Are Diesel Engines Better Than Petrol? Quick Answer

This article will explain Are Diesel Engines Better Than Petrol? Although gasoline and diesel engines are still popular despite the popularity of electric and hybrid vehicles, we list the benefits and drawbacks of these conventional fuels.

Around 45% of all new car sales are conventional gasoline vehicles, and even while diesel vehicles are no longer as popular as they once were, thousands of diesel vehicles still find new owners yearly.

Thus, it is evident that these cars still meet the needs of millions of drivers despite the impending prohibition on the sale of new gasoline and diesel vehicles.

If you fall into this category and are debating between gasoline and diesel power, our study will assist you in knowing whether diesel engines are better than petrol Or not.

Are Diesel Engines Better Than Petrol?

Even though they are less efficient for people who drive mostly in cities, diesel engines are still more effective than gas engines.

Also, diesel cars have more torque, leading to better fuel efficiency and more powerful acceleration.

What’s The Difference Between Petrol And Diesel Cars?

Between gasoline and diesel cars, several important distinctions must be made in terms of ownership, driving, and legal requirements.

Purchase Price 

A diesel car will nearly always cost more than a comparable petrol car, albeit only sometimes by a significant amount.

For instance, the suggested manufacturer price for a petrol BMW 520i in M Sport specification as of August 2022 is $ 55,795, whereas the price for a diesel 520d M Sport is $ 57,159.

There are several reasons behind these higher purchase prices. One of these is that diesel engines must be more powerful because diesel ignites gasoline by compressing it to extremely high pressure rather than utilizing a spark plug.

Emission-control devices like diesel particle filters and AdBlue also increase costs.

Running Costs

We’ll look at the many aspects that determine a vehicle’s running costs one at a time.

Insurance

The situation is comparable in this area. Due to potentially greater repair expenses, a diesel car may have slightly higher insurance than an equal petrol vehicle, but the difference isn’t that significant.

Service

Once more, diesel vehicles typically have more systems (such as the ones for pollution control noted above) than petrol vehicles, which can raise the service cost, albeit only sometimes much.

It’s important to note that older diesel cars have lower MoT pass rates than gasoline vehicles, which could result in future costs.

AdBlue

To lessen dangerous nitrogen dioxide (NOx) emissions, modern diesel vehicles employ Selective Catalytic Reduction, specifically a liquid commonly referred to as AdBlue.

AdBlue systems use microscopic injections of an ammonia-based liquid into exhaust gases to reduce NOx emissions, and AdBlue tanks need to be refilled occasionally.

An AdBlue tank might hold 10 liters, and if purchased online, AdBlue would cost about £20 for such volume.

AdBlue use varies depending on the vehicle and the driver, but it is realistic to anticipate that 10 liters of AdBlue will last between 3,000 and 6,000 miles, making the expense very insignificant.

Fuel Prices

This is an area where diesel automobiles excel. The diesel BMW 520d achieves 57.6 mpg compared to the previously mentioned petrol BMW 520i’s official 44.8 mpg.

This 28% advantage means that for high-mileage drivers, a diesel car will soon offset any increased purchase and operating costs it may have over its petrol counterpart.

A 60-liter tank will cost a driver of gasoline $ 126 and a driver of diesel $135.46 to fill up, for example, if a liter of gasoline costs $2.11 and a liter of diesel costs $2.26.

However, the 520i driver will travel 582 miles on a tank, compared to the 520d driver’s 749 miles.

The petrol driver will pay 17.5 cents per mile, while the diesel driver will pay 14.6 cents per mile, saving 2.9 cents per mile.

For example, if a diesel car driver drives 20,000 miles annually for three years, they will have saved $2,158.37 on taxes and emissions.

Emissions And Tax

Older diesel engines produce a lot of pollution. Still, modern diesel can be compared to their petrol-powered brothers in terms of cleanliness thanks to AdBlue and diesel particulate filters (DPFs), which catch soot from exhaust fumes.

Diesel vehicles produce far less carbon dioxide (CO2) than identical petrol vehicles, which is one of the reasons why road and company vehicle taxes previously supported them.

According to the current road tax system, a car’s first-year rate is based on how much CO2 it produces. Therefore, a 520d will cost $235, while a 520i will cost $285.04.

With the diesel 520d attracting a 30% Benefit-in-Kind rate and the petrol 520i receiving a 33% rate (exact CO2 emissions and, therefore, tax costs will be affected by alloy wheel sizes and other factors, so do check figures yourself before any potential purchase), company car tax is still determined by CO2 emissions.

It’s also important to note that diesel automobiles face significantly stricter restrictions in emission zones like London’s ULEZ (schemes are also beginning to arise in other cities).

While diesel normally needs to comply with Euro 6 emission rules, most of these programs let petrol automobiles satisfy relatively dated Euro 4 emission regulations access zones without paying.

This means that a petrol car from 2006 will likely avoid such costs, while diesel would need to be significantly more recent – from about 2015 on – to avoid penalties.

Driving And Performance

The driving characteristics of gasoline and diesel vehicles differ, albeit not significantly. Each will be handled in turn.

Noise: Even though diesel automobiles have significantly improved over the years (sports cars excluded), they are noisier than an equal petrol car.

The sound emitted by a diesel car is frequently referred to as a “clatter,” it is typically less pleasant to the ear than the sound made by a petrol engine.

Engine speed/revs: Diesel cars normally have a maximum rpm (revolutions per minute) of 5,000, as opposed to the 6,500 rpm that a petrol car may have. This means that diesel cars have a lower rev limit than petrol cars.

If you think of power as how hard you push a spanner and torque as how long the spanner is, diesel automobiles produce less power but more torque than a comparable petrol engine.

As a result, diesel engines are better adapted for pulling caravans and other similar objects, and they also accelerate more easily, especially at high speeds.

Diesel are ideal highway vehicles due to their low-rev nature and effortless torque, contributing to fuel efficiency.

Diesel particulate filters (DPFs): DPFs capture minute soot particles in a filter by absorbing them from diesel vehicles’ exhaust. The stored soot must be periodically burned off (regenerated).

This can only happen when an engine is at operational temperature, and the vehicle travels at a speed greater than a specific threshold. You risk letting a DPF become blocked if you don’t regenerate it when necessary.

This indicates that a petrol, hybrid, or electric car may be preferable to a diesel for persons who mostly drive in towns and rarely exceed 50mph.

What Are The Pros Of Petrol?

Lower Price

Diesel is more expensive than gasoline at the pump. Fill up your tank, and you’ll spend about 2p less for gasoline than for diesel per liter. Even if it’s only a £1 save on a 50-litre fill, you’ll see the difference after a year.

Better For Short Trips

A petrol car can be a fantastic choice if you’re looking for an inexpensive, no-frills vehicle to transport your children to school, make your weekly grocery run, or handle frequent short excursions inside the city. Modern turbocharged tiny petrol engines have the potential to be quick and fuel-efficient.

Less Local Air Pollution

Diesel engines operate differently than gasoline engines, and one of the results is that particle emissions from gasoline engines are typically far lower.

Compared to the CO2 emissions associated with climate change, these are different: Particulate emissions contribute to local air pollution, especially in metropolitan areas, which has been related to respiratory and other health issues.

Petrol Cars Are Usually Quieter

Petrol-powered vehicles continue to be generally smoother and quieter than diesel vehicles despite developments in diesel engine technology.

Again, this is because they operate slightly differently; thus, a petrol car has less noise and vibration inside, especially when it has just been started from scratch.

What Are The Cons Of Petrol?

Petrol Cars Are Generally Less Fuel-Efficient Than Diesel

Petrol may cost less per liter than diesel, but you may use more. Diesel engines are most effective when traveling longer distances at higher average speeds.

If your only lengthy car trip is the yearly 200-mile round trip to visit family, it won’t matter, but if long road trips are a regular part of your life, you’ll spend much more on fuel with a petrol car.

Higher CO2 Emissions

One of the principal greenhouse gases linked to climate change is carbon dioxide (CO2), and petrol cars emit more CO2 from their exhaust pipes than an equivalent diesel.

Because of the higher CO2 output, gasoline vehicles registered before April 2017 will likely have higher tax rates.

Before that time, the government calculated a car’s annual road fund license (more formally known as “road tax”) using CO2 emissions.

As a result, vehicles with lower CO2 outputs—typically diesel and hybrid vehicles—pay less tax.

What Are The Pros Of Diesel?

Better For Longer Journeys And Towing

Diesel engines can provide higher power at lower engine rpm than their petrol equivalents. Because diesel engines don’t have to work as hard to provide the same performance as petrol engines, they feel more suited for lengthy highway trips. Additionally, this makes diesel vehicles more suitable for hauling.

Better Fuel Economy

Diesel automobiles offer greater mileage than gasoline ones, like for like. The energy content of diesel fuel is higher than that of gasoline for the same volume.

There may be a significant difference: An official average mpg for a diesel engine is typically around 70 mpg, compared to an equal petrol model’s average of roughly 50 mpg.

Lower CO2 Emissions

Diesel cars emit less CO2 than identical petrol cars since CO2 emissions are directly correlated to an engine’s fuel consumption.

What Are The Cons Of Diesel?

Diesels Are More Costly To Buy

Due in part to the complex equipment that current diesel automobiles are equipped with to decrease their particle emissions, diesel cars are more expensive than their petrol-powered counterparts.

Can Cause Poor Air Quality

Older diesel engines’ nitrogen oxide (NOx) emissions have been connected to poor air quality, breathing issues, and other health issues in populated regions.

Diesels Don’t Like Short Trips

Most contemporary diesel vehicles have a diesel particulate filter (DPF) in their exhaust that lowers dangerous particle emissions.

If you frequently make short, low-speed trips, the DPF may become blocked, leading to associated engine issues that can be expensive to repair.

The DPF needs the engine to reach a particular temperature to function effectively.

Conclusion

Diesel engines are better than petrol. The answer will depend on your mileage and the kind of miles you go. Drivers who cover most of their miles in brief, frequent journeys inside communities shouldn’t use diesel. A diesel vehicle may be better if you frequently travel longer distances or on highways.

Long-term, the government intends to halt the sale of new gasoline and diesel vehicles starting in 2030 to entice consumers to purchase hybrid and electric vehicles with fewer emissions.

For now, older gasoline and diesel cars offer various models and superior efficiency, so depending on your demands, either could be a wise decision.

Frequently Asked Questions