The solar panel of the Sunnybag POWERTAB works best when it is inclined at a 90°angle to the sun. You can either connect your devices to the USB output to charge them directly or you can charge the built-in battery to use the energy later on. If the solar panel is positioned in full sunlight, it will charge a smartphone within 3 to 4 hours depending on the model. Larger devices, such as drones or tablets, take about 6 to 8 hours. In cloudy weather or when the orientation towards the sun is not optimal, the charging times increase accordingly.