Silicon solar cells are one piece in the puzzle of a successful energy transition towards renewable energies. Unfortunately, many outdoor parameters such as high temperatures have a detrimental impact on solar cells' energy output. To enhance the understanding of silicon as a semiconductor used in photovoltaics, this thesis investigates the temperature dependence of silicon and silicon solar cells. Measurement approaches for spatially-resolved temperature-dependent characterization of silicon wafers and solar cells were developed being based e.g. on photoluminescence imaging or lock-in thermography at realistic operation temperatures. The temperature dependence of three different regions of silicon solar cells is investigated in detail: the bulk, surfaces and diffused regions. The acquired knowledge is employed in a sensitivity analysis to demonstrate how new findings about temperature sensitivity of silicon solar cells influence numerical simulations of silicon solar cell devices. Finally, all developed approaches of this work are combined to predict silicon solar modules' energy yield in spatial resolution via measurements at wafer level before metallization.