Simplified E-Mobility Layered Model
The picture shows a simplified layered model of E-Mobility. On the Physical Layer the EVs need to be connected to the charging infrastructure to charge. On the Integration Layer the physical components are integrated into the grid, the mobility services supplies roaming and billing functionality (similar to mobile phones) and the regulation & rules defines the rules of the game as well as the international standards required to interwork. The Services Layer is where the services will be implemented (mobility services and energy services).
Physical Layer consists of electric vehicles and the infrastructure required to charge them including capabilities to control them remotely.
Integration Layer is that of intelligently integrating the electric transportation sector with the electric grid through smart-grid standardized communications protocols. This is known as Vehicle Grid Integration (VGI). This layer also consists of roaming & billing functionality as well as rules and regulations to make the energy sector and the transportation sector work in harmony.
Services (Application) Layer consists of services that can be provided by the service providers. This is the application layer where energy services and behind-the-meter services as well as E-Mobility services in general resides.
The Challenge - Renewables & Vehicle-Grid-Integration (VGI)
VGI – The concept of how to intelligently integrate the electric transport system into the electric power system in ways that they work in harmony, which benefit both, and ensuring adequate renewable energy production for clean EVs (green fuel).
Terms typically used:
VGI (Vehicle-Grid-Integration) is the concept of integrating EVs into the electric grid to work in harmony with the grid.
A GIV (Grid-Integrated-Vehicle) is a vehicle that is capable of being integrated in the electric grid.
EVs and EVSEs can be uni-directional (only charging) or bi-directional (charging and discharging).
Bi-directional EV/EVSE pairs are often characterized by the following terms:
The terms V2H or V2B (Vehicle-to-Home/Vehicle-to-Building) are often used to describe that a bi-directional EV can exchange power with a home (or building) in case of grid power blackouts to provide emergency power for typical 3-5 days. Further V2H/V2B can be used to lower the electricity bill by charging from the grid when power is cheap (or charging from solar panels) and discharging to the home when power is expensive typically between 5pm and 8pm. V2H/V2B faces fewer regulatory hurdles.
The V2G (Vehicle-to-Grid) term is often used to describe that aggregated EVs are exchanging bi-directional power flow with the grid to provide grid energy services. V2G often faces a more challenging regulatory environment (meter, net-metering, interconnection rules,…). The infrastructure to support V2G is more expensive than V1G infrastructure, but on the other hand the energy services that can be supported by V2G are more numerous and of substantial higher value.
The V1G term is often used to describe that an EV can only charge energy from the grid (uni-directional power flow), effectively providing lower value grid services than V2G, but facing fewer regulatory hurdles. The majority of EVs currently falls in the V1G category.