Wavelength-selective solar photovoltaic systems to enhance spectral sharing of sunlight in agrivoltaics

Agrivoltaic systems offer a solution to the debate over using agricultural land for food production or energy conversion. Conventional silicon solar panels often shade plants excessively, impacting growth. Wavelength-selective photovoltaic (WSPV) technologies address this by allowing the transmission of beneficial wavelengths for photosynthesis while converting less useful ones into electricity. Wavelength selectivity can be achieved through various methods, such as by tuning photoactive layers, applying colored semi-transparent layers, utilizing mirrors and lenses, or designing spectrally selective luminophores. While evidence suggests that these technologies effectively share sunlight, many of them are yet to be fully implemented and evaluated. This review covers current WSPV technologies, discussing their classification, status, and future prospects. It also provides appropriate PV performance metrics for WSPV technologies in agricultural applications and advocates for standardized reporting practices in crop experiments conducted under WSPV systems, accompanied by practical suggestions. Solar cell efficiency limits under spectral sharing for crop production and the optimal band gap under varying levels of photosynthetically active radiation for crop growth are further examined as guidance for future development.