The War on Diesel: is it justified?

Cars, Diesel, Fleet Manager, Government


In recent years, the uptake of diesel vehicles has played an important part in helping the UK to reach lower C02 emission targets. From buying diesel, UK motorists have prevented 3.5 million tonnes of C02 from going into the atmosphere since 2002.

However, following increased Government pressure in tackling air pollution and reducing emissions, the environmental impact of diesel has come under fire. Whilst some of the criticism is warranted, there’s a degree of misinformation which has created confusion over the dangers of diesel.

DDiesel in decline

The growing concerns surrounding diesel has without a doubt had an impact.

In May 2017, there were 20% fewer diesel registrations than the same time in the previous year. This, along with a decrease in market share of 8.8%, gives an early indication that drivers are starting to migrate away from diesel engines.

Whilst on the other hand, petrol and alternative fuelled vehicles (AFV) have benefited, having seen their market share increase by 5.8% and 27.2% respectively. As diesels become less attractive, leasing companies are already seeing residual values fall and monthly rentals increase.


Diesel first took a hit back in September 2015 when allegations were made that Volkswagen had been using what was called a ‘defeat device’ which made 11 million of their cars appear far less polluting than they were.

This sparked worldwide concern as a result, and consumers began to question the transparency of the motor industry.

With people beginning to question how clean diesel engines really are, more pressure has been piled on by the Government.

Headline articles on dieselSadiq Khan, Mayor of London has made it no secret that he wants to reduce the numbers of diesels entering the capital city. He unveiled his plans for a World-first Ultra Low Emission Zone (ULEZ) in April 2019.

From 8 April 2019, the most polluting cars, vans, and motorbikes will have to pay an additional £12.50 on top of the existing £11.50 congestion charge to drive through central London, which City Hall hope the move will result in a 50% decrease in emissions by 2020. Only diesels that do not meet Euro 6 standards will be applicable to the charge, so anything over four years old in 2019 will be charged.

Diesel coverage intensified further as the Government suggested proposals to introduce a Diesel Scrappage Scheme as part of their clean air strategy. The plans will involve offering motorists cash to scrap or ‘retrofit’ older diesel vehicles that emit high levels of Nitrogen Dioxide (NOx). NOx has negative health implications and has been linked to causing short-term and long-term health effects.

Is this the full picture?

The negative press surrounding diesel has created doubts over its future and more consumers are now beginning to look at petrol or alternative fuelled vehicles. However, diesels still have many benefits.

In terms of emissions, diesel has played a big role in tackling climate change. Since 2002, it has saved over 3.5 million tonnes of CO2 from going into the atmosphere. Moreover, a diesel engine emits on average 20% lower CO2 emissions than a petrol equivalent.

Reduction in NOx DieselIn fact, the cleanest 5% of diesel which were tested by Emissions Analytics are as clean as the average petrol car. The problem really arises when you look at older diesels.

In addition, diesel engines on average are more fuel efficient than their petrol alternatives. On average, diesels use 20% less fuel, and they typically cover 60% more miles. This makes them more useful for those who cover a higher number of miles.

Also new developments are occurring daily. Only last week, engineers at tech and tyre company Continental, released news of an electrified after-treatment system that is capable of reducing NOx emissions by around 60% under real-world driving. Using an electrically heated catalytic converter that uses a 48V electrical system, the catalyst heats up much quicker, allowing for highly efficient NOx reductions.

Does diesel still have a role to play in the fleet market?

96% of the UK’s 4.8 million commercial vehicles are powered by diesel engines. Commercial vehicle mileage equates to 61 billion miles travelled every year.

Of course diesel is still going to have a role to play.

And for the company car driver, they are motivated by tax. When the company car taxation changed in 2002, diesel became the engine of choice for most fleet drivers as it offered the best savings when it came to tax. Also, as highlighted previously, a high-mileage driver would still be better suited to diesel, as petrol engines and AFV’s are no match for diesel on efficiency and range.

And until that changes, high mileage drivers are more likely to be drawn to diesels.

For fleet policy makers however, it isn’t as clear cut. The solution lies in the individual needs of your business and understanding the unique nuances of your fleet.

What next?

Of course, it’s important to look ahead and plan effectively for the future. But tomorrow’s plans can only be realised if you act today.

With definitive dates still unknown, it’s essential to ensure that your policy has the flexibility to adapt and change when you need it to. We are urging businesses to avoid approaching your fleet policy as a blanket, rigid structure and opt for a more fluid and adaptable framework.

In essence, there is no ‘one size fits all’ solution.

Like many things, it’s about finding the right balance. Understanding what the right balance of diesel, petrol and alternative fuels looks like for your fleet is the next step for many businesses.

Why not let us help you start that process? Sit down with one of our fleet experts to help you find the right path for your fleet. With a straightforward and honest approach, we can assess your current fleet mix, your plans and aspirations and see if we can help you understand what action to take today.

Book a free Fleet Consultation to discover the right balance for you, or for more information, contact the team on:

0115 946 6466

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