2.2. PBTE and environmental impact payback time (PBTI)
PBTE is a time period defined for a PV system to generate the same amount of energy that will compensate for the energy consumed to produce the system itself (Fthenakis and Kim, 2011;Fu et al., 2015). Similarly, PBTI is defined as the period required for a PV system to avoid the same amount of environmental impact that was generated to produce the system itself.