11th April 2019

Internal combustion engine developments of cheer for fleets and others not suited to plug-in adoption

Despite encouragement to switch to plug-in hybrid or fully-electric cars coming from all angles these days, it still remains an unfeasible move for various company car fleets and private motorists, for reasons ranging from annual mileages covered and vehicle affordability to the practicality limitations of charging.

Fortunately, certain OEMS are continuing to devote considerable resources to petrol and diesel internal combustion engines, identifying that they still have an important place in today’s transitioning automotive world and society in general.

With all the anti-diesel sentiment, WLTP’s introduction and a lack of company car tax clarity beyond 2021, the current landscape is particularly confusing for fleet managers but also leaves private motorists struggling to decide whether to return to petrol, especially in light of UK vehicular CO2 emissions rising again1 amidst the focus on driving down nitrogen oxide and particulate matter.

Harnessing the advantages of petrol and diesel in one engine

Mazda uniquely aims to blend together the distinct benefits of ‘spark ignition’ petrol and ‘compression ignition’ diesel engines with its new SKYACTIV-X unit after asserting boldly that the average ‘well-to-wheel’ CO2 emissions of an electric vehicle can closely resemble those of a conventional car depending on the fossil fuel mix and production processes involved, and that society’s wish for a drastic reduction in greenhouse gas emissions won’t foreseeably be satisfied by EVs2.

The highly lean mixture of fuel and air necessary for optimal fuel economy can’t be fired by typical spark plugs, but stable and predictable combustion has long been deemed unattainable by OEMs due to the narrow parameters involved. Mazda’s proprietary ‘Spark Controlled Compression Ignition (SPCCI)’ technology, as incorporated into SKYACTIV-X alongside a supercharger, is anticipated as delivering up to 30% more torque while at the same time offering up to 30% more efficiency in comparison to the Japanese car-maker’s SKYACTIV-G engines and even its diesel units.

This exciting new powertrain will be introduced in H2 2019 via the stunning new Mazda3, to Europe first3, where strict emissions targets have a greater focus than in other parts of the world, and Mazda intends to tune the engine differently for each of its international markets. It’s expected that the SKYACTIV-X variant will have a 2-litre displacement and will likely be mated to the marque’s ‘mild’ M-Hybrid technology. Although Mazda’s hatchback has primarily appealed to private motorists rather than fleets over the years, the new model’s impressively clever technology is certainly worthy of consideration by organisations looking to adopt the best all-round conventionally-fuelled engines available.

Super-efficient diesel models are abundant and OEMs still believe in the fuel

Although WLTP has come along and squashed real-world fuel economy figures down to much more realistic levels, which is one of the Europe-wide programme’s chief aims, a plethora of models popular for families and fleets alike still offer headline capabilities of 70-80mpg, which various entities’ real-world tests identify as averaging in the mid-50s. Notable examples include the Honda Civic 1.6 i-DTEC, new Ford Focus 1.5 EcoBlue, Vauxhall Astra 1.6 CDTi, certain diesel variants of the BMW 1 Series which perennially performs strongly in business contract hire and leasing charts, Peugeot and Citroen models powered by the 1.6 BlueHDi powerplant, and many SEAT, SKODA, Volkswagen and other VAG iterations with the 1.6 TDI diesel engine at the heart.

In Q4 2018, Klaus Froelich from BMW’s board explained frankly that electric vehicles’ production costs and hence list prices will never reach the relatively affordable levels that internal combustion engine models continue to be marketed at. Speaking to Australia’s GoAuto4, he described BMW’s diesel engine development strides as ‘quite dramatic’, asserting that the brand has ‘more or less the best diesels’ and ‘the lowest emissions’ in his view. While he conceded that high-performance diesel monikers will likely reduce or perhaps disappear due to ever-stricter emissions targets, and that BMW and other brands’ diesel line-ups will almost certainly continue to be simplified, Mr Froelich still believes that ‘a modern diesel is a very good solution’. Perhaps surprisingly, he labelled the narrative around electro-mobility as ‘a little bit irrational’ and expects that, even as far on as 2030, BMW’s model range will still feature internal combustion engines in 85% of instances.

Cars that avoid the 4% diesel tax supplement

At a time when businesses and therefore their fleets face uncertainty due to factors from Brexit and WLTP to the inability to plan renewal cycles without tax bands beyond 2021 having been confirmed, savings and efficiencies are considerably important. Although the diesel supplement’s current increased level of 4% in respect of benefit-in-kind (BIK) tax on company cars doesn’t elevate costs substantially in real terms, avoiding having to pay it would certainly be welcomed by most decision-makers.

In order to limbo under this additional tax that is aimed at NOx emissions, a diesel car needs to comply with the Real Driving Emissions Step 2 (RDE2) test and meet not just Euro 6d-TEMP standards5, which many models do now reflect, but Euro 6d-full levels that won’t be mandatory until January 2020. Euro 6d-TEMP conformity allows a car to emit up to 2.1 times the prescribed forthcoming standard of 80mg/km NOx, while full Euro 6d compliance means that a diesel model has been configured to emit no more than 1.5 times that level i.e. 120mg/km NOx. Some OEMS such as Peugeot actively label their models as ‘Euro 6.2’, which corresponds to the temporary standard, and the French car-maker has revealed to us that it will soon be introducing Euro 6.3 engines meeting RDE2 standards, likely during the spring.

For now, two OEMs produce specific cars that are fully RDE2 compliant and avoid the diesel supplement surcharge on BIK. Firstly, Mercedes-Benz’s new A-Class and B-Class in ‘200d’ and ‘220d’ guises do not incur the 4% tax uplift, while fuel economy following WLTP testing has been identified as up to 67.3mpg combined, which is impressive. When purchased or leased with these engines6, the new A-Class attracts BIK of 23% compared to the A 180 d, for example, which has a rate of 26%.

The other OEM offering a fully RDE2-compliant solution is Jaguar7 and the model in question is again a company car favourite – the British marque’s XF saloon. Side-stepping the 4% diesel BIK supplement isn’t just restricted to the lower-powered variant, as both 163bhp and 180bhp rear-wheel drive versions of the XF have been optimised in order to meet RDE2 standards, with up to an 8% CO2 reduction. Along with other efficiency-boosting measures such as fitting ultra-low resistance tyres, Jaguar estimates that as much as £2,304 could be saved by a company car driver choosing the new XF over a three-year term, partly because the model’s first year road tax or VED figure also presents a saving.

While considerable emphasis continues to be placed on adopting plug-in and electric vehicles, it’s clear that certain OEMs and particularly those with a strong presence in the company car fleet space are still investing in making their diesel and even petrol models as efficient as possible, which is encouraging for organisations and also private motorists not yet ready to make the switch.


1. https://uk.motor1.com/news/299978/co2-emissions-rocket-ditch-diesel/
2. https://www.insidemazda.co.uk/2018/03/13/mazdas-new-skyactiv-x-engine-has-potential-to-rival-c02-of-evs-when-measured-well-to-wheel/
3. https://www.motortrend.com/news/mazda-skyactiv-x-engine-emissions/
4. https://www.goauto.com.au/news/bmw/paris-show-bmw-committed-to-diesel/2018-10-08/75892.html
5. https://www.nextgreencar.com/features/8359/car-tax-changes-cause-confusion-for-diesel-buyers/
6. https://www.fleetnews.co.uk/news/manufacturer-news/2018/11/13/new-mercedes-a-class-diesel-avoids-4-bik-surcharge
7. https://www.businesscar.co.uk/news/2019/wc-jan-28/jaguar-xf-gets-revised-diesel-engines-to-beat-company-car-tax-surcharge