Less (emission) is more

The prospects of higher costs and bigger engine compartments seem to be the biggest concern for engine manufacturers as they adapt designs to comply with increasingly stringent emissions requirements.

Product marketing manager for Perkins, Tim Cresswell, says, "Firstly, it's the packaging of the equipment on the machines without grossly inconveniencing people and also retaining machine serviceability. The other challenge is the cost of installing engines, with most manufacturers talking about increases of between 50 and 100%. It's not going to be cheap."

Perkins said it would use technologies similar to those its parent, Caterpillar, already uses for on-highway applications in the US to comply with emissions standards. The company said that increased use of particulate filters and after treatment systems could reduce costs.

Other engine manufacturers are also revealing their design approaches to meet requirements. Cummins will use diesel particulate filter (DPF) and exhaust gas re-circulation (EGR) systems. Other engine features will likely include variable geometry turbochargers, advanced electronic controls, and high-pressure, common rail fuel systems.

Meanwhile, several engines from John Deere Power Systems, in its Power Tech E, M, and I ranges and rated less than 75 kW, are already Stage IIIB compliant. The company's approach has been to optimise combustion, and it is also considering "...a number of after treatment technologies".

Driving ongoing efforts to reduce emissions is the next set of regulations, Stage IIIB/Tier 4, which come into effect in January 2011. Their objective is a 90% reduction in particulate emissions. Source legislation also mandates a 45% reduction in hydrocarbon oxides (NOx), which rises to a 90% reduction by 2014.