RFID (radio frequency identification) implementation in large buildings requires setting up a grid that implies a lot of RFID readers. Although these  readers  are  not  power  greedy,  their  usage  can  affect  the  electricity bill in the long run. In this paper, we study the worthiness of  upgrading  to  a  motion  sensor-based  smart  RFID  system,  from  a  power-efficiency  point  of  view.  A  decision-support  protocol  is  developed  for  this  purpose  that  considers  the  occupancy  ratio  of  the  environment  where  the  system  is  implanted  in  deciding  its  feasibility,  given  that  the  energy  drain  depends  on  it.  Moreover,  we  discuss  the  optimal  way  for  integrating  the  motion  sensor  into  the  RFID system’s architecture, as this insertion is able to highly reduce the power consumption in the standby mode, in exchange for slightly augmenting the drain during the reading mode. Finally, the developed decision-support  protocol  is  demonstrated  through  an  analogy  on  the studied upgrade to assess its overall feasibility. The overall results confirm the suitability of the upgrade for most environments.