PERFORMANCE AND COST CONSIDERATIONS While costing more to fuel up, me- dium- and heavy-duty diesel bus and truck engines generally outperform those powered with natural gas, though natural gas engines may perform well in less de- manding applications. Diesel engines are powerful enough at low speeds to haul heavy loads and climb steep hills, and their high fuel economy allows drivers to travel further between re-fueling. In addition, natural gas vehicles have driving range limitations because of the limited number of CNG and LNG refueling stations and limited capacity of on board storage tanks on Type A and C buses. As a result, natu- ral gas vehicles typically are now Type D, and they must return to a central facility for refueling. One gallon of LNG contains about 60 percent of the energy in a gallon of diesel fuel, and CNG contains even less energy per unit volume. Performance limitations of natural gas
engines suggest they may be a viable option in certain niches, at least in the short run. Much like the NGV vehicle growth within the federally-funded public transit system, according to the American Public Transit Association, 26 percent of all new transit bus orders in 2009 were for natural gas. A heavy-duty, natural-gas Type D, 72-pas-
senger school bus generally costs more than a Type C, 2010 EPA compliant diesel vehicle. One example of a conventional 72-passen- ger diesel school bus costs approximately $100,000, but a natural gas school bus costs more than $140,000, not counting the many state and school district component speci- fication differences. Tis can cause a price variance of as much as 10 percent in either a Type C or Type D school bus. LNG or CNG powered-vehicle prices
might decrease if the market for methane gas vehicles increases substantially. Only time will tell if our nation’s goal of lower- ing foreign oil dependence will influence school bus purchasing decisions. Neither diesel nor natural gas has a clear
cost advantage when it comes to fuel prices. While a gallon of LNG is generally half the cost of a gallon of diesel, natural gas contains less energy per unit volume. Natural gas may have tax credits available, but the certainty of those credits continuing is unknown.
Congress was debating the New Alternative to Give Americans Solutions Act of 2011, or NatGas Act to extend current incentives and rebates for another five-year period. Although natural gas can be produced
readily at competitive rates, the costs of supplying LNG/CNG often depend on transportation expenses. According to an article by NGVAmerica, there are about
1,000 NGV fueling stations across the U.S., and about half of them are open to the public. By way of comparison, according to the U.S. Department of Energy, there are over 170,000 retail gasoline fuel sites. Te incremental
costs of installing
natural gas stations can be substantial, re- portedly as much as $500,000, depending on the quick-fill or slow-fill process used.
KEEPING YOUR FLEET RUNNING AT PEAK PERFORMANCE KEEPS GETTING HARDER.
LUCKY FOR YOU, FINDING QUALIFIED TECHNICIANS JUST GOT EASIER.
With TransTechs on your team, you have a reliable, steady resource for top-notch technicians without the risk, headache, and cost of recruiting and employment.
TransTechs specializes in:
• Flexible staffing requirements • Customized recruiting and employment solutions • High volume recruiting for large projects • Dispatching mechanics to multiple locations • DOT, FMCSA & TWIC compliance • Human resources administration
Flex your technician workforce with TransTechs.
www.TransTechs.com 888-637-3776
www.stnonline.com 63
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84