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Guidebook for Deploying Zero-Emission Transit Buses (2021)

Chapter: Phase 9 Data Monitoring And Evaluation

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Page 122
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
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Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
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Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
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Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
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Page 125
Page 126
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 126
Page 127
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 127
Page 128
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 128
Page 129
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 129
Page 130
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 130
Page 131
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 131
Page 132
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
×
Page 132
Page 133
Suggested Citation:"Phase 9 Data Monitoring And Evaluation." National Academies of Sciences, Engineering, and Medicine. 2021. Guidebook for Deploying Zero-Emission Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/25842.
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Page 133

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122 9.1 Overview Data analysis provides insight into how the buses are performing in your service area and if they are being fully utilized. The results can inform operational changes that will allow you to get the most out of your ZEBs, help you understand the true costs and benefits of the deployment, and inform future needs for a ZEB fleet. In addition, data monitoring, tracking, and reporting leads to early identification and mitigation of deployment issues. Reports can also satisfy any reporting requirements from federal, state, or local grants. Common KPIs for ZEB deployments are: • Fuel cost per mile, • Energy performance, • Availability, • Utilization, • Fleet comparisons, • Emissions reductions, • Maintenance costs, and • Ongoing lifetime cost analysis. Best practices for data monitoring and evaluation include: • Defining KPIs and metrics for reporting. • Identifying and coordinating internal and external sources for operations and maintenance data. • Ensuring bus performance data is developed for fair and accurate reporting of metrics, especially when compared to non-ZEB vehicles and vehicles of different ages . PHASE 9 DATA MONITORING AND EVALUATION

Data Monitoring and Evaluation 123 9.2 Key Stakeholder Considerations Project Managers • Develop reports, as requested from executive leadership and transit agency staff, and as required by federal, state, or local funding sources used to support the ZEB deployment. • Coordinate with bus and infrastructure OEMs, electric utility providers, and operations and maintenance staff to establish data collection procedures for ongoing reporting. Operations, Maintenance, and Facilities • Ensure procedures are in place for capturing ZEB mileage, block assignments, service data, and daily availability. • Develop availability metrics to distinguish issue causes. • Track ZEB maintenance activities and costs for the duration of ownership (both during and after warranty periods). Procurement • Review contracts to ensure access and rights to the desired bus and fueling infrastructure data. • For FCEB deployments, notify project managers upon renewal of hydrogen fuel contract pricing. External Stakeholders • Bus and fueling infrastructure OEMs should be notified of data needs and access requirements prior to bus deployment.

124 Guidebook for Deploying Zero-Emission Transit Buses 9.3 Data Collection and Reporting After your ZEB fleet is in revenue service, collecting and analyzing bus data will help you better understand the performance, reliability, durability, and cost of your deployment. Evaluating the performance and limitations of the technology allows you to determine the most effective and efficient use of the buses throughout your service area. Operations, maintenance, and planning staff should use ZEB performance data to optimize bus scheduling; monitor fueling, operational, and maintenance costs; calculate emission reductions; and evaluate variables that may impact performance (Figure 9-1). Non-ZEB fleet data should be utilized as well to understand how the technology compares to other vehicles in your transit agency’s fleet. Periodic ZEB performance reports will inform your transit agency’s board or executive leadership on deployment success and help build a business case for future deployments. If your ZEBs were purchased with state, federal, or other local funds, funding providers may also require periodic reporting. ZEB operational data can also be used in promotional materials to advertise your transit agency’s commitment to the environmentally friendly technology. Your transit agency should determine what metrics define and measure the success of your ZEB deployment, and reports should be developed to ensure fair and accurate measurement of those metrics. There are several KPIs that are commonly used to evaluate ZEB deployments, including: • Fuel cost per mile (Figure 9-2): Track fuel costs per mile to determine if bus operations are in line with your estimates. Since transit agencies typically track fuel costs per mile, this is the easiest metric for comparing ZEB and non-ZEB vehicles. For ZEB technology, cost per mile also allows transit agencies to see the impact other factors (e.g., weather, topography) have on deployment costs. This metric also serves as the basis for calculating diesel gallon equivalent fuel efficiencies. Data collection and validation can be burdensome, if data is required from disparate sources. Ongoing coordination between OEMs, transit agency departments, and potential third parties will be needed. Figure 9-1. Example KPI metrics.

Data Monitoring and Evaluation 125 BEB: Fuel costs measure electricity costs to charge the buses. If possible, separately meter or submeter charging infrastructure to understand the exact charger kWh consumption. If charger consumption data is not itemized on your utility bill, utilize bus kWh consumption and grid-charger- bus efficiency loss approximations to estimate grid energy consumption. Alternatively, you can install separate three phase power measurement in your switchgear cabinet to measure the input to each charger. Your measured kWh consumption in conjunction with your utility rate schedules will determine your energy cost. Fuel costs per mile for your BEB fleet will depend on your rate schedule and the number of miles driven. Once optimized, monthly demand charges do not vary significantly since they are based on your peak power, regardless of the miles driven. Therefore, the more miles your BEB is driven in a given month, the more miles the demand charges are spread over and lower the fuel cost per mile. FCEB: Fuel costs measure costs of delivered hydrogen or raw materials for hydrogen produced on-site, as well as electricity costs to operate the fueling station. Separate or submetering of fueling stations will provide the most exact electricity consumption data. Discuss demand-metering options with your electric utility provider to ensure you achieve the charger-specific kWh consumption visibility you desire without unintentionally eliminating any benefits from scheduling charges during low facility demand periods (See Section 4.3.5: Demand Charges). Figure 9-2. Example KPI of average fuel cost per mile for non-electric and electric buses(for illustrative purposes only, values do not reflect actual deployment data).

126 Guidebook for Deploying Zero-Emission Transit Buses • Energy performance (e.g., kWh/mile, miles/kg H2) (Figure 9-3): The energy performance and energy efficiency of your ZEB fleet will inform range, identify any seasonal variability, and identify energy efficiency trends by route or operator. Cross-referencing energy efficiency with temperature or auxiliary usage will allow you to see how temperature and related HVAC loads impact efficiency. BEB: Energy efficiency is typically measured in kWh/mi. While the most accurate and comprehensive measure of kWh consumption will come from a charger-specific meter or power measurement, this may have its limitations if buses share chargers. If charger-level data is unavailable, data monitoring programs from the OEM or a third-party provider can provide the energy (kWh) consumed by the bus, or calculate kWh/mi. For these services, ensure you understand how kWh measurements are taken and what consumption it includes. As a final alternative, you can estimate kWh consumed by the bus with the following expression: kWh consumed = % SOC used × battery nameplate capacity (kWh) Energy consumption (kWh) provided by OEMs or third parties does not typically account for any grid-to-charger or charger-to-bus loss. While this data is useful in understanding efficiency of your bus, it does not equate to the actual kWh consumption you would be charged for on your utility bill. Additionally, buses may have standby energy consumption that is not reported as energy used while driving. Figure 9-3. Example energy performance KPI, showing kWh/mi by temperature (for illustrative purposes only, values do not reflect actual deployment data).

Data Monitoring and Evaluation 127 • Availability (Figure 9-4): Availability will indicate know how often the ZEB fleet was able to be put into service. NREL typically uses the following categories for availability: o In-service (road calls should also be tracked on days when the bus is put into service), o Event/Demonstration , o Not used, o Training, and o Not available to be put into service due to one of the following reasons (Table 9-1): Table 9-1. NREL-recommended categories for bus unavailability. BEB FCEB Energy storage system Fuel cell system Electric drive Hybrid propulsion system Traction motor Traction batteries Preventative maintenance Preventative maintenance General bus maintenance General bus maintenance If estimating kWh consumption using bus SOC, be aware that this method has the potential to be inaccurate for a number of reasons. To start, SOC is hard to measure accurately. Additionally, some bus models report an SOC on the dash that is different than the actual SOC. Be careful when calculating kWh consumption using SOC. It is better done by pulling energy used at the meter or bus charger and dividing it over total miles driven. FCEB: y measured in kg HEnergy efficiency is typicall 2/mi or kg H2/100 km. Utilize your fueling records to determine the volume of hydrogen consumed.

128 Guidebook for Deploying Zero-Emission Transit Buses Your transit agency can define additional categories if helpful, such as “Road Call for Low SOC.” Reporting availability monthly will allow you to track maintenance issues that kept buses out of service. ZEB availability may be dependent on charging or fueling infrastructure availability. This may be particularly true for BEBs that utilize on-route fast chargers, as there may be less redundancy in charging equipment. Hydrogen fueling station and charger availability should also be tracked in your data collection efforts. • Utilization: Utilization measures the actual usage of your ZEB fleet compared to the possible usage. It can be measured by comparing the number of days a bus was actually put into service to the total days it was available to be put into service. Low utilization could indicate that there are operational issues, such as there not being enough operators trained on ZEBs. Tracking utilization can help your transit agency identify the root cause of issues and address them, helping you meet your ZEB usage goals. While availability may be reported monthly, ensure that data is collected weekly, as it may be difficult to recount reasons for bus unavailability weeks after the fact. Figure 9-4. Example availability KPI (for illustrative purposes only, values do not reflect actual deployment data).

Data Monitoring and Evaluation 129 • Fleet comparison (Figure 9-5): Comparing the performance of the ZEB fleet to the diesel, CNG, or hybrid fleets informs relative cost and performance. Comparing mileage and availability will allow you to see if the buses provide similar service. Many transit agencies compare fuel economy, fuel costs per mile, and maintenance costs per mile. Ensure that the cost and performance variables you are tracking are equitable to allow for a fair comparison between fleets. You can compare fuel economy for ZEBs by calculating miles per diesel gallons equivalent (mpDGE) for the fleet. The following conversions take into account the energy content of hydrogen and electricity to calculate diesel gallons equivalent (DGE): DGE for BEBs = total kWh consumed / 37.64 DGE for FCEBs = total kg H2consumed / 1.13 • Emissions reductions[e.g., gallons of diesel avoided, carbon dioxide (CO2) emission reductions]: Figure 9-5. Example KPI for comparing fleet fuel efficiency (for illustrative purposes only, values do not reflect actual deployment data).

130 Guidebook for Deploying Zero-Emission Transit Buses The environmental benefits of ZEBs are a driving force for many transit agencies’ deployment projects (Figure 9-6). The Environmental Protection Agency (EPA) and other environmental organizations provide GHG emission estimates by diesel gallons avoided or miles travelled. Common GHGs associated with diesel combustion include (CO2), carbon monoxide (CO), nitrous oxides (NOx), volatile organic compounds (VOCs), and particulate matter (PM). Use the fuel economy for your conventionally fueled buses to estimate gallons of diesel avoided from BEB operation. • Net health benefit: In addition to the calculating of GHG emission reductions, more and more cities are calculating a net health benefit as well, since those same reductions also reduce the incidence of health problems from PM in those emissions (Figure 9-7). A team of scientists at Lawrence Berkeley National Laboratory (Berkeley Lab), the National Institute of Environmental Health Sciences (NIEHS), RAND Corp., and the University of Washington has calculated the economic benefit of reduced health impacts from GHG reductions strategies to be between $40 and $93 per metric ton of carbon dioxide reduction (Balbus et al., 2015). Figure 9-6. ZEBs eliminate harmful emissions from diesel vehicles. Be sure to account for CO2 emissions from the production of electricity. The U.S. Energy Information Administration (EIA) provides estimates of CO2 produced per megawatt-hour (MWh). Figure 9-7. Health impacts of air pollution. (Image Source: World Health Organization)

Data Monitoring and Evaluation 131 • Lifetime costs analysis (Figure 9-8 and Figure 9-9): Compare the actual operating and maintenance costs to the projected costs throughout the service life of the fleet. Utilize similar data for your non-ZEB fleet to create a comparison across vehicle technologies as well. For maintenance costs, include all maintenance activities and mid -life rebuild/replacement activities. Be sure to create a method for tracking any activity during the warranty period as well. While service during that period may be covered by your OEM, it is important to understand what maintenance activity has been required. This information can help inform expectations going forward. Reports need to ensure fair comparisons between different vehicle technologies and different vehicle ages; care should be taken to ensure cost and performance data is comparable. Try to match the topographical features of routes each fleet type is deployed on and ensure that all factors needed to calculate costs are included. Figure 9-8. Example KPI comparing cumulative maintenance costs (for illustrative purposes only, values do not reflect actual deployment data).

132 Guidebook for Deploying Zero-Emission Transit Buses 9.4 Data Sources You may need to collect data from several, disparate sources to support robust data reporting for your ZEB fleet. • Utility bills: Use the total costs from your electricity bills to calculate fuel costs per mile. Compare the total kWh billed to the energy consumption data from other estimations or data sources (i.e., OEM or third-party data monitoring systems) to understand efficiency loss between the grid, the charger, and the bus. • Data monitoring services: o OEM platforms: Some OEMs provide a data monitoring platform to track performance data. Most platforms allow you to view detailed energy consumption data, and track SOC, mileage, charging, and other metrics. Coordinate with your OEM to understand your available options for accessing data monitoring portals or performance summaries. Be sure you have a clear understanding of what is being reported and how it is calculated/provided. o Third-party platforms: Third-party solutions can provide real-time data on your ZEB fleet. These services will work across OEMs to allow you to monitor your entire fleet, even if you are operating buses from different manufacturers or fuel Figure 9-9. Example KPI comparing lifetime fuel costs (for illustrative purposes only, values do not reflect actual deployment data). technologies. Oftentimes, these services create customizable reports, providing the data you define at the frequency you desire.

Data Monitoring and Evaluation 133 • Asset management systems and maintenance reporting systems: Your maintenance department will have information on vehicle service needs, parts and labor costs, and reasons for a bus being out of service to inform fleet availability and maintenance costs. • Operations reporting systems (e.g., TransitMaster, Clever Devices, FLEETWATCH, HASTUS): Your operations department may track data such as route and block assignments, driver assignment, driver time on/off, and route time points. Operations may also track reasons for road calls and any driver-reported issues that arise while in service. 9.5 Data Collection Procedures Designate a point or points of contact at your transit agency to maintain and evaluate the collected data. That staff will most likely be required to coordinate across departments to collect and validate the data. Some transit agencies use application programming interfaces (APIs) to automatically collect data from IT systems, translating the data into a format that can be more easily used. Otherwise, maintaining a spreadsheet is a common approach to maintain and analyze data. Developing monthly or quarterly reports is suggested; however, if you used grants to purchase ZEBs, the funding agencies may have specific reporting requirements. Determine if your management or board of directors would like regular reports on specific metrics. NREL conducts data analysis on ZEB deployments through a partnership with the FTA. NREL publishes regular public reports on bus deployment data. 9.6 Additional Resources • Third-Party Data Monitoring o Clever Devices o FLEETWATCH o GreenRoadTM o Trapeze SmartMonitor o ViriCiti • OEM Data Monitoring o BYD, in coordination with I/O Controls, Health Alert Management System (HAMS) o New Flyer Connect o Proterra APEX • GHG Emission Calculations o State Electricity Profiles, Energy Information Administration o Greenhouse Gas Equivalencies Calculator, U.S. Environmental Protection Agency o Energy’s Fuel Property Comparisons, U.S. Department of Energy

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The zero‐emission bus (ZEB) market, including Battery Electric Buses and Fuel Cell Electric Buses, has seen significant growth in recent years. ZEBs do not rely on fossil fuels for operation and have zero harmful tailpipe emissions, improving local air quality. The increase in market interest has also helped decrease product pricing.

The TRB Transit Cooperative Research Program's TCRP Research Report 219: Guidebook for Deploying Zero-Emission Transit Buses is designed to provide transit agencies with information on current best practices for ZEB deployments and lessons learned from previous deployments, industry experts, and available industry resources.

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