Consumer demand for better fuel economy coupled with pressure on car makers to reduce carbon dioxide emissions is likely to result in diesels eventually accounting for half of all passenger cars sold in Europe, according to independent automotive technology provider Ricardo Consulting Engineers.

In terms of overall market size, four of the top six markets - France, Germany, Italy and the Benelux countries - continued to experience rapid growth last year achieving record levels of diesel sales.

Spain already exceeds 50 percent diesel penetration. Even the UK, the only European country to buck this trend over the past six years, showed signs of reversing its steady decline.

Ricardo concludes that a further increase from the present level of almost one in three sales (up from 14 to 32 percent penetration over the past 10 years) is likely before the end of the decade.

The consultancy says that improvements in diesel engine performance and driving characteristics are helping to drive the rapid growth of diesel engine sales in Europe.

Overall, diesel penetration across Europe in 2000 increased by 11 percent from the previous year's record to 4.76 million vehicles, representing a market share of 32.3 percent. For the first time, both France and Germany exceeded one million sales.

Sales of car-derived vans and light commercial vehicles up to 3½-tonne gross vehicle weight are already heavily biased towards diesel and in 1999 reached a new record level of 1.51 million units representing a penetration of approximately 90 percent.

France remains the largest market for diesel cars. In 2000, sales increased by 10.5 percent to 1.046 million vehicles taking diesel penetration to 49 percent.

Germany was the second largest market for diesel cars in 2000. Sales increased by 20 percent in line with the overall market to 1.03 million vehicles maintaining a diesel share of 30.4 percent. Germany is Europe's largest passenger car market.

Continued rapid growth helped Italy re-take third place ahead of Spain. Diesel sales were up by 19 percent to 814,000 vehicles and market penetration increased to 33.7 percent.

After nine years of significant growth in diesel sales, the Spanish market showed signs of stabilising at 733,000 with market penetration of 53.1 percent.

Total diesel sales in the Benelux countries increased to 445,000 with a market penetration of 38.6 percent. Belgium accounts for the majority of diesel sales and at 56.7 percent has the second highest diesel penetration in Europe.

Following six years of decline in the UK, 2000 saw the first signs of a reversal in this trend with sales increasing by 3 percent to 313,000 vehicles and market penetration increasing slightly to 14 percent.

Although the UK remains the only major car market where diesel fuel is more expensive than petrol, consumer demand for better fuel economy indicates that there is potential for an increase in the UK from this level.

Diesel penetration of the UK car market has previously been higher and peaked at 22.6 percent in 1994 - almost a percentage point higher than the penetration in Germany today.

The largest diesel penetration last year was 61.8 percent, a new record for any European country, which occurred in Austria. The Austrian market size, in 2000, was 191,000, a 6.1 percent increase on the previous year's figure.

Advanced technology is enhancing the desirability of the diesel engine.

Throughout Europe, technical developments have been dominated by the comprehensive move towards direct fuel injection in the design of all new engines. In addition, most manufacturers are increasingly using common rail fuel injection technology in preference to rotary or unit injector systems, principally because of the control flexibility and design simplicity that it offers.

Amongst the major players, the notable exception to this trend is the Volkswagen Audi Group (VAG), which is committed to using electronic unit injectors. EUI technology provides relatively high injection pressures, is flexible and is suited to high engine power output.

The principal drawback of EUI is the development cost for new engines. VAG is able to justify its investment in EUI technology due to its high production volumes and modular approach to engine ranges.

The company is the top producer and seller of diesel passenger cars in Western Europe and accounts for more than one in four (27.4 percent) sales.

Recent years have seen ever-increasing levels of power and torque output from new diesel engines, which are now available with maximum outputs reaching up to 240bhp (180kW).

It is expected that within five years manufacturers will be able to offer customers the same number of diesel options as petrol variants for each vehicle, further enhancing the desirability of the diesel car.

Future developments will include a trend towards smaller displacement higher power output diesel engines, which will ultimately use electrical power to boost vehicle acceleration.

The development of new technology such as the Flywheel Mounted Electric Device (FMED), which will improve engine starting and power generation, will assist in meeting new fuel economy and emission targets.

Of the five main tailpipe emissions, future legislation could potentially create a level playing field with diesel and petrol engines converging towards common standards. Inherently, diesel engines have lower carbon dioxide (CO2), carbon monoxide (CO) and hydrocarbon (HC) emissions.

Meanwhile, pressure for lower particulate and NOx emissions will see the introduction of a new generation of filters and oxidation catalysts, in some cases combined, which will start to appear by 2004 prior to the implementation of the next level of European regulations.

To view related research reports, please follow the links below:-

Gasoline & Other Fuel Additives to 2004

The world's car manufacturers: A financial and operating review