Conserving Fuel and Reducing Emissions
At TriMet, we strive to conserve fuel and lower emissions to reduce our impact on the environment. Here's how we do it.
Energizing MAX
MAX Light Rail uses only electricity, and even supplies some of its own power through braking (similar to hybrid cars). With MAX factored in, you can be more than 10 times as fuel-efficient per passenger by commuting on TriMet instead of in the average car.
Burning less fuel
Burning less fuel means fewer emissions and a more sustainable transit system. We are one of the most fuel-efficient transit providers in the country, thanks to our creative operators and mechanics who keep finding new ways to conserve fuel.
- TriMet is the nation’s first transit agency to test and operate buses cooled by a NASCAR-inspired system. Traditional systems draw up to 50 horsepower off the engine, draining power and consuming fuel. The NASCAR system's electric fans use less engine power, resulting in approximately 5 percent better fuel economy. The system also significantly cuts maintenance time and costs and is safer to maintain. TriMet and our manufacturing partner, EMP, were awarded a Clean Air Excellence Award in 2009 by the United States Environmental Protection Agency for this pioneering effort.
- A drivetrain computer in the engine compartment of each bus saves fuel and improves driving safety. It monitors the engine, transmission and braking system, and uses the data to adjust acceleration, braking, traction control and fuel injection.
- In 2005, our maintenance crews boosted gas mileage on buses an extra 0.32 miles per gallon by adjusting transmissions, front-end alignments and steering control arms, and maintaining a set tire pressure. This saves about 500,000 gallons of fuel per year.
- Our bus operators are saving fuel by turning off buses while waiting at transit centers, instead of idling.
Using improved fuel
A TriMet employee fills a tank from the first official batch of ULSD biodiesel fuel.
Our buses use a cleaner burning biodiesel fuel blend. TriMet is the largest biodiesel user in Oregon.
The blend, including the petroleum-based share of the fuel, meets new federal standards for ultra-low-sulfur diesel (ULSD). It reduces emissions, especially carbon dioxide, carbon monoxide, sulfur dioxide and particulates (smoke).
Other benefits of biodiesel use include:
- Reducing greenhouse gases—the number one contributor to global warming.
- Reducing dependence on foreign oil.
- Moderating the volatile price swings of petroleum-based diesel.
- Helping to build the biodiesel industry.
Reducing bus emissions
Older TriMet buses to run 90 percent cleaner
We have retrofitted 45 older low-floor TriMet buses with high-tech filters that reduce exhaust emissions up to 90 percent, allowing them to run as clean as our new buses.
The filters, paid for and installed by Cummins Northwest, LLC, reduce both particulate emissions (soot) and unseen pollutants. With the retrofit, these buses run much cleaner than required by the Environmental Protection Agency for their model year. Emissions are reduced to levels comparable to those of brand-new models.
Cummins is providing the particulate filters, spare parts and installation for our buses, which have Cummins engines, at a cost of about $432,000. Cummins selected TriMet as part of a nationwide EPA decree to reduce emissions from diesel engines.
The filter installations are made possible by the use of new fuel that meets federal standards for ultra-low-sulfur diesel (ULSD), and also is a biodiesel blend. About a third of our fleet now has similar emission reductions.
Results from a long-term commitment
Emissions from TriMet buses already have been reduced in the last several years due to new pollution-control equipment, testing programs and cleaner-burning fuels:
- Even without the new filters, our buses emit 90 percent fewer oxides and particulates than they did 10 years ago.
- TriMet voluntarily tests buses for exhaust opacity (visible smoke) to comply with stricter California standards.