By Andrew Littlefair on

Across the nation, a set of trends is converging that has left many metropolitan transit authorities facing bigger challenges than ever before. One of these convergences is the fact that in many cities public transit ridership have risen to an all-time high at the very time that fuel costs have stretched budgets to the breaking point. This has left many transit authorities seeking ways to trim costs and maximize efficiencies so they can continue to provide first-rate service to passengers who are sometimes completely dependent on public transit to reach work, school and healthcare appointments.

Another noteworthy trend is that in every major metropolitan area, except Chicago, the number of transit commuters increased outside urban cores but decreased inside them. This means that transit authorities will need to decide how to fund fleets that cover more miles, have a changing base of passengers and manage this evolution within tight cost constraints.

Dallas is one of the largest cities in Texas, boasting a population of 1.2 million. And many of the city’s residents rely on public transportation. Dallas Area Rapid Transit (DART) was seeking ways to serve their ridership as economically as possible while managing their environmental footprint. In a letter posted in METRO Magazine’s Green Views blog, DART president and executive director Gary Thomas shared his perspective on DART’s decision to transition their entire bus fleet to CNG.

SEE ALSO: Switching Fleet to CNG Was Carefully Weighed Decision for DART

DART Chooses Clean Energy Natural Gas After Evaluating Alternative Fuels

This decision was made after careful analysis which included comparing and contrasting numerous alternative fuel options including “clean diesel” which didn’t offer significant greenhouse gas or fuel-cost reduction, and diesel/electric hybrid buses which were cost-prohibitive. CNG offered both a reduction in greenhouse gas emissions and fuel cost savings.

Clean Energy Powers DART with CNG & Builds Fueling Stations

To help DART make the switch we agreed to do what we do best: design and build natural gas fuel stations at DART’s bus operating facilities. In total, we designed and built four CNG fueling stations and performed the necessary facility modifications in 2012 for the entire transit and par-transit—typically minibuses—fleet. When this transition is completed at the end of 2015, DART will be running 425 CNG buses and 200 par-transit vehicles. In February 2014 we announced an agreement to fuel DART’s natural gas fleet for many years to come.

“Natural gas is being taken as a serious transportation fuel, and the main reason that has happened is price,” said T. Boone Pickens, legendary energy expert and Dallas resident.

And this price difference has triggered a lot of interest in the migration to natural gas vehicles, which in 2013 offset the use of about 400 million gallons of gasoline.

Fuel Savings of Over $120 Million Over 10 Years

For transit authorities who have already made this switch, and for others like DART, the migration to natural gas has resulted in real savings, both monetarily and environmentally. With everything in place, DART will see savings of approximately $120 million over the next 10 years from fuel savings alone.

Substantial Reductions in Greenhouse Gases

The deployment of a natural gas fleet onto the streets of Dallas will also have an immediate and positive impact on the local environment. In fact, when fully deployed, DART is expected to use approximately 7 million GGEs of CNG per year, which reduces greenhouse gases by 14,749 metric tons, the equivalent of taking 3,045 cars off the road.

And don’t forget one of the most important benefits that goes with this transition, since diesel fuel is often imported and natural gas is domestic: American jobs.

“When DART buys diesel fuel, those revenues leave the region, where compressed natural gas is actually produced within the region,” noted Michael Morris, director of transportation for the North Central Texas Council of Governments.

Certainly, nothing speaks louder than success, and the cost savings and consumer satisfaction that are emanating from the switch from diesel to cleaner natural gas is catching the eye of decision-makers across the nation. We agree with Mr. Pickens that “we are at a tipping point now where we are going to move to natural gas and we’re going to move away from diesel.” As Mr. Pickens is fond of saying, “diesel is dirty fuel.”

SEE ALSO: Transit, the Cleanest Ride in Town