Solar installations can be seen everywhere today, and many more are planned – both large solar parks and small installations, privately on house roofs. In addition, there are even smaller applications with an output of just a few watts. Inverters or charge controllers with MPP trackers are commonly used to optimize energy yield. Optimization of a system using real light is difficult due to fluctuating conditions. This article describes a simple and inexpensive solar panel simulator that electronically mimics a 50-W solar panel. In order for a simulator to be able to adjust parameters such as different solar radiation and other environmental influences, the short-circuit current ISC, the open-circuit voltage VOC, and the temperature coefficient TC are adjustable in this solar panel simulator. This means that you can also simulate other modules than the one described in the “50 W Panel from Phaesun” text box that is simulated as an example in this article.   Simulation Circuit L...