# Proxy Signature-Based Management Model of Sharing Energy Storage in Blockchain Environment
## 2 SES and Its Management Model
### Management Model of SES  
The essence of a sharing economy is the separation of ownership and use rights of goods, and temporary transfer of the use rights. Therefore, an SES market is necessary to provide a platform for matching, bidding and trading between supply and demand sides. Suppliers need to quantify and commercialize idle energy storage resources, which will be traded to demanders in the market. Demanders purchase the use rights of idle energy storage resources from the market and utilize the resources in real time or in a specified period of time. It is worth mentioning that the SES market can rely on the existing power market and its platform or build a special market where only the use rights of SES are traded. All the owners of idle energy storage resources constitute the supply side of the SES market. According to the scale of resources, cost and management ability, the management model of SES can be classified into two categories: a self-operation model and principal-agent model. * Self-operation model: In this model, the owners of idle energy storage resources directly participate in the market as an independent market entity. They are personally responsible for the market behaviors including bidding or pricing, credit behavior, signing and executing contracts, and so on. Moreover, the cost of labor and equipment, the obligations of market entities as well as the market risk are borne by the owners. Meanwhile, they will enjoy all the profits from the transactions of SES. Based on the above characteristics, this model is more suitable for the owners with large-scale energy storage facilities. Firstly, they possess sufficient technicians and information resources to maintain the competitiveness in the market. Moreover, the energy storage resources controlled by them can meet the market access conditions for energy storage according to the operating rules of the power market in China, which could obtain better profit prospects from it. * Principal-agent model: In this model, the owners of energy storage resources delegate the agents to participate in the market on their behalf. The agents can exercise the rights of the principals in the market and complete the market behaviors. On the basis of the delegated scope, there are two types of principal-agent model--i.e., full delegation and partial delegation. The ownership of energy storage resources belongs to the owners, but the management rights, including operation, maintenance, personnel management and market transactions, are transferred to the agents in the full delegation relationship. In this paper, partial delegation only refers to the delegation of transaction rights to the agents. The full delegation model has been applied in some railway enterprises in China [29]; however, the partial delegation model is common in the financial field. On the other hand, the one-to-one model and many-to-one model are also two types of principal-agent model according to the number and relationship of principals and agents. The difference between these two models is that the resources controlled by an independent market entity from one owner or many owners. For SES, the agents in the principal-agent model can be defined as sharing energy storage operators (SESOs). Compared with most of the owners, the advantages of SESOs include more professional and experienced market traders, superior information systems and more improved databases. Moreover, the small-scale idle energy storage resources can be aggregated by SESOs to meet the market access conditions. Through the agent of SESOs, the owners reduce expenditures on management, labor, equipment and transaction costs, and may obtain more profits from the market than independent operation. SESOs charge owners who delegate them a certain percentage of management fees. Based on the above characteristics, the principal-agent model is more suitable for the owners with small-scale energy storage facilities, as well as the owners who lack the experience and ability to trade in the market.