Alpina D3 Bi-Turbo Saloon and Touring
VHS or Betamax? Blu-ray or HD-DVD? Sometimes society comes to a fork in the road where it has to choose one form of technology over another. With the examples given here, it's usually the porn industry that makes up our minds for us. But now we have the opportunity to do the right thing for our transportation situation.
There's no denying that we need to cut fuel consumption and reduce emissions-for reasons such as global warming, reliance on imports of foreign oil, smog-filled cities, rising prices of crude-even if there are occasional dips, oil will only become more expensive in the long term, just because of supply and demand. So now, right now, is the time for diesel. Imagine never having an Internet, then going straight into fiber-optic broadband access. That's what America can feel like, because the Europeans have taken diesel technology and brought it to such a state of maturity that we can just reap the rewards.
And what rewards they are: better mileage (up to 40 percent less thirsty than a gasoline equivalent), fewer noxious gases, great reliability, and gobs of torque. If anything can wean America off gasoline, it's modern, clean diesel. Fans of European cars are in the vanguard, because the good stuff is all German, from the humble VW Jetta to the massive Audi Q7 TDI, by way of the BMW 335d and Mercedes-Benz Bluetec vehicles. That's just what is available now; the future looks even more promising.
BMW Vision Efficient Dynamics Concept
1. Why diesel is better than gasoline
Diesel has a greater energy density. On average, one gallon contains 147,000 BTU, compared with 125,000 BTU in a gallon of gas. It's also less prone to evaporation, an important attribute when storing and transporting.
Biodiesel: No trees were impacted, carbonized and left to fossilize for millennia in the making of this product. Scientists are looking into various sources, such as a rare fungus from Patagonia, but fuel from algae seems to be getting most of the attention at the moment. This humble seaweed can be farmed without competing for food resources. And if there's a spill, it wouldn't create much environmental impact-it's biodegradable. As a nice side effect, this fuel might even eliminate the need to deal with Middle Eastern countries that have appalling human rights records.
The United States Department of Energy has calculated that algae-derived biofuel from 15,000 square miles could meet the country's annual gasoline needs. That area is about a seventh of the land given over to corn production. Fuel from algae can even be used for jet engines. Society is accustomed to being mobile and biofuel looks like it can keep things that way, providing the cost can be manageable. In these early days, biodiesel is still expensive to produce, but governments and private companies are funding research into making it a viable commodity.
2. Why Diesel Is Better Than Electric Cars
How long does it take to fill a car's fuel tank? About eight minutes? How long does it take to recharge a Tesla completely? More like eight hours. No one is ever likely to suggest taking an EV on a road trip-not for a long time, at least.
Diesel engines are renowned for their longevity. It's not unusual for a Mercedes-Benz oil-burner to reach 350,000 miles. Lithium ion battery packs? Not so much. They can only be recharged a finite number of times until they have to be replaced. There is no exact figure, but think about those iPods and laptops that have needed new batteries after a couple of years. The cost of a car-worthy Li-ion pack is around $15,000. And this is still assuming the technology will progress far enough and quickly enough to deal with the problems of heat and exploding cells. Toyota is sticking with nickel metal hydride for its hybrids, likewise Porsche and its Cayenne hybrid, because Li-ion isn't where it needs to be.