For a small satellite, the propulsion system enables it to manoeuvre in orbit and carry out its mission objectives. SteamJet is a water-based propulsion system for CubeSats. It uses water to generate thrust. The SteamJet TunaCan has a wet system mass of approximately 0.54 kg, provides 5–20 mN of thrust, and delivers a specific impulse of 172 s, with a total impulse of up to 219 Ns. Its peak input power is below 20 W. In this article, we’ll explore how SteamJet works and what advantages water-based propulsion can offer space missions. That said, the final capabilities depend on the system’s parameters and the specific requirements of the satellite.
What Is Water-Based Propulsion for CubeSats?
Water-based propulsion is a technology that generates thrust by heating a propellant. Then it is accelerated through a precision-engineered nozzle. This CubeSat propulsion system can be used to change the orbit and perform other mission tasks.
1. Water is easier to work with than many traditional types of fuel
For a small team, every stage of satellite preparation matters. Fuel must be stored, loaded, and checked before launch. The simpler these processes are, the easier it is to plan the satellite’s integration and preparation.
How Water Propulsion Can Simplify Things
Unlike hydrazine, which is highly toxic and requires stringent handling precautions, water has no chemical hazard profile. SteamJet water-based propulsion systems use water as a propellant in a very low-pressure system, simplifying propellant handling and supporting safer integration into CubeSat missions.
Safety depends not only on the type of propellant. The design may include pressurised components, heaters, and electronics. Therefore, water propulsion simplifies most stages of operation.
2. Water propulsion simplifies launch preparations
Water is easier to work with during certain stages of satellite preparation. Storage and refuelling procedures require fewer special precautions compared to other fuels. As a result, the installation and integration of the propulsion system is streamlined.
Accessibility and Costs
When the propellant is easier to handle, satellite preparation requires less effort. On top of that, SteamJet thrusters have an affordable cost, which makes them an attractive option for CubeSat programs.
3. A water-based propulsion system can be adapted to CubeSat constraints
CubeSats have limited space and mass constraints. Therefore, when selecting a propulsion system, it is important to understand in advance a few important characteristics. Namely, how much space the thruster itself, the fuel tank, and other necessary components will occupy. The system has to be compact. It should be evaluated based on its performance characteristics, not just its compactness and type of propellant.
Integration with Other Satellite Systems
The thruster must work in conjunction with the spacecraft’s other components and not interfere with their placement. The better the system fits into the CubeSat design, the easier it is to plan the assembly and connection of the equipment.
4. The propulsion system expands the capabilities of a CubeSat
A CubeSat propulsion system can support several mission tasks, depending on its performance and the spacecraft’s requirements:
- Orbit correction: requires precise impulse delivery and sufficient total impulse to achieve the desired orbital change.
- Station-keeping: depends on the available propellant, thrust capability, and mission duration.
- Collision avoidance: requires sufficient manoeuvring capability, time to manoeuvre, and appropriate spacecraft guidance and control.
- Constellation management: may involve adjusting the relative positions of satellites, which requires sufficient total impulse and manoeuvre time.
- Major orbital changes: depend on the required change in velocity (Δv), spacecraft mass, and available propellant.
5. A water-based propulsion system can help shape the entire mission
To assess a system’s environmental impact, one must consider more than just the working fluid. The engine’s materials and manufacturing process, its energy consumption, and its operating conditions are also important.
Service Life and Mission Completion
When planning, it is important to consider how long the satellite will operate and what will happen to it after the mission is complete. The propulsion system should be part of such a plan, for example, if it helps change the satellite’s orbit.
A water-based propulsion system can simplify the handling of the propellant, help integrate the engine into a CubeSat, provide the satellite with greater manoeuvrability, and become part of a well-thought-out mission plan. However, these advantages depend on the characteristics of the specific system. It is important to consider its mass, dimensions, thrust, power consumption, and propellant supply, as well as its cost and mission completion requirements.
About SteamJet Space Systems
SteamJet Space Systems is a leading UK-based provider of high-performance satellite propulsion solutions. We specialise in water-based propulsion solutions designed specifically for CubeSats and Small Satellites (SmallSats), prioritising operational safety and rapid launch integration.
By pioneering the use of green propellants and intelligent thermal engineering, SteamJet enables complex LEO (Low Earth Orbit) manoeuvres — including orbital maintenance, collision avoidance, and de-orbiting — without the risks associated with toxic hydrazine or high-pressure cold-gas systems, thereby advancing green propulsion for space missions.
Steamjet Propulsion Technology
Our modular systems are engineered for seamless integration and maximum safety compliance:
Steamjet TunaCan Thruster: A compact, high-efficiency solution for 1U-3U CubeSats.
Steamjet TunaTank Thruster: A safe, high-performance electrothermal propulsion system.
Steamjet Thruster One: Scalable propulsion for larger SmallSat constellations.
Discover how SteamJet’s sustainable space propulsion innovations are providing the safety and reliability required for the next generation of crewed and robotic missions. Contact our engineering team for technical specifications and ICDs.