HeliNet energy subsystem: an integrated Hydrogen system for statospheric applications

HeliNet is a telecommunication infrastructure based on HAVE - High Altitude (17 km) Very long (6 months) Endurance - unmanned solar aerodynamic platforms, named HELIPLAT (Helios Platforms). HELIPLAT is a monoplane driven by eight brushless motors, twin-boom tail type. Its energy subsystem is based on a closed Hydrogen cycle. The platform surfaces are covered with photovoltaic arrays; during the day, the solar power is used to supply the electric motors and to feed an electrolyser which produces hydrogen and oxygen. The gases are stored at high pressure and used during the night to feed the fuel cells which supply the motors; the water feeds the electrolyser to close the cycle. The key features of this hydrogen-based propulsion system are the cost-effectiveness infrastructure (compared to satellite systems), and the sustainability of the solution thanks to the favourable relationship with the environment: it does not induce any atmospheric and electromagnetic pollution.