You may have never heard the acronym “EVSE” —electric vehicle supply equipment — but you’ve certainly heard of its more common name: electric vehicle charging station. While the two monikers may point at the same object, they carry different connotations. EVSE is more accurate (we’ll explain why momentarily) and tends to be more inclusive of the component parts that make up an EVSE — which probably makes you wonder: What, exactly, goes into an EVSE?
What is EVSE?
Electric Vehicle Supply Equipment (EVSE) is the infrastructure that safely delivers electricity from the grid to an electric vehicle for charging. It includes the hardware, connectors, and communication systems that regulate power flow, ensuring efficient and secure charging.
The National Electronics Manufacturers Association (NEMA) (opens in a new tab) defines EVSEs as:
“[Devices that] provide electric power to the vehicle and use that to recharge the vehicle’s batteries. EVSE systems include the electrical conductors, related equipment, software, and communications protocols that deliver energy efficiently and safely to the vehicle.”
Takeaway: EVSEs aren’t simply plugs you stick into your EV to keep it humming on down the road. Their various components are an important part of what makes them work, and any understanding of EVSEs as a whole requires understanding, on a basic level, those components.
Software and Hardware
Here at EV Connect, we’ve covered much of the software and hardware that goes into an EVSE. Broadly speaking, they’re separated into three main parts: the software (including communications protocols) that make everything run, the enclosure of the charging station and the plug. The software helps make sure everything runs smoothly, and we’ve covered these programs in other articles.
Enclosure
The enclosure can take several forms, ranging from wall mounts to the towers you see by some gas stations. Often, the enclosure also holds the main relay, which switches power to the vehicle on or off, a control module that manages the relay, and a power supply. In some advanced cases, they may have an interface as well.
Plug
It’s the plug that is, sometimes, the most confusing part. Different charging stations use different plug connectors. Usually, which ones you’ll find are decided by both the region you’re in and whether the station is a level 2 or a level 3. But, generally, they all have the same components and pins, if in different arrangements.
As mentioned, however, they come in many different forms. Often these have opaque and arcane names, like the J1772, the Type 2, the CHAdeMO and the Type 2 Combo. As a result, some EVSE manufacturers build charging stations with a wide variety of connector types, and EV owners carry adapters with them…just in case.
How Does EVSE Work?
EVSE works by safely delivering electricity from the grid to an EV’s battery while managing communication between the car and the power source. It ensures charging happens at the correct voltage and current, using built-in safety features and signals to prevent overloads or hazards.
When the charging cable is plugged into the EV, the control module analyzes the connectors on the plug to make sure it’s properly connected, that the car is ready to charge and that the charging station is in working order. If it’s all green, then the main relay powers the cable connected to the car. If the latch on the plug slips, it disables it to prevent arcing. Much of the behind-the-scenes stuff here is managed by software and communications protocols.
What happens next (opens in a new tab) is determined by whether you’re using alternating current (AC) or direct current (DC) charging. Generally speaking, what actually powers the vehicle is DC power.
When you’re using an AC charger (which still make up the majority of connector types), you aren’t actually charging the battery. You’re charging an onboard charging system inside the electric vehicle (EV), which then converts that power to DC electricity and sends it to the battery.
If you’re charging with DC power, this isn’t necessary. Instead, the power goes straight to the car’s battery.
Understandably, DC charging is faster and, in fact, makes up the bulk of higher-end level 3 chargers. The problem is that DC charging devices are also more expensive.
Whichever one you use, the process finishes here. You have a charged battery; you can unplug from the EVSE and go on your merry way.
Codes, Rating Systems and Standards
Codes, rating systems and standards come in two forms where EVSEs are concerned: those aimed at locales in order to encourage and facilitate the installation of EVSEs and those aimed at EVSEs themselves, to ensure interoperability and consistent quality. The former is generally aimed at infrastructure. The latter often includes amperage requirements, quality control for grounding cables and communications protocols to make sure that there is as little friction as possible when charging these vehicles.
To cover all the standards, codes and rating systems relevant to this topic would take a full encyclopedia. It’s important to look at those that govern your locale and the devices you’re interested in to learn more, as they’re often determined by where you are. For a brief but thorough primer, feel free to look through this document (opens in a new tab) by the National Renewable Electricity Laboratory.
Why the EV Charging Industry Must Continue to Develop and Innovate
EVSEs have grown quite a bit, even over the last half decade. But, as it stands, they still have some growing to do. Primarily, this development is needed in the area of speed. Even the fastest chargers can still take a half hour to top off an empty battery. Many drivers — especially in the United States — are already worried about the prospect of being stuck somewhere without a charge or delaying their trip.
For EVs to render fossil fuel vehicles totally obsolete, they’ll need to meet their level of convenience. And to do that, they’ll need to be able to charge a car in a flash.
More than that, continuing development in EVSE technology will, naturally, bring down the prices of those devices that once were the cutting edge. This means that another obstruction to the wide adoption of EV technology — price — will also fade away.
To continue the journey to full adoption of EVs nationwide, innovation can’t only come from the cars themselves. It also needs to come from the devices and software from EV Connect that help charge them. So if we want to move forward, it’s important to pay attention to EVSEs as well.
Frequently Asked Questions about EVSE
What does EVSE stand for?
EVSE stands for Electric Vehicle Supply Equipment. It refers to the infrastructure that delivers electricity from the grid to an electric vehicle, enabling safe and efficient charging.
Is EVSE the same as a charging station?
Not exactly. EVSE is the technical term for the equipment that controls and manages the flow of electricity to the car. A “charging station” is the more common phrase people use, but it usually refers to the entire setup, including the EVSE, connectors, and sometimes the parking space.
What are the main types of EVSE?
EVSE is typically categorized into three levels:
- Level 1: Uses a standard household outlet (120V), slow charging.
- Level 2: Requires a 240V outlet, faster charging, common in homes and public stations.
- DC Fast Charging: Provides rapid charging using direct current, often found along highways.
Why is EVSE important for electric vehicle adoption?
EVSE ensures charging is safe, reliable, and accessible. Without widespread EVSE deployment, drivers face “range anxiety” and limited convenience, which can slow down EV adoption.
Can I install EVSE at home?
Yes. Many EV owners install Level 2 EVSE at home for faster charging. Installation usually requires a licensed electrician and may involve upgrading your electrical panel to handle the extra load.
We’ve partnered with Qmerit (opens in a new tab), North America’s most experienced and recommended provider of implementation solutions for EV charging and other energy transition technologies. Click to get a quote for home EV charger installation (opens in a new tab).
About EV Connect
EV Connect is the comprehensive EV charging platform for companies of all sizes to build, run, and scale their EV charging business. Trusted by CPOs, OEMs, fleets, utilities, and more.
With our industry leading EV charging software and white label EV charging solutions, integrate EV charging into your app and create custom charging solutions that fit your brand perfectly.
Request a quote today and find out why EV Connect is the leading EV charging platform to run your business!
Sources
- National Renewable Energy Laboratory (NREL) – Electric Vehicle Supply Equipment: An Overview of Technical Standards To Support Lao PDR Electric Vehicle Market Development (opens in a new tab)
- Centre for Energy Finance – AC vs DC Charging (opens in a new tab)
- National Electronics Manufacturers Association (NEMA) – Electric Vehicle Supply Equipment/Systems (opens in a new tab)