Natural gas buses are much friendlier to the environment than diesel buses. Dedicated Natural Gas Vehicles (NGVs) also produce, on average, 70 percent less carbon monoxide, 87 percent less non-methane organic gas, and 87 percent less NOx than traditional gasoline powered vehicles.
A natural gas bus also uses less fuel. It makes more sense at this time for a city or national park to go with buses that run on natural gas for their transit systems rather than diesel buses. Most city transit buses, as well as national parks drive a relatively small route. This allows each bus to stay close to their fueling station at all times. One of the biggest drawbacks to compressed natural gas (CNG) vehicles is the fact that fueling stations aren’t evenly spread out across the country. The other drawback of a CNG bus would be the initial cost for the CNG fuel system. With the miles driven and the savings on the price of fuel, the positive far outweighs the negative for buying a CNG bus rather than a diesel powered bus.
Natural gas is much cheaper than both regular gasoline and diesel. Natural gas is still below $2 per gallon in many parts of the country. The price of gas and other fossil fuels continue to rise. “You're going to see exponential growth of CNG across the United States as gas prices rise,” said Jesse Toprak, an analyst for TrueCar.com. “The long-term tendency is for gas to keep going up, and if that happens, natural gas is going to emerge as a viable alternative. It's just a matter of educating the U.S. consumer that this is a cheaper, cleaner technology to use.” As companies evaluate all of the options and consider the tradeoffs, natural gas busses are the best overall choice.