When buying a car, there are a lot of elements to consider. Some choices – 2-door or 4-door, black or white, leather or cloth – are easy to make and are informed almost entirely by your personal taste. But, some choices – like whether you want a car that is petrol or diesel powered – requires a bit more research. Why? Because your choice could have financial, environmental and experiential consequences.
The Cost of Petrol Cars Vs. Diesel Cars
The cost of a car isn’t calculated using the purchase price alone. You also must factor in the cost of fuel, tax, insurance and servicing. So, while the cost of a comfortable, 4-door car with a diesel engine will cost around £1,500 more upfront than the equivalent car with a petrol engine, it could cost less over time.
Historically, this upfront cost was offset for owners of diesel cars because of lower fuel costs and reduced tax rates. Now, only the former applies. Before April 2018, drivers with cars that produced less than 100g/km of CO2 emissions (for example a Volvo S60, Audi A4 Saloon, or Hyundai i30 Tourer) got a tax break. As of April 2018, though, drivers with diesel cars – even those that produce less than 100g/km of CO2 – are required to pay tax.
But, diesel cars are still – in general – more fuel efficient and therefore require less fuel. While the cost of fuel per litre is slightly higher for diesel, the fuel economy (which is higher both on the motorway and around town) supports lower running costs.
When you also figure in the extra cost of car insurance which, for diesel cars, tends to be 10-15% higher because repairs on diesel cars tend to be more expensive, one could make the argument that in general, petrol cars cost less. Of course, this is completely dependent on the make and model.
The takeaway: do your research! The purchase price is just part of the equation.
Do Diesel Engines Pollute More Than Petrol Engines?
A lot of the conversation around diesel cars has to do with their environmental impact and, in particular, their toxic emissions. But, if you look back several years, you’ll see that in reaction to the 1997 Kyoto Protocol to reduce greenhouse gas emission (especially CO2), diesel was actually promoted as the environmentally friendly option. This, again, comes down to the cars’ fuel economy.
While diesel fuel does contain more carbon than petrol, their CO2 emission tends to be lower because diesel engines are a lean-burn meaning they use less fuel and more air compared to petrol engines.
So, what’s changed? Nothing…in terms of CO2 emissions. Now, the public (and governments) are equally concerned about toxic emissions that are immediately harmful to humans.
Both petrol and diesel engines produce nitrogen oxides, but petrol cars have a built-in three-way catalytic converter that cleans up these toxins to emit significantly less than diesel cars. Diesel cars have something similar – a diesel particulate filter or DPF – but these require regular maintenance.
This explains why, in the UK, new MOT rules dictate that diesel cars with a DPF can’t have visible smoke coming from their exhaust and can’t show any evidence of tampering. Both result in an automatic fail.
Given the environmental impact, higher tax rates, and more strict MOT rules, some people are starting to wonder if diesel cars will one day be banned. While it’s impossible to answer this question, it is worth mentioning that the UK government is under significant pressure to ban both diesel and petrol cars by 2032 to ensure all cars on the road are zero emission by 2042.
Are Diesel or Petrol Cars More Powerful?
If you’re looking for a car with some serious ‘get-up-and-go’, you might prefer a diesel powered vehicle. Diesel produces huge amounts of torque (power), which explains why lorries, buses and other large vehicles are often diesel powered. Torque allows for better overtaking power and towing ability but that’s not to say that petrol cars won’t get you where you’re going.
So, Which is Better?
That’s up to you! Both come with a list of pros and cons and it’s important that you decide what’s important to you when buying a car, whether it’s used or new.
Whichever you go for, make sure you protect yourself in the event of unexpected vehicle failure by getting a quote with Warranty Direct today!
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