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137 determination of loading patterns (to calculate payload), Facility freight activity, and emission factors, as is the calculation of This application calculates freight emissions from freight fuel consumption (if emissions are calculated from fuel con- facilities including truck terminals, railyards, marine and sumption) and emissions. The spatial and temporal alloca- tion of emissions is not relevant for this type of application inland ports, and airports. Supply chain design is not rele- because the input parameters do not offer the appropriate vant because the application does not intend to model a spe- level of detail to support dispersion modeling. cific supply chain. Node characterization is possibly one of the most important processes given that the analysis is asso- ciated with a node itself. Link characterization can be used if Freight Corridor the system boundaries associated with the analysis include This application calculates freight emissions from a trans- surrounding transportation links (or if links within the facil- portation corridor, which can fall within one jurisdiction ity can be identified). The determination of service levels is (state), or cross multiple jurisdictional boundaries. Supply not relevant to this application because mode choice is more chain design is not relevant because the application does not a function of infrastructure availability. If freight activity is intend to model a specific supply chain. Link and node charac- determined from commodity flows, the processes regarding terization are critical because links and nodes along a corridor commodity flows, service level, and mode choice are relevant can have unique characteristics in terms of capacity, traffic vol- to this application. Route choice is generally not relevant umes, congestion levels, and grade. Because freight activity can because the analysis is done at a facility level. As in other be determined from commodity flows, the processes regarding applications, the subsequent processes are required, includ- commodity flows, mode choice, and route choice are all rele- ing equipment configuration, freight activity, and emission vant to this application. The determination of service levels factors, as is the calculation of fuel consumption (if emis- also can be relevant because of the logistics requirements from sions are calculated from fuel consumption) and emissions. different commodity types (e.g., higher-value commodities Spatial and temporal allocation of emissions can be relevant demand faster transit times). As in other applications, the for this type of application because the input parameters can subsequent processes are required, including equipment con- offer the appropriate level of detail to support dispersion figuration, determination of loading patterns (to calculate pay- modeling. load), freight activity, and emission factors, as is the calculation of fuel consumption (if emissions are calculated from fuel con- Supply Chain sumption) and emissions. The spatial and temporal allocation of emissions is not relevant for this type of application because This application calculates the emissions associated with a the input parameters do not offer the appropriate level of detail specific supply chain. Supply chain design is required to deter- to support dispersion modeling. mine the location of the relevant facilities involved in the sup- ply chain. The level of link and node characterization will need to be commensurate with the level of detail and accuracy Metropolitan required by the analysis. Because freight activity will be deter- This application calculates freight emissions inventories mined from commodity flows, the processes regarding com- within a metropolitan region. Supply chain design is not rel- modity flows, service levels, mode choice, and route choice evant because the application does not intend to model a are required. All of the subsequent processes are necessary, specific supply chain. Link and node characterization are including equipment configuration, determination of loading important because links and nodes within a metropolitan patterns (to calculate payload), freight activity, and emission region can have unique characteristics that affect emis- factors, as is calculation of fuel consumption (if emissions are sions. Because vehicle activity is provided as an external input calculated from fuel consumption) and emissions. The spatial parameter, the processes regarding commodity flows, service and temporal allocation of emissions is not relevant for this level, mode choice, route choice, and loading patterns are not type of application because the effects of an individual supply relevant to this application. As in other applications, the sub- chain are not likely to have significant local impacts. sequent processes are required, including equipment con- figuration, freight activity, and emission factors, as is the 4.4 Case Study calculation of fuel consumption (if emissions are calculated from fuel consumption) and emissions. Spatial and temporal This section presents a case study that illustrates a possible allocation of emissions can be relevant for this type of appli- application of the Conceptual Model. The case study involves cation because the input parameters can offer the appropriate the comparison of different supply chain configurations for level of detail to support dispersion modeling. importing products from Asia to Chicago.

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138 Many product supply chains--from automotive to retail-- delivery patterns, equipment characteristics, and timeframe. rely on imports of parts or finished products from Asia. These Outputs from this analysis include freight emissions associ- shipments are typically consolidated before reaching an Asian ated with the transportation necessary to manufacture and outbound marine port, then shipped to an inbound marine distribute product X under different scenarios in each of port in North America. Most ocean containers are then either the three supply chains. All objects described in Exhibit 4-7 transloaded directly onto double-stack trains, or deconsoli- will be used in this analysis. The following sections define the dated at transloading facilities, where shipments are trans- processes required for this analysis. ferred to trucks for final delivery. In this specific case study, the goal is to quantify emissions Supply Chain Design associated with transporting 100 lbs of product X from Shanghai to Chicago via three supply chains: ocean/rail via Users need to define the logistics facilities involved in a Long Beach, ocean/truck via Seattle, and ocean/rail via Prince product supply chain, as well as the product flows between Rupert, BC. Other objectives of the analysis are as follows to: these facilities. In this case study, the following supply chains will be considered: Assist in incorporating emissions in the planning and oper- ations of logistics activities, Shanghai to Chicago via Long Beach, with double-stack Identify which parameters are responsible for changes in intermodal service from Los Angeles to Chicago; emission outputs (e.g., facility location, mode choice, route Shanghai to Chicago via Seattle, with trucking service from choice, equipment configuration), Seattle to Chicago; and Track trends in freight emissions over time, and Shanghai to Chicago via Port of Prince Rupert, with double- Compare company performance against best-in-class stack intermodal service from Port of Prince Rupert (PPR) through a benchmarking analysis. to Chicago. The most likely audience for this type of analysis will be Exhibit 4-14 illustrates the logistics facilities (nodes) and the manufacturers sourcing raw materials, parts, or finished prod- product flows between facilities. ucts from Asia. The results of the analysis are likely to be one For freight transportation demand, it can be assumed that of the criteria for designing or modifying a supply chain, given calculations will be based on a product that weighs 100 lbs and that other considerations such as economics and reliability weighs out. It also will be assumed that the user has enough also need to be taken into account. volume to fill an entire ocean container. Input parameters include facility location, shipment charac- Because the functional unit for this analysis is one product teristics, mode choice, route choice, inventory levels, packaging, and the modes are already pre-selected, the processes for deter- Exhibit 4-14. Logistics facilities and flows by supply chain. Supply Logistics Facilities/Nodes Product Flows Chain Long Beach Port of Shanghai Port of Shanghai to POLB (ocean) Port of Long Beach (POLB) POLB to intermodal facility in Los Angeles (rail) Intermodal facility in Los Angeles Intermodal facility in Los Angeles to intermodal facility in Chicago (rail) Intermodal facility in Chicago Seattle Port of Shanghai Port of Shanghai to Port of Seattle (ocean) Port of Seattle Port of Seattle to trucking distribution Trucking distribution center center in Seattle (drayage truck) in Seattle Trucking distribution center in Seattle Trucking distribution center to trucking distribution center in in Chicago Chicago (long-distance truck) PPR Port of Shanghai Port of Shanghai to PPR (ocean) Port of Prince Rupert (PPR) PPR to intermodal facility in Chicago (rail) Intermodal facility in Chicago

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139 mination of commodity flows, determination of service level, ken down depending on the ships' activity profiles: cruise, and mode choice are not required for this analysis. speed reduction zones, and maneuvering (hotelling emis- sions should be associated with a node). Truck and rail routes can be subdivided into multiple links, if detailed informa- Node Characterization tion about capacity, grade, average speed, and congestion Nodes represent freight facilities, including trucking ter- level are available. All links need to be characterized as out- minals, railyards, and marine/inland ports. The Exhibit 4-15 lined in Exhibit 4-9. characterizes all nodes included in this analysis. For the sim- plest analysis, all nodes can be characterized as freight facilities Equipment Configuration (i.e., no virtual nodes). However, virtual nodes can be used to separate links on the same route with different activity profiles This process consists of the determination of equipment (e.g., road grade, rail grade, congestion levels). Nodes will not characteristics for all routes included in this analysis. The fol- be characterized in terms of equipment availability (due to lack lowing equipment types should be characterized based on the of detailed information from a shipper's perspective) and geo- parameters included in Exhibit 4-10: OGVs, double-stack graphic area (because shippers are not interested in that type of trains, drayage trucks, and long-distance trucks. Depending information). on the level of sophistication of the analysis, users can either rely on industry defaults for vehicles or they can customize to the specific vehicles they utilize. For example, if a firm is a Link Characterization SmartWay partner, they might choose to configure a long- A link is a transportation facility connecting two nodes. In distance truck that has a better-than-average rating for fuel this analysis, the links considered will be the following: efficiency due to the use of aerodynamic devices. Ocean routes from the Port of Shanghai to the ports of Long Determination of Loading Patterns Beach, Seattle, and Prince Rupert; Alameda (rail) corridor between the Port of Long Beach to The main importance of this process is to determine the a rail intermodal terminal in downtown Los Angeles; payload associated with each type of equipment on each link. Rail corridor between a rail intermodal terminal in down- This will determine the share of vehicle emissions that need to town Los Angeles to a rail intermodal terminal in Chicago; be allocated to the product. Because the product in question Rail corridor between PPR and a rail intermodal terminal weighs out, the equipment utilization (payload as a share of in Chicago; total weight capacity) needs to be determined. For example, Truck corridor between the Port of Seattle and a trucking if the capacity of a truck trailer is 80,000 lbs, the user can distribution center in Chicago; assume that a truck would carry 72,000 lbs (i.e., 90% utiliza- Truck corridor between trucking distribution centers in tion), and that 1/720 of total vehicle emissions would be allo- Seattle and Chicago. cated to a product that weighs 100 lbs. Depending on the level of detail required for the analysis, Determination of Freight Activity these corridors can be broken down in multiple sublinks to reflect different operational characteristics of different ocean, Freight activity can be calculated separately by scenario, rail, and road sections. For example, ocean routes can be bro- mode, activity profile, transportation equipment, link/node, Exhibit 4-15. Parameters for node characterization. Link Mode Equipment Geographic Node Connectivity Availability Availability Area Port of Shanghai (POS) SEA, PPR, LBE Ocean, truck, rail N/A N/A Port of Long Beach (LBE) POS, LA_INT Ocean, truck, rail N/A N/A Port of Prince Rupert (PPR) CHI_INT Ocean, rail N/A N/A Intermodal facility in Los Angeles (LA_INT) LBE, CHI_INT Rail, truck N/A N/A Intermodal facility in Chicago (CHI_INT) PPR, LA_INT Rail, truck N/A N/A Trucking distribution terminal in Seattle (SEA_TRK) SEA, CHI_TRK Truck N/A N/A Trucking distribution terminal in Chicago (CHI_TRK) SEA_TRK Truck N/A N/A

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140 and time period. The specific formulas that will be used to cal- simplest analysis, a user can rely on default emission factors by culate freight activity will depend on the type of analysis and mode independently of the vehicle activity profile. For exam- the exact input parameters. The following provide some exam- ple, a single emission factor can be used for an entire ocean, ples of calculations of freight activity at the link level. rail, or truck route. For more sophisticated analyses, emission factors can be determined separately by transportation equip- Intermodal rail service: rail activity can be initially measured ment, activity profile, and link. For example, different emission in ton-miles of revenue freight and then converted into fuel factors will be determined for different ship types for the fol- consumption. In this example, the product weighs 100 lbs, lowing operational modes: cruise, reduced speed zone, maneu- the rail link is 50 miles long, and rail activity will be equal to ver, and hotelling. 100 50/2000 = 2.5 ton-miles. Rail activity in ton-miles will be divided by a fuel efficiency factor (ton-miles/gallons) that Calculation of Emissions is representative of the rail link and equipment in question to determine the fuel consumption allocated to the product As previously indicated, freight emissions are generally the on that specific link. In this example, the fuel consumed to product of freight activity (e.g., fuel consumed, energy gener- transport this load on this link will be 2.5 ton-miles/400 ton- ated, or VMT), and emission factors (in grams of pollutant per miles/gallons = 0.00625 gallons. measure of freight activity). Emissions will be calculated for each pollutant, scenario, mode, link/node, and time period, as COM SCE, MOD,PRO,EQP,LNK,TIM shown previously in Equations 27 and 28. Link _ LengthLNK This analysis does not involve the spatial or temporal alloca- ACTSCE, MOD,PRO,EQP,LNK,TIM = Fuel _ Efficiency EQP,PRO,LNK tion of emissions. (Equation 35) Model Calibration Drayage and long-distance trucks: truck activity can be measured in VMT on each link allocated to the specific It is possible that the user might have information from car- product. For example, if a product weighs 100 lbs, the link riers (on fuel consumption, for example), which will enable the is 50 miles long, and the amount that can be loaded onto a application of user-specific fuel efficiency factors instead of truck is 72,000 lbs (90% of 80,000 lbs), the VMT allocated model defaults. to this product on this link will be 100 lbs 50 miles/ 72,000 lbs/vehicle = 0.0694 VMT. Analysis of Scenarios COM SCE, MOD,PRO,EQP,LNK,TIM Scenarios can be differentiated based on any parameter in Link _ LengthLNK the model. For example, freight emissions can be evaluated ACTSCE, MOD,PRO,EQP,LNK,TIM = PaySCE, MOD,EQP over time to examine emission changes based on changes in (Equ uation 36) facility locations, production outputs, and service levels, as well as mode choice and/or equipment decisions. Sensitivity Since empty equipment activity will affect emissions, they analyses can be performed to evaluate the effects of given will also need to be included and allocated to the load. parameters on emissions, and this can assist users in their decision-making process. The emissions associated with a mode in one scenario are Determination of Emission Factor calculated as shown previously in Equation 31. Subsequently, The determination of emission factors needs to be commen- total emissions associated with one scenario are calculated as surate with the level of detail required by the analysis. In the shown previously in Equation 32.