# Day-Ahead PV Generation Scheduling in Incentive Program for Accurate Renewable Forecasting
## 1 Introduction  
In recent years, South Korea has been implementing a 2050 carbon-neutral strategy and a renewable energy 3020 plan, resulting in a substantial increase in renewable energy generation. In particular, photovoltaic (PV) generation has experienced significant growth. However, inaccurate forecasting of PV generation can negatively affect the stability of the power system and lead to congestion problems in power lines [1, 2, 3]. In order to mitigate the problems caused by energy deviations in PV generation, South Korea has introduced an incentive program beginning in 2021. The incentive program promotes efficient and stable power system operation by mitigating renewable energy volatility and reducing associated costs. This incentive program rewards renewable energy resources that can provide fewer energy deviations [4]. It encourages energy deviation reduction through more accurate self-forecasting of PV generators and the use of ancillary resources within the PV site. From the perspective of resources that achieve accurate forecasting, they can receive an additional benefit of approximately 5% of the energy market price. PV generators typically offer their forecasted PV output as part of their generation schedule without making additional adjustments. In this situation, PV sites may try toincrease their revenue by improving the performance of their forecasting model. However, there are inherent limitations to achieving significant improvement due to the fundamentally uncertain nature of weather. Therefore, assuming that the forecasting accuracy is already high enough, additional energy deviation mitigation measures are needed. In order to mitigate energy deviation, energy storage system (ESS) operation and PV curtailment can be considered. First, by establishing an appropriate ESS operational strategy, it is possible to mitigate energy deviation [5], resulting in increased incentive revenues [6; 7]. For PV sites with ESS, if actual PV power exceeds the forecast threshold eligible for incentives, the incentive level can be increased by reducing the energy deviation through ESS operation [8]. However, there may be a limitation in reducing the energy deviation due to the physically limited capacity of ESS [9]. In addition, ESS can charge during higher market prices and discharge during lower market prices to mitigate energy deviations [10], which will reduce revenue from the energy market. Alternatively, power curtailment can mitigate the energy deviation by limiting power output by setting an upper limit [11; 12; 13]. In contrast to ESS operation, power curtailment does not require installation investment, as the curtailment is controlled within the generator. However, power curtailment can only control unidirectional energy deviations that exceed the predicted power generation by setting output limits. Additionally, curtailing power can decrease revenue from the energy market. Both ESS and curtailment can mitigate energy deviations and increase incentives. On the other hand, they can reduce revenues from electricity sales in the energy market [14]. In general, increasing power generation is profitable when market prices are high. However, there are instances where it may be more advantageous to forgo a portion of the generation revenue in exchange for higher incentives. PV sites should make an optimal generation schedule to enhance both the generation revenue and incentives simultaneously through co-optimization. For the day-ahead market, the generation schedules of PV sites should be based on the predicted PV output. However, in real-time operations, PV output will differ from the predicted PV output, and this uncertainty makes it hard to determine the generation schedule that brings the highest revenues. Numerous studies have been conducted on day-ahead scheduling to enhance the profitability of PV sites.