A-Z of EV Smart Charging - a Glossary
Over the past few years, Electric vehicles (EVs) have garnered global acceptance and usage at an astonishing pace. The quality growth in the EV market coincides with a time when the world is seeking newer methods of sustaining its electric grids. These methods include, although not limited to, grid decentralisation and the evolution of EV charging— EV smart charging.
The prevalence of EVs in the global automobile scene puts a strain on grids because of their high dependence on the grid. To balance energy supply and demand and prevent grid collapse, most countries now adopt smart EV charging.
As an EV owner or fleet manager, it’s important to understand the necessary aspects of EV smart charging. By familiarising yourself with the terminology associated with EV smart charging, as seen below, it not only becomes easier to manage your vehicle but also communicate effectively with other members of the EV community.
The current stored in a typical EV battery is the direct current (DC), whereas the current that comes from the grid is the alternating current (AC). Therefore, a conversion must occur inside or outside the EV to reconcile these two distinct currents. When the conversion occurs in the EV, the process is called AC charging.
In AC charging, AC flows from the AC charger into the EV and is converted by the onboarding charger to DC, which then charges the EV battery.
Active Load Management (ALM)
When an EV is connected to charging infrastructure, it does not compete with any other vehicle and, as such, gets maximum charging. However, with multiple EVs comes the need to satisfy all the EVs being charged. Sometimes this creates, at best, an imbalance and, at worst, a shutdown of electrical facilities connected to the infrastructure.
ALM is used to prevent these cases. With ALM, buildings can easily communicate with EV charging stations to evenly distribute the available load to the EVs without straining the grid or the building.
BEVs are the only class of EVs that run solely on battery-stored electricity. Their batteries, predominantly Lithium-ion (Li-ion) batteries, which power the vehicle and release net-zero carbon emissions, are easily rechargeable at charge points.
A charge point, also referred to as electric vehicle supply equipment (EVSE), is one of the components that make up the entire EV charging facility.
A charge point transmits electricity to an EV via one or more connectors—only one of which can be active at a time. Using a gas station as an analogy, a charge point can be likened to a fueling hose that receives power directly from the gas pump and delivers it into the vehicle through the nozzle— equivalent to a charging outlet or connector in the case of EVs.
Charge Point Operator (CPO)
A CPO is equivalent to the manager of a gas station. They are responsible for installing and maintaining a charging pool—the facility that houses and operates multiple charging stations. Their work description includes purchase and installation of hardware such as charging stations, maintenance of network connection, price fixing for facility use, and management of the connection to eMobility service providers (eMSP).
Where a charge point functions similarly to a fueling hose, a charging station can be likened to a gas pump with a user interface that connects the gas reservoir to the vehicle. A charging station serves as the intermediary between the grid and the EV, regulating the amount of electricity, displaying the price for the EV owners and CPOs to see, and serving as a vital tool in active load management.
A charging station, just like the gas pump, can have multiple hoses and more than one charge point attached to it, each of which can serve only one EV at a time.
Charging Station Management System (CSMS)
CSMS is a collection of tools that work together to assist charge point operators and enable them to manage EV charging pools better. These systems include technology such as EV smart charging software that makes smart charging a possibility and a simplified process.
Combined Charging System (CCS)
The CCS is a rapid charging method that has grown in popularity in Europe and North America over the past few years. It was developed in response to the slow Type 2 Connector (See below).
EVs are multiplying rapidly, and the need for faster-charging options is rising correspondingly. The CCS connector combines the Type 2 Connector with two other DC power lines running at significantly higher voltages than the Type 2 Connector. This combination boosts EV charging beyond the normal experience.
Like smartphone charging, every EV charging process requires two end connectors: one plug into the charge point and the other into the EV socket.
The charge speed that an EV gets is mostly reliant on the types of connectors used.
Visit here to learn more about the different types of connectors and their suitability for your EV.
DC charging is simply the opposite of AC charging. The difference between them is in the host of current conversion. In AC charging, the AC is converted to DC in the onboard charger installed inside the EV. DC charging, on the other hand, employs the service of a charge point that can convert AC to DC before transmitting the current into the EV.
One of the central ideas of EV smart charging is effective grid management through demand response.
Demand response happens when energy consumers and grid operators communicate with one another for optimal usage and transfer of electricity. With smart charging, EV owners can remotely manage how and when their EVs get charged. By doing so, they get to charge during off-peak demand hours, thereby putting less strain on the grid.
Distribution Network Operator (DNO)
The DNO is the mediator between the grid and a utility, providing electricity to EV charging pools. Therefore, the CPO cannot implement necessary installations without contacting the DNO—responsible for the amount and speed of electricity distributions.
The EV charge point grant is a scheme by the UK government to fund up to 75% of the total costs of installing EV smart charge points in domestic infrastructures across the UK.
Electric Vehicle Service Provider (ESVP)
EVSPs provide point-to-point EV charging by handling both charging station performances and driver experience.
They are bodies that manage multiple affairs of EV charging, such as public charging, residential charging, fleet depots, workplace charging, etc., to give the best experience to both CPOs and EV owners.
eMobility Service Providers (eMSPs)
eMSPs can be said to be the other side of CPOs. Where CPOs cater to the well-being of EV charging pools, eMSPs are more driver-oriented. Their services include:
- Providing ample information regarding charging stations and navigating them.
- Suggesting suitable charge points.
- Helping drivers adjust their charge times.
Contrary to popular misconception, an EV charger is not any of the charging stations or charge points but rather a device built inside the EV. In AC charging, for instance, the EV charger, also called the onboarding charger, is what receives the AC and converts it to DC before finally topping up the vehicle’s battery level.
An EV driver drives an EV and engages in residential, public, and workplace charging.
Home charging, just as the name implies, is the process of charging an EV using facilities installed at home. However, home charging has different levels to it, namely: Level 1 and Level 2.
Level 1 DV charging is slower, delivering a standard household exit current at 110 or 120 volts. Level 2, however, doubles Level 1’s outlet current at 220 or 240 volts or higher.
Home Energy Management System (HEMS)
Home charging requires that EV charging facilities share energy with other household appliances. When not managed well, this might disturb the home’s energy usage. The effective incorporation of harmony between household appliances and DV charging features concerning the grid is HEMS.
HEMS has two kinds of load management: static and dynamic. Static load management prioritises energy required by EV charging facilities, compromising other appliances. Dynamic load management is similar to ALM in that it considers every item that needs to be charged and then spreads the load evenly.
ISO 15118 is an international standard established to streamline the digital communication agreements that EVs and charging stations must follow when recharging.
Visit here to learn more about the protocols.
In EV charging, like in the case of smartphone charging, there are levels that dictate the speed and quality of charging.
Level 1 charging, the slowest of them all, on a full charge, offers three to five miles an hour. This type of charging is done by plugging your EV into your regular wall charge point.
With Level 2 charging, the EV, on the maximum charge, is guaranteed approximately 75 miles of range.
Level 3 charging gives an EV a maximum range of 298 miles.
Li-ion is the predominant type of battery used in EVs because of its high energy per unit mass and power-to-weight ratio.
Miles Per Kilowatt-Hour (Miles per kWh)
The miles per kWh of an EV are equivalent to miles per gallon used for internal combustion engine vehicles (ICEVs). The efficiency ratio tells an EV driver how many miles their vehicle can go on one kWh of electricity.
If an EV’s battery has a capacity of 60kWh and an efficiency rating of 3 miles per kWh, it can go 180 miles on a full charge.
The electric motor, alongside the battery, makes an EV what it is. Motors are powered by current from the battery, after which they propel the EV.
A good automotive motor must have a high starting torque, a high power density, and high efficiency. The most prominent motors in EVs include DC series motors, brushless DC motors, permanent magnet synchronous motors, switched reluctance motors, and three-phase AC induction motors.
Off-peak hours are periods when demand from the grid drops significantly, usually at night. When EV owners charge their EVs around this period, it is called off-peak charging.
By leveraging off-peak charging, EV owners not only save on charging costs but also relieve the grid of additional load that it would have otherwise borne during peak-demand hours.
OCA is a global chain of public and private EV infrastructure owners with a common goal of promoting open standards through two distinct protocols:
- Open Charge Point Protocol (OCPP) includes EV charging obligations such as added smart charging functionalities, security, improved transaction handling, etc.
- Open Smart Charging Protocol (OSCP)—which makes and informs grid operators of predictions regarding available local capacity for production and generation, provides fitting production and generation of flexibility resources to grid capacity, etc.
Plug and Charge (P&C)
P&C is a technological idea initiated by ISO 15118 (See above). The initiative aims to make EV charging more user-friendly for EV drivers.
It is an automation process that collects driver data as soon as they plug in their vehicle. With P&C, drivers need no longer repeatedly make payments, scan barcodes, manually submit their EV identity information, etc.
Plug-in Hybrid Electric Vehicle (PHEV)
PHEVs are a kind of EVs that combine both a battery and an internal combustion engine to run. The vehicle starts by running on the battery and then automatically switches to the ICE.
PHEVs’ batteries can be charged in three ways:
- At charging stations—either AC charging or DC charging.
- Regenerative braking—energy converted from the reversed force due to braking.
- Fuel-generated charging—the fuel in the ICE is used to generate enough electricity to charge the battery.
Public charging, as opposed to home and workplace charging, is not exclusive. Because of their easy accessibility, public charging stations reduce the need for EVs, such as PHEVs, to switch to ICE during driving.
Radio Frequency Identification (RFID)
RFID is the unique identity possessed by EVs and EV drivers and is used for identification and payment for charging. EV drivers usually hold RFID cards to facilitate payment for charging sessions.
However, this method tends to get tedious and sometimes overwhelming due to the driver’s forgetfulness, card loss, or other forms of a mishap. This redundancy is one of the challenges the Plug and Charge initiative (See above) aims to solve.
An EV’s range consists of the miles it can travel on a full charge. The factors that affect the range of an EV vary from physical to behavioural: tyres, weather, driver’s style, etc.
Range anxiety is the feeling that EV drivers get when they perceive a low battery and they can’t find alternatives in sight. Range anxiety is one of the major factors behind people’s refusal to switch to EVs.
Range Per Hour (RPH)
RPH is how EV chargers are rated. With the knowledge of their EV’s RPH, drivers can project how far it can go.
RPH is mostly determined by the capacity of the charging station, the EV’s efficiency, and the EV’s state of charge.
Roaming Network Operator (RNO)
RNOs provide essential services to both CPOs and EV drivers. Roaming enables EV drivers to use any charging facility they can access without uniquely identifying as a customer of said facility or station. It brings about fluidity in driver-station engagement.
State of Charge (SoC)
An EV’s SoC measures the amount of electricity currently available in its battery. The SoC is similar to the fuel gauge in an ICEV, preparing the EV driver for the next line of action.
This is what happens when drivers leverage the time their EVs are parked to keep them charged as opposed to leaving the battery to be emptied of its power before recharging.
Type 1 and Type 2 Plugs
Type 1 plugs or connectors provide fast charging at an output of between 3.7kW and 7.5kW AC, yielding an RPH of 12.5 to 25 miles per hour.
The Type 2 plugs, on the other hand, offer faster charging between 22kW and 43kW, yielding an RPH of between 30 and 90 miles per hour.
Vehicle-to-Grid (V2G) Charging
V2G is smart charging technology that enables EV batteries to return inactive electricity to the grid for better grid management.