Thermo-photovoltaic power generator for efficiently converting thermal energy into electric energy

A thermo-photovoltaic power generator for efficiently converting thermal energy into electric energy, comprising:

• a selective thermal emitter having micropatterned structures for receiving thermal energy and emitting thermal radiation with black body emissivity over a range of wavelengths;
• low-bandgap photocell means responsive to thermal radiation at wavelengths within a particular band of said range of wavelengths and operative to convert such thermal radiation to electric energy;
• and
• a band pass filter disposed between said thermal emitter and said photocell means for transmitting thermal radiation from said emitter at wavelengths within said particular band to said photocell means, and for reflecting thermal radiation at wavelengths outside said particular band back to said emitter.

A thermo-photovoltaic power generator comprising:

• means forming a reflective cavity and including a transparent window;
• a heat source for generating thermal energy disposed within said cavity;
• a selective thermal emitter formed of rare-earth ceramic material disposed within said cavity between said heat source and said transparent window and having micropatterned structures for emitting thermal radiation with black body emissivity over a range of wavelengths;
• low-bandgap photocell means disposed outside said cavity for converting thermal radiation at wavelengths within a particular band of said range of wavelengths to electric energy;
• and
• a band pass filter disposed between said thermal emitter and said photocell means for transmitting thermal radiation from said emitter at wavelengths within said particular band to said photocell means, and for reflecting thermal radiation at wavelengths outside said particular band back to said thermal emitter.