Car industry renaissance — powertrains reinvented
The car industry is being reshaped in ways which we have not seen in the last hundred years since Ford Model T’s assembly lines made cars affordable.
Setting the stage
I am genuinely excited about the car industry’s reaction to the environmental pressure and the rise of EVs. Constraints and pressure always stimulate creativity and challenges in front of traditional car manufacturers, being existential, stimulate a lot of creativity. The ingenuity and variety of approaches to face the challenges makes the car industry exciting to watch these days.
It reminds me of the era of handheld computers and pocket digital assistants (PDAs) of the late 90's. Back then each manufacturer had its own unique approach to both hardware and software and switching between devices was like flying between galaxies. There were ingenious devices like Apple MessagePad with its Newton operating system. HP Palmtop, HP OmniGo and Palm Pilot with Graffiti handwriting recognition, Compaq iPAQ and finally the mind-blowing Psion Series 3 and Series 5. I used to be following and reviewing these devices for Mobil.cz (later acquired by MaFra) and you can still find remains of my creations in its archive (sorry Czech only).
I stopped working for the PDA section of Mobil.cz after reviewing the fourth or fifth PDA with Windows CE operating system, because I became bored. Windows CE devices were essentially identical, built to the same Microsoft’s blueprint and had only few minor differences in between them. Nothing to discover and explore anymore, time to move on.
The same trend happened in the car industry over the twentieth century. Most of the car manufacturers stopped experimenting and consolidated their powertrains on all-in-front front-wheel drive (FWD) architecture. Except for a few holdouts, concentrated in the luxury car segment, who kept maintaining their rear-wheel-drive (RWD) powertrains, and few outliers such as Subaru, with its AWD system, the cars from different manufactures became very much alike.
In the most typical car powertrain, you get a transversely mounted engine powering the front axle. This means that the front wheels are used both for steering and powering the vehicle.
The beginning of the new era
It is hard to believe that the dawn of the new era came already a quarter of century ago. Toyota Prius and its unique Hybrid Synergy Drive (HSD) combining internal combustion engine with rechargeable battery pack, pair of electric motors / generators and uniquely integrated planetary gearbox into what Toyota calls e-CVT. A decade after Prius came Tesla Roadster which ushered us into the pure electric vehicle (EV) era. Yet it took almost another decade and one major emissions cheating scandal until things finally got into full motion.
In transition to cleaner transport
We are still early in the transition to cleaner transport. It is indisputable that greener ways to move people and goods around could bring many benefits. Yet the jury is still out, whether the future will belong to the EVs as we know today, whether fuel cell-powered cars will take over, whether the future cars will burn hydrogen directly in a modified internal combustion engine, or whether we settle on some new yet-to-be-discovered technology.
Given the level of uncertainty, different car manufacturers are taking distinct bets on how the car of the future will look like, offering a large variety of EV-only and transitional hybrid powertrains in their recent vehicles.
FWD, RWD, or AWD?
If you ask me about my preferences regarding car powertrains, the stack-ranked list looks like this:
- AWD (active safety and fun to drive)
- RWD (fun to drive)
- FWD (I am good with moving from A to B.)
Permanent all-wheel drive (AWD) is my preferred choice. It is good that the size and weight of electric motors makes dual motor configurations viable even in mainstream cars. Most of the EV manufacturers are offering AWD with two separate electric motors (dual motor) as an option or making them part of higher-level trims.
The more important question is which kind of powertrain servers as a foundation for the AWD option and thus becomes installed in majority of cars shipped. Some manufacturers such as Hyundai/Kia with its E-GMP platform and Volkswagen with its MEB platform are betting on rear-wheel drive (RWD) powertrains. I find this development quite exciting because it can lead to renaissance of rear-wheel drive models which are more fun to drive than FWD cars which generally suffer from understeering driving characteristics.
It is important to note that Hyundai/Kia are hedging their bets and some of their smaller EV models such as Hyundai Kona and Kia Niro are using FWD powertrain. Many other manufacturers including Toyota, Nissan and most of the European brands are also using FWD powertrains even for EV variants of their cars. The traditional FWD setup allows them to reuse vehicle platforms between EV, hybrid, and ICE powertrains, rather than using dedicated EV-only platforms.
I personally consider FWD EVs suboptimal because the electric engines offer instant torque which is difficult to transfer to the road through front wheels during acceleration and the slippage needs to be controlled electronically, thus restricting the power output.
Hybrids and other beasts
Even more interesting things happen in the world of hybrid powertrains. While most of the hybrid car manufacturers initially took inspiration from Toyota, the leader of the hybrid cars segment. Recently we can see quite interesting designs being produced. Mitsubishi in its Outlander and Eclipse Cross plug-in hybrid (PHEV) models gets away with the gearbox and uses a pair of electric motors in dual motor configuration to power the wheels most of the time. Only at cruising speeds, the ICE engine connects to the front wheels using a clutch with fixed gear ratio.
Honda is applying a remarkably similar approach in its e:HEV powertrain implemented in Honda Civic and the new Honda CR-V. The distinction from Mitsubishi is that Honda uses smaller battery pack, and their current e:HEV models are not plug-in hybrids, even though a plug-in e:HEV CR-V might be coming later.
Nissan goes one step further than its Japanese rivals and not only does away with the gearbox in its e-POWER technology, but its 3-cylinder turbo-charged petrol engine never powers the wheels directly. The ICE engine is exclusively used to generate electricity for the electric motors and recharge the battery. Nissan currently applies e-POWER to Qashqai model, powering the front wheels, and to X-Trail offering dual motor AWD configuration in X-Trail e-POWER e-4ORCE model.
On the other side of the hybrid spectrum, we get cars, which are mostly EVs, but paired with a combustion engine range extender. The pioneer in this category is now discontinued BMW i3 REX (REX standing for Range EXtender). Mazda just recently launched Mazda MX-30 R-EV plug-in hybrid based on the original MX-30 EV platform but this time with a smaller battery pack paired with the legendary Wankel rotary engine.
Wrapping up
As you can see in this brief overview, the car industry is currently booming with ideas and diverse approaches. We can see a strong push towards EVs on one side of the spectrum, but we can also see many bespoke attempts to innovate for the transitionary period by combining EV technology with internal combustion engines. The electric engine adoption enables dual motor configurations, thus democratizing AWD without major adverse impacts on fuel economy. The future of transport is yet to be settled and we can expect a decade of turbulent development ahead of us.
Fasten your seatbelts and enjoy the ride!