Design and implementation of a low-power energy management module with emergency reserve for solar powered DTN-nodes

DTN nodes often idly wait for contacts and unnecessarily consume energy during these periods. For solar-powered nodes this means that solar panels and batteries could be much smaller with an efficient energy management, reducing the physical size of these nodes. We present our design of a solar-powered DTN node including a module that handles solar charge management, energy management and a discovery mechanism to wake sleeping nodes. Moreover, the system senses the remaining battery capacity, and keeps a reserve for emergency communications. Our evaluation shows that the power management module's design is energy-efficient and performs as intended. Furthermore, we evaluate the discovery mechanism. The results show that the capabilities of the module offer a promising new approach to the implementation of energy efficient routing in DTNs.