Apparently, the ADBlue tank uses up space + adds weight, so this
may be why Comfort DelGro refuses to buy SCR buses. Or its more
likely due to the massive numbers of buses they have, and the
problem of acquiring that much AdBlue, and the storage of AdBlue as
well. Apparently, if the OCs run out of AdBlue, they downrate
themselves to go at a lower power output of around
210PS (just like the CPU in your com when it gets too
hot) and to keep themselves in the Euro V emmsions , wasn't
it? So it could be a logistics thing, too.
Anyway, since SBST bought an OC, and Mercedes Benz prefers SCR,
wouldn't it be a hassle to procure AdBlue for ONE bus? Or do they
put the OC at AM and then go buy AdBlue from SMRT AMDEP? Or does
Mercedes Benz offer an EGR version of the OC, albeit with muted
engine power?
The additional weight tanken up by AdBlue equipment is
insignificant. For every 100L of diesel consumed by the
engine, about 5-8L of AdBlue is required. The AdBlue tank on
a bus usually holds around 40L and is adequate for well over
600km. Buses with EGR engines require larger, heavier
radiators to cope with the additional thermal stresses than an EGR
system delivers. The additional weight is therefore a
non-issue.
When an SCR engine runs out of AdBlue, the engine management
system will sense this and will operate the engine in 'limp mode'
meaning that power will be severely restricted.
Do remember than Volvo's B9TL EEV requires AdBlue as well.
Regards,
Dave
