this post was submitted on 09 Mar 2026
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hmmm
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A couple manufacturers were showing off EREV at the big manufacturer auto show, basically EV with a small gas engine to extend the range. Less motor than a hybrid, but enough to get some pretty ridiculous range out of a single combined charge/tank. Basically what this image is implying.
Seems like a decent idea for people that use their vehicle for longer distances.
I've been asking forever why we aren't seeing gasoline electric vehicles. It's literally been standard practice for diesel locomotives for basically as long as diesels have been dominant, you hook a gigantic diesel generator (prime mover)to a pair of gigantic electric motors (traction motors), and when you want to slow the consist without consuming your precious air for more intense braking, you can just turn the motors into generators and dump the energy into giant resistor banks on the roof (dynamic braking) or into an battery powered engine behind your diesel electric engine
You get the power of electric motors, the mechanical simplicity of electric transmission, and the range and rapid refueling of an internal combustion engine. The disconnect between the prime mover and the traction motors means each can be tuned to their respective efficiency curves (especially if a bank of batteries/capacitors is included as a buffer) so you get more efficient idling, more efficient acceleration adds the options of connecting slugs (units with no prime mover nor control cab) or b-units (units with no cab)
They're called hybrids. The reason they're not in series is because it's more efficient once the engine is at "cruise" speed to just let the engine spin the wheels directly instead of losing 15% going engine to electric then electric to electric motor.
So instead of a transmission, hybrids use a planetary differential. That way everything is always spinning at maximum efficiency.
I suppose I could see how that could math out, assuming the engine running at an appropriate RPM to transmit to the wheels isn't less fuel efficient than an engine running at an appropriate RPM to generate electricity.
The thing that turns it on its head for gasoline electric though is the IC engine can be almost anything and do almost anything if all it's doing is spinning an alternator with sufficient power buffer before the electric motors. The IC engine could run at a single constant RPM at all times if that's most efficient, or it could be a more car-like thing that adjusts it's RPMs based on load. Or maybe it runs at constant RPMs but the count of active cylinders changes depending on load. The types of engines that can be used suddenly becomes immense because of this too
I just find it hard to believe that the most efficient option for a hybrid is 2 drivetrains. That always struck me like it was more engineers specialized in ICE vehicles simply designing what they know rather than something more bold and imaginative
That's exactly what the car does in real time. My Toyota switches constantly between the ice engine transferring energy to the electric motors and the electric motors turning off when they are outside of their most efficient range.
It has an onscreen graphic to show you while you drive for the curious. It has another screen that gives you a driving score to encourage a driving style that maximizes efficiency like having the battery recharge more by braking longer and smoother.
Sounds like a GM Volt (not Bolt) or a BMW i3. Good thing both models were discontinued. Just in time for gas prices to go up again, right on schedule.
A quick look seems like the EREVs proposed to be available in the US are all trucks and large SUVs. Ford, Jeep, Hyundai, and Genesis among others. That sucks, why do they have to be big cars? Like to have a smaller sedan with great range.
Because "trucks" have less stringent regulations (both for efficiency and safety) so farmers can keep using their old beater pickups.
BMW did it long ago in the i3 with the range extender. Not the best attempt though. They made it tiny, but it still had a heavy battery (though obviously not a very big one, just heavy for a car of this size), so to get the weight down, they used carbon fiber, but it was supposed to be an economy car and now with carbon fiber it was expensive.
Idea itself is not bad though.
this is a great idea! love it. can we skip the small engine and just install a small fission reactor instead?
im affraid we cannot.
Was the gas engine like a trickle charge?
Basically! The gasoline engine could provide some of the needed energy while driving to reduce battery drain but not enough to keep up with the motors' energy consumption. It still needs to be plugged in to charge and can be driven in pure electric mode for short distances
It’s been a couple months but if I remember right the gas engine worked alongside the battery, it wasn’t possible to direct drive the car with the gas engine. Yes, it could charge the battery.
Every hybrid made today has the engine direct drive the wheels when it's most efficient to do so. Serial hybrids died because they weren't as efficient.