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From page 67... ... 67 PHASE 4 FUELING INFRASTRUCTURE STRATEGY AND COST 4.1 Overview Establishing a fueling strategy and estimating fuel costs is an important step to ensure that you are maximizing the utilization of your buses and infrastructure in order to minimize costs. Both BEB and FCEB deployments will require electricity for bus charging or hydrogen fueling. Read the entire page →
From page 68... ... 68 Guidebook for Deploying Zero-Emission Transit Buses 4.2 Key Stakeholder Considerations External Stakeholders • Electric utility providers should be engaged throughout the ZEB deployment process to discuss service and infrastructure needs, changes to your electricity rate schedule, and methods to lower electricity costs through demand management. The utility may be able to offer pilot rates or programs to support the ZEB deployment or infrastructure operation. Read the entire page →
From page 69... ... Fueling Infrastructure Strategy and Cost 69 4.3 Battery Electric Buses and Utility Rate Analysis Deploying BEBs may result in a significant increase in your electricity usage compared to the historical usage of your facilities. A transit agency with a full BEB fleet may be one of the largest electricity users in the utility's service area. Read the entire page →
From page 70... ... 70 Guidebook for Deploying Zero-Emission Transit Buses 4.3.2 Electric Bill Charges Electric bill charges are commonly broken down into the following categories, described in more detail below: Power Factor Working power, measured in kW, is the actual power electrical equipment requires when performing its function. For a bus charger, the working power would be approximately equivalent to the power rating of the charger (e.g., a 50 kW depot charger would have 50 kW working power) Read the entire page →
From page 71... ... Fueling Infrastructure Strategy and Cost 71 • Fixed Costs, • Energy Charges, • Demand Charges, and • Other Charges. These charges will be applied to each electric meter installed at your facility. Read the entire page →
From page 72... ... 72 Guidebook for Deploying Zero-Emission Transit Buses The following examples illustrate how peak demand is calculated based on different usage scenarios, assuming a 15-minute demand window. Note that the calculations below do not take into account efficiency losses that may result in higher demand charges. Read the entire page →
From page 73... ... Fueling Infrastructure Strategy and Cost 73 Example 2: A separately metered 450 kW fast charger is installed. Your highest demand possible for that charger would be approximately 450 kW, which would occur if your bus took 15 minutes to charge: 1 charger × 450 kW × (15 minutes of charging / 15 minute demand window) Read the entire page →
From page 74... ... 74 Guidebook for Deploying Zero-Emission Transit Buses 4.4 Typical Rate Structures Building and maintaining a strong relationship with your electric utility is vital throughout the deployment process. Some utilities have implemented rate structures and pilot programs that promote the deployment of zero-emission vehicles. Read the entire page →
From page 75... ... Fueling Infrastructure Strategy and Cost 75 expensive in the afternoon) Read the entire page →
From page 76... ... 76 Guidebook for Deploying Zero-Emission Transit Buses 4.5.1 Electricity Costs Hydrogen fueling infrastructure operates similarly to diesel and CNG fueling stations. At a minimum, hydrogen fueling requires compressors, cooling, and a dispenser, which can consume a considerable amount of energy. Read the entire page →
From page 77... ... Fueling Infrastructure Strategy and Cost 77 4.5.2 HydrogenCosts Transit agencies can either purchase hydrogen from a supplier or produce it on-site. If you are purchasing hydrogen from a supplier, the supplier and dispensing company will dictate product costs. Read the entire page →
From page 78... ... 78 Guidebook for Deploying Zero-Emission Transit Buses A rate model will provide an upper bound of costs and operational parameters for your BEB deployment. It will also help identify what factors have the greatest impact on costs, which may be managed with charging strategies. Read the entire page →
From page 79... ... Fueling Infrastructure Strategy and Cost 79 4.6.1 BEB Charging Strategy Utilizing the results of your route and rate modeling efforts, schedule data, the available battery capacity of your buses, and the power delivered from your chargers, develop a charging strategy that meets service needs while minimizing costs. On-route charging strategies can be either charge depleting or charge sustaining (as shown in the illustrative on-route charging sessions in one service day in Figure 4-3) Read the entire page →
From page 80... ... 80 Guidebook for Deploying Zero-Emission Transit Buses • Limiting the number of buses being charged simultaneously (e.g., charge 4 buses, then charge the other 4) or • Reducing the power output of your chargers (e.g., charge eight buses over the 8 hours at 60kW instead of 125kW) Read the entire page →
From page 81... ... Fueling Infrastructure Strategy and Cost 81 While operational procedures can be another strategy for minimizing demand, be sure to educate all relevant staff on charge management procedures to avoid accidental charging. Plugging in and charging buses at the wrong time, even once in a billing period, can immediately impact demand and negate the benefit of a charging strategy. Read the entire page →
From page 82... ... 82 Guidebook for Deploying Zero-Emission Transit Buses As transit resources are often part of emergency management planning , resilience and emergency response planning are an essential element of your ZEB deployment. FCEB systems require power for fueling infrastructure to operate and depend on a hydrogen supply stored, or created, on site. Read the entire page →
From page 83... ... Fueling Infrastructure Strategy and Cost 83 Table 4-1. Summary of available options for backup power. Read the entire page →
From page 84... ... 84 Guidebook for Deploying Zero-Emission Transit Buses SYSTEM NAME DESCRIPTION ADVANTAGES DISADVANTAGES Fuel Cells • Molten Carbonate Fuel Cell (MCFC) • Phosphoric Acid Fuel Cell (PAFC) Read the entire page →

From page 67...

... 67 PHASE 4 FUELING INFRASTRUCTURE STRATEGY AND COST 4.1 Overview Establishing a fueling strategy and estimating fuel costs is an important step to ensure that you are maximizing the utilization of your buses and infrastructure in order to minimize costs. Both BEB and FCEB deployments will require electricity for bus charging or hydrogen fueling.