## 1 Introduction  
With the consensus on global energy and environmental objectives, the development of renewable energy resources is rapidly growing [1]. However, the increase in renewable energy production has led to broad and significant impacts across energy systems [2]. In this regard, demand-side management is a cost-effective way of reducing the energy system burden compared with supply-side management such as unit commitment and bulk generation ramping control [3]. Smart energy communities (SECs) are regional demand-side organizations based on energy integration techniques [4]. They have self-organized energy service providers (SPs) or energy management systems (EMSs) and operate to achieve environmental, social, and economic objectives [5]. Demand-side management such as peak-demand reduction and the load-shifting of the SEC provides the benefit of electricity bill savings and increases the efficiency of the grid [6]. The basic concept of SECs for achieving economic benefits is the sharing of resources. Virtual power plants [7], virtual energy storage systems [6], and community solar power [8] are considered as shared resources. In the case of configuring a large-scale resource and sharing it, a price advantage as the unit price reduction is obtained compared to configuring resources individually [9]. Moreover, increasing the operational resources also enhances the efficiency of systems owing to an improvement in the operational diversity [10]. For an example, if two users operate with resources for which each resource size is one, they can operate at most one, respectively. However, if a sharing operation is performed, operation of 1.5 and 0.5 or 0.5 and 1.5 is possible as needed. However, sharing resources raisesfairness issues regarding how the resources should be shared and the benefits received by each member of the SEC. It is essential to continuously maintain the service of SECs [11]. However, existing SEC research focuses on the benefits of SEC without considering fairness. Therefore, this study examines fairness based on how it should be considered and how it affects the operation of SECs when solar power is used as a shared resource. Several studies on SECs have considered solar communities. Business models and directions for policy makers are outlined in various codes in [12; 13; 14]. [PERSON] et al. showed the cost-effectiveness of community solar considering the solar generation uncertainty [15]. [PERSON] et al. presented the potential of community solar power using geographical information [16]. [PERSON] et al. proposed a hierarchical design optimization method for solar sharing using distributed battery systems [17]. They demonstrated that the sharing process can reduce the required battery capacity and electricity loss. [PERSON] et al. suggested a virtual community-owned solar and storage system for individually controlling the sharing of resources and showed that the individually controlled shared-resource system can achieve the same electricity bill savings as the centralized-controlled shared-resource system [18]. [PERSON] et al. formulated a community solar operation problem as a mixed-integer linear programming problem and experimentally showed that community solar operations can reduce the electricity bill and CO\({}_{2}\) emissions [19]. In fact, the state-of-the-art solar operation techniques reviewed in [20] can be used for community solar operations. However, these techniques do not consider fairness, which is a critical problem in resource sharing. Few studies have been conducted on fairness in resource sharing. [PERSON] et al. formulated the problem of finding an optimal max-min fair allocation of the available energy using mixed-integer linear programming. This problem is minimized by the worst-off user's disutility [21]. In [22], the authors modified the energy allocation problem into a flexibility allocation problem by using the same framework as that in [21].