Which is more fuel efficient petrol or diesel?

Therefore, diesel vehicles can often go between 20% and 35% more in a gallon of fuel than their gasoline counterparts. According to Bell Performance and Road and Track, customers who drive many miles on the highway tend to prefer diesel engines, as they are more efficient on these roads than gasoline engines. Diesel fuel simply contains more energy in each gallon than gas fuel, making it more economical overall. Diesel engines are still more efficient than gasoline engines, but less so for those who are mainly engaged in urban driving.

Diesel cars also have more torque, which translates into better fuel economy along with more impressive acceleration. The difference in fuel economy between gasoline and diesel engines is quite dramatic. As a general rule, diesel cars use an average of 15 to 20% less fuel than their gasoline counterparts, especially on long motorway journeys. Using less fuel means that diesel engines also produce less carbon dioxide (CO), a key factor in the ongoing threat of climate change.

A comparison between diesel fuel efficiency and gasoline doesn't even come close. Diesel engines tend to have 25% to 35% more fuel economy than gasoline engines. Diesel engines get a quarter to a third better “gasoline mileage” than gasoline engines. A big part of the comparison between the diesel engine and the gasoline engine is the fuel efficiency figures.

Diesel engines are simply better in this department, as much as 30 or even 40 percent better, although modern direct-injection gasoline engines are catching up. But that's not the whole story. Diesel engines are still much more efficient than gasoline engines in converting fuel into mechanical energy. In fact, including the energy advantage of the fuel itself, diesel engines are up to 40% more efficient at doing so.

Both types of engines are classified as “heat” engines because they convert the thermal energy of the fuel into mechanical energy. But diesel engines have better thermal efficiency than gasoline engines, which means they convert more of the heat into mechanical energy and waste less on the environment. With advanced fuel economy and efficiency, diesel cars are cheaper to use than gasoline cars. They also tend to have higher resale value, especially larger vehicles.

This makes them an ideal choice for driving long distances. When it comes to efficiency, diesel engines provide more efficiency by using 15-20% less fuel compared to gasoline engines. Low-end diesel engine torque provides a much better on-road driving experience. However, the price of this efficiency is a higher premium compared to the gasoline variant of the same car.

Parts and components for diesel cars are also often more expensive due to the complex construction of diesel engines. A diesel engine runs very lean (much more air) and can suck in as much air as it wants, controlling power only by injecting more or less fuel. It creates more nitrogen oxides (NOx) inside the combustion chamber, but that has nothing to do with the composition of diesel fuel. Wondering what type of fuel will be most suitable for your next vehicle, is a question that has haunted many.

Because of all this, the fuel economy of a traditional hybrid tends to be greater than that of a gasoline-only or diesel-only car. Diesels cost more than gasoline cars, a fact that needs to be changed when it comes to talking about the money you will save on fuel bills. However, if you drive many miles on the road each year and plan to keep your diesel car for a long time, it may make sense to pay the premium upfront for the most efficient engine, especially when you consider your annual fuel costs. New propulsion systems, such as battery-powered electric vehicles and fuel-cell electric vehicles, are coming of age and becoming more cost-competitive, but new infrastructure is needed to improve their attractiveness and increase market acceptance.

For example, this allows a refinery to convert diesel fuel into gasoline fuel, based on gasoline demand. While the gap between the fuel economy of diesel and gasoline engines has been closing, the way diesel engines work provides an advantage that even the most sophisticated gasoline engines struggle to compete with. The high pressures inside a diesel engine, together with the fact that it doesn't “choke” the air it draws in, create greater fuel efficiency. Drivers who travel less than 10,000 miles on average each year will not be able to limit their fuel costs enough that a diesel engine makes financial sense, unless they rarely drive in the city or currently drive a vehicle that requires premium gasoline.

In some parts of London, petrol and diesel cars will be banned from running from the end of this year, to improve air quality, so it's not just about oil burners. Consumers consider diesel to be a dirty fuel, technological advances have made it a clean and environmentally friendly option for drivers who want a high-powered engine without limiting efficiency. The greater the pressure to which hydrocarbons are subjected before combustion, the more efficient the combustion will be. For years, the difference between diesel and gasoline prices has been one of the main reasons for buyers to opt for the former, but recently, diesel prices have not only equalized, but have often outpaced gasoline prices.

The tradeoff is that the exhaust is about 500 degrees C at that point, but the SCR is more efficient at 220-350 degrees C. .

Bethany Pesch
Bethany Pesch

Amateur music geek. Lifelong gamer. Incurable music trailblazer. Subtly charming organizer. Extreme internet evangelist.