These days diesel seems to be everywhere we look—but many people still hear the word and think of noisy, smelly vehicles. Today’s diesel, or “clean diesel,” offers an attractive combination of power and fuel economy and is becoming more popular as European manufacturers in particular embrace the technology. A number of Cartelligent clients are asking what the differences are between gas and diesel and which makes the most sense for their lifestyle.
Diesel vs. Gasoline
Gasoline and diesel fuel are both produced from crude oil. Each barrel of crude is refined into heavier and lighter components, the lightest is used to make gasoline, the next lightest is used for jet fuel, then diesel and the heaviest is used to fuel ships and power plants. Diesel fuel is denser and less volatile than gasoline and needs to be compressed to a very high temperature and pressure to detonate. This density results in 14% more energy per unit of diesel fuel than gasoline, making diesel vehicles inherently more efficient. Diesel engines also typically produce more torque (or rotational force) than gas engines which allows for quick acceleration. This makes diesel a fantastic choice for those who want to improve their fuel economy without sacrificing performance and drivability.
The greater pressure required by diesel combustion results in higher production costs for diesel engines, but also sturdier engines that tend to be more durable than their gas counterparts. Many diesel engines can go more than 200,000 miles. This often translates to a greater residual value when it comes time for resale and can often make up for the difference in upfront cost. Nine out of the ten diesel vehicles studied by the University of Michigan held their value better than comparable gas models and five showed an improvement above 10 percent.
Unlike gas engines, diesel engines are able to maintain their fuel efficiency at higher speeds. Many diesel engines far exceed the EPA fuel economy estimate (which is tested at no more than 55 mph). With that in mind, here are a few side-by-side comparisons of vehicles available in gas, diesel and hybrid models to illustrate the increased efficiency of diesel engines:
|Volkswagen Jetta||24 city / 32 hwy||30 city / 42 hwy||42 city / 48 hwy|
|Audi Q5||18 city / 26 hwy||24 city / 31 hwy||24 city / 30 hwy|
|BMW 5 Series||20 city / 30 hwy||26 city / 38 hwy||23 city / 30 hwy|
|Volkswagen Touareg||17 city / 23 hwy||20 city / 29 hwy||20 city / 24 hwy|
As mentioned above, the fuel efficiency attained by diesel engines can be much higher than these estimates. Road & Track recently found that the Mercedes-Benz E250 BlueTEC was actually more fuel efficient than the Toyota Prius!
In most California markets, diesel fuel currently sells for approximately the same amount as regular gasoline. Additionally, luxury vehicles usually require the more expensive premium gasoline. The University of Michigan found most diesel owners had savings between $2,000 and $6,000 over three to five years. The average Volkswagen Jetta TDI owner saved a little over $3,000 in a three year period over its gas equivalent while the Mercedes-Benz GL saved its owners more than $13,500 over the same time frame.
Diesel is becoming more and more available, but it still isn’t as prevalent as traditional gasoline. Nearly half of US gas stations now offer diesel fuel and this number will continue to grow as diesel vehicles gain popularity. In the meantime, it’s definitely worth checking for stations near your home and work before deciding on a diesel vehicle. Most navigation systems will also guide you to the nearest diesel station no matter where you are.
The increased efficiency of diesel engines gives them a significant head start on being greener than their gas equivalents. Burn less fuel, create less pollution. Additionally, modern “clean diesel” fuel has 97% fewer sulfur emissions than past diesel and 40% less than gasoline. Although diesel fuel creates approximately 13% more CO2 per gallon than gasoline, the greater engine efficiency of a diesel vehicle results in a net emissions savings.
Diesels are a strong choice for a number of Cartelligent clients. We typically recommend diesel vehicles to clients who drive a significant number of highway miles each year where diesel engines are at their most efficient. If you do a lot of stop and go city driving, a hybrid or electric vehicle may be a better choice.
For more information on diesels, or any other vehicles, give us a call at 888-427-4270 or get started today