Abstract: A miniature thermo-photovoltaic (TPV) device for generation of electrical power for use in portable electronic devices. A TPV power source is constructed to provide a heat source chemical reactor capable of using various fuels, such as liquid hydrocarbons, including but not limited to propane, LPG, butane, alcohols, oils and diesel fuels to generate a source of photons. A reflector dish guides misdirected photon energy from the photon source toward a photovoltaic array. A thin transparent protector sheet is disposed between the photon source and the array to reflect back thermal energy that cannot be converted to electricity, and protect the array from thermal damage. A microlens disposed between the protector sheet and the array further focuses the tailored band of photon energy from the photon source onto an array of photovoltaic cells, whereby the photon energy is converted to electrical power.

Abstract: The invention is a propulsion system for a buoyant aircraft. The invention comprises a gas storage container filled with a lighter-than-air gas and having outer walls of which at least a portion thereof are flexible. A system is provided to move the flexible portions of the walls alternately inward and outward varying the internal volume of the container, thus, varying the buoyancy of the aircraft and providing a propulsive force. Air foils mounted on the aircraft are adapted to provide trimming forces as the aircraft descends and ascends.