PHEVs Have Proven a Worldwide Mobility Solution Instead of an Interim Technology

Worldwide, Plug-In Hybrid EV sales growth is exceeding that of BEVs. With myriad benefits and a receptive audience, this once-interim technology could well be the way forward.

Looking for a new set of wheels? Find it here with CARmag.

The year 2024 marked some significant developments for the EV industry. Growth continued with sales of plug-in vehicles increasing by 26% YoY (year on year) to a total of 17.2 million and an increased global market share of 22%. Of this volume, 63% comprised Battery Electric Vehicles (BEVs), with the balance of 37% being Plug-in Hybrid Electric Vehicles (PHEVs). This share grew from 31% in 2023, following YoY PHEV growth of 53% vs just 14% for BEVs.

This trend contradicts previous industry assumptions that view hybrids as merely an interim solution in the transition from internal combustion engines (ICE) to BEV adoption, suggesting that the current overall BEV offering is not appealing to motorists to the extent as much as originally forecast. Those switching from an ICE vehicle to a PHEV in preference to a BEV, will have their own reasons for doing so, but these will likely include concerns over vehicle pricing, charging infrastructure, range anxiety, and resale value.

The same BEV market growth forecast formed the basis of vehicle manufacturers’ planning regarding future products, manufacturing facilities and development expenditure. Many planned to phase out ICE vehicles by 2030, had moved development resources away from ICE powertrains and towards new BEV line-ups on dedicated platforms, while building new BEV-dedicated manufacturing facilities, or converting existing facilities. The past year has seen numerous announcements revising these plans in line with the change in customer demand. These include extended life cycles for some existing ICE models, the inclusion of PHEV derivatives in models originally intended to be BEV-only, and resumption of ICE development, including optimisation for use in PHEV drivetrains. In addition, the launches of some planned BEV models, as well as the dedicated facilities for their production, have been delayed.

As indicated by their naming, all hybrid vehicles feature both an ICE and electric motor(s). The way these complement one other determines their categorisation as mild hybrid (MHEV), hybrid (HEV) or PHEV. Each of these categories provides a different solution in terms of performance, fuel consumption, driving range and cost. PHEV

The entry point to vehicle electrification is the MHEV, an ICE vehicle fitted with a Belt Driven Starter Generator (BSG) or an Integrated Starter Generator (ISG), powered by a compact 48 V battery. In addition to acting as a powerful starter, it provides an additional 10-15 kW to the ICE under high load conditions. Charged primarily by regenerative braking, the battery can also be utilised to drive ancillaries such as power steering, to further reduce engine load. The system has become popular with European manufacturers seeking a cost-effective means of reducing vehicle emissions, while Toyota recently introduced it on some Hilux derivatives, providing benefits in performance, along with reductions in fuel consumption and emissions.

The next step up in electrification is the HEV, in which the ICE and electric motor(s), are usually combined in a series-parallel hybrid configuration. Here the ICE drives a generator which powers an electric motor. This, in turn, drives the wheels (series) but is capable of driving the wheels directly in certain driving conditions (parallel). The driving experience is like a conventional ICE vehicle, the power management controller engaging the electric motor to assist during acceleration when ICE consumption is at its worst, but allowing ICE-only operation at steady speeds when it is at its most efficient. The small battery is both cost-effective and has adequate capacity in this application, as it is quickly and frequently recharged by the ICE and regenerative braking. Originally popularised by the Toyota Prius and certain Honda models, the Toyota Corolla Cross Hybrid models are primarily responsible for the significant growth of HEVs in the SA market, providing cost effective fuel consumption and emission reduction benefits.

In addition to charging via regenerative braking or the ICE driving a generator, PHEVs can be plugged in to the mains supply network and their traction batteries charged via an onboard charger. However, their recent popularity has seen the emergence of different PHEVs types, each with their own characteristics and benefits.

The most common are PHEV derivatives included in predominantly ICE model ranges. Battery capacities are smaller than equivalent BEVs, usually in the 10-20 kWh range, and typically provide EV-mode ranges of 45 – 90 km, adequate for most daily commutes. Coupled with overnight charging, this battery capacity is sufficient to permit EV mode commuting in urban areas where tailpipe emissions have the most impact on human health, while overall driving range is better than their ICE equivalents. Most current PHEVs offer AC charging, either via a normal electric socket or via a home or public fast charger. Owing to the small battery size, this will prove adequate for most owners, however, those motorists requiring frequent public fast charging might prefer a model capable of DC fast charging. An interesting new development, mainly in China, has been the emergence of longer-range PHEVs with larger batteries. These can extend the EV-only range to around 200 km, reducing the necessity for frequent charging. Overall driving ranges are also increased to 1 000 km or more.

Incorporating the electric motor also provides a significant performance boost, but where this is not required, the ICE is downsized for further improved fuel efficiency. Typically, the electric motor is fitted between the ICE and transmission, coupled via an automated clutch, allowing series-parallel hybrid operation. However, the electric motor is sometimes mounted on the undriven axle, providing AWD capability as an added benefit. Technically, these PHEV drivetrains are relatively straightforward, and the challenge is ensuring smooth driveability through seamless transition between the two power sources at all speeds, throttle openings, and load conditions.

In an interesting development, BYD has become the tenth manufacturer to enter the SA PHEV market with the launch of its Shark 4×4 Double Cab. It features a 1.5T ICE primarily used to charge the 29.6 kWh battery powering front and rear electric motors, but also capable of driving the front wheels directly at higher speeds. Expected combined outputs of 320 kW and 650 N.m will make it SA’s most powerful bakkie, with an impressive range of 840 km.

In addition to these mainstream PHEVs, the technology is increasingly being used in supercars, covered in detail in the December 2024 issue. The focus in these applications is purely on maintaining performance when using a smaller ICE, the motor providing additional power and torque. In some cases, additional electric motor(s) are incorporated on the front axle, providing 4WD and torque vectoring to improve traction and handling. A reduction in emissions and the ability to cover short distances in EV mode are added benefits. PHEVs

A recent trend has been renewed interest in Extended Range Electric Vehicles (EREV), as initially seen in BMW’s i3 REx model which used a 650 cc motorcycle engine to power a generator, charge the battery, and extend vehicle range. While technically series hybrid PHEVs, they differ from ICE-derived PHEVs in that they are derived from BEVs, with an ICE only working to charge the battery and not drive the wheels directly. Initial interest is coming from US full-size pick-up and SUV manufacturers, where BEVs, despite 130 kWh batteries weighing 800 kg or more, do not provide sufficient range, particularly when towing. RAM has already announced the 1500 Ramcharger, which utilises a relatively small 92 kWh battery to power its front and rear 250 kW electric motors. EV-only range is 225 km but with additional charging provided by the familiar Pentastar 3.6-litre V6 this increases to 1 100 km. Hyundai also recently confirmed an EREV version of its Ioniq 9 BEV; a large SUV due in select markets next year, describing the technology as a bridge between ICE and EV.

Other than being built on EV platforms, where production volumes are possibly falling short of original forecasts, costs are contained by fitting a smaller battery to offset the cost of the ICE generator. As it doesn’t drive the vehicle directly, the ICE can also be managed to run at its most efficient engine speed, or linked to vehicle speed, making it sound and feel “normal” to the driver.
The upturn in worldwide PHEV sales combined with the increase in models offered, and new developments such as long-range PHEVs and EREVs, confirm their growing appeal to consumers. Pricing is slightly lower than BEVs, smaller batteries offsetting the additional ICE cost, but the real benefit is useable EV driving without range anxiety. With BEV prices slowly falling and ranges expanding, their appeal may be relatively short-lived in markets where BEVs are already well established. However, in markets with large travelling distances and less-developed charging infrastructure, PHEVs could provide an extended transition from ICE vehicles to BEVs.

Find the full feature in the May 2025 issue of CAR Magazine.

Browse thousands of new and used cars here with CARmag.

The post PHEVs Have Proven a Worldwide Mobility Solution Instead of an Interim Technology appeared first on CAR Magazine.

The Car Guide