Abstract— Solar power generation, mainly from photovoltaic (PV) systems, has been rapidly growing in Jordan. However, increased PV penetration in distribution systems can cause multiple technical issues; namely, overvoltage at grid buses and overloading at the substation transformers in case of excessive reverse power flow. Thus, it is vital to be able to estimate the capacity of distribution systems for distributed generation (DG); and gradually find methods to increase it to allow for more integration of on-grid PV systems. In this paper, a simple deterministic method to estimate the PV capacity of distribution systems is presented, utilizing incremental increase in PV power injection. This method, which does not require detailed knowledge of the distribution grid’s load profile, can be used to estimate how much installed PV power can be incorporated into the distribution system without violating certain power quality constraints. The proposed method is applied to a 73-node 33 kV distribution system located in the town of Al-Qatraneh in Jordan. Additionally, two operational methods for increasing the PV capacity are proposed to improve the ability of the system to incorporate more solar energy without the need for expensive upgrading of the distribution.