Ultra-high luminescence efficiency as a technology enabler: solar cells, thermophotovoltaics, and optoelectronic refrigerators

To approach the Shockley-Queisser limit, a solar cell must embody the principles of efficient light-emitting diode (LED) design. Here we describe how ultra-high luminescence efficiency, both internal and external, is the basis for the present efficiency records in solar energy conversion. These developments have provided an impetus for new energy technologies, which rely on the same design strategies to reach their theoretical limits. Thermophotovoltaics, the conversion of terrestrially produced thermal radiation to electricity, can now approach >50% efficiency. Ultra-efficient photovoltaics and LEDs also enable optoelectronic refrigerators with the potential to surpass other methods of solid-state cooling in energy efficiency.