Clean Diesel – Diesel Technology

Snohomish County Reduces Emissions Through Diesel Retrofits and Biodiesel

March 2009, Green Fleet Magazine - Feature

by Lauren Fletcher & Lisajoyce Vergara

With the help of state grants, Snohomish County, Wash., fleet officials are aggressively tackling environmentally responsible practices, which include retrofitting diesel-powered vehicles and increasing biodiesel use throughout the fleet. 

132 Vehicles Retrofitted

Since 2005, Snohomish County has retrofitted 132 diesel vehicles with diesel oxidation catalysts (DOC), reducing greenhouse gas (GHG) emissions. Turning over the fleet with 2007 and newer diesel-powered engines, certified for biodiesel use, achieved additional gains in GHG reduction. 

In 2005, the County secured a grant from the Puget Clean Air Agency to retrofit 24 fleet vehicles with DOCs. In 2006, the state's Department of Ecology Heavy Duty Diesel Retrofit Program awarded the County a $187,800 grant, valid through June 30, 2009. The County used the DOE grant to retrofit an additional 108 fleet vehicles. 

To retrofit a diesel vehicle, a manufacturer designs DOCs for each specific engine/vehicle configuration. Once the County receives the DOCs, a local vendor schedules installations with county shop supervisors. To perform the installation, the original muffler is removed and the new DOC is bolted in its place. 

'Greener' Path Paved

Another element in the county's multifaceted greening effort is a long-term biodiesel conversion program. Currently, 33,000 gallons of B-20 (20-percent biodiesel, 80-percent diesel) are used in approximately 70 percent of county diesel-powered vehicles. In addition, the County is also replacing at least 15 percent of its non-law enforcement vehicles with biofuel or electric-powered units. 

In 2008, the County reduced its carbon emissions by approximately 925,000 lbs. through B-20 usage. On target to convert its entire diesel fleet to B-20 biodiesel by 2010, the County has pledged to convert to B-40 by 2014. A pilot test on B-40 will begin in 2012. 

"We have the opportunity to set the right tone for future generations to follow," County Executive Aaron Reardon said. "Whether through emission reductions, waste disposal, transportation, or recycling, we are setting Snohomish County on a greener path." WT

Comment On This Story

Comment: (Maximum 10000 characters)  
Leave this field empty:
* Please note that every comment is moderated.



Fleet Management And Leasing

Jack Firriolo from Merchants will answer your questions and challenges

View All

Grants & Subsidies

Alternative Fueling Station Locator

Alternative Fueling Station Locator

Find your closest station or plan a route. Locate biodiesel, electric, ethanol, hydrogen, compressed natural gas (CNG), liquified natural gas (LNG), and propane across America.

Start Your Search