Sensitivity Study on Special Rate for Renewable Energy Based on the Design of Optimized Model for Distributed Energy Resources Capacity in Buildings

Abstract

To promote energy transition, various incentive schemes are being implemented to improve the economic return of distributed energy resources (DERs). In this circumstance, research on the optimal capacity design and operation of photovoltaic (PV) power generation and energy storage system (ESS) devices is important for ensuring the economic efficiency of DERs. This paper presents optimal capacity calculation modeling and operation methods for facilities considering the long-term operational environment changes of DERs in a self-consumption building (a concept not fully reflected in preceding studies). Based on this, key policy variables are derived for a special rate for a renewable energy system. To do this, we first analyzed the DERs' operating environment, by studying the basic operation types of PV and ESS and examining the detailed benefit structure of a special rate for renewable energy. The optimal capacity of PV and ESS with the lowest net cost was estimated by applying various parameters when considering long-term operation of 15 years, and by setting rules of the special rate for renewable energy. It was confirmed that the combined operation of peak reduction and rate reduction was the most economical approach. The constraints for this examination considered the maximum capacity of solar power, the maximum/minimum state of charge (SOC) of ESS devices, simultaneous charging, the continuity of the SOC, power supply management, and peak load management points. The case study confirms the economic sensitivity of cost and benefit items when applying a special rate for renewable energy based on actual load data. As a result, it is possible to estimate that this study will lead to core policy variables that can help decision making.