EXPLORING THE RISE AND GRADUAL DECLINE OF DIESEL THROUGH THE DECADES

If you're like most people, you've never even touched that diesel button at the gas station. These days it's not unusual to see diesel-powered pickup trucks, but beyond that, its application is pretty much limited to the transport industry, at least in the US. It's being phased out in transportation, too, with California in particular aiming for a zero-emissions logistics sector by 2040. What happened to this fuel, once believed to be the savior of the car as we know it?

To really track the downfall of diesel, we'll need to go back to the start with...

A Brief History Of Diesel

First off, diesel doesn't work like regular gasoline, where combustion is initiated via spark plugs. Diesel engines work by combining compressed air with high heat and injecting fuel, which ignites spontaneously, pushing the piston into motion. This combustion method is inherently more powerful than using spark plugs and gasoline.

If you want to go all the way back to the start, diesel was developed by German inventor Rudolf Diesel in the 1890s. Technically speaking, "diesel" refers to the engine, not the fuel, as the first diesel engines ran on pretty much any oil the drivers could get their hands on. Peanut oil, kerosene, lubricating oil, and even gasoline.

The fuel we call "diesel" is produced from a broad range of sources from petroleum to animal fat and coal, and it wasn't really standardized until after World War II. A lot of diesel engines still run on anything but the diesel fuel you can get from the gas station. Many larger diesel engines are built to run on heavy fuel oils or run-of-the-mill unleaded.

Okay, enough science. Long story short, diesel's versatility and power make it an excellent choice for big-engine applications, from boats and trucks to trains and submarines. Diesel has also gained ground in the private automotive market and has occasionally been pushed as a viable alternative to gasoline.

Why Diesel Grew In Popularity (Especially In Europe)

If you live in the US, you may be wondering when the heck diesel ever grew in popularity. You could say that it started with Mercedes-Benz. They introduced the first diesel passenger car, the Mercedes-Benz 260 D, back in 1936 and the first turbodiesel passenger car, the Mercedes-Benz 300SD, in the 1970s.

The Mercedes-Benz OM617 engine that powered the 300SD was first developed in 1974, right around the peak of the oil crisis. The turbodiesel version of the engine was developed in 1976, and the sedan was finally released exclusively for the North American market in 1978.

In the meantime, diesel cars like the Volkswagen Golf launched in 1974, and the Peugeot 604, launched in 1975, offered drivers a way to get where they were going without having to stress about pump prices.

Diesel accounted for 2.5% of the European market in 1973, growing to 4.1% in 1975. You'd think that those numbers would cool off alongside the oil crisis, but by 1983, diesel made up 11% of all new car sales in Europe. Europeans enjoyed tax incentives that made diesel considerably less expensive than gasoline, making diesel passenger cars far more common in Europe than they are throughout most of the world. Meanwhile, in North America, Oldsmobile tried to market a line of diesel engines in the late 1970s and early 1980s, resulting in failure rates that saw the drafting of the first Lemon Laws and cementing in the American buyer's mind that diesel just wasn't a great choice for your daily driver.

Dieselgate: How The World Found Out That Diesel Is Dirtier Than We Thought

Starting in the late 1990s, it looked like diesel was entering a boom period. From 1999 to 2015, Mercedes, Audi, BMW, Alfa Romeo, and Volkswagen released a whole range of new passenger-car diesel engines, with many advertised as an eco-friendly alternative to gas-powered cars. Even Honda got in on the act, with a diesel-powered turbocharged Accord. And then, along came Dieselgate.

Put simply, Volkswagen was lying to us about just how clean-burning diesel fuel really is. The automaker installed cheater software in around 11 million cars worldwide, including half a million for the US market, to ensure that the cars would activate their emissions controls only during laboratory testing. The rest of the time, these cars would pump out about 40 times as much nitrogen oxide as they would in the lab.

The Environmental Protection Agency exposed the scandal, which turned out to be such an embarrassment that even Europe was starting to rethink the whole diesel thing. Some in the European Parliament and the London Assembly proposed that diesel engines be banned altogether.

Dieselgate specifically refers to the VW scandal, but a number of investigations around the mid-2010s proved that it was pretty much the entire automotive industry producing fishy data. The list of automakers that never cheated on a diesel emissions test is shorter than the list of automakers that did. Pretty much everyone was on the hook for fines, fees, buybacks, and recalls in the nine, ten, eleven figure range. VW, in particular, has paid out more than $33 billion in relation to the scandal.

The Death of Diesel

It's not hard to guess how the industry responded to a slew of diesel scandals throughout the 2010s. In 2017, Volvo announced it would be phasing diesel out of its passenger car lineup entirely. Mitsubishi followed suit in 2019, and Renault and Hyundai dropped their diesel engines in 2021. Between 2017 and 2022, diesel car sales dropped from 6.8 million a year to 1.6 million.

Sales numbers have remained relatively stable in the US, where most diesel-powered passenger vehicles are pickup trucks. Diesel cars still dominate West African highways, given that region's more permissive emissions standards. In Europe, there is a clear rise-and-fall, with a 55% new-car market share back in 2013, down to just over 13% in 2023.

There is no doubt that EVs and hybrids have contributed to the EU's declining interest in diesel, as well. EVs command a 24% market share in 2022, up from 11% just two years earlier. If you were attracted to diesel for its supposed eco-friendly attributes, switching to something with a battery pack is the obvious choice.

Notable Cars That Still Use Diesel, And Why

For the most part, automakers didn't hesitate to jump off of the sinking diesel ship. Even if you could produce a car that met the promised emissions numbers, you're releasing it against more stringent government oversight and declining public demand. But, to paraphrase Wesley Snipes in the superhero classic Blade (1998), some folks are always trying to ice skate uphill.

Mercedes has stayed true to diesel, with cars like the New-Gen E-Class E450d delivering an impressive 37 miles to the gallon. BMW squeaked the 640d in just before the buzzer, with a turbocharged inline-six delivering 38 MPG. The automaker released the last run in 2018 and then announced they'd be dropping diesel, too. The Porsche Panamera's diesel variant was discontinued with the third-gen launch in 2023, but the 2016 second-gen models, packing a 4.0-liter twin-turbo diesel V8, are still out there. These days, the top dog in the Panamera range is a hybrid.

Outside the luxury market, the fourth-generation Ford Focus ST was briefly offered with a diesel engine, while VW produced the Golf GTD, a diesel-powered GTI.

While diesel might not be as clean as Volkswagen told us it was, the fact remains that there are a lot of advantages to driving a diesel-powered car. Diesel engines are known for their durability, meaning fewer expensive repairs after 10 or 15 years of daily driving.

Diesel's torque output is hard for gasoline to match, it provides better fuel economy, and European automakers have a long history of working with diesel, so you've got a century of research and development that goes to waste if they all just drop the subject entirely.

And at the end of the day, there's still a demand for diesel-powered cars. As long as you can find someone willing to buy something, you'll be able to find someone willing to make it.

2024-06-16T05:27:53Z dg43tfdfdgfd