HERF is a mobile application developed by for owners of distributed PV power plants, There are more functions, such as module-level monitoring, real-time data display for both plant-level & module-level as well as daily, monthly, annual, and total energy display. Furthermore, you can easily see the alarm information with the equipment, which could assist the owner in monitoring the operation of the PV power plant, ensuring normal operation of the power plant and obtaining of the expected yield.