New research has the solar world buzzing this week, as it theorizes a 190% efficient solar cell could be the future. The research is still in the proof-of-concept phase, but other research into solar cells have also seen results past the 100% mark. This challenges the decades long theory, the Shockley-Queisser limit, which has stated there is a specific efficiency threshold that solar cells simply cannot exceed. The theory emerged in the 1960's to describe the upper limit of silicon photovoltaic technology. The initial limit was set at 30% and later raised to 33.7%.
More complex systems have surpassed this threshold easily. In 2022, researchers at the Fraunhofer Institute for Solar Energy Systems in Germany achieved 47.6% for a solar cell through mixing various compounds. Other technologies have tried tweaking the photovoltaic effect by harvesting heat as well as light to gain greater efficiency. The latter is the new technology that proposes 190% quantum efficiency and is in the theoretical phase at Lehigh University in Pennsylvania, headed by physics professor Chinedu Ekuma.
“In traditional solar cells, the maximum EQE [external quantum efficiency] is 100%, representing the generation and collection of one electron for each photon absorbed from sunlight. However, some advanced materials and configurations developed over the past several years have demonstrated the capability of generating and collecting more than one electron from high-energy photons, representing an EQE of over 100%,” Lehigh University explained in a press statement.
The new quantum material is just a material at this point in time, not a solar cell, but that will come with more research and development. While it's still in the preliminary phases, this new technology provides an exciting proposal that solar technology could one day replace fossil fuels and other harmful modes of non-renewable energy.
To get into the nitty-gritty details of this research, you can find more information here.