LOUISVILLE, Ky. — Volvo says its ability to eliminate active regenerations in 2010 engines "tips the scales" of the engine emmessions debate back SCR’s way.

In a major benefit for fuel economy and operating costs, Volvo trucks equipped with selective catalytic reduction (SCR) emissions control systems will not undergo driving or parked active regeneration of diesel particulate filters (DPF) during normal highway operating conditions.

Volvo’s U.S. EPA’10 emission systems integrate its SCR and DPF technologies and will instead employ only passive regeneration, based on extensive testing in customer fleets.

Passive regeneration of the DPF eliminates the need to inject diesel fuel into the DPF to oxidize accumulated soot, and results in reduced fuel consumption, reduced thermal cycling of expensive catalysts, and lower operating costs. It also simplifies vehicle operations by freeing the driver from having to keep track of when an active regeneration needs to take place.

“This is a huge development for our customers, since their drivers no longer have to monitor DPF status or worry about managing DPF regenerations – because a Volvo on-highway truck with SCR will not require active regeneration,” said Scott Kress, senior vice-president of sales and marketing. “Volvo’s advanced SCR technology removes a significant source of the trucking industry’s concerns with emission systems. The truck and driver are more productive, the fleet saves fuel and the environment benefits.”

Volvo currently has about 30 test trucks with 2010 engines in customer fleets operating with over two million miles of operation – with no active regenerations. In addition, another 23 Volvo trucks in an earlier North American SCR demonstration and test fleet have been driven more than 9 million miles without an active regeneration.

The ability to passively regenerate DPFs depends on having the correct concentration of nitrogen oxides (NOx) in the hot exhaust flowing into the DPF, since the NOx enables passive regeneration. By using SCR to eliminate NOx from the exhaust after it flows through the DPF, Volvo is also able to tune the engine for better fuel efficiency and better performance.

Customers who choose to spec a non-Volvo engine in a Volvo truck may still be required to perform active regenerations.

For a complete wrap-up of Day 1 at MATS, or a real-time account of Day 2’s events, check out Marco Beghetto’s blog.