## 2 Related Works
The choice of billing mechanism will be influenced by the goals of policymakers, the level of market competition, and the desired balance between stability and flexibility in the energy sector. Nevertheless, today's energy market is driven by more significant needs and higher expectations [31]. Needs and expectations that can no longer be met with traditional financing models. Thus, there is a need for a new billing model capable of providing a higher customer contribution, not only to power generation but also to the management of the grid in general and precise control of prices. This is where the P2P energy trading model comes into play. Conversely, more than a decade ago, a new energy trading model surfaced. The emergence of P2P energy trading can be traced back to the early 2010s. The concept gained momentum as technological advancements, particularly blockchain and smart contracts, offered new possibilities for decentralized energy transactions. However, it was around the mid-to-late 2010s that P2P energy trading gained substantial recognition and saw practical implementations [32; 33]. P2P energy trading has emerged as a promising paradigm in transitioning towards decentralized and sustainable energy systems. The evolution of this concept is ongoing, and its trajectory is influenced by technological advancements, regulatory developments, and the growing awareness of the need for more sustainable energy practices. The P2P energy trading mechanism enables the direct exchange of electrical energy between prosumers and consumers, at a price negotiated by the two parties, without selling this energy to the grid operator first. Therefore, P2P energy trading models eliminate the need for utility companies or grid operators to interfere as intermediaries. P2P energy trading offers several distinct advantages over traditional energy trading models. Primarily, P2P trading enhances the efficiency of energy distribution by enabling direct transactions between prosumers and consumers, effectively reducing intermediary costs and transmission losses. This direct exchange fosters a more dynamic and responsive energy market where prices can more accurately reflect real-time supply and demand conditions. The book in [34] systematically explores distributed economic operation in smart grids, addressing both model-based and model-free approaches to optimize coordination among generation units and loads, while also tackling the challenges of randomness in renewable energy and electric vehicle charging. Additionally, P2P trading promotes the utilization of locally generated renewable energy, thus supporting sustainability and reducing the reliance on centralized, non-renewable energy sources [35]. The increased adoption of renewable energy through P2P networks also contributes to lower greenhouse gas emissions and improves the overall environmental footprint. Moreover, P2P trading can enhance grid resilience by decentralizing energy resources, thereby mitigating the risk of widespread outages. It also empowers consumers by giving them more control over their energy choices and potentially reducing their energy bills through cost-effective transactions. Furthermore, the transparent and automated nature of blockchain-based P2P platforms can streamline administrative processes, reduce fraud, and improve trust among participants. Overall, P2P energy trading presents a promising approach for creating more efficient, sustainable, and consumer-centric energy systems [36; 37]. P2P energy trading designs frequently use game theory approaches [38], auction-based procedures [39], optimization methods [40; 41], and blockchain-based technology. Numerous studies have explored the technical aspects of P2P energy trading, including communication protocols [42], market mechanisms, and grid integration. Smart contracts based on blockchain technology are commonly used to automate transactions and ensure trust and transparency among participants. Other approaches utilize P2P networks or centralized platforms for energy trading.