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.