A solar panel is one alternative energy solution that is widely used today. Solar panels consist of two main types, namely polycrystalline and monocrystalline. The two solar panels have physical differences and the ability to produce electrical energy. Therefore, we compare two solar panels in order to conclude which type of solar panel is the most effective in producing electrical energy. The area used is plateau areas with a mountainous contour and has low humidity and temperature. Data is collected for three days. The solar panels used have a capacity of 200 Wp each. As a data logger, Arduino and several supporting components are used. Polycrystalline solar panels produce a greater voltage than monocrystalline types from the first day to the third day. However the current produced by the two solar panels tends to be the same. The average total energy produced by polycrystalline solar panels is 665.46 watts and monocrystalline solar panels is 500.62 watts. It can be concluded that in mountainous areas it is more efficient to use a polycrystalline type of solar panels.