Fuel efficiency – Stage IIIB/Tier 4i policy explained


On this page you can find some quick facts about Tier IV/Stage IIIB emissions regualtions. For a more detailed look at Volvo CE's postion please look at our Tier IV / Stage IIIB Q&A.

Q) What are Stage IIIB and Tier 4 all about?
"Stage IIIB" is EU legislation and "Tier 4 Interim" is US legislation, that together require diesel engines to reduce the effects on the environment of exhaust emissions. All engines greater than 130 kW manufactured on and after 1 January 2011 will have to comply by law. They require the reduction of particulate matter (PM) and nitrogen oxides (NOx). They also regulate emission levels of hydrocarbons (HC) and carbon monoxide (CO).

Q) Particulate matter?
Soot and oil residues.

Q) Are Stage IIIB and Tier 4 regulations the same?
Basically, yes.

Q) So the two regulations are interchangeable?
Each engine will be certificated for use only in the area of manufacture, meaning an EU Stage IIIB engine cannot be imported into the US and vice versa.

Q) How about other territories? Do they have similar laws?
Japan is working on introducing similar laws. Others are bound to follow.

Q) Will older machines be required to be upgraded?
Generally, no. But there will be some countries that require retrofit with "Best Available Technology" or BAT.

Q)  What new techologies are available?
There are a number of technologies available to help meet the new standards. The main ones you will hear being spoken about are as follows:

EGR: The main principle behind the technologies is Exhaust Gas Recirculation (EGR). The exhaust gases are treated before being expelled, with particulate matter (PM) and nitrogen oxides (NOx) being removed as part of the process.

DPF: A Diesel Particulate Filter (DPF) collects particulate matter (PM), oxidises it and removes it from the engine cycle.

SCR: Selective Catalytic Reduction (SCR) injects a benign chemical reagent into the exhaust gas flow and converts the nitrogen oxides (NOx) into harmless nitrogen and oxygen. In Europe, this reagent is called AdBlue and in the US, DEF (Diesel Engine Fluid).

Our engines will be using EGR/DPF technology, but not SCR at this stage.

Of course, these processes also require a finely tuned V-ACT engine and specialist fuels and lubricants. The third-generation Volvo EMS-2 (Engine Management System) constantly tunes the engine to ensure the processes are optimised, while ultra-low sulphur fuels and low-ash lubricating oils are essential for effective functioning.

Q) Are there further Stages and Tiers after this?
Yes, the programme of exhaust emission reduction began in 1996 and is set to be fully in place by the beginning of 2015.

For more information, click here to download a copy of "Exhaust Emissions Reduction".

Contact: Arvid Rinaldo