| Title |
An Analytical Approach for Transmission Use-of-System Charges for a Renewable Energy Power Purchase Agreement |
| Authors |
김동현(Dong-Hyun Tony Kim) ; 박채운(Chaewoon Park) ; 박종배(ong-Bae Park) ; 노재형(Jae Hyung Roh) |
| DOI |
https://doi.org/10.5370/KIEE.2023.72.7.801 |
| Keywords |
Transmission Use-of-System Charges (TUoS); Power Transfer Distribution Factor (PTDF); RE100; Renewable Energy; Multiple Transactions |
| Abstract |
This study proposes a new method for determining Transmission Use-of-System Charges (TUoS), considering the impact on the grid as the amount of renewable energy generation increases. With the rise in Power Purchase Agreements (PPAs) for renewable energy, there has been an increase in instances of counter-flows, which are contrary to the dominant flows and directions of existing transmission lines. This phenomenon has resulted in lowering the utilization rate of the lines. However, such considerations were not reflected in the existing TUoS calculation methods in South Korea. Thus, this paper introduces a novel method for determining TUoS, integrating the impact of increased renewable energy generation on the grid. In order to calculate the change in line power flow due to each participant's power injection to the grid, we utilize linear characteristics of the Power Transfer Distribution Factor (PTDF) in an AC system. The method proposed in this paper has the advantage of being able to calculate power flows for each line with simple matrix calculations due to the linear nature of Fast Decoupled Power Flow, especially when numerous renewable energy PPAs are taken place. This study conducted simulations by dividing scenarios based on the influence each market participant has on line power flow, and combinations and physical distances of PPAs contract entities, utilizing IEEE 5-bus and 14-bus systems, and analyzed each of the TUoS. |