The miniaturization of devices at the nanoscale is expected to widely extend the Internet of Things (IoT) to the Internet of NanoThings (IoNT), opening the door to the emergence of several unprecedented applications in several fields (until now unimaginable). One of these applications, called Software-Defined Metamaterials (SDMs). SDMs enables the construction of unprecedented class of smart materials, which could change their electromagnetic behavior and could be reconfigured at runtime, utilizing embedded nanonetwork in their structure. Efficient energy-based data routing is a critical and challenging enabler of future SDMs applications, due to highly lossy conditions requiring a path redundancy, and the tiny storage capacity of nanodevices and inability to apply classical energy supply techniques. However, novel energy harvesting technologies have been proposed to replenish the energy supply of nanodevices, which could achieve an infinite lifetime, provided that the consumption processes and energy harvesting are jointly designed. The present study proposes a distributed cluster-based multi-hop point-to-point routing scheme for 2D dense homogeneous nanonetworks, targeting applications in SDMs. Extensive evaluation using nano-sim tool on NS-3 shows that the proposed scheme widely enhances the performances of the pioneering routing scheme proposed by Liaskos et al. in terms of energy efficiency and communication reliability.