OhmSpace

OhmSpace is a Turin, Italy-based space propulsion startup founded in 2020, developing next-generation resistojet electric thrusters for small satellites using additively manufactured (3D-printed) resistive heating elements that achieve dramatically higher efficiency than conventional resistojet designs. The company's technology targets the growing market for low-cost electric propulsion in the 1U–12U CubeSat and small microsatellite class, where water or other non-toxic propellants can be thermally accelerated to provide station-keeping and drag compensation thrust.

Conventional resistojets work by passing propellant gas through a chamber heated by electrical resistance coils, raising propellant temperature and thus exhaust velocity (specific impulse). Traditional designs are limited by the maximum temperature achievable in the resistive heating element before structural degradation — typically Isp of 150–200 seconds for water resistojets.

OhmSpace's innovation is using 3D-printed tungsten or other refractory metal resistive elements with optimized microstructure geometries that maximize surface area, heat transfer efficiency, and thermal uniformity, enabling higher operating temperatures and claimed efficiency improvements up to 70% over conventional resistojet designs.

Water resistojets have particular appeal for CubeSat operators because water is non-toxic (simplifying launch manifest integration compared to hydrazine), storeable at ambient temperature (no pressurized propellant tanks needed for low-impulse mission profiles), and available in large quantities at low cost — making it practical for constellation operators to buy water-propellant satellites commercially off-the-shelf.

The Isp achievable with water (around 150–300 seconds depending on temperature) is much lower than Hall-effect or ion thrusters, but resistojets are simpler, cheaper, and suitable for missions with modest delta-V needs like altitude maintenance in VLEO or station-keeping in medium-LEO.

OhmSpace operates within Turin's growing aerospace cluster anchored by Thales Alenia Space's major Italian facility and the Polytechnic University of Turin (Politecnico di Torino), which provides engineering talent and research partnerships. The company participates in the Italian space startup ecosystem supported by ASI (Agenzia Spaziale Italiana) and ESA BIC Turin. OhmSpace competes with Enpulsion (FEEP thrusters), NanoAvionics Propulsion (green monopropellant), and ThrustMe (iodine cold gas/RF ion) for the CubeSat propulsion market.