A long-range EV has a power unit called a range extender that charges the battery when it runs low, giving the car a boost. The range extender may be a combustion engine or fuel cell. Long-range batteries ease the fears of first-time electric vehicle owners since they can travel farther without worrying about finding a charging station. Here’s the science behind the spectacle.
What Are Extended-Range Electric Vehicles?
There are many names for EVs that have an extended-range battery, including extended-range electric vehicles (EREVs), range-extended battery-electric vehicles (BEVx), and range-extended electric vehicles (REEVs). These are simply different ways of describing the same type of car. How do these vehicles compare to hybrids, ICE cars, and traditional EVs?
Similarities Between EREVs and Hybrids
Many confuse EREVs with hybrids because they both have an internal combustion engine and an electric battery. They both run purely on electricity and have a plug that lets drivers power them at home or a charging station.
They also usually have a gas tank to power a combustion engine — called the range extender — as a backup to the electric battery, but sometimes as the primary power source. Occasionally, the range extender is a hydrogen fuel cell instead of a combustion engine. That means the car produces no harmful emissions at all.
Classic electric cars only have batteries and ICE cars only have combustion engines. Therefore, both EREVs and hybrids fall into the category of vehicles with two forms of power generation. They may skew more electric or gas-powered, but they always have both options.
The Difference Between EREVs and Hybrids
There’s a key mechanical distinction between the two types of vehicles. In hybrid cars, the combustion engine is connected to the wheels. That means the gas-powered engine physically turns the wheels as it runs.
The combustion engine or fuel cell is connected to an alternator in an EV with a long-range battery. When the electric battery falls below a certain charge threshold, the range extender kicks in and powers the alternator, which recharges the battery.
The car drives on electric battery power, then switches to gas or hydrogen fuel as a backup. The fuel powers the battery rather than the wheels. That’s the science behind an extended-range battery.
For example, the BMW i3 can drive 126 to 153 miles on its electric battery alone. Once that gives out, the gas-powered engine supplements the battery with an additional 50 miles of range. The driver could also stop and recharge the car before the battery is drained, forgoing the use of fossil fuels entirely.
The Advantages of an Extended-Range Battery EV
Why are EREVs so popular compared to other types of cars?
Excellent Fuel Economy
EVs featuring a long-range battery connected to a range extender get great fuel economy. Because the engine isn’t attached to the wheels and doesn’t have to generate as much power, it can be smaller, simpler, and lighter in weight than a traditional car engine.
The engine works optimally because it isn’t subjected to accelerating and decelerating based on how fast the car goes. It always operates in a controlled environment.
A Quiet Ride
An EREV’s engine doesn’t vibrate, offering a smooth ride. Some drivers find the lack of engine noise at low speeds unsettling, but that’s because most people are still used to hearing a loud internal combustion engine. When an extended-range EV reaches higher rates, drivers will hear the same wind and road noises as they would in a car with an internal combustion engine.
Some governments have also mandated that newer EVs make a low humming sound to alert pedestrians. Manufacturers and mechanics have even retrofitted older electric vehicles with warning sounds to comply with these laws. However, compared to an ICE vehicle, electric cars are very quiet.
EREVs can drive a considerable distance on purely electric power before the range extender kicks in, producing fewer emissions than a traditional car. In fact, hydrogen fuel cell EREVs don’t use gasoline at all. That’s a crucial component of reducing the effects of climate change.
Passenger vehicles emitted around 3 billion metric tons of carbon dioxide in 2020, one of the lowest amounts in recent history. Taking internal combustion engine cars off the road will lower global temperatures and drastically improve air quality.
Reduced Range Anxiety
Some people balk at the roughly 250-mile range the average EV offers on a single charge. Coupled with a lack of electric and hydrogen charging infrastructure in many areas, buying an eco-friendly car can feel risky, especially for people living in rural regions or who want to vacation somewhere new. Finding a gas station in the Nevada desert can be hard enough, and locating a place to quickly charge an EV or hydrogen vehicle takes serious planning.
However, cars with an extended-range battery ease some of that anxiety. Drivers can fill the tank with gas or hydrogen as a backup in case the electric battery putters out.
Lower Fuel Costs
Although extended-range EVs can still use gas or hydrogen, drivers don’t have to rely on it as heavily. In fact, they can forgo it entirely if they like, choosing to operate on electric power alone. That translates to a lower fuel bill.
Another upside to EREVs is that drivers can charge them overnight in the garage. If homeowners connect their car charger to a solar panel, they can drive an extended-range battery EV without using fossil fuels.
A Long-Range Battery Inspires Driver Confidence
Range anxiety is one of the biggest barriers to widespread electric vehicle adoption. Car manufacturers have been exploring different ways to alleviate this fear, from fully electric vehicles with longer ranges to extended-range EVs with small auxiliary power units.
Until a reliable, accessible charging infrastructure becomes common, many consumers take comfort in EREVs due to their backup power source that fuels a long-range battery. These fuel-efficient cars may not be as green as fully electric vehicles, but they’re an excellent stopgap measure while the world waits for EVs to take off.