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Battery Electric Buses—State of the Practice (2018)

Chapter: Chapter 6 - Case Examples

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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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Suggested Citation:"Chapter 6 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2018. Battery Electric Buses—State of the Practice. Washington, DC: The National Academies Press. doi: 10.17226/25061.
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61 Antelope Valley Transit Authority AVTA provides transit service for the cities of Palmdale, Lancaster, and Northern Los Angeles County. AVTA deployed two 40′ BYD electric buses onto Route 1 in November of 2014 using a local grant from the Los Angeles County Board of Supervisors. The agency plans to fully convert its fleet to BEBs by 2018, becoming “fully green by 2018” with a total of 89 BEBs supported by 89 plug-in depot chargers and 13 on-route inductive (also known as wireless) chargers (“Elec- tric Bus Fleet Conversion” 2017). The full fleet conversion will be funded using a $24.4 million CalSTA grant plus another $15 million of AVTA and federal formula funds. The agency expects to begin with the introduction of its first five articulated BEBs. The expansion will continue with receipt of one additional articulated bus every week until reaching a total of five buses. Ultimately, the agency’s goal is to acquire 13 articulated, 30 commuter, and 34 40-foot all- electric buses. The articulated and 40-foot all-electric buses will both utilize the on-route wireless charging infrastructure. AVTA’s Experience Table 12 presents the dashboard information of the AVTA BEB fleet, as well as climate consid- erations on Table 13 during BEB deployment in 2014. The two buses (shown on Figure 33) are supported by two on-route 50 kW WAVE inductive chargers (locations shown on Figure 34) in addition to the bus-OEM supplied plug-in depot chargers. The buses use the wireless chargers for opportunity charging during layovers and the plug-in chargers to top off the buses overnight. Inductive on-route charging relies on a charging architecture that transmits power wirelessly through inductively coupled electromagnetic circuits. A typical installation uses a coil buried in the roadway. An initial challenge was encountered by AVTA related to the installation of the inductive chargers. Because the chargers were new technology and were being installed in two different city jurisdictions, the building inspector required UL field certifications to be accom- plished to ensure there was no shock hazard present. AVTA and WAVE ensured that the UL field certifications were complete as well as the electromagnetic field testing. AVTA will install the industry’s first 250 kW on-route wireless charger later in 2018 and is planning for the same rigorous certification. AVTA paid for the charger installations using local grants from Los Angeles County and the Antelope Valley Air Quality Management district. The agency installed the chargers 50 to 60 feet apart so the communication signals from each charger would not overlap and would not attempt to “handshake” with a bus that was not sitting over the charger. AVTA has planned in advance for power requirements necessary to charge their full BEB fleet expansion. While AVTA has sufficient physical space at the depot to provide for a plug-in charger for every bus, they encountered obstacles regarding the scale up of power supply to support the charging. With two separate power lines (for redundancy) entering the facility at C h a p t e r 6 Case Examples

62 Battery electric Buses—State of the practice AVTA Dashboard BEB fleet size (OEM) Total fleet miles accumulated per month Total months in operation Number of depot chargers Number of on-route chargers Average route length (mi) – BEB Fleet Daily range requirement – BEB Fleet 185 miles Average BEB route speeds BEB cost Depot Charger cost Equipment (per charger) $19,000 Installation (per charger) $55,000 On-route Charger cost Equipment (per charger) $350,000 Installation (per charger) $250,000 Funding sources 2 - 40′ (BYD) 11,581 37 1 21 miles 2 (50 kW inductive/wireless) 17 $770,000 LA County grant, Antelope Valley Air Quality Management District, LA Metro Call for Projects Source: Antelope Valley Transit Authority. Table 12. AVTA BEB characteristics. Jan Feb March April May June July Aug Sept Oct Nov Dec Av. High (çF) 59 62 67 73 82 91 98 98 91 79 67 58 Av. Low (çF) 31 35 39 45 54 61 67 64 57 46 36 30 Source: U.S. Climate Data. Table 13. Antelope Valley average annual climate. Figure 33. AVTA’s battery electric bus. Source: Antelope Valley Transit Authority.

Case examples 63 Figure 34. AVTA’s electrified route, with the blue stars representing the charging stations. Source: Antelope Valley Transit Authority.

64 Battery electric Buses—State of the practice 12.5 kV each, heating due to high current demands from the charger accumulates to a point where the electricity transfer becomes too inefficient. In order to solve this problem, the local utility—Southern Cal Edison—and AVTA decided to install the wiring in an open trench (covered in plates), which allows for safe dissipation of heat and increased system efficiency. The open trenches have the added benefit of being easily serviceable. Initial estimates suggested that operation of the full fleet of BEBs would require 18,000 amps of current to run successfully. Once AVTA built the schedule around the charging manage- ment system and broke it up into four zones with transformers, the estimation decreased to 5,000 amps. AVTA has coordinated closely with their utility to provide rate structure assistance for their growing BEB fleet. Southern Cal Edison has a transportation division and has been very support- ive throughout the deployment process and encouraged the transit agency to go 100% electric. BYD Motors’ buses have an integrated data logger and charge management system from I/O Controls that tracks information about the BEBs. The charging management system allows AVTA to turn the charger on and off, control the charging demands, check battery SOC, and monitor individual driver’s performance. After evaluating bus efficiency performance for their initial fleet of BEBs, AVTA deter- mined that driving style (such as aggressive driving and heavy manual braking instead of rely- ing on regenerative braking) can have a significant effect on bus performance. For example, AVTA reported that two operators on the same route and under the same conditions had a 4 kWh/mile difference in efficiency due to driving technique. This equates to a reduction in range from 220 miles to 80 miles. Training has been an important factor for AVTA to address this issue by teaching efficient operation of the electric vehicles and having trainers ride along on route to re-enforce more effective driving practices. The agency is also considering estab- lishing an incentive program to encourage efficient driving. AVTA’s Advice AVTA encourages transit agencies considering deployment of BEBs to invest in initial prepa- ration. Agencies need to build strong relationships with stakeholder groups, including utilities, bus suppliers, major component suppliers, and funding agencies. Agencies should consider what their ultimate deployment goal is and plan for that and not just for their initial deployment. For example, it makes more economic sense to initially build out all the underground infrastructure rather than to retrofit as the fleet size increases. AVTA was able to accommodate the growth from zero BEBs to 50 much easier than the transition from 50 to 89 BEBs. BEB scale up is chal- lenging due to infrastructure demands, financial requirements, and political preparation, in particular. However, AVTA is on track to complete its “fully green by 2018” goal. King County Metro Located in Seattle, Washington, King County Metro operates 1,474 buses. King County Metro has operated three 40′ Proterra electric buses (pictured in Figure 35) in its fleet since January 2016, accumulating 100,000 miles as part of a pilot project on Routes 226 and 241 as shown on Figure 36 with charging station locations. Local funding and a federal TIGGER grant supported the deployment. King County Metro recently announced that it will acquire 120 additional BEBs by 2020, starting with an order of up to 73 BEBs from Proterra (Fryer 2017). The King County Metro BEB dashboard information is presented on Table 14 as well as climate considerations on Table 15.

Figure 35. King County Metro’s BEB. Source: Fryer. Figure 36. King County Metro’s BEB routes, with the charging station shown as a blue star. Source: Fryer.

66 Battery electric Buses—State of the practice King County Metro’s Experience King County Metro focuses on providing the best operator experience with their BEB pilot program. In doing so, they have established a close working relationship with Proterra, the bus OEM, to address the challenges associated with deploying the new technology and, in particu- lar, the novel ground-up electric bus design. King County Metro needed to ensure that some of the overall design elements of the buses satisfied their operator requirements, such as proper site lines, mirror placement, and regenerative braking feel. Proterra worked closely with King County Metro to address operator feedback and ultimately modified certain design elements of their buses, going as far as building a mock-up driver cabin to test various design options. The relationship that formed throughout the process was not only advantageous to King County Metro because it received better buses but also aided Proterra in product development. Proterra and King County Metro continue to work together to address issues that came to light when validating the buses in King County’s specific operational environment. For instance, bus tuning was required when the transmission began “hunting” between gears on Seattle’s hilly streets. King County Metro currently has one on-route overhead conductive charger, which is located at the East Gate Park and Ride. With the procurement of more buses, the agency plans on add- ing more stations after addressing anticipated challenges with scaling up overhead on-route charging infrastructure. For example, software upgrades will be required so that the chargers can communicate and coordinate signals to “pick up” multiple buses and move them into the correct position for connection to chargers. Because King County Metro is planning to even- tually add three to five more chargers at the park and ride along a common rail, it anticipates King County Metro Dashboard BEB fleet size (OEM) Total fleet miles accumulated (per month) Total months in operation Traction battery size Number of depot chargers Number of on-route chargers Average route length – BEB Fleet Daily range requirements – BEB Average route speeds (mph) BEB cost Depot charger cost Equipment (per charger) $60,000 Installation (per charger) included On-route charger cost Equipment (per charger) $600,000 Installation (per charger) $241,510 Funding sources 3 - 40′ (Proterra) 100,000 12 1 105 kWh 1 (overhead conductive) 18.3 miles 181 miles 15.7 mph $797,882 TIGGER and local funds Source: Center for Transportation and the Environment. Table 14. King County BEB characteristics. Jan Feb March April May June July Aug Sept Oct Nov Dec Av. High (çF) 47 50 54 58 65 70 76 76 71 60 51 46 Av. Low (çF) 37 37 39 42 47 52 56 56 52 46 40 36 Source: U.S. Climate Data. Table 15. King County Metro’s average annual climate.

Case examples 67 having fast chargers next to each other with multiple signals competing to connect to one or more buses within the same proximity. The agency is working with Proterra to determine how the chargers will determine the correct bus to “shake hands with,” control, and charge, which is a technology issue that must be resolved. Another infrastructure challenge that King County Metro and Proterra have experienced involves overhead clearance. If it snows and the bus drives on the packed snow, the height of the bus will be greater and the charger will either have to automatically adjust itself or be raised. Similarly, a semi-truck has already hit the charger because it accidentally pulled into the charging lane. The agency’s solution of raising the charge head would help address both problems, but King County Metro is working on putting up clearance requirements and/or restriction bars for the charging lane as a short-term solution and they have added signage and striping to keep tall vehicles from entering the charger lane. A problem that naturally arises with having three BEBs to one charger is managing the logis- tics of ensuring that each bus is allowed sufficient charge time. Buses currently only overlap charging time slots if there are delays due to traffic. Each BEB’s layover location is 15 minutes at the charging station, but it only takes around 8 minutes for the bus to charge. A minor chal- lenge that King County Metro experiences is that the bus drivers will get out and walk around during the layover, and if another bus pulls up during the layover, the first bus will be done charging but lacking a driver to disconnect and pull out. King County has now made sure the drivers stay near the buses during charging in case another bus needs to charge. King County Metro does have a depot plug-in charger; however, mechanics generally only use the plug-in charger sparingly if at all during maintenance. The plug-in charger functions primarily as a backup. King County is currently evaluating all of the trade-offs associated with depot-charged extended range buses versus overhead fast-charged buses. Seventy percent of King County Metro’s bus blocks are greater than 140 miles and must be provided for. As with other agencies deploying BEBs, King County Metro has worked closely with their two utilities, which have been supportive of the deployment. King County Metro does not actively manage the utility rates, as they have limited options available to them, but they do track the electricity costs. Eventually with the procurement of more buses, King County Metro is likely to shift toward slow charging at the depot and will train employees on smart charging practices, that is, assessing when buses need to be charged and to what extent. King County Metro is also looking to advance support technologies and software to help manage and optimize on-route charging during the day. For example, this could be technologies and software for managing buses that are competing for a charge and letting the drivers know the minimum SOC that a bus needs to have before the driver can pull out of a charge station and still complete the next loop. King County Metro’s training program focuses on informing operators of the key differ- ences between BEBs and conventional buses and how to adapt to them. The biggest obstacle that the agency had to overcome was filtering out “phantom” complaints from real ones; that is, determining if complaints needed to be fixed by the agency or were simply due to the opera- tor not understanding any new or unique functionality of the BEBs. It also found that verifying that operators understood and retained the information through follow-up training was useful. Proterra provides an onsite support person to address issues throughout the warranty period, which has also been helpful for consistent training. King County Metro’s Advice Community plays an important role in the success of a project, whether it is local stake- holders, political leaders, or other transit agencies. The local stakeholders that King County

68 Battery electric Buses—State of the practice Metro involved included the utility companies, climate action nonprofit groups, low-income groups, and people disproportionally affected by the poorer air quality, and it interacted with them by holding community outreach meetings and releasing a “feasibility report” to solicit input on their plans of action. The community input provided a good guideline and not nec- essarily a direct plan of action for the agency. Political leaders played an important role in the project. Their support is critical to program success. King County Metro found it very useful to stay up-to-date on developments and lessons learned in the BEB industry by designating a team from its staff to stay involved in industry committees and meetings, such as APTA’s Zero Emis- sion Bus Standard Bus Procurement Guidelines development committee. According to King County Metro, the factors that a transit agency needs to consider when transforming its fleet to BEBs come down to five questions: What are your service and fleet needs? What are the costs? Do you have supporting infrastructure? What will be the environ- mental impact? What is the financing for the project? After assessing these and other topics, the transit agency will be prepared to move forward with the transition. City of Seneca The City of Seneca (Seneca), South Carolina, provides three fare-free transit routes, includ- ing a business circulator route, a residential circulator route, and an express service linking downtown Seneca to the City of Clemson, Clemson University, and routes within the Clemson Area Transit (CATBUS) system. These routes are shown on Figure 37, with charging stations marked. The City of Clemson is 8 miles from Seneca. Seneca has been operating the “first in the nation” all-electric fleet of transit buses (example displayed on Figure 38) and has demonstrated successes in operability, reliability, cost savings, and environmental benefits. Seneca replaced its three-diesel bus fleet with six Proterra BEBs under three procurements. Seneca prepared extensively for the conversion and approached it with a “no turning back” attitude. Seneca simply considered it a purchase of new transit buses that happened to be alternatively fueled. The BEBs were expected to provide the same level of performance and keep the drivers and passengers as comfortable as the previous diesel buses. These expecta- tions were well defined, and there was a concerted effort to ensure all stakeholders involved shared in these expectations. The bus manufacturer, Proterra, provided assistance to Seneca throughout the entire project and helped the city overcome any technical hurdles with the new technology. CATBUS staff, experienced in bus procurement, was vital to overseeing the construction and deployment of the Seneca fleet. City officials and, in particular, the City Administrator played a pivotal role in engaging the community and involving the appropri- ate stakeholders throughout the process. Seneca’s attitude and approach to their BEB deploy- ment, while relatively small, set a good example for any transit agency looking to deploy BEBs in their fleet. The Seneca BEB fleet dashboard information is presented in Table 16 as well as climate considerations in Table 17. The City of Seneca received awards through FTA’s TIGGER and Livability programs to sup- port the purchase of the all-electric buses. Seneca deployed the buses in 2014, and within a 2-year period the buses had recorded approximately 400,000 miles. Seneca’s deployment is supported by both on-route fast chargers and depot plug-in chargers. Seneca placed its two fast chargers in locations that are served by different electrical grids in case one lost power. Seneca has found that both the bus operators and mechanics rely predominantly on the fast chargers. The buses usually come back to the depot with a 98% battery SOC since the operators prefer to top off charge at the fast charger. Seneca did note that utilizing two separate types of charging infrastructure requires knowledge of separate systems and architecture, but the benefits of having both outweigh any drawbacks.

Figure 37. City of Seneca’s BEB routes, with charging stations at the blue stars on the map. Source: City of Seneca.

70 Battery electric Buses—State of the practice City of Seneca Dashboard BEB fleet size (OEM) Total fleet miles accumulated (per month) Total months in operation Traction battery sizes Number of depot chargers Number of on-route chargers Average route length – BEB Fleet Daily range requirements – BEB Fleet Average route speeds BEB cost Equipment (per charger) $60,000 Installation (per charger) $8,000 Equipment (per charger) $600,000 Installation (per charger) $225,000 Funding sources 5 - 35′; 1 – 40′ (Proterra) 32,818 29 74, 88, 105 kWh 1 2 (overhead conductive) 15 miles 257 miles 40 mph $950,000 TIGGER III, Livability, State Vehicle Replacement Funds, local general funds Depot charger cost On-route charger cost Source: Antelope Valley Transit Authority. Table 16. City of Seneca BEB characteristics. Jan Feb March April May June July Aug Sept Oct Nov Dec Av. High (çF) 52 56 63 72 80 87 90 89 83 73 64 54 Av. Low (çF) 30 33 39 47 56 65 68 68 61 49 40 32 Source: U.S. Climate Data. Table 17. Average annual climate of Clemson, South Carolina. Figure 38. City of Seneca’s BEB. Source: Young.

Case examples 71 Seneca’s Experience Operations. Seneca operates a business loop, a residential loop, and an express route. Buses serve the business loop and the residential loop in a figure 8 manner. Seneca’s operation occurs on a pulse schedule. All buses meet at the Railroad Park transit center in downtown Seneca after each trip and leave at the same time. A pulse schedule allows passengers to easily transfer and connect to the other bus routes. One of the overhead fast chargers is located at the downtown transit center, while the other fast charger is located at a stop midway through the business loop. The express bus takes priority at the downtown charger, while the buses serving the residential/ business loops primarily charge on the business loop charger. If a bus is low on battery SOC, then it takes priority over the others at either charger. All of the drivers communicate to ensure that the buses stay sufficiently charged. Utility Rate Structure. The agency originally was on an electricity rate plan that had demand charges, which involved a flat fee of $13 per kilowatt hour for first demand on each on-route charging station. The fee was assessed at the first use in the month. While intended to help manage utility costs, the rate structure had an unforeseen negative effect: the bus drivers did not want to be the ones responsible for incurring the first demand charge, often in the thou- sands of dollars, at the second station. The fast-charger locations are close enough that drivers opted to charge only at the first station. The resulting overuse of the first charging station caused increased charger traffic at the main station, additional stress on the drivers, and reli- ability issues with the second charger due to lack of use. Seneca then chose to switch to a rate structure with higher energy use charges but no demand fees to alleviate these issues. The energy costs decreased from $1.50 per kWh to $0.90 per kWh. Since switching to the new rate structure, use of the second charging station has increased. However, the new rate structure does not capture the cost of usage as accurately as demand charges do, prompting Seneca to consider switching back to the demand-charge rate. If the city pursues this option, they plan to educate drivers that incurring the demand charge is expected and the cheapest overall option. Performance in a Hot, Humid Climate. Deployment in Seneca was an opportunity to evaluate the performance of BEBs in a hot, humid climate where temperatures reach into the 100-degree range in summer months. There was concern as to how the batteries would perform and react in the environment. In the summer, the battery temperatures start off cool and then naturally increase with each charge cycle on the route loops. While they go through periods of heating and cooling with each loop, the peak temperature gradually increases throughout the day. Seneca found that the best solution is to utilize one of its spare BEBs during hot days and replace the longest route bus, the “express” bus, with a bus that has been sitting at cooler ambient temperatures. Seneca also employs one of Proterra’s “catalyst” buses that have a longer range on the longest route in order to decrease the amount of charge cycles that the bus needs. Seneca’s Advice Seneca encourages any transit agency deploying BEBs to establish a set of key performance indicators at the beginning of the deployment and monitor the results versus results from con- ventional buses. The city had access to detailed utility cost records, which allowed the city to make informed decisions regarding rate structures. The key performance indicators are also useful for tracking and analyzing life cycle costs that are specific to the agency. While it is valu- able to learn from others’ experience, each agency will have its own unique set of operating characteristics that will influence the costs associated with electricity charger siting, electricity rates, environmental effects on bus efficiency and operations, and other factors associated with the deployment.

72 Battery electric Buses—State of the practice Another successful aspect of deployment, CATBUS insisted on a month-long period of shadow service to ensure the BEBs were capable of meeting the same duty cycle of the diesel buses that they were replacing. Not only did shadowing verify the range capabilities of the BEBs but it also rung out any technical issues with the advanced buses. The shadow service was important because it demonstrated that the BEBs would perform comparably to the diesel buses and gave the city of Seneca confidence that the transition to all-electric transit service would be successful. Foothill Transit An evaluation describing Foothill Transit’s BEB operations experience was synthesized in the literature review earlier in this report, but Foothill Transit remains a useful case example as it provides the opportunity for the agency to share additional experience, share considerations, and provide advice. As shown in Tables 18 and 19 and Figures 39 through 41, Foothill Transit’s current BEB fleet consists of 15 35′ Proterra Fast-Charge and two 40′ Proterra Catalyst Fast- Charge BEBs that are supported by two on-route overhead chargers located at the Pomona Transit Center. The 17 fast-charge BEBs have a range of just 35 miles on a single charge and are deployed on Line 291, a 16.1 mile-round-trip route shown in Figure 42. The buses charge at mid- point of the route at the transit center, which is part of the route’s regular stop. Foothill Transit also has a shop charger that it used to charge buses that had undergone maintenance activities, if necessary. Foothill Transit is in the process of expanding its all-electric fleet with an additional 13 40′ Proterra E2 extended-range BEBs and two additional overhead fast chargers that will be installed at a transit center in the City of Azusa adjacent to the Metro Gold Line Station. Foothill Transit Dashboard BEB fleet size (OEM) Total fleet miles accumulated (per month) Total months in operation Traction battery sizes Number of depot chargers Number of on-route chargers Average route length Daily range requirement Average route speeds Bus capital cost Equipment (per charger) Not Applicable Installation (per charger) Not Applicable Equipment (per charger) $500,000 Installation (per charger) $200,000 Funding sources 72 kWh On-route charger cost ARRA, TIGGER, TIGER, Low-No, California HVIP Depot charger cost $789,000 (base price); $823,000 (with add-on equipment) 0 2 (overhead conductive) 16.1 miles 171 miles 10.6 mph 15 - 35′, 2 - 40′ (Proterra) 29,000 Initial order: 3 years and 9 months; Second order: 2 years and 8 months ARRA = American Recovery and Reinvestment Act of 2009; HVIP = Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project. Source: Center for Transportation and the Environment. Table 18. Foothill Transit characteristics. Jan Feb March April May June July Aug Sept Oct Nov Dec Av. High (çF) 68 69 69 74 77 82 89 89 87 80 73 68 Av. Low (çF) 42 44 45 47 51 55 59 59 58 53 45 41 Source: U.S. Climate Data. Table 19. Average annual climate of Pomona, California.

Case examples 73 Figure 39. Foothill Transit’s BEB. Source: Piellisch. Figure 40. Foothill Transit’s 40-ft Catalyst BEB. Source: Foothill Transit. Figure 41. Foothill Transit’s 35-ft Catalyst BEB. Source: Foothill Transit.

74 Battery electric Buses—State of the practice Figure 42. Foothill Transit’s BEB route, with the blue star showing where the charging station is located. Source: Foothill Transit.

Case examples 75 Foothill Transit’s Experience While the NREL report on Foothill Transit does an excellent job of providing a documented comparison between the agency’s CNG and BEB fleets, this TCRP case example focuses on the agency’s experience in deploying electric buses and lessons learned from its operation. One of the biggest maintenance items that the agency has with CNG buses is the engine itself, some of which have been breaking down with only 60,000 miles on them due to premature cracking of pistons in the CNG engines. In addition, the CNG buses require additional consumable products (i.e., oil, filters, and other fluids) to replace during planned maintenance inspections as opposed to just labor hours on BEBs. The BEB propulsion system is much simpler and requires less planned and unplanned maintenance. Battery replacement costs are usually iden- tified as the weakest link for BEBs, but the agency points out that with any internal combustion engine, the transit agency will still have to perform mid-life heavy maintenance, most likely replacing the engine and transmission. However, an admitted trade-off for BEBs in large-scale deployments is the complexity of operations and the need to micro-manage service planning. Foothill Transit expects that in the coming years BEBs and their support tools will continue to advance, which will alleviate this complexity. The agency recently installed an overhead fast charger at its Pomona Operations and Main- tenance facility. Installation of the fast charger would allow the quickest “refueling” and be comparable to the experience of fueling their CNG buses. Installation of fast chargers allows Foothill Transit to address a number of scale-up issues by requiring much less infrastructure than plug-in slow chargers to accommodate its future expansion. Installing the infrastructure to support future deployment presents a challenge for Foothill Transit. The agency lacks the physi- cal space at the depot to install slow chargers to support all planned BEBs. Therefore, overhead fast charging would allow semi-automated, 10-minute charging as the bus is going through the end-of-the-day wash and checkout. Multiple buses can be charged rapidly from a single charger and would help alleviate the space requirements that would be required for having one or two plug-in slow chargers installed per bus, which would ultimately be a more cost-effective solu- tion. As it scales up its BEB fleet with 14 extended range BEBs, Foothill Transit is investigat- ing its bus depot charge strategy and has carefully considered plug-in slow charging as well as strategies such as combining the overhead fast charging with a blocking schedule, in which the buses come into the yard in different waves in order to level out the charge profile. The buses have successfully made the in-service charge connection approximately 95% of the time. The 5% of missed charges is due to a combination of alignment requirements inherent to the charging infrastructure (including the autonomous functionality and geometry), operator error, and lack of sufficient training. In its early deployments of BEBs, Foothill Transit was able to utilize a select, well-trained group of three drivers to operate the buses. However, as the BEB fleet has grown, the agency has expanded the pool of bus drivers, which has affected the level of operator experience. Foothill Transit also adjusted its service in order to balance the layover times and the demand rate and optimize its overall electricity costs. Because the costs substantially increase if the agency goes over a specific amount of power at one time, it decided to reduce its maximum charge power level and extend the layover length from 5 to 7 minutes to remain under the power threshold. Currently within the BEB industry overhead fast-charging methods and equipment are unique to each BEB manufacturer. For instance, a Proterra-supplied overhead fast charger will only fast charge a Proterra BEB, and vice versa. Foothill Transit supports standardization of overhead charging infrastructure in order to allow for interoperability between BEBs and the chargers. An initiative is under way through SAE to address standardization of the charger inter- face for overhead fast charging. The SAE J3105 standard aims to address “on-route conductive charging solutions that serve to promote all day operation of high capacity electric vehicles,” which is currently not addressed in other SAE plug-in charge standards. Standardization and inter operability allow agencies and fleets to invest in fast-charge infrastructure that meets the

76 Battery electric Buses—State of the practice standard and then have the freedom to purchase any bus that also meets the standard and expect that they will safely and effectively work together. This combination thus addresses a barrier to BEB market growth and commercialization. Public interaction with the BEBs has been mixed for Foothill Transit. As with most transit agencies, riders, especially younger generations, generally react positively to the agency’s shift- ing toward more environmentally friendly transportation. However, the agency’s BEBs provide service to a larger portion of the working commuter class as well as to passengers who rely solely on public transit as their means of transportation. Many of these passengers understand that the buses are electric and that they are good for the environment but place a much higher pri- ority on reaching their destination reliably and as fast as possible. Thus they become frustrated and react negatively when the buses require a longer layover and/or have (early stage) technical issues. Additionally, Foothill Transit reported that riders get confused when the bus is docking at the charging station. In the autonomous docking process, the bus will halt for a few seconds after the driver stops and allows the automated process to take control. Passengers or people around the bus then assume that it is stopped and proceed to stand up or walk in front of it. The bus then lurches forward again, shifting on-board passengers or startling passengers attempting to pass in front of the bus or stow bikes. For these reasons, on a scale of 1 to 10 with 10 being the most positive, the agency gives its public’s reaction a rating of 6. Early in deployment, Foothill Transit also encountered issues with pranksters pushing the Emergency Stop button on the overhead charger at the transit center. The agency put a plastic covering over the button with a sign saying that the area is under surveillance, which helped cut down on the incidents, but the button is still pushed on occasion. Foothill Transit’s Advice Partnering with the local utility, as has been mentioned in other case examples, proved to be a vital part of Foothill Transit’s BEB program development. While the agency’s utility, SCE, was involved early in the process, they were originally not aware of the agency’s intentions to scale up their BEB fleet. Issues arose regarding application of electricity rates—the agency had initially obtained a waiver from demand charges by the California Public Utilities Commission, which expired in December 2015. Foothill Transit’s advice is to engage the utility early in the planning process for BEBs and understand the impacts of the planned scale-up deployment on the transit agency’s energy needs. Prior to engaging with the utility, the transit agency needs to have an understanding of the power requirements on the planned routes. Modeling and simula- tion were useful tools for Foothill Transit because they allowed for energy and power demand projections in different operating environments, for example, fluctuations in temperature due to seasonal changes. The agency also emphasized the value of stakeholder involvement. The agency suggested early engagement with any groups or individuals who may be affected or who may need to support the deployment of BEBs. Educating groups such as the yard managers, permitting agencies, community groups, and the board of directors regarding both the limitations and the benefits of BEB technology will help the project run more smoothly. Foothill Transit was fortunate to have two internal support staff, or champions, working on the BEB program—one of whom was focused on technical aspects and one of whom was focused on legislative issues. The technical staff handles anything regarding operations, while the legislative staff not only manages fund- ing opportunities but also interacts with the utility companies and other political stakeholders. Foothill Transit would encourage as many champions as feasible to help support a successful BEB program.

Case examples 77 IndyGo Dashboard BEB fleet size (OEM) Total fleet miles accumulated (per month) Total months in operation Traction battery size Number of depot chargers Number of on-route chargers Average route length – BEB Fleet Daily range requirements – BEB Fleet Average route speeds Bus capital cost Equipment (per charger) $10,000 Installation (per charger) $5,000 Equipment (per charger) Not Applicable Installation (per charger) Not Applicable Funding sources TIGER On-route charger cost 305 kWh 22 0 90 miles 150 miles 21 - 40′ (Complete Coach Works) 500 16 Depot charger cost 15 mph $579,000 Source: Center for Transportation and the Environment. Table 20. IndyGo BEB characteristics. Jan Feb March April May June July Aug Sept Oct Nov Dec Av. High (çF) 36 40 52 63 73 82 85 84 78 65 52 39 Av. Low (çF) 20 24 33 43 53 62 66 64 56 45 35 24 Source: U.S. Climate Data. Table 21. Average annual climate of Indianapolis. IndyGo As shown in Tables 20 and 21 and Figures 43 and 44, the Indianapolis Public Transport Corporation, IndyGo, currently has 163 buses, including 21 BEBs. IndyGo used funding from a $10 million Transportation Investment Generating Economic Recovery grant awarded in 2013 to deploy 21 40′ BEBs provided by Complete Coach Works, which converted IndyGo’s existing GILLIG low-floor buses with its zero emissions propulsion system. IndyGo is also in the process of procuring 13 additional 60′ articulated buses to begin electrification of their Bus Rapid Transit lines. IndyGo utilizes depot charging to support the BEBs that serve routes that are an average of 90 miles long. IndyGo stressed the importance of involvement and education of political stake- holders as well as robust, continued BEB training for drivers and mechanics. IndyGo’s Experience One of the early challenges for IndyGo was identifying the different ways in which problems were manifesting themselves and determining what was normal for the technology and what was not normal. Recurring issues versus isolated issues were identified as well. Early in the deploy- ment of advanced technology buses, it is difficult to fully train maintenance personnel on the technical details of the new systems, especially troubleshooting. As with many new technologies,

78 Battery electric Buses—State of the practice Figure 43. IndyGo’s BEB. Source: Complete Coach Works. a simple reboot of the system becomes the general protocol when maintenance staff runs into problems, but it does not necessarily address the root cause of the problem. Furthermore, some- times technical details and resulting impacts can be misunderstood or lost in translation, espe- cially when communicating issues and solutions to project stakeholders. Addressing the political needs, both internal and external, associated with a high profile project can also be challenging and was an important, early lesson to learn for IndyGo. Politi- cal needs and desires must be addressed in order to sustain support and funding for a project; however, they can sometimes compete with the needs of the technology. Competing needs and desires must be carefully weighed and addressed by the project coordinators. IndyGo also reported that incorporation of a BEB fleet presents unique challenges that are outside the norm for a transit agency and that require careful communication as they are addressed. Minor issues regarding systems that management may not be familiar with can inadvertently be perceived as big issues. Therefore, education and proper framing of issues become important when report- ing project status. IndyGo has found that drivers can forget some of the unique operating characteristics asso- ciated with BEBs when they switch between diesel buses and BEBs, an omission that can be addressed with recurrent training. IndyGo’s training department now hosts annual in-service training in an effort to continue to educate drivers and ensure the most efficient and effective operation of the BEB fleet. IndyGo also received support from the bus OEM, Complete Coach Works, which provided a resident trainer for mechanics that guides a team specifically dedicated to electric vehicle maintenance. IndyGo supports their deployment with 22 plug-in depot chargers. Depot charging was a more viable option than on-route fast charging because the routes are sometimes adjusted for events and detours, such as when there is a parade. IndyGo reported that the operation of 22 depot chargers requires significant power to meet the demand. To help manage the load, IndyGo established two different circuits to serve the bus islands. IndyGo also supple- mented their electricity demand by installing solar panels. The 1-megawatt solar panels were funded through a $3 million State of Good Repair grant through the Federal Transit Admin- istration. The panels were installed on the garage roof and provide the energy required by almost all of the chargers. For scaling-up BEB deployments, the agency is considering adding a battery bank or building a canopy over the workers’ parking lot that would allow for the installation of additional solar panels. IndyGo has a charger for every BEB bay and stated that the plug-in process goes smoothly. IndyGo currently relies on their general service employees on the night shift to plug in the

Case examples 79 Figure 44. Sample of the routes on which IndyGo deploys BEBs. Yellow star represents the depot where IndyGo houses its 22 chargers. Source: IndyGo.

80 Battery electric Buses—State of the practice vehicles. Supervisors provide the oversight during their normal walk around to ensure the charg- ing is properly started. Drivers unplug the buses in the morning before beginning their routes. IndyGo procured the charging infrastructure separately from the BEB procurement, but the process was simple and they encountered no difficulties in coordinating the two deployments. IndyGo is also considering chargers with plug-in cords that drop down into the bays, but this is still in the preliminary planning stages. IndyGo’s Advice As with the deployment of any new technology, setbacks and challenges are expected. IndyGo’s advice to any other transit agency considering deployment of BEBs is to manage expectations, both internally as well as externally. Similarly, IndyGo advises to establish a business case and continue to use it to direct the course of action, paying special attention to the characteristics specific to that transit agency. As mentioned, IndyGo utilizes depot charging because they adjust routes from time to time and have plenty of space to locate the chargers. Also, IndyGo would encourage transit agencies considering deployment of BEBs to look to agencies of a similar size that are already operating BEBs for advice—peers are one of the best resources to truly understand the technology and the benefits and challenges associated with deployments. Case Example Summary The case examples allow the transit agencies to give any advice to those agencies that are con- verting to BEBs. The City of Seneca emphasized asserting that BEBs are expected to perform like diesel buses. The agency obviously understood the limitations with the new technology, but the high expectation kept the project under way. To keep the expectation prevalent in the planning and operation stages, an agency could hold community stakeholder meetings and ensure back- ing of the project all the way up the chain of command, as King County suggested. King County also found that paying attention to other agencies’ practices and developments throughout the process was advantageous but, according to IndyGo, the observed agencies should be similar in size to the on-looking agency. Both Foothill Transit and AVTA suggested keeping the full busi- ness plan in mind when making preliminary decisions. However, to have a comprehensive yet successful business plan, all five agencies recommended having at least one or two champions of the project, according to Foothill Transit, to lead it around obstacles.

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TRB's Transit Cooperative Research Program (TCRP) Synthesis 130: Battery Electric Buses—State of the Practice documents current practices of transit systems in the planning, procurement, infrastructure installation, operation, and maintenance of battery electric buses (BEBs). The synthesis is intended for transit agencies that are interested in understanding the potential benefits and challenges associated with the introduction and operation of battery electric buses. The synthesis will also be valuable to manufacturers trying to better meet the needs of their customers and to federal, state, and local funding agencies and policy makers.

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