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It will come into effect in 2013, but manufacturers have already begun to turn out the first models with the new emission standards: these are the technical solutions chosen by a variety of producers


Fabio Quinto

Euro 6 is knocking at the door. More than a year earlier than for cars, the new European directive on emissions will come into force for trucks in 2013 for homologations and in 2014 for registrations. And the manufacturers are starting to raise the curtain on what will be the new generation of trucks that we will soon see on our roads, and primarily on the technical solutions that will be adopted to reduce emissions. To have some idea of the impact the introduction of Euro 6 will have on the environment, just take as a reference two of the main substances produced by vehicle exhausts, PM (particulate) and NOx. The former will go from the 2 g/kWh produced by a Euro 5 to the 0.4 g/kWh of a Euro 6. The latter will be halved, passing from 0.02 g/kWh to 0.01 g/kWh. Substantial reductions given that the change to the Euro 4 (in 2006) and then to the Euro 5 (in 2009) already implied a not inconsiderable design effort by the manufacturers. With the Euro 4 the "seven sisters" complied with European standards by choosing two different technical solutions: Selective Catalytic Reduction (SCR) and Exhaust Gas Recycling (EGR). In the first case, in order to operate the catalyst needs a urea-based additive (Adblue), and Iveco, Mercedes-Benz, Daf, Renault Trucks and Volvo Trucks focused on this. In the second case, urea was not needed and it was chosen by Scania and Man. With the arrival of the Euro 5, Scania and Man also adopted SCR. Now, with the Euro 6, manufacturers are opting for more complex solutions, in which both systems can cohabit and in which an anti-particulate filter could be added. The first to reveal its hand was Mercedes, with the presentation of the OM 471 engine that will equip the new Actros. It is a 12.8 litre, 6 cylinder generating between 420 and 510 HP. It will replace the current range of V6 engines and the current V8 will also go into retirement, leaving this configuration to Scania alone. To reduce emissions, Mercedes has combined EGR and SCR, with the addition of an oxidation catalyst, anti-particulate filter and a device for eliminating excess ammonia. Despite the greater technical complexity, according to Mercedes the new Actros Euro 6 (which will be available in Italy from end 2011) guarantees reduced consumption of 3% to 7% compared to the corresponding Euro 5 model.
Mercedes was immediately followed by Scania and the presentation of the new six cylinder 440 and 480 HP, which will be mounted in the current R and G Series in the second half of 2011. Here, too, SCR and EGR cohabit with the advantage of considerably reducing the consumption of urea. And also here the two systems are flanked downstream by an oxidation catalyst, an anti-particulate filter and a device for eliminating excess ammonia. The installation of the new components, according to declarations by the Swedish manufacturer, will not affect consumption because vehicle weight will increase by only 75 kg. The design of the Euro 6 version of the V8 appears to be more complex and is still ongoing.
However, it seems that Iveco's choice will go against the trend: SCR will not be combined with EGR but only with an anti-particulate filter and a catalyst. This is the "SCR only" technology which features optimized combustion systems and the post-treatment of exhaust gases. It was patented by Fiat Powertrain Industrial and has extremely efficient NOx conversion of 95%. A solution that should reduce weight and size and, above all, fuel consumption. It remains to be seen, however, how it will affect the consumption of Adblue. The protagonists of the change will be the Cursor 9, 11 and 13 engines in addition to the Tector 4, 6 and 9, with the debut of the new 11 litre Fiat Powertrain engine.
The other manufacturers appear to be coming later: at the Busworld show in Kortrijk with the debut of the first Euro 6 bus by Man, but we will have to wait until the middle of 2012 for trucks. It is probable that here, too, SCR and EGR will be combined as in the Scania cousins, both part of the Volkswagen group.
As for Daf, the Euro 6 versions are expected in 2013. In the meantime, the latest 13 litre Paccar Mx engine was presented and complies with America's EPA 10 regulation. The Exhaust Gas Recycling system is combined with SCR and this could be the solution that will be adopted also for the Euro 6 versions.
Volvo Trucks and Renault Trucks don't appear to be in any hurry: for the Swedes, the Euro 6 could come with the new Fh. And behind it should be Renault Trucks, although this probably will not be before 2013.
But apart from technologies, maintenance is also needed in order to keep emissions and consumption low. The level of toxic emissions is much higher from trucks that are not regularly maintained, which was revealed in a study by the AIRP Observatory on sustainable mobility. To contain the impact on the environment by road transport, it is necessary to adopt styles of driving that are eco-sustainable; check tyres regularly and, with regard to the latter, use retreads.

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