## 1 Introduction
On the other hand, through the past decade, the energy market has witnessed a digital revolution driven by the need for a more intelligent, more efficient, more resilient, and more flexible grid, as well as by new client requirements. Under the influence of a global trend of digital transformation, the energy sector was not exempt from the impact of disrupting emerging technologies, such as the Internet of Things (IoT), Artificial Intelligence (AI), blockchain, and Big Data, that affected the electrical grid's complete value chain, from generation to transportation and finally to distribution [12]. Furthermore, new energy apprehensions, such as energy democracy and energy poverty [13; 14], emerged in response to new socio-economic challenges. In addition, prosumers were requesting higher involvement and transparency in managing their energy consumption [15]. Accordingly, in response to a need for higher digitalization and a more user-centric energy system, the energy market is once again propelled to change. This article is part of a larger project that proposes a new blockchain-based decentralized electric grid model. This new model, defined as Energy 4.0 (Figure 1), is based on P2P energy trading. P2P energy trading offers a new multidirectional decentralized model for selling and buying energy. Contrary to the previously existing model, the P2P energy trading model is considered an interdependent model (Figure 2), where the energy trading is not monopolized by the grid operator or the utility company but offers households, businesses, or even communities to be both consumers and producers of energy while trading energy among each other. However, this concept requires a digital platform capable of connecting peer nodes without intermediaries and securing and managing transactions in real time while leveragingtransparency, immutability, and anonymity. A need that is best served using blockchain technology. Blockchain is a digital data management solution based on distributed ledger technology (DLT). It allows transactions to be securely recorded and anonymously shared via a network of computers [16]. Blockchain achieved its fame through the cryptocurrency Bitcoin, though its uses go far beyond digital currencies. Blockchain-based P2P energy trading is one of these applications. P2P energy trade on the blockchain is an innovative use of blockchain technology in the energy industry. This concept leverages blockchain's decentralized and transparent nature to enable direct transactions between energy producers and consumers within a network. This article sheds light on the advantages of blockchain-based P2P energy trading models as an incentive mechanism for a higher implementation and integration of DERs. The main contribution of this work is that it offers a direct comparison between the P2P energy trading mechanism, NEM, and FiT in terms of rentability for prosumers using different key performance indicators (KPIs) such as the total amount of unremunerated excess energy and financial revenue from the traded energy. To validate the competitiveness of the P2P energy trading model as a new billing model for DERs, a rural microgrid composed of two prosumers and four consumers was considered. The microgrid was tested under different scenarios and billing models, and the results were analyzed to evaluate the most adequate model. Additionally, sensitivity and feasibility analyses were performed to complete the image. In Section 2 of this article, a review and evaluation of the existing billing models and related works is conducted. Afterward, the blockchain-based P2P energy trading model is introduced. In Section 4, our choice of a rural microgrid is justified, and our selected microgrid is presented in addition to the simulation algorithm and flow chart. In Section 5, the simulation results are presented and analyzed, and in Section 6, a financial study and sensitivity analysis are conducted.