Can the 105 year-old make a comeback?


Veteran Member
Apr 24, 2000
2012 TDI 4dr GOLF 6sp MAN
Diesel takes on the hybrid engine.

Can the 105 year-old make a comeback?
Last week we talked about the most fuel-efficient cars available for sale to the public – gasoline/ electric hybrids. Their high tech answer to our fuel and emission concerns has garnered a budding but loyal following among environmentalists and early adopters.

Still, the vehicles are only available from two manufacturers offering a total of three models – one of them selling a mere 2,000 units in a year. These numbers scarcely justify the considerable investment in research and development necessary for this new technology.

Buyers are equally cautions. Early adopters may love the vehicles but the price premium rule out the cars as true economy cars. Before the majority of consumers can seriously consider one the price has to drop and the technology has to prove that it will be around in the years to come.

Given all these hurdles it comes as no surprise that the Big Three – GM, Ford and Daimler-Chrysler are seriously considering an engine that has been around for decades – the diesel. The attractiveness of diesel engines is their greater efficiency and, in recent years, by significant technology improvements such as microprocessors to individually meter and inject fuel into separate intake valves.

The diesel engine has been around since 1898. Today it powers heavy trucks, transit buses, boats and almost all industrial equipment all over the world.

Although the Big Three all have diesel models in Europe none of them make it to this side of the pond - yet. Less than 0.1 percent of light vehicles in the US run on diesel fuel, whereas it is more than 25 percent in Europe. Diesel vehicle registrations account for almost a third of new European cars in 2000. Annual diesel sales have reached about 5.8 million and are expected to rise to almost 7 million by 2005. Some experts have even predicted that diesels will outsell gasoline powered cars in Europe by 2005.

Additionally, tax laws in all European Union (EU) countries, except the United Kingdom, currently favor diesel powered vehicles. On top of that some countries, including Sweden, Finland, Norway, and the Netherlands, also tax fuels based on their carbon content. These taxes favor diesel fuel over gasoline because diesel releases less carbon per mile of operation.

Although many of us can see the black plumes of exhaust from commercial vehicles everyday it may surprise many to find that diesels are low in greenhouse gas emissions. Unfortunately they do have higher emissions of nitrogen oxides and diesel particulates.

The good news is that particulate emissions from vehicles are expected to decline over the next decade. The EU will introduce more stringent standards for particulate emissions from light duty vehicles of 0.04 grams per mile. In California an even more restrictive standard is set to come in force in 2004, allowing only 0.01 grams per mile of particulate emissions. New particle traps being introduced by some European automobile manufacturers are set to achieve that standard –and more. Exhaust ‘scrubbers’ recently unveiled by some European manufacturers boast of black carbon emissions of only 0.005 grams per mile, half of the California requirement.

A more advanced (and cleaner) diesel engine, the common-rail diesel, is waiting in the wings. The common-rail diesel engine uses a special port to feed all fuel-intake valves precisely at the same time. This results in superior efficiency, improved fuel economy and fewer emissions. The downside is that this engine requires super-low sulphur-diesel fuel, which is difficult to find in the United States.

Clearly, the diesel engine will be faced with significant challenges to be accepted by North American consumers. Growing environmental concerns and the forecast of future improvements in diesel emissions must be matched by a view of similar advances for gasoline and hybrid vehicles.

Although hybrids are the flavour of the day, if economy is your goal you might find that 100 year old technology may actually be all you really need.

~ Pedro Arrais