Photographs can be seen in our Volvo Gallery

---

The diesel engine makes a strong comeback with better combustion and an automated particulate filter

10 June 2006

Today’s improved combustion and particulate filter make the diesel a fuel-efficient option with low emissions. Volvo Car Corporation offers a wide range of diesel engines for all of their car models, and a particulate filter that reduces emissions by approximately 95%. Meanwhile, carbon dioxide emissions are about 20% lower than those from petrol.

A revolutionary conventional fuel
Fossil fuels are used for 98% of the vehicles in traffic today, and they will remain the main energy source for years to come. Therefore, it is important not only to focus on renewable fuels, but also on lowering the fuel consumption and emissions from cars run on conventional fuels. Volvo Car Corporation offers a wide range of diesel engines for all of their car models. Today’s diesel engines are equipped with diesel particulate filters as standard on most markets, with several benefits for the environment. Particulate emissions from the modern diesel engine are extremely low, and carbon dioxide emissions 15-20% lower compared to petrol.

The proportion of diesel engines in some European countries, and in some vehicle groups, is as high as 90%. In Sweden, diesel engines increase more in popularity than anywhere else in Europe. New vehicle taxes, based on carbon dioxide emissions, and tax reduction for diesel cars with low particulate emissions have made the number of diesel driven cars in Sweden increase from below 10% to close to 20%. Gradually replacing petrol driven cars with diesel driven ones is an efficient way to help reduce total carbon dioxide emissions from the traffic sector.

Volvo S40 1.6D is the most fuel-efficient Volvo ever - 4.9 litres per 100 km
The Additive Diesel Particulate Filter (ADPF, se below) is currently available for the Volvo S40 and Volvo V50 1.6D. The Volvo S40 1.6D is a four-cylinder 1.6-litre diesel engine (109 bhp) with a fuel consumption of 4.9 litres per 100 kilometres. That makes it the most fuel-efficient Volvo of all times. The turbocharged diesel engine is made of die-cast aluminium and is also equipped with a common-rail direct injection system. Volvo S40 1.6D represents cutting edge technology that gives smooth performance, low emissions and low fuel consumption. The torque is high over a wide range of revs to deliver high power under all driving conditions. Low engine-weight contributes to the fuel-efficiency and allows a sporty driving-setup. The Volvo S40 1.6D is designed to be compact but feel like a large car, with power and performance to match.

The Additive Diesel Particulate Filter (ADPF)
Volvo Car Corporation’s additive diesel particulate filter (ADPF) captures soot particulates as well as ashes from unburned material from the exhaust. The accumulated soot particulates are automatically burnt off at regular intervals, every 300-500 kilometres depending on driving conditions and type of driving. This process takes about ten minutes and goes entirely unnoticed by the driver. Overall, the level of unburned soot particulates from the exhaust pipe is lowered by approximately 95% compared to a system without the ADPF. This means a significantly reduced impact on the environment.

The A in ADPF, the additive, is a catalytic solution that permits a lower activation temperature for burning off the soot particulates in the filter. The additive is a cerium/iron based solution that is filled in a special tank that holds approximately 1.8 litres. The consumption of the additive is low and the tank is filled up as a part of regular service.

Running on diesel
The diesel engine has made a technical revolution in the past 15 years. In 2005, regulated emissions of hydrocarbons and nitrogen oxides were 95% lower than in 1990. During the same period, carbon monoxide emissions were reduced by 98%. Modern diesel technology includes the common-rail direct injection system, with a high-pressure fuel pump and a pressure accumulator. Combustion is initiated by pilot injection, which results in gentler combustion, lower emissions and less noise. This also means excellent acceleration, as well as high cruising and top speeds.

Environmental gains
Diesel engines are generally more fuel-efficient than petrol engines, which favours both the environment and the driver’s economy. The additive diesel particulate filter eliminates approximately 95% of hazardous particulates. That reduces the concentration of large and small particulates to the same level as in a petrol engine, or lower. Volvo S40 1.6D emits 0.001 grams of particulates per kilometre, which is only a fraction of the statutory limit of 0.025 g/km. Carbon dioxide emissions are 15-20% lower compared to those from petrol.

---