# Hybrid Energy Routing Approach for Energy Internet
## 1 Introduction
Authors in [10] proposed a Stackelberg game-theoretic approach between the utility company and various prosumers, in which the utility company acts as a leader and announces an energy price, while the prosumers act as followers and adjust their electricity consumption according to the announced price. However, the authors in [11] proposed a contract-theoritic demand response management approach that aims to maximize the profit of both utility grid and prosumers in the SG. Unfortunately, the benefit of the involved prosumers in the FiT systems has been limited, prompting researchers to determine other trading schemes to encourage prosumers to become involved in power trading [12]. In contrast, EI is a peer-to-peer energy sharing system with a bidirectional flow of power and communication. The emergence of P2P distributed energy trading (sharing) in EI provides a new public energy market with new features in the power system. It enables prosumers to trade and share their excess energy (power) with each other directly in peer-to-peer mode without the interaction of a central entity such as a utility company [13]. This peer-to-peer mode of energy exchange gives energy producers and consumers the opportunity to create some financial benefits by selling the excess energy (generally with a lower cost than the cost of a utility company) instead of storing it for future use, which creates some power losses. Additionally, it decreases the consumer's electricity bills and the reliance on the main grid (utility company). As far as we know, due to its complex technologies and infrastructures, there is no standardized architectural model for P2P electrical energy trading and various types of P2P distributed energy trading architectures have been designed by various studies [14; 15; 16; 17]. The expansion of the use of DREs in power generation with their volatility, the transformation of the generation and the injection of power from centralized to distributed manner, the peer-to-peer energy sharing and the power losses during the energy transmission process make the distribution of energy and the balancing of energy supply/demand in EI more difficult. All of these variables gave rise to the key issue of the Energy Internet, which is the energy routing issue. It is known that there is some power losses during energy transmission process between producers and consumers. In order to minimize the power losses and to create efficient energy delivery over the EI, energy routing has been suggested which was inspired by data routing on the Internet. Energy routing is the process that facilitates the transmission of energy between prosumers and consumers situated in different geographic locations with the minimum power transmission losses. The key element of EI and energy routing is the energy router (ER), which is used to route both information and energy flow [18,19]. Current energy systems do not have this capability. However, energy routing in distributed energy systems is more complicated due to integration problems; because power conversion from one type to another may be needed. Energy routing has received considerable attention from the research community in recent years. Current research on this issue includes designing energy routing devices and energy routing algorithms. A number of researchers considered energy routing as data routing and therefore suggested devices and protocols for energy routing. Nonetheless, energy routing criteria are distinct from data routing (see Table 1). The waste packet can be resent in the Internet, which is not possible in EI. In addition, energy routing is demand-driven and the source of the energy is not defined [13]. Furthermore, an energy overflow may cause system devices or even the whole system to crash. Therefore, energy routing has more requirements on safety and reliability than data routing. For that, energy routing protocols are the main field of research for working on EI.