The Mercedes-Benz bus range for travel and regular transport services is to feature even more environmentally friendly specifications in the future. Over and above the proven BlueTec 5 diesel technology, the buses are now being made available in EEV (Enhanced Environmentally Friendly Vehicle) versions.
The optional EEV emissions standard is currently the strictest European emissions standard, with limits which are below those of the Euro 5 standard. This translates into even lower pollutant emissions, thereby undercutting the Euro 5 standard in terms of particle emissions, for example, by around 30%, but without a fuel economy penalty. The most significant aspect of this result, however, is that it has been achieved solely by means of internal engine measures and without an additional particulate filter in the case of the Mercedes-Benz BlueTec engines. Previously the BlueTec engines were able to fulfil the optional EEV emissions standard through a combination of SCR (Selective Catalytic Reduction) technology and an additional diesel particulate filter. This system will also continue to be available.
Mercedes-Benz Citaro with EEV now also available without diesel particulate filter
Although the Mercedes-Benz Citaro city bus family already featured an EEV version, this was only available in conjunction with an additional diesel particulate filter. The new EEV technology without diesel particulate filter, meanwhile, provides operators a number of significant benefits compared with the previous solution. On the one hand, the cost of acquisition is lower, since no additional expense is incurred for the diesel particulate filter. On the other, maintenance costs are also reduced due to eliminating the need to clean the particulate filter, thus in turn increasing the availability of the bus for service operations. Fuel consumption may also be lower due to reduced exhaust gas backpressure. Thanks to the new EEV technology, the kerb weight is lower too, and, in the case of the Citaro, operators benefit from gaining additional space for three more seats.
Touring coaches now also come with EEV
A completely new development is the availability of EEV versions of Mercedes-Benz inter-city buses and touring coaches without diesel particulate filters. Previously the products on offer included Euro 5 engines in the inter-city bus and touring coach range. The new EEV range of products brings with it additional benefits for operators. Companies will be able to own an environmentally-friendly vehicle for only a slight extra cost, and at the same time will be able to make positive use of it as part of their marketing strategy. The purchase of an EEV vehicle helps to promote environmental protection without resulting in an increase in fuel consumption and therefore CO2 output. A final point, but by no means one to be underestimated, is safeguarding access into major European cities and conurbations in the medium and long-term. Furthermore, incentives may also be possible in transit countries, such as Austria for example, where reductions in road tolls may be available.
The technology to fulfil the optional EEV emissions standard is based on Mercedes-Benz BlueTec 5 diesel technology, together with the installation of a number of additional technological details. Basically the fuel injection has been changed, and the injection nozzle, piping and mounting systems redesigned. Additional exhaust gas aftertreatment via SCR is not necessary. In terms of maintenance, service life, fuel consumption and weight, the EEV solution for Mercedes-Benz buses is on a par with established BlueTec 5 technology.
EEV engines in Mercedes-Benz buses
The new EEV engine technology without additional exhaust gas aftertreatment via SCR is available for the OM457 hLA/LA and 926 LA engines.
Source: Daimler AG