Horizon Unmanned Systems, a company based in Singapore, just announced a new type of quadcopter that runs on hydrogen instead of regular old lipos (lithium polymer batteries). The Hycopter uses a fuel cell to convert hydrogen into electricity and they claim that it can fly for up to 4 hours on a single charge of hydrogen gas. The tanks a built-into the frame and the fuel cell can be shifted to accomodate up to 1 kg of cargo, with a reduced flight time of 150 minutes.
Unlike any other rotorcraft, HYCOPTER makes use of its frame structure to store energy in the form of hydrogen instead of air, eliminating energy storage weight. With less lift power required, HYCOPTER’s ultra-light fuel cell turns the hydrogen in its frame into electricity to power its rotors.
This technology sounds great but I would like to see an actual demos and not just a WIX-powered website and a PDF. Check out their website for the full details.