|Past, present and future alternatives
(Note to the reader: The basis of this article was an essay written in early 1996 for a transportation geography course at the University of British Columbia. Some updates were made in February 1997. Correspondence, especially on the efficiency issues of trolleybuses and fuel cell buses, is welcomed.)
Electric trolleybuses have operated on Vancouver’s streets for close to 50 years and today carry one-third of BC Transit’s revenue passengers in Greater Vancouver. Basic statistics on the system are given in Table 1. However, their future is in question as a result of technological change, rising capital costs and discontinuities in the management of the system. Can alternative fuels such as compressed natural gas and hydrogen fuel cells provide the same environmental and rider benefits as the trolley system at lower cost?
|Overhead wire||305 km|
|Peak fleet requirement||202|
BC Transit, once a staunch supporter of the trolleybus, has not fully committed itself to continuing trolley operation once the current fleet is life-expired around the year 2004. Glen Leicester, BC Transit’s Executive Director of Strategic Planning, in communication with the author, says BC Transit is committed to maintaining the current system but that other proven, less costly technologies will be considered for its eventual replacement. BC Transit policy is that any replacement technology must also meet the objectives of producing no pollution from the vehicle and be quiet. The decision between trolleys and other alternate fuel technologies is projected to be made between the years 2000 and 2002. The only non-trolley vehicle to-date which can meet these goals is the Ballard fuel cell bus, although, as discussed later in this paper, the fuel cell bus has a number of drawbacks to be considered.
Early development of the trolleybus took place in Europe with the first experiments of a road vehicle drawing power from overhead wires taking place in Germany in 1882. Early models were based on streetcar technology and, being heavy and unwieldy, were not popular. In 1926 lightweight bodies designed for gasoline powered buses began to be modified to operate as trolleybuses and their popularity increased rapidly. Trolleybus service began in London in 1931 with the fleet reaching 1764 vehicles, the largest in the world, by the start of World War II.
The first North American use of trolleybuses was in 1928 in Salt Lake City and by the end of the 1930’s there were approximately 2800 trolleybuses operating in North America. Switching to trolleybuses allowed streetcar operators to get out of often onerous street maintenance obligations while the lighter weight of trolleybuses provided better performance. Reduced infrastructure requirements and greater manoeuvrability made conversion from streetcars even more attractive. In 1940 trolleybuses were operating in 60 U.S. cities and towns with the number of vehicles operated peaking at 6500 in 1950.
The decline of trolleybuses in the following years has been attributed to a number of factors. When maximum efforts were being made to accommodate the automobile, trolleybuses were seen as not flexible enough to operate in mixed traffic. As the number of trolleybus systems fell, vehicle costs increased relative to motor buses. Eliminating the cost of overhead maintenance was given greater priority than the non-remunerative passenger comfort and environmental advantages provided by trolleybuses. Despite these factors, trolleybuses remained popular in Switzerland, Eastern Europe, the USSR and China (Vuchic 1981).
In the 1970’s oil shortages, high oil prices and environmental awareness brought a reappraisal of the trolleybus and a renewed commitment to the mode by the few North American cities left using it. The five remaining American systems (n1), plus Toronto and Hamilton, renewed their fleets in the 1970’s (Rafter 1995). Edmonton and Vancouver followed with wholesale fleet replacements in the early 1980’s. Impending clean air regulations in the U.S. brought a renewed interest in the mode in the late 1980’s and early 1990’s and new systems were planned in Los Angeles and Sacramento (APTA 1992). Changing economic circumstances brought a halt to hopes for these new systems while hostile management and poor maintenance in Toronto and Hamilton succeeded in terminating trolleybus service in those two cities.
The first operation of trolleybuses in Vancouver was in December 1945 when a trolley coach brought up from Seattle by the B.C. Electric Railway Company provided 10 days of free rides from Burrard and Hastings to Alberni and Bidwell streets via Pender Street. Victoria had operated a similar experiment in October of the same year (Ewert 1986). While trolleybuses never again operated in Victoria, they were adopted on a large scale in Vancouver with revenue service on the new Fraser-Cambie line beginning on August 16, 1948. B.C. Electric provided the service with trolleybuses designed by the Brill company of Philadelphia and manufactured in Canada by Canadian Car and Foundry. Lines were added rapidly as trolley coaches replaced streetcars and by the end of 1949 168 trolleybuses were in operation in Vancouver. This “Rails to Rubber” programme had been accelerated by the 1948 decision that the new Granville Bridge, providing access to the west side of the city, would accommodate rubber-tired vehicles only. The conversion programme was complete in June 1955 when the Hastings East trolley coach line opened, replacing Vancouver’s last streetcar line which had ceased operation in April (Ewert 1986).
The trolleybus fleet peaked at 352 in the mid-1950’s when 25 second hand Pullman trolleys were purchased from Birmingham, Alabama in 1957, adding to the 327 Canadian-built Brill trolleys already on the property (Leicester 1993). Unfortunately the steel Pullmans were more than twice as heavy as the aluminium Brills, so making them difficult to manoeuvre. Within three years of their introduction the Pullmans were withdrawn and sold for scrap, a decision made easier because ridership growth was not as great as had been anticipated (Kelly 1990).
After a poor decade in the 1960’s, when many transit agencies in North America abandoned trolleybuses and the #10-Tenth route in Vancouver was converted to diesel operation as the first step in a plan to phase out the mode, the 1970’s brought a renaissance for the Vancouver trolleybus system. Fuel price increases and shortages, and a growing public environmental awareness, sparked a renewal of interest in trolleybuses in Vancouver. The dominance of hydroelectric power generation in British Columbia insulated BC Hydro’s trolleybus system from rising costs for fossil fuels. BC Hydro responded by acquiring second hand Brill trolleybuses for fleet expansion and parts supply from four Canadian cities which were eliminating the mode. The first extension in over 15 years opened in 1970 when the Cambie route was extended from 49th Avenue to 65th Avenue (Leicester, 1993). Other extensions were planned and public timetables from the mid-1970’s note that the diesel shuttle between the east end of the Broadway trolleybus route at Boundary Loop and Brentwood Mall was a temporary measure “until necessary arrangements can be made to extend trolley coach overhead eastbound to Halifax at Willingdon.”(BC Hydro 1976).
In 1975 BC Hydro began receiving 25 new Flyer E800 trolleys from the Flyer plant in Winnipeg, using reconditioned electrical equipment from second hand Brills. This allowed the retirement of the surviving original Brills after nearly 30 years of service (Kelly, 1990). Rough operation on the Flyers, caused by the poor modification of the propulsion equipment, combined with their narrow doors and the arrival of a new fleet of trolleys resulted in their withdrawal from service following Expo ’86. The bodies of the E800’s, not having been subject to the constant vibration from a diesel engine, remained in good condition and most were converted to diesels and operate to this day (Leicester 1993).
Although BC Hydro had tested a Swiss built articulated trolleybus in the 1970’s (Kelly 1990), the complete renewal of the fleet in 1982/83 was with 245 standard length Flyer E901A and E902 vehicles (n2). This followed a comprehensive economic evaluation of the trolley system in 1978 (Leicester 1993). The Flyers proved very troublesome and it was not until mid-1984 that the last Brill was retired, after 30 years of service (Kelly 1990). However, problems have persisted on the Flyers, especially with the electronic “chopper” control system which regulates the current flow to the motor and permits dynamic and regenerative electric braking. The politically influenced selection of a supplier for the chopper control system has plagued the Flyer trolleys, although many upgrades by BC Transit have greatly improved reliability (Schaefer 1996).
A number of extensions to the trolley system were undertaken in the mid-1980’s. Four extensions followed the opening of the SkyTrain rapid transit line in 1986, including a 3.0 km addition to the Kingsway route to Metrotown in Burnaby. A $1.5 million, 3.1 km extension in 1988 brought trolleybuses to the University of British Columbia for the first time and allowed the return of trolleybuses to the #10 route, as well as the subsequent extension of two other trolley routes to the campus (Leicester, 1993). The cost of the UBC extension was recouped within five years thanks to operating cost savings (Truscott 1993).
In early 1992, then BC Transit president Mike O’Connor suggested that BC Transit planned to expand the trolley fleet by purchasing second-hand vehicles from transit agencies, notably Edmonton Transit, which were expected to abandon the mode (Province 1992). Plans were also afoot to expand the trolley system by installing express wires on Broadway from Granville to Alma, create a new trolley route on Burrard Street between downtown and West Broadway, and to extend trolley overhead on East Hastings Street into North Burnaby. The purchase of 60-75 articulated trolleys by the end of the century was also planned (BC Transit Planning Department 1992). None of these initiatives came to pass as a new provincial government initiated a turnover in BC Transit senior management and an unpublicised status quo approach to trolley expansion began.
A positive initiative in the early 1990’s was the replacement of the trolley system’s original mercury arc rectifier stations, needed to convert high-voltage alternating current to 600 Volts direct current, with more efficient and less hazardous solid-state rectifier stations. This $12 million programme was completed in 1994 and achieved a nine percent reduction in electricity consumption (n3).
In 1993 the Vancouver Regional Transit Commission responded to a presentation by the public transit advocacy group Transport Action BC by requesting a report from BC Transit on the possible expansion of the trolley system (BC Transit 1993b). While the report identified a number of routes which were candidates for electrification, it concluded that, “the status quo approach appears to be the best strategy.” The transit commission responded by recommending that expansion, “be considered where financially and feasibly possible.” (Truscott 1993) While no further consideration appears to have been given to expanding the trolleybus system, BC Transit has continued to “fine tune” the system by incrementally improving the trolley overhead infrastructure. This work has enabled higher speed operation and reduced dewirements. Most recently, the heavily used overhead at the south end of the Granville Bridge was upgraded in the summer of 1995.
While there are currently no new trolleybuses on order for the system, BC Transit’s Ten-Year Plan anticipates replacing the current fleet between fiscal years 2002 and 2005. However, only 225 replacement vehicles are planned while the current fleet numbers 244. This reduction in fleet size is to be made possible by a reduction in the spare ratio and the reduced demand for trolleys with the introduction of the Broadway-Lougheed light rail transit line and limited stop, diesel “RapidBus” service on the Granville corridor. Even with this reduced fleet size, some service increases on the remaining trolley routes will be possible (BC Transit 1995). Whether there will be enough trolleys to provide needed service expansions on existing trolley routes remains open to question. In the mean time, the City of Vancouver’s Draft Transportation Plan, produced late in 1996, recommends that BC Transit immediately begin the acquisition of new trolleybuses (City of Vancouver 1996). Three possible expansions of trolleybus service are, however, identified in BC Transit’s Ten-Year Plan. These include the electrification of the False Creek South route, the extension of electric trolleybus service into North Burnaby on Hastings Street, and the creation of new route serving the new Pacific Place development on the south-east side of downtown Vancouver (BC Transit 1996). BC Transit’s five-year plan includes a budget of $3.3 million in 1999/2000 for the installation of trolley wires on Pacific Boulevard to meet the last of these expansion plans (BC Transit 1997).
Projections of bus demand in BC Transit’s TransAction 2002 five-year plan (BC Transit 1997) are a cause for concern. The plan includes a base case expansion scenario that suggests the purchase of 175 buses for service expansion; however, none of these would be trolley buses. This is despite the fact that the plan proposes to focus a large portion of new transit resources in markets where transit is an attractive travel alternative, such as the City of Vancouver where trolleybuses currently provide the bulk of the service. The plan instead proposes to reallocate 20 existing trolleybuses from corridors where express and RapidBus services are being developed to remaining trolley routes. Possibly more telling still for the future of the trolleybus system is the more aggressive Transport 2021 scenario given in TransAction 2002. Under this scenario, 480 expansion buses would be purchased by 2002 but none would be trolleybuses. This amounts to a roughly 50% increase in the total bus fleet but with no corresponding increase in the trolleybus fleet.
BC Transit’s Glen Leicester (1993) provides a number of contributing factors for the survival of the Vancouver trolleybus system. These are summarised in the following table:
Table 2 Reasons for the survival of trolley buses in Vancouver (adapted from Leicester 1993)
|Timing||In most cities the decision to eliminate trolleys was taken in the 1960’s. Since a decision was not made in Vancouver until the 1970’s, other factors, such as rising oil prices and a growing environmental awareness, suggested the retention of the trolley system.|
|Geography||The City of Vancouver was almost completely developed when the trolley system was built and is surrounded by water on three sides. This reduced the pressure for incremental route extensions and corresponding expenditures to enlarge the trolley network.|
|Publicly-owned utility||The early “provincialisation” of the system under BC Hydro helped keep trolley buses in a favourable position. Abundant hydroelectric power helped keep electricity costs down.|
|Economies of scale||The large size of the Vancouver trolley system created economies of scale in operation and maintenance which were not available to smaller systems.|
|Topography||While not a major factor in the decision to retain trolleys, the presence of hills on most trolley routes does work to the advantage of trolleybus performance characteristics.|
Trolleybuses operate by drawing power from a pair of overhead wires. The vehicle can deviate about five metres to either side of the centreline of the wires in order to pick up passengers or pass obstructions. Most trolleybus designs are derived from standard diesel bus bodies with the engine, transmission and exhaust system replaced with electrical propulsion equipment (Rafter 1995). The trolley bus produces no direct emissions and so is a true zero emission vehicle; however, indirect emissions are produced if electricity is generated from fossil fuels. The major advantages of trolleybuses are summarised in Table 3.
|Zero-emissions||No direct emissions and, except with fossil fuel power generation, trolleybuses produce no indirect emissions.|
|Lower noise levels||Generally no louder than ambient street noise. Electric braking greatly reduces the use of friction braking and accompanying squeal.|
|Efficiency||No energy is wasted keeping an engine idling when it is not required. Up to 30 percent of braking energy can be returned to the overhead for use by other vehicles using regenerative braking (Vuchic 1981).|
|Performance||Trolleybuses have excellent acceleration (n4) and do not suffer the level of performance deterioration on hills and with passenger loads that diesel and natural gas buses experience.|
|Lower maintenance||Diesel and natural gas buses require a major engine overhaul every five to six years, trolleys do not require such major scheduled maintenance. Trolleybuses use direct drive and so do not require a maintenance-intensive mechanical transmission. By using dynamic (electric) braking trolleys require much less use of friction brakes and so have lower brake maintenance costs.|
|Longer vehicle life||BC Transit assumes trolleybuses to have a 30 year life, relative to a 20 year life for a diesel bus.|
|Proven technology||The basic concepts of trolleybuses have been in use for about 70 years compared to the much more recent development of natural gas and fuel cell buses.|
|Low power costs||BC Transit has found the combined costs of electricity and overhead wire maintenance for trolleys to be lower than the cost of diesel fuel for diesel buses on a per kilometre basis (see Table 5).|
|Rider preference||Some evidence indicates that transit passengers prefer trolleybuses to diesel buses.|
Trolleybuses also feature a number of disadvantages relative to diesel, and in many cases, natural gas, buses. These are given in Table 4.
|High capital costs||Trolleybuses cost 1.5 times those of a diesel bus. The overhead current distribution infrastructure is a high cost item.|
|Inflexibility||Routings are limited by overhead wire coverage and configuration (n5).|
|Power failures||Outages in power supply can bring the system to a halt (n6).|
|Intersections||Where trolley lines cross or join, buses must slow to prevent dewirement and possible overhead damage.|
Some trolleybus characteristics are less clearly defined as advantages or disadvantages. For example, the need to slow for crossings, switches and some curves slows the vehicle in intersections where pedestrians may be present and helps prevent passengers from experiencing unpleasant lateral acceleration as a bus turns or rounds a curve. Likewise, the overhead trolley wiring, seen by some as “visual pollution”, also acts as a standing advertisement that there is (usually) frequent transit service on the street (Vuchic 1981). Increasing sensitivity to aesthetic concerns has led to attempts at reducing the visual impact of the trolley overhead system. An example can be seen on University Boulevard where the trolley overhead and its supporting poles and arms has been designed to blend as much as possible with the existing roadside trees (BC Transit 1993b).
The cost issue is one that is not clearly decisive. The cost of the fixed trolleybus infrastructure in Vancouver has already been absorbed with the well maintained overhead system being valued at $100 million and the recently completed replacement of rectifier stations having cost $15 million (Mortensen 1996). The latter investment is expected to last 35-40 years while the continuing maintenance cost for the overhead system is reflected in operating costs. In 1987 BC Transit compared trolleybus and diesel bus operation and maintenance costs with the results given in Table 5.
|Revenue service hours||
|Revenue service kilometres||
|Average speed (km/h)||
|Variable maintenance cost/km||
|Variable fuel (power) cost/km||
|Trolley overhead cost/km||
While the total cost per kilometre of service is higher for trolleys, a number of qualifying factors must be considered. Firstly, is cost per service kilometre the appropriate measure to use given that the average diesel speed is over 50 percent greater than the average trolley speed? A purely distance based comparison does not seem fair since trolleybuses are operated on the busiest city routes where stop-and-go traffic, frequent passenger stops and high passenger loadings place more stress on vehicle components such as doors and propulsion systems than would be the case on most diesel routes operating under less adverse circumstances. Basing comparisons on cost per service hour reverses the ranking with trolley costs of $17 an hour being substantially below diesel costs of just over $22 an hour. Neither measure would seem to serve the purpose by itself since one is biased towards operating speed and the other to service hours. The age of the data (1987) must also be considered since a number of upgrades to increase the reliability of the trolley fleet have been undertaken since then and the resulting potential reduction of maintenance costs has not been publicly quantified.
While there was never a vote in Vancouver to determine what transit mode would replace the B.C. Electric’s streetcar system, such a vote did take place in the small and hilly interior city of Nelson. In 1946 Residents of Nelson voted 43% in favour of replacing the streetcars in their city with trolleybuses (n7). While only 4% of voters supported the purchase of gas buses, this was the route taken by city council (Parker 1992). Similarly, a demonstration of a Seattle trolleybus in Victoria in 1946 proved very popular but gas buses were selected to replace the streetcars, although no vote was held (Ewert 1992).
A 1990 survey in Vancouver found 62 percent of city residents agreed with the statement that “trolleybuses are better than diesel buses” (BC Transit 1993b). Some recent events in Vancouver also indicate a continuing public preference for trolleybuses. A 1993 decision by BC Transit to operate diesel buses on the 19 Stanley Park route raised considerable local opposition (Strachan 1993). In 1994 the City of Vancouver passed a motion “that BC Transit be requested to use electrified trolleys, as much as possible, on West End routes.” (City of Vancouver 1994) While the Stanley Park situation remains unresolved, BC Transit did resume Sunday operation of trolleybuses on the Davie and Robson routes in the West End in June 1995 only to return them to diesel operation about a year later.
Evidence of increased ridership with trolleybuses compared to diesel buses on the same route is limited but some rough estimates have been produced by transit agencies in San Francisco and Seattle. The San Francisco Municipal Railway realised 10 to 18 percent ridership increases with conversion to electric operation and 10 to 15 percent decreases when diesel buses were temporarily substituted on trolley routes. Seattle Metro reports a ridership increase of approximately 10 percent when converting diesel bus routes to trolleys (Freeman 1993).
While natural gas buses do not fit BC Transit’s stated criteria for trolley replacements of being emission free and quiet, it is possible they could be given some consideration. Certainly the emission-free aspect is suggested by the misleading “Clean Air Bus” slogans emblazoned on BC Transit’s current fleet of 25 CNG buses.
CNG buses are substantially more polluting than trolleys, even when emissions from the fossil fuel generation of electricity are taken into consideration. A study done for the aborted Los Angeles trolleybus project (quoted in Rafter 1995) found that CNG buses emitted five times the nitrogen oxides and 20 percent more particulate matter than trolleybuses, based on a share of fossil fuel electrical generation. Clearly, in British Columbia where the vast majority of electricity is generated by hydroelectric means (n8), the comparison would be even less favourable to the CNG bus. It should also be considered that natural gas supplies are limited and so do not represent a renewable form of energy as does hydroelectricity. While gas supplies would no doubt outlive an initial order of CNG buses, removing the trolleybus infrastructure, as implied by a decision to go with CNG, would make returning to the trolleybuses powered by renewable energy very expensive.
Another disadvantage of CNG buses is the 1,500 pound (c. 700 kg) weight penalty relative to a diesel bus. Not only does this additional weight risk making the bus overweight and so force a reduction in capacity, moving this additional mass requires more energy (Bus World, Spring 1995, p. 10).
BC Transit and the provincial government have given hydrogen powered fuel cells a high profile as a transit power source of the future by providing funding for research into fuel cells being conducted by Ballard Power Systems of North Vancouver, an industry leader in the development of fuel cells for stationary and mobile applications (BC Transit 1993a). Ballard’s fuel cell uses a polymer membrane and platinum catalyst to produce electrical current without combustion from the reaction of hydrogen and oxygen (Williams 1994). By stacking many fuel cells together, enough current and voltage generation capacity can be created to power a vehicle. Fuel cell buses would appear to offer many of the advantages of trolleybuses (low noise, smooth ride, etc.) without the limitations and costs imposed by the need for an overhead contact system. However, despite the promise of the technology, a number of major issues have yet to be resolved.
One of these issues is the source of the hydrogen fuel. Hydrogen gas is currently produced from steam reformation of natural gas. Long range hopes focus on the electrolysis of water using electricity generated from solar or wind power, or another environmentally-friendly source. Hydrogen can also be produced off the vehicle although off-vehicle production being favoured for transit uses since this reduces the equipment which must be carried on the vehicle. The difficulties of handling a gaseous fuel are mitigated by the large scale and central fuelling facilities used for transit vehicles. The favoured method for on-vehicle hydrogen production is reformation from methanol using steam and a catalyst (Williams 1994). On-vehicle reformation, however, tarnishes the fuel cell promoters’ much-touted claim to having a “zero-emission fuel” since carbon dioxide, strongly implicated in global warming, is produced as a by-product. Long-term hopes are to produce hydrogen or methanol from biomass, with substantial reductions in carbon dioxide emissions relative to other forms of synthesis. As shown in Figure 1, existing synthesis methods are very closely comparable to using diesel fuel in terms of overall energy efficiency and produce just over three-quarters of the carbon dioxide a diesel fuelled vehicle would produce (Daimler-Benz 1994). Comparisons in the literature with electrically powered vehicles, such as trolleybuses, are generally not applicable in British Columbia since most studies assume electricity is generated from thermal sources, not from emission-free hydroelectricity.
Performance of fuel cell vehicles is also an issue. Range, power, weight, energy efficiency and performance are all closely related. Adding range and power with larger fuel tanks and fuel cell stacks adds weight and decreases efficiency. This is especially true for vehicles where hydrogen gas is stored on the vehicle, although improvements in storage tanks are reducing the weight penalty of large fuel tanks (Williams 1994). Ballard estimates a realistic power to weight ratio for high-density fuel cell stacks as being in the range of 500 to 1000 W/kg (Prater 1994). This gives a weight range of 205 to 410 kg for the 205 kW fuel cell engine in Ballard’s prototype 40′ low-floor transit bus (n9). When Ballard begins commercial production in 1998 they hope to achieve a range of 560 km for a 75 passenger low-floor bus (Ballard 1995b).
The capital and operating costs of the fuel cell bus remain unclear. Ballard expects that their initial vehicles will be less costly than trolleybuses (estimated to cost $550,000 to $600,000 in 1994, excluding trolley infrastructure costs) while production vehicles will be priced competitively with compressed natural gas buses, at around $300,000 1994 dollars (Electric Vehicle News 1994). However, the realism of these figures needs to be questioned since the Ballard bus uses almost all of the same components, such as electronic propulsion controls and an electric traction motor, used on a trolleybus (n10). Most simply, the Ballard bus substitutes fuel cells for trolley poles with other components remaining more or less the same. If Ballard can achieve these cost economies for fuel cell buses, a substantial drop in trolleybus costs could reasonably be anticipated.
Hydrogen costs for fuel cell buses are currently exceptionally high at 62 cents per kilometre, although Ballard maintains that this could drop to 21 cents, slightly higher than the 15 to 18 cent cost of fuelling a standard city bus (Nichols 1995). Information on how fuel costs can be reduced is lacking but examining Ballard’s long-term hopes of generating hydrogen from the electrolysis of water is informative. Hydrogen advocates claim that the cost of electricity generated using solar power will decline ten-fold, making it half the price of electricity generated from coal and nuclear plants (Golob and Brus 1993). If electricity costs are to decline so dramatically, the efficiency of the fuel cycle should be examined to determine if the cost of supplying electricity directly to the vehicle would be less than the cost of conversion of electricity to hydrogen and back to electricity. The following table shows the efficiency of this process:
Table 6 Efficiency of hydrolysis/fuel cell energy transformations (n11) (sources: Goleb and Brus 1993, Ballard 1995a)
|Step (energy converted)||Step efficiency||Cumulative Efficiency|
|Hydrolysis (electrical to chemical)||60%||60%|
|Fuel cell (chemical to electrical)||50%||30%|
Given that the hydrolysis/fuel cell energy conversion process is only 30% efficient, adequate consideration must be given to electric vehicles which are supplied directly with electric current and so are not subject to this major waste of energy. This is especially true in Vancouver where an extensive current distribution system for trolleybuses is already in place. The unresolved costs of fuel cell buses, plus the inherent inefficiency of what is hoped to be the long-term source of hydrogen for fuel cells, suggests that a cautious approach be taken and that decisions about replacing the existing, proven trolleybus technology not be made until the potential replacement technologies have reached a mature stage of development.
A three-year demonstration of fuel cell bus technology with the Chicago Transit Authority and a test with BC Transit, expected to start in January and April 1997 respectively, should help resolve some of the outstanding questions about the viability of fuel cells for transit use (Bus World 1995, Pynn 1996). If these tests are successful, fuel cell buses may provide an alternative to diesel and natural gas buses in areas where noise and air quality concerns are important. In cities with existing trolleybus networks, such as Vancouver, retaining trolleybuses and replacing diesel and natural gas buses with fuel cell buses would appear to make the most sense environmentally.
With BC Transit projecting to make a decision on the future of the trolleybus system sometime between 2000 and 2002, an analysis of the alternative technologies currently available suggests that a new fleet of trolleybuses will be purchased if BC Transit keeps its promise to consider only quiet, pollution-free vehicles. CNG buses, while somewhat cleaner than diesel buses, are neither quiet nor pollution free. The heavily touted Ballard fuel cell bus fulfils the noise and environmental requirements but may not be a mature technology by the year 2000 since trials in regular transit service are not expected to begin until early 1997. Costs for the Ballard fuel cell bus have also yet to be resolved and it appears extremely unlikely that capital and operating costs for the Ballard bus will fall below those for electric trolleybuses.
Given recent investment and continuing high maintenance standards in the trolleybus power distribution network, there is little cause for concern that a major fixed infrastructure investment must accompany the purchase of new trolleybuses. It appears that the purchase of new trolleybuses is the most economical and environmentally sound choice, especially for a city like Vancouver where the bulk of electricity generation is from zero-emission, renewable hydroelectric sources. The short-comings of trolleybuses, notably the lack of route flexibility and the visual impact of the overhead, have been accepted for almost 50 years in Vancouver and are clearly not insurmountable. Other technologies have yet to achieve the advantages of the trolleybus at a competitive cost. Barring a major technological breakthrough, the renewal of the Vancouver trolleybus fleet appears the best option with fuel cell buses best being used to replace diesel and natural gas buses once the technology has been proven.
- Boston, Dayton, Philadelphia, San Francisco and Seattle.
- 244 of these vehicles remain, one was accidentally destroyed by fire during a labour dispute in 1984 as a result of a now corrected design flaw.
- Based on a letter dated March 27, 1996 from Arthur Yuen, Manager, Trolley Overhead Department, BC Transit.
- BC Transit has programmed its Vancouver trolley fleet for a slower acceleration rate than the vehicles are capable of. Acceleration on trolleybuses operated in other cities is noticeably better.
- However, note that the Vancouver overhead system has many possible routings not used in regular service.
- However, note that the Vancouver overhead network is dense and provides some redundancy by allowing operation on parallel streets served by different circuits and/or substations. This is especially true in the important downtown area.
- The results of the voting were as follows: Purchase trolleybuses (43%), purchase new streetcars (30%), repair existing streetcars (13%), leave decision to council (10%), and lastly, purchase gas buses (4%).
- In the year ending March 31, 1995, BC Hydro generated 7.5 percent of its electricity from Burrard Thermal, its only thermal generating facility. Burrard Thermal began operation in 1962, 14 years after trolleybuses were introduced in Vancouver. 14.4 percent of the remaining production came from purchases and transactions (generating sources unknown), leaving 78.1 percent of generation from domestic hydroelectric sources (BC Hydro 1995).
- Ballard’s brochure (Ballard 1995a) on the fuel cell bus engine does not provide a weight for the engine, thus necessitating this rather vague estimate.
- The voltage generated by Ballard’s fuel cells, 650 to 750 Vdc, (Ballard 1995a) is closely comparable to the standard trolleybus current supply voltages of 600 and 750 V. This would suggest that components for one mode would be applicable to the other with little modification.
- The fuel cell efficiency used here is the average of the idle (60%) and full power (40%) efficiencies given in Ballard 1995a. The efficiency of converting electrical to mechanical energy (motion) is not included since similar energy losses would occur in a trolleybus. Ballard (1995a) estimates this efficiency at 92 percent.
American Public Transit Association (APTA), 1992, Electric Trolley Bus, (Washington: American Public Transit Association).
BC Hydro, 1976, Broadway 9 Alma-Brentwood Crosstown Bus Service (schedule effective 14 May to 22 July, 1976) (Vancouver: BC Hydro).
BC Hydro, 1995, Making the Connection: The B.C. Hydro Electric System and How it is Operated (Vancouver: BC Hydro).
BC Transit, 1993a, Annual Report 1992-1993 (Vancouver: BC Transit)
BC Transit, 1993b, Electric Trolley Bus Report (Vancouver: BC Transit).
BC Transit, 1995, Vancouver Region 10 Year Bus Fleet Plan 1995-2006, Draft 2 (Surrey:BC Transit).
BC Transit, 1996 (? – report is undated), Vancouver Region 10-Year Bus Development Plan, Final Draft (Surrey:BC Transit).
BC Transit, 1997, TransAction 2002: Service Plan and Funding Strategy (Surrey:BC Transit).
BC Transit Planning Department, 1992, “Trolley Bus Operation in Vancouver”, Electric Lines, 5:2 (March-April 1992) p. 32-38.
Ballard, 1995a, Zero-Emission Fuel Cell Engine (North Vancouver: Ballard Power Systems).
Ballard, 1995b, Zero-Emission Fuel Cell Bus Engine Implementation Plan (North Vancouver: Ballard Power Systems).
Bus World, 1995, “Chicago to test Ballard fuel cell buses”, Bus World, 18:2 (Winter 1995-96), p. 8.
City of Vancouver, 1994, Bus Service in the City of Vancouver – Service Design Guidelines, Safety, Routes (City of Vancouver: Vancouver).
City of Vancouver, 1996, Draft Transportation Plan (City of Vancouver: Vancouver).
Daimler-Benz, 1994, “Fuel Cells Hit the Road”, Daimler-Benz HighTechReport, 3/1994, p. 13-21.
Electric Vehicle News, 1994, “Ballard Predicts Fuel Cell Transit Buses for 1998”, Electric Vehicle News, April 1994, p. 1, 4-5.
Ewert, Henry, 1986, The Story of the B.C. Electric Railway Company (North Vancouver: Whitecap).
Ewert, Henry, 1992, Victoria’s Streetcar Era (Victoria: Sono Nis Press).
Freeman, Luther, 1993, “Sacramento Trolley Bus Starter System: An Investment in Clean Air”, Transit California, March 1993 p. 6-11.
Golob, Richard and Eric Brus, 1993, The Almanac of Renewable Energy (New York: Henry Holt and Co.)
Kelly, Brian and Daniel Francis, 1990, Transit in British Columbia (Madeira Park, BC: Harbour).
Leicester, Glen, 1993, Trolley Buses in Vancouver – Overview (Vancouver, BC Transit).
Leicester, Glen, 1996, “Trolley buses not at their end yet” (letters), The Kitsilano News, March 27, 1996, p. 11.
Mortensen, Klaus, 1996, Conversation with Klaus Mortensen, BC Transit Rectifier Station Supervisor, March 12, 1996.
Nichols, Mark, 1995, “The magic bus”, Maclean’s December 25, 1995/January 1, 1996, p. 52.
Parker, Douglas V., 1992, Streetcars in the Kootenays (Edmonton: Havelock House).
Prater, Keith B., 1994, “Polymer electrolyte fuel cells: a review of recent developments”, Journal of Power Sources, v51, p. 129-144.
Province, 1992, “More trolleys on tap”, The Province, February 24, 1992.
Pynn, Larry, 1996, “Pollution-free bus project gets $8.6 million from province”, The Vancouver Sun, March 27, 1996, p. B4.
Rafter, David O., 1995, “The Electric Trolley Bus: A Neglected Mode in U.S. Transit Planning” Journal of the American Planning Association, 61:1 (Winter 1995) p. 57-64.
Schaefer, K.D., 1996, Conversation with Karl Schaefer, BC Transit Trolley Coach Foreman, March 12, 1996.
Strachan, Alex, 1993, “Switch to diesel buses leaves West End residents fuming” The Vancouver Sun, December 6, 1993, p. B2.
Truscott, Brian, 1993, “Transit commission stands behind costly trolleys” The Vancouver Courier, September 12, 1993, p. 4.
Vuchic, Vukan R., 1981, Urban public transportation, (Englewood Cliffs, NJ: Prentice-Hall).
Williams, Robert H., 1994, “The Clean Machine”, Technology Review, April 1994, p. 20-30.