Solar Powered Raspberry Pi for Internet of Things and Wireless Sensor Networks

This paper follows the design, development and later testing of a solar powered Raspberry Pi for Internet of Things (IoT) and wireless sensor networks for environmental sensing, specifically for high spatial resolution irradiance ground measurements. The problem of solar irradiance intermittency can be addressed using either high orbit remote sensing (i.e., satellite imagery), or either using a network of ground stations for observations and measurements. The latter being the more accessible in terms of cost, the paper will tackle developing and testing a single node of such a network. Being a solar powered node, the aim will be to have the network autonomous in terms of energy. This single node ground station has environmental sensors for temperature and irradiance measurements and a camera connected to it for cloud optical flow estimations. The meteorological profile of the site where the device is installed demands an energy consumption scheduler used to turn on or off various modules of the node, depending on the available battery level and the solar resource to keep the measurements integrity at a high level. The node can act as a standalone Internet of things multiprotocol gateway considering that all the primary ways of connectivity are available (cellular, Wi-Fi and Bluetooth).