thermal equilibrium with the steam. Once the pipe's temperature is above the effective condensation point of steam (96.4 °C205.52 °F), there should be no risk of steam condensing and damaging the pipe assuming the pipe is in a vacuum with no external heat exchange.
- Cool Steam Vents provide adequate amounts of steam. Make a chamber with Insulated Tiles, place some heat generating devices to prevent the steam from condensing - Thermo Regulators can be used to cool hydrogen for other uses whilst keeping the steam hot.
- Cool Steam Vents are far from the surface, so the additional heating for the steam should take this into account.
- When building the first rocket, you will be restricted to using Research Modules which will provide Data Banks for future research purposes. The maximum usable rocket weight will be restricted to 4950 kg to reach the first line of planets (4950 kg = -8000 km range penalty. 18,000 km max range - 8,000 km = 10,000 km). This will allow you to build
- 1 Steam Engine (2000 kg mass + 900 kg steam)
- 9 Research Modules (1800 kg mass)
- 1 Command Capsule (200 kg mass)
- Steam Engine will not accept fuel if it is entombed under Regolith
- A rocket with Steam Engine as the only power source may reach 10,000 km destinations.
- A rocket with Steam Engine and Solid Fuel Thruster may reach 20,000 km destinations.
- Steam Engine does not take the Wrong Element Damage and immediately eject the gas.
- A rocket chimney spawning the entire height of the asteroid allows getting more water than is used to launch the rocket. Rough numbers estimate above 800g/s of water when launching to the closest destination. Due to the relatively low Steam temperature, the power return is negligible. For a good power return, use Hydrogen Engine.