Background and State of the Art
A new era for tandem photovoltaic cells

Photovoltaic cells convert incident solar energy into electrical energy. Although the photovoltaic (PV) effect was discovered in 1839 by Edmond Becquerel, it was not until the 1950s that photovoltaic technology began to take off. This growth was made possible by a gradual understanding of quantum physics (Einstein, De Broglie, Heisenberg, Schrödinger, Fermi, etc.) and was fueled by the simultaneous advent of the electronics revolution.

From 6% in 1954, the efficiency record for “conventional” silicon cells reached approximately 28% by 2025. While such an efficiency—less than one-third of the incident energy—may seem modest, it is interesting to compare it with other technologies.