Winter Wheat (Triticum aestivum L.) Grain Yield, Quality, and Net Photosynthesis When Grown Under Semi-Transparent Cadmium Telluride Photovoltaic Modules Near Maturity

Semi-transparent cadmium telluride (ST-CdTe) photovoltaic (PV) technology is based on the use of CdTe in a thin film (2-8µm) to absorb and convert sunlight into electricity. The thin film is deposited onto clear glass and can be custom abraded to produce ST-CdTe PV modules of a desired transparency level (e.g. 50% full sun/50% transparency) making it an intriguing option for agrivoltaics (AV) applications. Recent improvements in ST-CdTe PV technology have matched the efficiency of crystalline silicon (c-Si) PV with the levelized cost of energy production far lower than conventional gas, coal, and nuclear generation [1]. A field experiment was conducted whereby ST-CdTe PV modules of two transparency levels (20% and 50%) and a full sun control (100% transparency) were temporarily installed in a RCBD with three replicates over winter wheat (Triticum aestivum L.) plants after anthesis and until harvest. The average net photosynthetic rate (Pn) of the full sun control was significantly higher than the 20% ST-CdTe PV module, but not different from the 50% transparency module. Measured factors for yield and protein content were statistically insignificant, except for wheat head number, which was significantly higher under 50% ST-CdTe PV than both the 20% ST-CdTe and full sun control. These results provide evidence that ST-CdTe PV module technology can provide renewable energy while balancing wheat yield potential and grain quality. The ability to adjust the transparency levels of the modules make ST-CdTe another PV technology option to consider for AV applications.