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Battery Electric Buses—State of the Practice (2018)

Chapter: Chapter 5 - Survey Results and Post-Deployment Experience

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Suggested Citation:"Chapter 5 - Survey Results and Post-Deployment Experience." 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 5 - Survey Results and Post-Deployment Experience." 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 5 - Survey Results and Post-Deployment Experience." 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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Page 57
Suggested Citation:"Chapter 5 - Survey Results and Post-Deployment Experience." 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.
×
Page 57
Page 58
Suggested Citation:"Chapter 5 - Survey Results and Post-Deployment Experience." 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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Page 59
Suggested Citation:"Chapter 5 - Survey Results and Post-Deployment Experience." 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.
×
Page 59
Page 60
Suggested Citation:"Chapter 5 - Survey Results and Post-Deployment Experience." 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.
×
Page 60

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54 Training Transit agencies reported training an average of 70% of their drivers and an average of 58% of the maintenance staff to support their BEBs. Operations and maintenance training was pre- dominately provided by the bus OEM for both the bus and the supporting infrastructure. The transit agency, equipment providers, and third-party organizations also occasionally supple- mented this training. Sixty-one percent of respondents stated local first responders were also trained in responding to BEB incidents. Most transit agencies found that the OEM was well prepared and invaluable to the training process. However, one agency encountered a bus OEM trainer who initially was not appropri- ately prepared to conduct the training, but this appears to have been an early deployment for the OEM. In general, training obstacles that transit agencies encountered were • The unfamiliar nature of SOC for new operators—the agency suggested providing an esti- mated range (time of operation remaining) for them, • Understanding range capacities of different products and batteries, and • Uninformative training manuals. Some training practices that worked well for agencies include • Training in smaller groups for one-on-one development, • Hands-on training with the bus present, • Working with third party trainers, • Having a factory technical representative on site and operating an initial shadow service because it gave the agency the flexibility to pull BEBs off the line to train personnel, • Training first responders, and • Training the drivers and first responders together for consistency in the response methods. Operations Respondents are operating anywhere from two to 18 BEBs during peak periods, with an aver- age of six buses operating for all respondents. A primary consideration with integrating BEBs into a fleet is the potential need to adjust their existing operations to support bus charging. To accommodate the unique operational needs of BEBs, 60% of respondents had to adjust their schedule. Layover times were the second most adjusted at 40%, followed by bus blocking at 20%, and number of buses serving a route at 13%. However, 33.3% of transit agencies did not make any adjustments. Although some bus OEMs define maximum SOC, minimum SOC, and expected operating range differently, the buses generally left the depot with battery SOC above C h a p t e r 5 Survey Results and Post-Deployment Experience

Survey results and post-Deployment experience 55 90%. As expected, SOC upon return varied widely depending on bus service and charge method, with the minimum reported SOC at 25%, as shown in Figure 29. Generally, the transit agencies reported that BEB operations went smoothly, the buses worked well, and there were minimal problems. However, some issues were noted in the sur- vey responses. For one agency, bus energy consumption was greater than anticipated during the winter months and fleetwide modifications had to be made to the heating system. Another transit agency struggled with ensuring that the BEBs have ample time to charge when unplanned events occur, like a late plug-in to the charger and following missed charge opportunities. It is important to note that these issues are unique to BEBs and can be addressed with proper analysis and planning early in the deployment. Respondents were split when asked whether it was important to avoid making manual con- nections to a charger. Some respondents said it was fine and easier to plug in a BEB than to fuel a CNG bus. Other respondents said it would be easier to have the connections be automated and avoid reliance on human interface, which can introduce risk of error (i.e., missed charges) and oversight requirements. Availability and Reliability On-route charging can be extremely useful because it can enable BEBs to meet extended range and duty cycle requirements. One agency reported that their BEBs remain charged with- out having to return to the depot and could easily operate 24/7. However, they also stated that it can be risky for the agency to rely solely or primarily on on-route chargers because if one charger goes down, service is affected. Even with multiple chargers at the same location for redundancy, power outages will affect service. Many agencies plan for such risks by having multiple buses charging at the depot or deploying backup diesel or CNG buses. The general consensus of agen- cies is that on-route charging works well as long as there is adequate planning, testing, training, and practice docking. In general, after going through the process of initial deployment and 0 20 40 60 80 100 120 Depot only On-route Depot only On-route R et ur n fr om se rv ic e (% ) De pa rt fo r s er vi ce (% ) Operations Experience: Battery State of Charge Maximum Average Minimum Figure 29. Operations experience: battery SOC with respect to the agency’s charging method (n = 13). Source: Center for Transportation and the Environment.

56 Battery electric Buses—State of the practice shakeout, agencies reported that BEB availability was an average of 86%, depot charger avail- ability was 99%, and on-route charger availability was 86%. Most agencies using on-route charging reported that 90 to 95% of charges attempted were successfully made. The lowest reported successful connection rate was 75% of the time. Charges were missed due to a variety of reasons, including mechanical malfunction of chargers, buses behind schedule, misalignment, loss of power to chargers, and blocked paths. When asked if it was important to provide audible or visual communication to pedestri- ans that the bus was approaching, 72% of the agencies said yes. Some recommendations for communicating approach included combinations of visual and audible cues, interactive signs, mobile application notifications, and technologies that communicate the bus IT systems to monitor conditions and provide notification. The respondents did not believe that it was important to provide audible or visual communication to passengers that a bus is charging. Service and Maintenance Respondents reported that BEB and associated charging infrastructure maintenance was provided by the bus OEM, a third party, or the transit agency itself. As highlighted in Figure 30, the majority of transit agencies rely on their staff to provide the maintenance on BEBs and preventive maintenance and repair on the charging infrastructure. However, bus manufacturers provide maintenance support on the advanced propulsion systems and charging infrastructure. 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Bus propulsion system preventive maintenance Bus propulsion system repair Charging infrastructure preventive maintenance Charging infrastructure repair Who provides the following services and maintenance? Bus OEM Third Party Transit Agency: In-house Figure 30. Bus service and maintenance providers (n = 14). Source: Center for Transportation and the Environment.

Survey results and post-Deployment experience 57 A majority of the agencies (79%) reported no issues with the traction battery. An early con- cern associated with traction batteries is battery degradation and end of life, but most of the respondents (54%) do not track that data. The agencies that do track that data are reliant on the bus OEMs to test and provide that information upon request. Agencies report that spare parts inventories for BEBs are either the same (46%) or lower (46%) compared with diesel buses because BEBs require fewer components and because some components, such as brakes, do not need to be replaced as often. However, parts availability and long lead times have been problematic due to the relatively small scale of BEB deployments and the lack of a mature supply chain. The agencies reported very little maintenance issues and liked the relative simplicity of the vehicles. The challenges that agencies have encountered with BEB maintenance center on the learning curve associated with the new technology, which can be addressed with robust training programs and, ultimately, experience. Costs A majority of the transit agencies are tracking their costs, including capital costs and main- tenance and operational expenses. Capital costs were covered earlier in this chapter. An impor- tant component of operational costs is unscheduled maintenance requirements. In a direct comparison of maintenance costs, CNG bus costs are reportedly less according to one agency; BEB costs are $0.09 per mile, and CNG bus costs are $0.12 per mile. Table 11 presents the dis- tribution of the operational costs associated with the BEBs based on the survey. Care must be taken when considering these reported costs since they are heavily dependent on utilization of the buses. If the buses were not utilized to their fullest potential, then operational costs per mile would rise significantly and could be misleading. The agencies reported electricity costs of anywhere from $0.15 per mile to $0.89 per mile, with an average of $0.36 per mile. This massive range (almost 600%) in fuel costs is likely due to the broad range of utility charges across the country and complex rate structures. It could also be due to underutilization of the buses when demand charges are in place. Note that NREL reported that the battery electric bus fuel cost was $0.39 per mile compared with the $0.23 per mile for the baseline CNG buses during the evaluation period. Electricity rates and their optimal use must be better understood by the industry (and, in particular, utilities) in order to get fuel costs down to, or below, those for conventional buses. For a cost comparison, the survey polled the agencies on two different categories: actual BEB cost to original budgeted amount and BEB cost to existing diesel or CNG buses. In compari- son with budgeted amounts, responses varied equally that actual costs were less than, greater than, or equal to budgeted amounts. It is not surprising that the actual capital costs of BEBs were reported to be greater than existing diesel/CNG buses; however, 46% of respondents Costs ($/mile) Min Avg Max Scheduled Maintenance 0.09$ 0.36$ 0.92$ Unscheduled Maintenance 0.09$ 0.28$ 0.55$ Fuel/electricity for BEB Fleet 0.15$ 0.36$ 0.89$ Source: Center for Transportation and the Environment. Table 11. BEB operational costs.

58 Battery electric Buses—State of the practice reported that operations and maintenance costs were less than those of their diesel/CNG fleet. Twenty-three percent reported that BEB O&M costs were greater than their conventional fleet. As previously mentioned in the literature review, government or state funding can be used to help offset capital costs. When asked about life cycle costs compared with budgeted or conventional fleet costs, many of the agencies stated that they were unsure due to the early stage of commercialization of BEBs and not having enough data, as shown in Figures 31 and 32. One agency stated that they “did [have] a very high level analysis of the BEBs cost. However we are trying to fine tune that as we implemented sub-meters to take data more accurately.” One takeaway is that there simply is not enough data yet to begin to understand true BEB life cycle costs. Social, Environmental, and Health Benefits Fifty-three percent of respondents do track the social, environmental, and health benefits of BEBs, specifically those related to greenhouse gas (GHG) emission reduction. The California agencies tracked GHG emission estimation because many of them used state funds with require- ments for tracking. In general, the public reaction to BEBs was reported to be high on a scale of 1 to 10 (60% positive, with a rating between 5 and 8; the rest being very positive with a rating of either 9 or 10). One agency reported that, when compared with the buses it has replaced, it is avoiding more than 3,000 pounds per year of criteria air pollutants with its fleet of 15 BEBs. Another agency utilized the Diesel Emissions Quantifier Health Benefits Methodology (U.S. Environmental Protection Agency 2010) to track its pollutant reductions, as reported below. • “Carbon dioxide (CO2): a 121-ton reduction per year, per electric bus. Over the anticipated 12-year lifetime of the bus, this equates to 1,452 tons per bus. 0 Capital Costs Operation and Maintenance Costs Life Cycle Costs 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Pe rc en ta ge o f T ra ns it A ge nc ie s Cost Comparison: Actual BEB Cost to Original Budgeted Amount (%) Greater than Less than About the same Not sure Figure 31. Actual BEB costs versus original budgeted amount (n = 12). Source: Center for Transportation and the Environment.

Survey results and post-Deployment experience 59 • Hydrocarbons (HC): reduced by 0.0428 tons per year or 0.5136 tons over the 12-year lifespan of each bus. • Carbon monoxide (CO): reduced 0.310 tons annually or 3.72 tons over the lifetime of the bus. • Nitrogen oxides (NOx): less 0.5938 tons per year, or 7.1256 tons over the lifetime of the bus. • Particulate matter (PM): reduced by 0.0274 tons per year, or 0.3288 tons over the 12-year lifespan of each electric bus” (U.S. Environmental Protection Agency 2010). One agency responded that merchants and residents like the quiet operation of the buses. Resiliency and Emergencies Finally, for resiliency and emergencies, 57% of respondents provide assistance for com- munity critical functions, such as evacuations, mobile climate center, and temporary shelter that may require them to consider backup power generation by using the BEBs or consider additional battery storage capacity. Most of the agencies (86%) would expect to have some assistance in place 2 hours after an event or an outage takes place. A common method, accord- ing to responses, is to have back-up generators. One agency can use its BEBs as a power source for vehicle-grid technology: vehicle-to-building or V2B, vehicle-to-load or V2L, and bidirec- tional vehicle-to-grid or V2G services. Other agencies believe that emergency support with BEBs is not feasible at this early stage due to long-range support requirements. One respondent stated that “The current and near term BEB percentage of the fleet is far too small to require planning of that nature.” And another respondent stated that “We would not use the BEB in these situations, and likely would not go to a 100% fleet for that reason.” 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Capital Costs Operation and Maintenance Costs Life Cycle Costs Pe rc en ta ge o f T ra ns it A ge nc ie s Cost Comparison: BEBs to Existing Diesel/CNG Buses (%) Greater than Less than About the same Not sure Figure 32. Battery electric buses cost versus existing diesel/CNG buses cost (%). Source: Center for Transportation and the Environment.

60 Battery electric Buses—State of the practice Stakeholder Involvement Stakeholder involvement is an important part of the BEB procurement and deployment process, as later emphasized in the case examples of this synthesis. Common stakeholders include utility companies, operators, unions, communities, executive boards, and regulatory agencies. According to the survey responses, regulatory agencies repeatedly suggested dem- onstrating the positive environmental impacts and operational cost savings of BEBs in order to engage stakeholders, such as executive boards and communities, and to motivate them to support the process. One agency stated that some stakeholders question BEB effectiveness due to increased power plant emissions as well as the upfront costs of the buses. These items, in particular, need to be analyzed and addressed early in the BEB procurement process in order to make an objective case for stakeholders. One respondent also stressed the importance of strategic planning to determine the best BEB type for the given operation, as well as effective placement of charging stations. Overall Satisfaction with BEBs Overall satisfaction with BEBs was very positive. On a scale from 1 to 10, 77% of respon- dents are either satisfied with the BEBs (ranking between 4 and 7) or very satisfied (ranking between 8 and 10), and 86% of the reporting agencies plan on purchasing more BEBs. While one agency has already gone fully electric, three agencies responded that they intend to be fully electric by years 2018 (with 79 buses), 2025, and 2030. One agency even reported that they plan to replace their 17-year-old BEBs with new BEBs soon.

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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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