New battery recharging techniques should be developed for the continuous operation for the wireless devices and networks. This study investigates the setup of multi-source energy harvesting system and determines an efficient operating point to capture energy from various energy sources. With our multi-source energy harvesting system, we aim to operate system in different environmental conditions. The continuity of recharging the batteries all the time is a critical aspect of this approach. With this objective, we use multiple energy sources. We design our test set-up and perform measurements. Specifically, we use radio frequency, thermal, and solar energy harvesting sources in the same circuit structure. As expected, our results demonstrate that the continuity of charging is obtainable in the presence of multiple energy sources, which provides a robust energy harvesting system.