A Distribution Use of System Charge Calculation for Solar Photovoltaic Systems in Thailand

With the Thai government aiming to supply renewable energy accounting for 30% of the country's energy consumption by 2037, the role of consumers is becoming prosumers. However, the energy generated by photovoltaic (PV) systems has an impact on the distribution system, which is managed by a distribution system operator (DSO). This paper proposes a method for calculating the distribution use of system (DUoS) charge, with a focus on the actual amount associated with the distribution system price in Thailand's electricity bill structure. The proposed method aims to accurately reflect DSO's recovery needs without negatively affecting consumers who install PV systems. The case studies are designed to compare the DUoS charge under time-of-use and progressive rates, considering scenarios related to PV system energy generation, load support, and energy flow into the distribution system. Through simulation results and discussion, this paper provides insights into determining the appropriate DUoS charge in the context of PV systems in Thailand, contributing to the efficient integration of PV systems while maintaining fairness and sustainability in Thailand's energy distribution.