## 2 Load Profile Development
### Historical Profile vs. Flattened Profile  
The research performed previously by the authors established a (1) typical load profile and (2) a load profile that exhibits more flattened characteristics due to high penetrations of PV, ES applications, and EV charging [6]. These profiles are utilized in this research as Profile B (typical load profile) and Profile A (load profile with high penetrations of DER and DSM). The profiles were developed by combining field measurements and results from numerous research projects. A typical substation transformer load profile (Profile B) was established from load profile descriptions given in Willis, examples provided in IEEE Std. C57.91-2011, and field measurements acquired in McBee, which also correspond to the results presented in research by [PERSON], [PERSON], and [PERSON] [1; 2; 8; 19]. To evaluate the impact of high penetrations of PV, load profile changes established in research performed by CallSO was applied to the typical load profile [5]. These results also aligned with profiles developed in research performed by [PERSON] and [PERSON] [20]. To account for the impact of high penetrations of ES applications, the load profile changes established in [PERSON]'s research was applied to the typical profile [4]. These profile augmentations align with changes produced by hybrid PV and ES systems that are utilized to improve grid stability and customer participation [21; 22; 23; 24]. Utilizing time-of-use practices by utility companies such as Pacific Gas & Electric in California that incentivize customers to charge during the period between 11 pm and 7 am, the impact of EV charging was applied to the typical load profile [25]. These load profile changes align with the predictions documented in research by [PERSON], [PERSON], and [PERSON] [26]. The resulting load profile exhibits more flattened characteristics than the historical profile. Given the goal of DSM applications and the system impact of DER applications, these profile variations should be expected if penetrations are high. The goal of DSM is to augment the energy demanded by customers so that it is economically and operationally efficient. With high penetrations of DER, including EVs operating as vehicle-to-grid (V2G) devices, the impact is sufficient to change the characteristics of a transformer's load profile [27; 28; 29]. Many utility companies utilize load profile characteristics to establish capacity ratings [1; 2]. Therefore, changing a unit's load profile can inherently change its effective rating. The penetration of ES applications is expected to continue to grow [27]. One of the main goals of applying ES applications is to diminish the need to operate less efficient \"peaking\" generators when customer demand is high. In high penetrations, this peak shaving application severely augments the historical load profile during the peaking period [1; 28]. Most energy supplied to ES applications originates from PV systems, residential and utility owned. In high penetrations, PV systems will also augment the historical load profile [3; 4; 28]. PV systems are becoming more popular as home builders and local governments drive to install more net zero homes [30; 31; 32]. Energy generation from PV systems is a function of sunlight, and therefore peak generation occurs from sunrise to sundown. In high penetrations, PV generation reduces the energy consumption during this period, which causes the 24 hr load profile to resemble a \"duck curve\" [5]. Due to economics and system stability, some energy generated by PV systems is stored in ES applications and released during the peaking period. This application further flattens the load profiles experienced by substation transformers. Due to the amount of energy required to charge EVs, many utilities utilize time-of-use rates to influence customers to charge their vehicles during off-peak hours, which occurs between the period of 11 pm and 7 am [33; 34]. This energy shift increases a power transformer's load profile during this period, which is historically low.