The energy harvesting (EH) of radio frequency (RF) has taken attention to solve the wireless devices’ energy problem. On the other hand, relays play a crucial role in improving device-to-device (D2D) communication performance with regard to data rate and energy efficiency (EE) as well as network coverage and extendability. Relay nodes (RNs) can take advantage of EH while benefiting the D2D networks. This paper provides an answer to the controversial question of whether it is worth using RF EH in relay-based D2D communication. As such, it presents the main EH protocols for relay-based D2D wireless networks, namely power splitting (PS) and time switching (TS). Besides, it models a network of relay-based D2D communication links sharing the spectrum of a number of conventional communication links under the quality of service (QoS) conditions. The results show that the effectiveness of EH depends on factors like the density of the nodes in the investigated area.