Li 1986 Pierce Transit was one of the first public transit agencies in the U.S. to trade in its diesel and gasoline-powered buses for buses fueled by compressed natural gas (CNG). 27 years later, this pioneering Agency has just finalized a new contract with the local utility, Puget Sound Energy, to buy an even better fuel: the renewable compressed natural gas (R-CNG). This fuel is produced by Bio Energy Washington (BEW), from the biogases emitted by decomposing wastes at the vast 920-aere Cedar Hills Regional Landfill in King County, WA. According to BEW, it is largest landfill gas-to-pipeline quality gas facility in the nation. The landfill's proximity to an interstate natural gas pipeline made it possible to get the fuel to market.
143 of Pierce Transit's 155 buses now run on R-CNG, using the equivalent of about 3,600 diesel gallon equivalents (DGEs) a day. The R-CNG is cleaner than CNG, it generates virtually no soot emissions and decreases carbon on a lifecycle basis by almost 90% (compared to 23% for fossil natural gas). Yet the rate the Transit Agency pays for the fuel is roughly equivalent to the wholesale rate it paid for fossil CNG. According to Pierce Transit's CEO Lynne Griffith, this move was 'just the natural next step.' Pierce Transit has been nationally recognized as a clean fuel pioneer by the American Lung Association, the Department of Transportation and the Department of Energy's Clean Cities program, among others. The Agency now aims to convert its paratransit fleet (for the disabled) to R-CNG.
Having buses powered by CNG and ail existing CNG fueling station, the switch to R-CNG was simple and cost little - other than having to arrange a long-term fuel purchase agreement with Puget Sound Energy. By using R-CNG, renewable identification numbers (RINs) are generated under the EPA's Renewable Fuel Standard, providing additional financial incentive to utilize this ultra-low-carbon fuel. Pierce Transit also receives a rebate of about $1,000 a month, making the switch from CNG to RNG both environmentally and financially attractive.
Case study - Pierce County, Washington: home of the first public transit fleet in the country to run on renewable natural gas