Fuel concerns

Stage IIIB of Europe's off-highway engine emissions laws will start to come into force from the start of 2011. This next step in the legislation will see particulate matter (PM) pollutants cut by around -90% depending on the engine power band.

In addition to engine systems such as cooled exhaust gas recirculation (EGR) and Selective Catalytic Reduction (SCR), a significant portion of equipment manufacturers are likely to use Diesel Particulate Filters (DPF) to comply with Stage IIIB. These after-treatment devices use a physical filtration process to trap the particulates and then either continuously or periodically burn them off to regenerate the filter and stop it getting clogged.

Fuel Requirements

But the engine technology is only part of the story. The generation of particulates is directly linked to the sulphur content of the diesel being burnt in the engine. So in order to function efficiently, DPF systems require engines to be run on ultra low sulphur fuels, which is to say around 10 parts per million (ppm). At present there is no harmonised European law or standard for the sulphur content of off-highway fuels, and levels can be as high as 2000 ppm.

Recognising these issues, the European Commission's DG Environment will draft an amendment to the Fuel Directive (98/70/EC), which at present outlines a plan to introduce 50 ppm sulphur off-highway diesel by the end of 2009, moving to 10 ppm sulphur content by the end of 2011.

However, CECE and its partner associations in the sector - CEMA, which represents agricultural equipment manufacturers and EUROMOT, the engine manufacturers' association - believe this timetable will delay the implementation of Stage IIIB technologies, prevent after treatment systems working to their highest efficiency, and cause unnecessary burdens to the industry because European laws would be out of step with the US.

Overlap

The current timetable would see DPFs having to cope with 50 ppm sulphur fuel during the year-long period when the first powerband of engines will have to comply with Stage IIIB (from the start of 2011), but before 10 ppm fuel is introduced at the end of that year. This will shorten the life of DPFs, increasing the downtime of equipment and could mean much larger and more cumbersome after treatment systems would be required.

There is also the practical issue of ‘flushing' old high-sulphur fuel out of the distribution network. Many construction machines are fuelled from large tanks on remote sites, which can not be allowed to become completely empty, as this would bring work to a standstill.

A quick calculation shows that if such tanks are refilled when they are 90% empty, it will take five fillings with 50 ppm sulphur fuel to make the transition from 2000 ppm, and a further three fillings with 10 ppm fuel to reach the final concentration. CECE and its partners' experience shows it takes two years for a complete transition between fuel grades.

Industry Position

CECE and its partners believe the best way to achieve the transition to ultra low sulphur fuels is to introduce 10 ppm diesel fuel, compliant with EN 590, to the off-highway market from January 2009 - three years earlier than is envisaged under the current timetable.

While an intermediate stage of 50 ppm is not necessary from the engine and equipment industry's point of view, it is recognised this might make the transition easier for the petroleum industry. Introducing 50 ppm fuel in January 2009, as is currently suggested, would be acceptable, provided 10 ppm fuel was available from mid-2010 - six months before the introduction of Stage IIIB and 18 months earlier than is currently being suggested.

Dye Marker

The equipment industry also believes the Fuel Directive presents an excellent opportunity to establish a harmonised European law for the dye colours used to distinguish between different types of fuel. The current situation of different member states using a variety of dye marker colours leads to misunderstanding, the risk of misfuelling and fines for equipment users when working outside their national borders.

CECE and its partners are proposing that three standard colours should be introduced across Europe - one for heating oil, one for off-highway diesel and one for on-road diesel.