New Fuels Are Being Developed For Satellite Propulsion - Part 2 of 2 Parts

New Fuels Are Being Developed For Satellite Propulsion - Part 2 of 2 Parts

Part 2 of 2 Parts
    HyproGEO is a project coordinated by Airbus, a European aerospace company. This project is working on a non-toxic propulsion system focused specifically on satellites in geostationary orbit around the Earth. These satellites travel at about twenty-two thousand miles per hour and remain in position over a particular point above the Earth. They are typically used for communications and broadcasting. Dr. Frischauf is with SpaceTec Partners which is a member of the HyproGEO consortium. He said, “To get up there, it takes quite a lot of energy.” 
     Right now, the energy needed to get satellites out to geosynchronous orbit is provided by hydrazine-based fuels. HyproGEO is working on a hybrid propulsion system that utilizes hydrogen peroxide instead of hydrazine. The new fuel is ninety eight percent hydrogen peroxide and is highly acidic. However, it is still much less dangerous to work with than hydrazine. Hydrogen peroxide also breaks down into oxygen and water. This process does not release fumes that are toxic to humans.
      Geostationary satellites are designed to operate for a decade or longer. This means that their propellants which are after launch to maneuver and change orbit must be able to operate reliably and safely for at least a decade and a half. Frischauf said, “You have to make sure that it will still be running after 15 years, so it should be a simple system, because if it's complicated there's always a risk that something breaks.”
     The HyproGEO solution to satellite propulsion is a hybrid system. Hydrogen peroxide is passed over a catalyzer which results in the production of very hot oxygen and water vapor. The oxygen can be used to propel a satellite or it can be used to ignite another substance which will provide extra boost. Frischauf said, “When you control the flow of the oxygen, you can control the thrust of the engine.”
     The HyproGEO team successfully constructed a test engine which could store the new propellant. Then they designed an engine that used the fuel as intended by their design. That work was completed in 2018. Since then a Norwegian defense company named Mammo has sent a rocket to an altitude of sixty-six miles in three minutes with the HyproGEO hybrid engine. This performance is similar to the performance of typical suborbital rockets using traditional propulsion systems.
     These new propellants and engines are not just a benefit to those who must work with the old toxic fuels. If widely adopted, the new fuels will make the whole infrastructure more efficient and cheaper. Kneižys says that the NanoAvionics EPSS system costs about one third as much as traditional satellite engines that use hydrazine-based fuels.
    If these new fuels and engines are so great, why have they not been adopted more widely by now? One major problem has been that the new fuels and systems have not been able to sustain long-term firing that is needed to raise satellites from low Earth orbits to geosynchronous orbit. HyproGEO has managed to solve this particular problem which should speed adoption.
     The existing satellite launch industry is heavily invested in the use of hydrazine. This infrastructure would have to change in order to stop using hydrazine and that will cost money and time. Frischauf said, “It always takes a bit of an impetus, a bit of a push to make sure the new technology can prevail.”