Fuel buses

In 1987 Seatde Metro purchased 10 new American built M.A.N. coaches powered by methanol. Six GM buses powered by DDC methanol engines entered revenue service at Triboro Coach in Jackson Heights, New York, 2 GM buses in Medicine Hat Transit in Medicine Hat, Manitoba, and 2 Flyer coaches in Winnipeg Transit, Winnipeg, Manitoba, Canada. An additional 45 DDC powered methanol buses were introduced in California as indicated by Table 4. Figure 11 shows the distance accumulation of alternate-fueled buses in the four California transit properties. 

Wang, W. G., N. N. Clark, D. W. Lyons, R. M. Yang, M. Gautani, R. M. Bata, and J. L. Loth, Emissions Comparisons from Alternative Fuel Buses and Diesel Buses with a Chassis Dynamometer Testing Facility, Environ. Sci. Technol, 31, 3132-3137 (1997). 

Safe Operating Procedures for Alternative Fuel Buses, 1993 Transportation Research Board National Research Council 2101 Constitution Avenue, N.W. 

Tzeng, G-H., Lin, C-W., Opricovic, S. (2004). Multi-criteria analysis of alternative-fuel buses for public transportation. Energy Policy (in print). 

This particular reaction may be important when sampling exhaust from methanol-fueled combustion sources. For example, significant concentrations (46-69 ppm) of methyl nitrite have been reported in the exhaust of a methanol-fueled bus (Hanst and Stephens, 1989). Such large concentrations would be of concern if... 

Determined the maximum-recorded overpressure created by a 13 SCFM hydrogen leak under the full-scale model of the front half of a hydrogen-fueled bus was less than 0.03 psi. 

See Nutmeg CT Transit Fuel Bus project NFCBP factsheet at http //www.nrel.gov/hydrogen/pdfs/... 

The first methanol bus in the world was placed in revenue service in Auckland, New Zealand in June 1981. It was a Mercedes O 305 city bus using the M 407 hGO methanol engine. This vehicle operated in revenue service for several years with mixed results. Fuel economy on an equivalent energy basis ranged from 6 to 17% mote than diesel fuel economy. Power and torque matched the diesel engine and drivers could not detect a difference. ReHabiUty and durabihty of components was a problem. Additional demonstrations took place in Berlin, Germany and in Pretoria, South Africa, both in 1982. 

The biggest potential use of the cetane-improver approach may be in vehicle retrofits where for environmental reasons bus and tmck fleets may be requked to convert to cleaner burning fuels. 

M. D. Jackson, C. A. Powars, K. D. Smith, and D. W. Fong, "Methanol-Fueled Transit Bus Demonstration," Paper 83-DGP-2, American Society of Mechanical Engiaeers. 

M. D. Jackson, S. Uimasch, C. Sullivan, and R. A. Renner, "Transit Bus Operation with Methanol Fuel," 5ME Paper 850216, SyPE Int. Congress and Expo. (Detroit, Mich., Feb. 25—Mat. 1, 1986) Society of Automotive Engineers, Warrendale, Pa. 

S. Uimasch and co-workers, "Transit Bus Operation with a DDC 6V-92TAC Engine Operating on Ignition-Improved Methanol," SME Paper 902161, (SP-840), SME Int. Fuels and Eubricants Meeting and Expo. (Tulsa, Oklahoma, Oct. 22—23,1990). 

BaUard Power Systems, the leader in the manufacture of PEEC stacks, has sold at least fifty 3- to 5-kW units worldwide. BaUard is involved in a program in Canada to demonstrate a 120-kW PEEC stack to power a transit 20-passenger, 9752-kg bus. Eor this demonstration, on-board compressed hydrogen, sufficient for 150-km range, is the fuel. 

Ballard Power Systems, in conjunction with the province of British Columbia and the government of Canada, have converted a diesel bus for Vancouver, B.C. Transit (43). This 9.1-m vehicle is powered by a 105-kW fuel cell. Gaseous hydrogen, stored on board the bus in DOT-approved glass-wound composite cylinders operating at 20.7 MPa (3000 psi), provides the necessary fuel requited for the 150-km projected vehicle range. 

M. Samsa, Potentialfor Compressed Natural Gas Vehicles in Centrally-Fueled Automobile, Truck and Bus Fleet Application, Gas Research Institute, Chicago, 1991, pp. 44-61. 

Most urban rail service is electric-powered and most urban bus service is diesel-powered, although diesel rail and electric bus operations do exist, as noted above. The efficiency and environmental impacts of electricity depend gi eatly on the source of electric power. Although electric vehicles produce no tailpipe emissions, generation of electricity can produce significant emissions that can travel long distances, Eor example, coal-powered electricity plants produce particulate emissions that travel halfway across North America, Urban buses also can be powered by a variety of alternative fuels. 

Traffic signal preemption and other technologies that seek to speed transit can have a similar effect. Faster bus travel means less fuel consumption per vehicle distance traveled. However, faster transit seiwce increases demand for transit, potentially increasing the transit load factor. 

The carbon footprint of transport fuels has been analyzed in several studies starting from 1990. One of the most important is the study realized by Sheehan et al. [13] at National Renewable Energy Laboratory of the United States.This is an LCA study that includes the impact of C02 emissions. Most important operations belonging to the petroleum diesel product system include crude oil extraction, its transport to an oil refinery, crude oil refining to diesel fuel, its transportation to the user, and its use in a bus engine. 

The Hydrogen Research Institute in Canada has developed and tested a stand-alone renewable energy system composed of a 10 kW wind turbine, a 1 kWpeak photovoltaic array, a 5 kW alkaline electrolyzer, and a 5 kW PEM fuel cell. The components of the system are electrically integrated on a 48 V DC bus [50]. 

As an added benefit, the city expects to save money with the simulators, because the new system reduces the amount of training time in an actual bus—saving on parts, fuel, and other operating expenses. 

There have also been revivals of the steam car. Robert McCulloch, the chain-saw millionaire, spent part of his fortune on a steam prototype, called the Paxton Phoenix, between 1951 and 1954. William Lear of Learjet fame, spent 15 million in 1969 on a turbine bus and a 250-horsepower turbine steam car. Both used quiet, efficient steam engines although the bus had reliability problems and poor gas mileage. Lear also tried to enter a steam car into the 1969 Indianapolis 500. The British firm of Austin-Healey was also working on a steam car in 1969. It had four-wheel drive. However, even prosperous entrepreneurs like McCulloch and Lear found that they lacked the means and support structure to successfully mass market a competitive car. Alternative power systems would have to wait until air-quality regulations resulted in some breakthroughs with hybrid and even fuel-cell cars. 

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