Diesel cars have been put under the microscope recently due to environmental effects, would you buy one today?
Diesel cars have come under close scrutiny in the last few months across the globe and a number of major cities such as Paris, Madrid, Athens and Mexico City have stated that by the year 2025 all diesel vehicles will not be allowed to enter their respective city centres.
Diesel usage has long been under extensive review due to the harmful impact diesel pollution has on air quality.
London’s Mayor, Sadiq Khan, in response to the intense focus on air pollution has revealed his plans to introduce the Ultra Low Emission Zone in central London by April 2019.
The “toxin tax”, as it has become to be known, will see cars that emit high levels of unhealthy pollution pay a fee to enter the city of London, and the expected result should be an improvement in air quality for central London dwellers and users alike.
The Prime Minister, Theresa May, has acknowledged that government has in the past championed diesel engines resulting in a high number of diesel cars on our roads, she has suggested that drivers with older vehicles could be incentivised to trade in.
However, recent figures published by the Society of Motor Manufacturers and Traders (SMMT) indicate that diesel popularity is on the increase! March saw some 244,263 diesel cars sold nationwide – the highest month ever and a rise of 1.6% over the same period last year.
Based on that data, it appears that diesel cars still remain hugely popular.
Diesel vs. Petrol?
There are a number of different technical characteristics between diesel and petrol engines. For the consumer, diesel has a higher efficiency level over petrol so you can get more from your fuel especially on longer journeys. The flip side to this higher efficiency is that diesel engines tend to require a little more maintenance than petrol engines.
Petrol engines, alternatively, tend to be cheaper on fuel costs and don’t require as much maintenance as diesel engines. Petrol engines, however, are less fuel efficient and don’t offer the refined power of a diesel engine. Petrol engines tend to have a lower flat torque which means the vehicle is likely to require more frequent gear changing.
Diesel engines have demonstrated unfortunately not to be as environmentally friendly when compared to petrol engines, and while diesel engines produce less CO2, they can also generate up to four times as much nitrogen dioxide pollution and a further staggering 22 times more “particulates” – these are small microscopic particles that are harmful to humans.
However, advances in low sulphur diesel fuel and eco-friendly improvements to diesel engine technology means modern and future diesel engines may be significantly better than their predecessors. Also, Ultra-Low Sulphur Diesel (ULSD) has been developed to reduce diesel emissions and in some cases is 97% cleaner than standard diesel fuel.
So why do diesel cars cost more?
A review of car prices will quickly illustrate a premium price correlation when choosing diesel cars compared to petrol cars, and there’s a number of reasons for this;
- Diesel cars have higher compression rates in comparison to petrol cars – this means that generally, diesel cars are more powerful, more efficient and provide higher torque.
- The technology behind a diesel car is more expensive in order to produce this extra power and efficiency.
- There are more materials and resources required to build a diesel engine in comparison to a petrol engine, again adding to the cost.
Are there benefits of a diesel car?
The key benefits of purchasing a diesel car and paying the extra premium can include:
- Diesel cars are better choices for drivers who make longer journeys more regularly. Diesel cars have better fuel efficiency, so although diesel fuel costs slightly more, a diesel car can achieve a higher MPG (miles per gallon) compared to its petrol equivalent.
- Diesel cars provide more power and tend to be equipped with a turbocharger to allow for faster acceleration.
- Diesel cars provide more power but a lower RPM (revolutions per minute), this means the car doesn’t need to be revved higher to accelerate which provides a more comfortable and smooth journey.
- Due to diesel’s superior power, diesel cars have a better towing ability in comparison to their petrol counterparts. This is the reason that most heavy-duty lorries/vehicles use diesel engines rather than petrol.
- Data suggests that diesel cars held 63% of their value after 3 years in comparison to petrol cars (53%), and hybrids (55%) making diesel cars a more attractive financial investment.
What are the downsides of a diesel car?
There are also a number of negative considerations to account for when you invest in a diesel car including:
- Though diesel fuel is now only marginally more expensive than petrol, there is a higher demand for diesel fuel in trade and industry keeping demand high and therefore costs high too!
- Cleaner diesel fuels have advanced and no longer require excess water to be “bled” out of the system. However, some diesel vehicles do still require their separators to be emptied. This is just one example demonstrating why diesel vehicles are higher maintenance.
- When something goes wrong in a diesel car it often costs more to repair the fault than a petrol car, as the technology and parts are generally more expensive.
- Diesel cars are unfortunately not as environmentally friendly when compared to petrol cars.
Are diesel cars a better purchase?
There’s a number of different reasons why diesel cars may be seen as a better purchase.
Firstly, the choice to purchase a diesel car over petrol car can be as simple as offering a smoother and more comfortable drive. Diesel drivers tend to be travelling long distances and as such, comfort is an important factor. Diesel car drivers tend to appreciate the comparably more calming driving experience.
Secondly, although the initial cost of purchasing a diesel car may be higher, diesel cars hold their value and tend to depreciate more slowly. And as above, diesel cars can retain up to 10% more residual value than a petrol car after 3 years.
Thirdly, as a consequence of fuel efficiency, a diesel car could actually save you substantially more on fuel over the lifetime of the car. If you use your diesel car to drive long distances regularly, and with a much higher MPG for motorway driving and long journeys, depending on your travel needs, the cost saving could outweigh the additional amount you initially paid for a diesel engine!
Purchasing a car can be a major investment and financially speaking the decision to choose a diesel car should be primarily based on whether you expect to be driving long distances regularly and consequently, and so need a car that will be fuel efficient.
Any decision will be aided by collating as much information as possible, and so, a consideration of the current dialogue from environmental and political bodies regarding diesel cars, and new initiatives like diesel specific legislation and potential government scrappage schemes should be taken into account.
Ultimately, car buyers need to weigh up the importance of fuel economy and comfort versus environmental factors and uncertainty about the future of diesel.