The world of electric vehicles is brimming with acronyms, and it’s not always easy to keep them all straight. While “EV” itself is pretty well established at this point, there are plenty of people who aren’t familiar with terms like BEV, HEV, and PHEV—and now a new member has joined the club: EREV. What do all these letters stand for? Is an EREV really a new thing or just a PHEV with better range? Let’s dive in and figure out what’s going on…
BEVs, HEVs, PHEVs—What’s the Difference?
Let’s start by explaining some of the older and more common initials so that we all understand our terms. The term EV means electrified vehicle. While that might seem straightforward to some, it’s actually pretty vague. Does the vehicle need to run entirely on electricity or only partially? How is that electricity generated? Because of these questions, subcategories have been created in order to differentiate between the various types of electrified vehicles, with the simple “EV” acting as an umbrella term that encompasses all of these more specific labels.
BEVs (battery electric vehicles) are what most people probably think of when they think of EVs. These cars, trucks, SUVs, and vans run entirely on electric power provided by a large battery pack (or possibly multiple battery packs). They can be charged either at home or at public charging stations in order to charge the battery and get more power.
HEVs (hybrid electric vehicles) are traditional hybrids. These vehicles won’t have a charging port at all and, therefore, can’t be plugged into the power grid in order to add range. Instead, they have batteries that are recharged by a process called regenerative braking. Basically, whenever you brake any vehicle, the brakes generate friction and expend energy as heat. Regenerative braking recaptures some of this energy and uses it to charge the battery. This isn’t unique to HEVs (PHEVs, BEVs, and EREVs also use it), and it’s the reason why EVs tend to have better fuel economy in city driving (where there’s more braking), while gas-powered cars typically have better fuel economy on the highway.
A PHEV (plug-in hybrid electric vehicle) is basically a mix between a BEV and an HEV. PHEVs still have gas engines, but they also have powerful electric motors and large battery packs. The batteries are powered by both regenerative braking and plugging into a charging station. While HEVs can typically only run on electric power alone for short distances at low speeds, PHEVs usually have an electric-only range that allows you to drive for anywhere from 20 to 50 miles without using the gas engine at all. While that range is enough for short trips around town or the average commute, it’s nowhere near the hundreds of miles of all-electric range offered by BEVs. If only there were something in the middle…
Enter the Extended Range EV
That’s where the EREV (extended-range electric vehicle) enters the picture. Once, the PHEV emerged as a middle ground between HEVs and BEVs. Now, the EREV is slotting itself between PHEVs and BEVs, letting drivers get even closer to full electrification without quite needing to give up having gasoline as a backup power source in case charging infrastructure is hard to come by. But does this type of vehicle actually deserve its own term, or is it just a PHEV with a more powerful battery and, therefore, a larger all-electric range?
It turns out there is a real difference in the underlying technology. Basically, a PHEV can be powered either by the battery or by the gas motor. When your battery power runs out, the engine takes over and powers the car just like an engine would for a car that has no battery pack at all. That’s not the case for EREVs. Instead, the drivetrain is powered entirely by electric motors that get their power from a battery pack that’s larger than what you’ll find in the typical PHEV but smaller than the average BEV battery. When the battery runs out of power, the engine doesn’t take over powering the vehicle. Instead, the engine acts as a generator that charges the battery.
What Are the Benefits of EREVs?
While this system might seem strange if you’re hearing about it for the first time, it does have a lot of upsides. In fact, a similar concept (known as diesel-electrics) has been powering freight trains for decades. One advantage it has over PHEVs is that it simplifies the mechanics of the system.
In a PHEV, both the electric motors and the gas engine need to be able to directly power the car, meaning that both need to be tuned to deliver good driving dynamics, and there needs to be a system that determines when to switch power from one source to the other. With an EREV, only the motors directly power the car, so the engine can just focus on creating energy and not worry about things like throttle response. This also helps with efficiency since the engine can be optimized to run at an RPM range that’s good for charging the battery and doesn’t need to change gears and lose power to the transmission.
EREVs also offer some advantages over BEVs. One of the biggest concerns potential EV drivers have is getting stuck with a dead battery because there aren’t enough chargers around, and one of the biggest frustrations is how long charging takes compared to filling a tank with gas. With an EREV, you’re driving a portable gas-powered generator that gives you extra power when you run out of battery charge and can be refilled in mere moments at any gas station. This is especially helpful for large SUVs and trucks that offer towing capability since towing is always going to decrease efficiency and lower an EV’s range. With a gas-powered backup on hand, that’s not as big of a danger or inconvenience.
Can I Buy an EREV Today?
At the time of writing, there are no new EREVs available in the United States. That’s set to change when the 2025 Ram 1500 Ramcharger makes its debut. Ram is already boasting that this model will be the “world’s first-ever range-extended full-size electric pickup truck” and estimates that it will be able to tow 14,000 lbs. Other automakers (including Ford, Nissan, and Hyundai) have also publicly stated that they’re looking into using EREV technology for future vehicles. These are likely to be other large vehicles, like full-size pickups and three-row SUVs.
It’s unclear whether this setup will be used for smaller SUVs or even cars down the road. Because smaller vehicles can more easily offer a high range with a BEV setup and generally aren’t expected to tow heavy trailers, which drastically affect range, they aren’t the best candidates for the EREV treatment. Still, it’s always hard to predict the future, and if this technology takes off, there’s no telling how widespread it might become. It’s already been used to power a variety of vehicles in China, from three-row SUVs and off-road Jeep-like vehicles to compact premium SUVs that would easily fit in on the American market. As the tech makes its way to America, we’ll certainly have to keep an eye on it.
Bridging the Gap for Would-Be EV Drivers
Gas stations are everywhere, loading up a tank is quick, and drivers are familiar with the process of keeping a gas-powered car fueled and ready to go. It’s been tough getting EV infrastructure to a point where it’s competitive with this consumer-friendly system. Certainly, we’ve come a long way. Public charging stations have been popping up in parking lots across the country, DC fast charging offers road trippers a way to fuel up fast, and Level 2 home-charging stations are becoming increasingly common.
But until the electric infrastructure feels safe and familiar for the majority of drivers, including those who don’t live in urban areas where charging stations are more common, it’s going to be important to have options that bridge the gap for people who want to drive more sustainably but can’t fully rely on electric power. EREVs are an innovative solution, and it will definitely be exciting to see whether they can get a strong foothold in the US. They certainly have the potential to change driving habits for the better and help us on the road to a greener future.
