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39 CHAPTER FOUR HIGHER CAPACITY BUS TECHNOLOGIES MANUFACTURERS OF HIGHER CAPACITY To examine three of the performance measures in more BUSES AND BUSES OFFERED detail, recent reports from 2001 to 2005 of the ABTC were reviewed for all three types of HC buses and for 40-ft buses. The databases of APTA and CUTA were examined to iden- Six reports on articulated buses, one on double-deck buses, tify which bus manufacturers made the HC buses used by four on 45-ft buses, and six on 40-ft buses were reviewed. the 68 transit agencies. The results of that effort identified The performance measures of acceleration, grade climbing, 16 manufacturers. Over the years, there have been changes in and fuel economy were examined and the results are given in the corporate structures, ownership of bus manufacturers, Table 35. and brand names. Some manufacturers have left the North American market, although 6 of these 16 continue to market The Altoona data support the perceptions reported by tran- HC buses. Additional potential bus manufacturers were iden- sit agencies of the performance of their diesel-powered articu- tified from APTA and CUTA membership directories and a lated and/or 45-ft buses on both acceleration and gradability review of trade magazines that feature information on mo- measures. Both the articulated and the double-deck buses tested torbus transportation. At the time of this report, eight bus were slower compared with the 40-ft buses tested. This is an ex- manufacturers were identified as currently marketing HC pected result because the four articulated buses were approxi- buses in North America to either the public or private trans- mately 50% heavier than the 40-ft buses tested. Information on portation sectors. These eight manufacturers, along with the the installed horsepower was not provided. However, based on type of HC buses being marketed, are provided in Table 32. the engine model information provided, it is estimated that the installed horsepower for the articulated and double-deck buses The bus manufacturers' questionnaire (see Appendix A) tested was about 20% to 25% higher than for the 40-ft buses. was sent to the eight identified HC bus manufacturers. Re- The acceleration of the 45-ft intercity coaches was better com- sponses were received from seven manufacturers. The inter- pared with the 40-ft buses tested. est, type, and cost range information that was provided in the responses is presented in Table 32. Tables 33 and 34 contain The Altoona data also support the reported performance technical descriptions of the HC models that the responding relative to fuel economy for articulated and double-deck bus manufacturers reported to be marketing to North Ameri- buses; that is, 30% to 35% poorer fuel economy overall when can transit agencies compared with 40-ft buses. The reported same or better per- formance on fuel economy of their 45-ft buses is most likely OPERATING PERFORMANCE OF CURRENT attributed to the type of service (express and/or commuter) HIGHER CAPACITY BUSES because the ABTC-measured overall fuel economy was 26% poorer than that of the 40-ft buses. From the transit agency survey responses, several HC bus performance issues were reported. In the following sections, An emerging technology for transit buses is the use of hy- test data on acceleration, fuel economy, and noise perfor- brid propulsion systems, which result in significant improve- mance of HC buses are presented to provide some quantifi- ments in acceleration and fuel economy. The available cation with respect to these performance areas. Altoona test reports for buses using hybrid technology were examined for the effects on bus performance. Table 36 con- Acceleration and Fuel Economy tains the acceleration, gradability, and fuel economy data for of Higher Capacity Buses an articulated bus equipped with hybrid propulsion technol- ogy compared with five articulated buses, four equipped with The survey asked respondents about their operating experi- diesel engines and one with a CNG engine. The perfor- ences with HC buses. The intent of the related survey question mances of the diesel and CNG buses were averaged for all was to gather information on how transit agencies perceived tests except the fuel economy test, which is the average of the the performance of their HC vehicles compared with their four diesel buses. standard 40-ft buses for several performance measures. The transit agency responses to the survey question were presented The data in Table 36 illustrate the potential for hybrid tech- in chapter two for each of the three types of HC vehicle. nology in overcoming two of the common concerns of using

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TABLE 32 LIST OF POTENTIAL SUPPLIERS OF HIGHER CAPACITY BUSES AS OF JANUARY 2007 Max. Unit Cost Altoona Meets Meets Canada Possible Model HC Vehicle Pass. (U.S. dollars in Market Tests Buy Motor Vehicle HC Bus Manufacturers ID Type Seatsa thousands) US/Canada Completed America Regulations Alexander Dennis E500 Double-deck 81 600 U.S. & Can yes no yes DamilerChrysler Comm. Buses NA S 417 45-ft coach 58 450 U.S. & Can no no yes Motor Coach Industries D 4500 45-ft coach 57 450 to 500 U.S. & Can yes yes yes New Flyer D60LF Articulated 64 550 to 675 U.S. & Can yes yes yes DE60LFb Articulated--Hybrid 64 755 to 1,000 U.S. & Can yes yes yes DE60LFRb Articulated--Hybrid 64 760 to 1,000 U.S. & Can yes yes yes DE60LFAb Articulated--Hybrid 64 765 to 1,000 U.S. & Can yes yes yes North American Bus Industries Exp. 4500 45-ft coach 54 inp U.S. yes yes inp 436c Articulated 65 500 to 700 U.S. yes yes unknown 60-LFWc Articulated 61 500 to 700 U.S. yes yes unknown 60-BRTc Articulated BRT 58 650 to 850 U.S. yes yes unknown 65-BRTc Articulated BRT 67 700 to 900 U.S. no yes unknown Nova Bus Nova LFS Articulated inp inp Can no no yes Prevost Car X3-45 45-ft Coach inp inp U.S. & Can no no yes Van Hool AG300 Articulated 43 Mid 400s U.S. & Can no no yes AGG300 Double Articulated 61 Low 600s U.S. no no inp C2045 P&R 45-ft Coach 57 TBD U.S. no no inp Sources: HC Bus Manufacturers S urvey responses and References 22 and 23. a Actual number of seats depends on customer specifications. b The "R" identifies a Restyle model, an "A" identifies an advanced style BRT model, and no letter after LF identifies a traditional model. c The "LFW" identifies a low-floor model, the "C" identifies a composite model, the "BRT" identifies a BRT model, and "436" identifies a standard floor model. inp = Information was not provided or available in literature; TBD = to be determined.

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41 TABLE 33 TECHNICAL DESCRIPTION OF HIGH CAPACITY BUSES (Articulated models) Model Identification Model Identification (BRT)a Technical Description NF NFb NABI NABI VH NF NABI NABI D60LF DE60LF (R) 436 60LFW AG300 DE60LFA 60 BRT 65 BRT Length, Not Including Bumpers (ft) 60.7 61.7 59 60 59.75 62.7 60 65 Width, Not Including Mirrors (in.) 102 102 102 102 102 102 102 102 Height (in.) 121 132 118 116 134 136 137 137 Approach Angle (deg) 9.01 9.01 9 9 9 8.5 9 9 Departure Angle (deg) 8.76 8.76 9 9 9 8.76 9 9 Breakover Angle (deg) 8.35 8.35 11/11 9/10.5 inp 8.35 8.7/10.2 8.7/8.1 Turning Radius, Outside (ft) 38.8 38.6 44 44 39.3 38.6 44 46 No. of Passenger Doors 2,3 2,3 2,3 2,3 3,4 3,4,5 2,3 2,3 Option for Passenger Doors on Left Side no yes no no inp yes yes yes Entrance/Exit Height at Doors (in.) 16 16 15 15 14.2 16 15 15 No. Steps to Enter/Exit 1 1 3 1 1 1 1 1 Wheelchair Equipment (lift or ramp) R R L R R R R R Lift/Ramp Door Locations all all 1 1 2 all 1 1 Maximum Number of Seats 64 64 65 61 43 64 58 67 Maximum Number of Standees 57 53 inp inp 57 53 inp inp Gross Vehicle Weight Rating (lb) 63,880b 63,880 66,000 66,000 inp 68,000 66,000 66,000 Propulsion Optionsc D, N D, N, H D, N, H D, N, H D&F D, N, H D, N, H D, N, H Powered Axle (two or three) 3 3 3 3 2 3 3 3 Source: Manufacturer survey responses and Reference 24. a BRT models have body streamlining features. b Both the DE60LF and the DE60LFR were reported to have the same technical description information. c Propulsion codes: D = diesel, N = natural gas, H = hybrid (either diesel or gasoline), and F = fuel cell. Manufacturer codes: NF = New Flyer, NABI = North American Bus Industries, NB = Nova Bus, VH = Van Hool. inp = Information was not provided or available in literature TABLE 34 TECHNICAL DESCRIPTION OF HIGHER CAPACITY BUSES (Double-deck and 45-ft models) Double-Deck Models 45-ft Models Technical Description AD AD AD DC MCI NABI VH E500 E500i 42' E500H S417 D4500 Exp 4500 C2045 Length, Not Including Bumpers (ft) 40 42 42 45 45 45 45 Width, Not Including Mirrors (in.) 102 102 102 102 102 102 102 Height (in.) 168 168 168 144 138 143 138 Approach Angle (deg) 8 8 8 inp 9.8 9 inp Departure Angle (deg) 9 8 8 inp 8.3 10 inp Breakover Angle (deg) 8 7 7 inp 5a 8 inp Turning Radius, Outside (ft) 39 41 41 40 47 43 40.3 No. of Passenger Doors 2 2 2 1 1 1 1 Option for Passenger Doors on Left Side no no no no no no no Entrance/Exit Height at Doors (in.) 13.4/12.5b inp inp 6c 15.6b 16b inp No. Steps to Enter/Exit 1 1 1 6 4b 4 inp Wheelchair Equipment (lift or ramp) R R R L L L L Lift/Ramp Door Locations 2 2 2 rear center rear center/rear Maximum Number of Seats 81 89 79 58 57 5357d 5765d Maximum Number of Standees 10 2 15 0 a inp inp Gross Vehicle Weight Rating (lb) 52,000 52,000 52,000 50,516 48,000 52,000 50,700 Propulsion Optionse D D H D D, H D D Source: Manufacturer survey responses and References 25 and 26. a Respondent stated that standees vary by state regulations. b Information obtained from Altoona test reports for model. c Kneeled. d Number varied depending on seating selected. e Propulsion codes: D = diesel, N = natural gas, H = hybrid (either diesel or gasoline), and F = fuel cell. Manufacturer codes: AD = Alexander Dennis; DC = DaimlerChrysler Commercial Buses, NA; MCI = Motor Coach Industries, NABI = North American Bus Industries, VH = Van Hool. inp. = information not provided.

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42 TABLE 35 TESTING RESULTS OF HC BUSES COMPARED WITH 40-FT BUSES (All buses--Diesel propulsion) Average Times to Reach Test Speeds, in seconds (percent difference of time--HC bus compared with 40-ft bus) Test Speeds 45-ft (mph) Articulated Double-Deck Inter-City Coach 40-ft 10 4.7 6.2 4.0 5.0 (-6%) (24%) (20%) 20 9.1 10.4 7.4 8.7 (5%) (20%) (8%) 30 14.8 16.4 11.6 13.3 (11%) (23%) (13%) 40 24.7 25.8 17.6 21.0 (18%) (23%) (11%) 50 43.3 43.6 27.1 33.2 (30%) (31%) (18%) Average Calculated Sustainable Grade at Test Speeds, in percent (percent difference of sustainable grade--HC bus compared with 40-ft bus) 10 10.8 9.2 13.0 11.2 (4%) (18%) (16%) 40 3.9 3.8 6.5 5.3 (23%) (28%) (23%) Test Cyclea Average Fuel Economy for Test Cycle, in mpg (percent difference of mpg--HC bus compared with 40-ft bus) CBD 2.4 2.3 2.5 3.5 (31%) (34%) (28%) Arterial 2.9 2.6 3.0 4.1 (29%) (36%) (27%) Commuter 5.3 4.6 5.9 7.3 (27%) (37%) (19%) Overall 3.0 2.8 3.2 4.3 (30%) (35%) (26%) Source: References 2427. a Reference 28, Section 5.12(20) Design Operating Profile. articulated buses, namely acceleration capability and fuel Most certainly, the hybrid articulated bus that was tested had economy. All tests were conducted at seated load weight. The the capability of operating all day. hybrid articulated bus test weight was 49,880 lb. The average seated load weight of the five diesel/CNG articulated buses Operating Performance Comparison was 51,288 lb. Although the hybrid articulated bus was lighter of King County Metro Transit Fleets by approximately 3% (1,400 lb), which undoubtedly helped its performance, buses equipped with hybrid technology Over the years, Metro Transit has tested its different motor could provide significant improvement in acceleration and bus fleets for acceleration and grade climbing capability. Of fuel economy performance compared with similar buses particular interest in recent tests was evaluating the capabil- equipped with conventional internal combustion engines. ity of its new hybrid articulated buses. In Table 37, the times to reach various speeds for various grades are presented for Another comment received was that the articulated buses the articulated and 40-ft fleets. All buses were tested at 130% could not operate all day on a single tank of fuel. The hybrid of seated load weight, with the air-conditioning system off. articulated was equipped with a 167-gallon fuel tank. That The test grades are typical of Metro Transit's hilly routes. size tank would provide a range capability of 718 miles, The test weight of the bus is also given in this table. assuming the bus was operating on the Design Operating Profile test cycle. The four diesel articulated buses were The Metro Transit test results clearly show the improve- equipped with fuel tanks with capacity of from 120 to 140 gal- ment in performance with the hybrid technology. The lons. The calculated ranges would be 360 to 420 miles, again dieselelectric hybrid articulated bus was the only articulated assuming that the buses were operating on the Design Oper- sub-fleet that met all of Metro Transit's performance specifi- ating Profile test cycle. The lowest fuel economy for the test cations. On a level road the dieselelectric hybrid was nearly buses was 2.2 mpg (Central Business District cycle) for a bus as quick as the much lighter weight 40-ft bus, which should equipped with a 140-gallon fuel tank, which results in a com- facilitate interchangeability when assigning buses to routes. puted maximum range of 308 miles. The fuel economy data appear to indicate that articulated buses should be able to op- The articulated buses of the 2800 fleet are identical to the erate all day without requiring refueling in most situations. buses in the 2600 fleet (hybrid) except for the propulsion

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43 TABLE 36 ALTOONA BUS TESTING RESULTS: DIESEL VERSUS HYBRID PROPULSION TECHNOLOGY Test Results Diesel/CNG Hybrid Hybrid Articulated Compared with Test Speeds Calculated Times to Speeds Diesel/CNG Articulated (mph) (in seconds) (in percent difference) 10 4.0 3.8 5% better 20 9.1 8.6 5% better 30 15.9 14.7 8% better 40 25.9 23.1 11% better 50 42.3 35.2 17% better Calculated Sustainable Grade at Test Speed 10 10.8% 10.8% same 40 3.7% 4.6% 24 % better Calculated Acceleration, (in ft/s/s) 1 4.1 4.1 same 5 3.7 3.8 3% better 10 3.3 3.5 6% better 15 2.9 3.1 7% better 20 2.5 2.7 9% better Fuel Economy for Test Cycle (in mpga) Test Cycleb CBD 2.4 3.7 54% better Arterial 2.9 4.2 45% better Commuter 5.3 6.6 25% better Overall 3.0 4.4 47% better Source: References 24 and 27. a Fuel economy data are the average of four diesel articulated buses. b Reference 28, Section 5.12(20) Design Operating Profile. technology. When comparing the test performance between Highest Maintainable Speed on 5% Grade Test-- hybrid these two fleets, the improvement with the hybrid technology is 1% better. is as follows: To make use of the low emissions of hybrid technology, 020 Level Road Test--hybrid is 13% better. the hybrid articulated buses will replace the dual-propulsion 045 Level Road Test--hybrid is 15% better. articulated buses that were used for routes servicing the 020 5% Grade Test--hybrid is 17% better. downtown tunnel. In the tunnel, the hybrid articulated buses 010 9% Grade Test--hybrid is 6% better. are operated using a special computer program that limits TABLE 37 PERFORMANCE TEST COMPARISONS OF KING COUNTY METRO TRANSIT FLEETS Articulated Buses Diesel Metro Test 40-ft Diesel HF DM Diesel LF Hybrid LF Spec. Metro Fleet Identification 3200 2300 5000 2800 2600 Test Weight (lb) 39,050 56,560 65,550 56,118 57,753 130% SLW Passenger Seats 42 64 58 58 58 020 mph--Level Road (sec) 7.91 9.74 9.84 9.09 7.94 9 045 mph--Level Road (sec) 30.61 38.32 46.28 40.12 34.10 36 020 mph--5% Grade (sec) 11.86 21.65 18.13 15.76 13.05 14 010 mph--9% Grade (sec) 5.39 6.32 7.83 6.43 6.02 9 Highest Maintainable Speed on 5% Pass Pass N/A 43.4 43.1 43 Grade (mph) Notes: SLW = seated load weight, mph = miles per hour, HF = high floor, LF = low floor, DM = dual mode, N/A = not available. Source: King County Metro Transit.