چارچوب و مدل های کسب و کار نظارتی برای شارژ پلاگین در وسایل نقلیه الکتریکی : زیرساخت ها، عوامل، و روابط تجاری

Electric vehicles (EVs) present efficiency and environmental advantages over conventional transportation. It is expected that in the next decade this technology will progressively penetrate the market. The integration of plug-in electric vehicles in electric power systems poses new challenges in terms of regulation and business models. This paper proposes a conceptual regulatory framework for charging EVs. Two new electricity market agents, the EV charging manager and the EV aggregator, in charge of developing charging infrastructure and providing charging services are introduced. According to that, several charging modes such as EV home charging, public charging on streets, and dedicated charging stations are formulated. Involved market agents and their commercial relationships are analysed in detail. The paper elaborates the opportunities to formulate more sophisticated business models for vehicle-to-grid applications under which the storage capability of EV batteries is used for providing peak power or frequency regulation to support the power system operation. Finally penetration phase dependent policy and regulatory recommendations are given concerning time-of-use pricing, smart meter deployment, stable and simple regulation for reselling energy on private property, roll-out of public charging infrastructure as well as reviewing of grid codes and operational system procedures for interactions between network operators and vehicle aggregators.

The integration of plug-in electric vehicles (EV) in electric power systems poses new technical, economic, policy and regulatory challenges (Galus et al., 2010; Pieltain Fernandez et al., 2011; Momber et al., 2011). Due to energy efficiency and environmental advantages over conventional transportation, the future of EVs seems promising (EPRI & NRDC, 2007). However there are still important technological and economic barriers mainly related with efficient and affordable storage technologies that will hopefully be resolved in the near future (Peterson et al., 2010).1 Regarding the environmental advantages of EVs over conventionally propelled transportation, i.e. fossil fuel dependent internal combustion engines; it has to be kept in mind that they depend on the generation mix of electricity production at the time of charging. In fact timing is one of the reasons for coordinated charging. However, certain studies conclude that, even in rather unlikely but most CO2 intensive scenarios, both annual and cumulative GHG emissions could be reduced significantly, due to a certain electrification level of the car fleet under analysis (Electric Power Research Institute, 2007). It is assumed that agents are profit oriented and would act in response to economic signals such as retail tariffs or market prices for electricity and could then exert different levels of control on the charging of the contracted final EV users. The pricing of externalities caused by electricity production however is assumed to be represented in wholesale energy markets. The European Parliament recently adopted a resolution for the promotion and support of electric vehicles for personal transportation (EU, 2010). In this resolution different actions are proposed in order to achieve a single European EV market. Among those actions the call for international or at least European standardization of charging infrastructures and technologies, including smart grids, with open communication standards, should be highlighted. The currently perceived purchase premiums compared to internal combustion engines are widely being discussed and a multitude of different policy schemes to foster EV adoption is evaluated. A comparative study shows that from a user perspective one time support at the initial investment is highly appreciated. However, recurring instruments like an annual tax benefit are more effective yet usually smaller in volume (Kley et al., 2010a). In addition to technological developments and policy measures, regulatory issues related to investment and deployment of the required infrastructure need to be formulated and adequately solved. Coherently, there is a need for discussing how and which agents should be authorized to provide EV charging and pricing of those services, as well as how EV storage capability could be appropriately marketed to provide vehicle-to-grid (V2G) services (Kempton and Tomic, 2005). However, an accurate calculation of the benefits is a complex task in order not to misunderstand or overstate the potential (Dallinger et al., 2011; Andersson et al., 2010). Therefore, still many questions remain to be answered within a consistent regulatory framework considering rules and players in existing electricity markets. Setting the structure for a cost-effective development and deployment of the necessary charging infrastructures is a difficult task given the early stage of the industry. Predicting all possible occurrence of economically viable and socially desirable infrastructure development in accordance with smart grid requirements poses a great challenge for decision makers. It would involve determining the financing structure to be collective or private. Investment costs could be socialised among electricity consumers or more generally among all tax payers. Alternatively they could be recovered through EV user payments only. Furthermore it is yet unclear which agents should be responsible for developing them as well as whether the business would be bound to strong monopolistic regulation or characterized by competitive components. None of these questions is answered in Kley et al. (2011). Depending on the intended outcome, the charging infrastructure could be considered a fully regulated monopoly, as transmission and distribution grids are, or a corporate entity allowed owning and deploying charging infrastructure. All of the above raised issues can be extended to specific infrastructure capable of using EV storage for grid service provision V2G as peak power or ancillary services, frequency regulation and power reserves. However, V2G contains yet another challenge. The conditions to incentivize vehicle owners to adopt direct charging management mechanisms and yield control over the battery system are yet to be found Pecas Lopes et al. (2010). According to that, a regulatory framework needs to maintain the utility's obligation to provide reliable electric service balanced with a vehicle owner's desire to sustain control in case of personal need. As electricity for charging EVs is used for transportation, there are various controversial arguments for a price differentiation from other electricity consumption, for instance including taxes for development of transportation infrastructure or by the contrary giving it subsidies because of carbon emissions reduction relative to traditional internal combustion propulsion systems for transportation. As an example of these issues, in California, the Public Utilities Commission has opened a rulemaking process, in which a number of issues are proposed for consultation with stakeholders. It is yet to be determined (i) how to implement obligatory variable tariffs, (ii) legal status of electricity resellers, (iii) incentive creation for users to adopt remote charge control of valuable2 batteries, and (iv) allocation and recovery of investment in infrastructure in a fair non-discriminatory framework (CPUC, 2010a). Furthermore, there exists an intense discussion about critical metering policies in terms of metering arrangements (single, sub- and separate metering) and their implications on cost, installation time, and billing flexibility (CPUCb, 2010b). In this paper, a conceptual framework is developed in order to provide the basis for giving an answer to the previous main issues of regulating future large scale EV integration. The regulatory framework for the organization of the European internal electricity market (EC, 2009) is taken as reference framework in which concepts must function. However, many of the proposed concepts remain partially valid for other markets or regulatory structures. Further on, different charging modes for providing energy and V2G services are identified and presented in detail. The paper is organized as follows. Section 2 recapitulates each role of the existing involved agents in the electricity sector. Consecutively, the new agents related to the business of charging EVs are introduced to the reader. Section 3 introduces definitions of grid and charging infrastructures. Section 4 identifies metering, communication and control equipment for charging EVs. In Section 5, charging modes associated with charging at private parking sites as well as for public use are defined. Different basic charging modes, from electricity supply at home to public and private3 charging stations are proposed in Section 6, while Section 7 provides alternative solutions of the basic variants. The same type of business models are revisited for providing V2G services in Section 8. Finally, conclusions and some policy recommendations are given in Section 9.

In this paper regulatory issues for integration of plug-in electric vehicles in the electricity sector have been identified and several proposals regarding the definition of new agents, charging infrastructure ownership and development, as well as future EV charging modes with commercial relationships between involved agents have been made. In this proposal a new agent called the EV charging manager or the EV charging point manager (CPM) has been introduced. CPMs are in charge of developing charging infrastructure in privately owned parking areas and charging EVs acting as a final customer in the market. In public areas, it has been proposed that the local DSO will develop the costly charging infrastructure providing public access to EV owners. EV suppliers will have contracts with EV owners for selling charging services in public parking areas. Furthermore, the role of EV aggregators for pooling multiple EV owners for providing V2G services to the ISO or TSO is a relevant new agent within this proposal. CPMs and EV supplier-aggregators are considered qualified and authorized market agents who provide EV charging services and V2G services on a competitive basis. Table 1 summarizes the three main elaborated proposals with the criteria concerning agents involved, contracts, programming charge control, and CP developing entity.22 EV charging modes have been formulated for EV charging at home, at public parking areas and for dedicated charging stations. Infrastructure costs and charging points requirements in terms of communications and control varied significantly depending on the aforementioned options. For instance, charging at home during nights could be a generalized alternative with minimum infrastructure costs. On the other hand, fast charging at dedicated charging stations would involve higher costs. Therefore, from a regulatory point of view, the integration of EV in electric power systems can be foreseen in a three phased process. 9.1. Key actors and business models In the near term, EV home charging and charging in private areas, such as shopping and office parking areas will be the most probable scenario with a relatively low penetration of EV. In this initial phase, EV charging could be based on time-of-use prices, in which hours of low system demand and little network utilization are less expensive. For implementing multiple rate tariffs for residential and other low voltage customers with EVs, installation of smart meters as an interface with the electricity utility company is highly recommended. In this phase it is required to allocate the charging periods within those hours with low prices by implementing simplified approaches of given control concepts. Moreover in this initial phase, legislation should develop the figure of charging point manager acting on private property with public access allowed to resell energy for EV charging as a final customer in the electricity market. Current legislation only allows retailers to buy and sell energy in the market. To foster the uptake of these new agents and increase the number of charging options to the final user, the regulation should keep the technical requirements and financial liabilities for CPMs as simple as possible in comparison to the ones required currently for retailers. In the second phase, with high EV sales uptake a massive deployment of smart charging as well as the development of more public-street charging infrastructures is recommended. Charging infrastructures in public sites would be more expensive, DSOs, today in charge of developing the electricity distribution grid, are in the most favourable position to own and operate those charging public points. Legislation should ensure a stable regulatory framework to recover the associated investment expenditures. On the other hand, in this second phase, the emergence of a new business model called EV supplier-aggregator is foreseen, contracting high numbers of EV and exert a higher level of control over the charge. The aggregator shall be responsible for a system favourable load management and hedging risks in electricity markets. To assure the smooth functioning of the system operation, the aggregator should also respond to needs coming from network operators, in order to cooperate as well as solve operational and/or security problems in the grid. There is still a need for more quantitative research in order to assess costs and benefits and added value of those new agents. As it has been said, the implementation of control concepts is crucial for the success of this type of new business. Merely in the third phase, the rather long term development stage of EV integration, vehicle fleets participating in the provision of ancillary and balancing services procured by transmission system operators or DSOs for local requirements would be a reality. It is in this phase where EV supplier/aggregators specialized in those services will develop. If this is the case, the implementation of the most sophisticated control and measurement version of control concepts will be required. 9.2. Market design and network regulation From the developed framework, conclusions and recommendations can also be drawn about market design and network regulation. Methodologies to approve and accept DSOs' capital as well as operational expenditures when calculating allowed revenues should be rephrased to include new installations for public charging infrastructure. The installation of smart meters for final customers as potential EV users connected to a low voltage grid should be made compulsory. In this way those customers will have access to time-of-use tariffs offered by retailers, instead of staying under a flat regulated tariff (which still exist at least in some EU countries). In addition, load profiles for residential customers with EVs in the retail market would be adequately considered. Future controlled charging or vehicle-to-grid should be explicitly considered by system operators in order to postpone or reduce network investments and make use of EV capability. That would require a review of grid codes and system operational procedures. 9.3. Outlook Further models for including the provision of V2G services are by far the most sophisticated in terms of technology requirements and commercial relationships between involved agents. Benefits and costs should be carefully evaluated in future research. It is strongly recommended that supply contracts for CPMs and EV owners would be based on cost-reflective network charges and energy market prices, i.e. with demand charges and ToU or hourly price differentiation. The installation of smart meters is necessary to facilitate the implementation of time differentiate rates even in case of home charging applications. In the proposed framework, EV suppliers would be free to design tariffs and set EV charging rates being considered competitive businesses. It is expected that charging infrastructure costs could be recovered, and electricity procurement costs passed on to the final customer, while obtaining a business margin. Despite considering CPMs and EVSAs competitive businesses, authorization and registration for such activity should be controlled by regulatory authorities as it is practiced for other suppliers, forming a part of the electricity market. If due to energy or transportation policies it is decided to charge or to subsidize EV electricity consumption, these agents, CPM and EVSAs could be the ones in charge of collecting taxes or applying discounts when billing EV charging services. In the same manner, environmental policies on carbon emission trading and pricing could be implemented by controlling the amount of electricity used for charging EVs through those agents. Alternatively, taxes or subsidies could be directly applied to each EV owner according to its energy consumption measured by its on-board meter.