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Common Questions from the Diesel Emissions Quantifier Webinar of January 29, 2009

General Questions

Q: Black carbon (aka, elemental carbon) is a potent climate change agent and is found in diesel particulate matter. Does EPA have any plans to include reductions in black carbon in the DEQ so that climate change impacts can be estimated?
A: At this time EPA does not have plans to include this in the DEQ, however, EPA is looking into it.
Q: Do you envision ever allowing C3 marine vessels to use the DEQ?
A: EPA is planning on incorporating C3 marine engines into the DEQ, but there is no date on when this component will be available at this time.
Q: Do you look at the lifetime of the emission control device in calculating lifetime benefits or just the vehicle?
A: All the calculations are based on the life remaining of the vehicle, instead of the emission control device. EPA is focused on reducing emissions from diesel engines, so once a vehicle is retrofitted, EPA believes that vehicle should stay retrofitted for its remaining life.
Q: Can this calculator be used to estimate benefits for the Congestion Mitigation and Air Quality Improvement Program (CMAQ)?
A: Yes, the DEQ is an estimation tool, so you can use it for planning purpose.
Q: Does the DEQ give results in metric tons or short tons?
A: Short tons
Q: I have some light duty projects (diesel pickups), how do I calculate their emission reductions?
A: The DEQ calculates emission reductions for heavy-duty vehicles. The National Mobile Inventory Model (NMIM) tool can calculate emission reductions for both heavy-duty and light-duty vehicles.
Q: Can we find past projects that EPA's National Clean Diesel Campaign has funded on the web site?
A: Yes. A map as well as a searchable table of 2000-2007 NCDC projects is available. The 2008 projects will be posted soon.
Q: The online SmartFinance loan application does not have Truck Stop Electrification (TSE) right now. Will it have an option for loans to truck stop owners who need money for this diesel emission solution?
A: The DEQ is not directly linked to the SmartFinance loan application.
Q: Is there any way to save more than three scenarios for a single log in account in the DEQ?
A: No, however, you can open as many accounts as you want (three scenarios for each account), you just need a unique e-mail address for each account.

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Data Entry Questions Regarding Vehicle Fleets

Q: What do you do if you have multiple vehicles that are different - do you generate a report for each one?
A: Not quite. You get one report in the download file, and you will see each vehicle as a separate line of entry.
Q: Why don’t we separately enter maintenance and operating costs?
A: These costs associated with a retrofit project are not incorporated into the DEQ.
Q: Our fleet of construction equipment varies from 2001 to 2006, so do I use one vehicle group or six?
A: You have the option of doing one group, six groups, or something in between. If the model years are close, then you can combine all the vehicles into one DEQ run. By creating one vehicle group, your results will not be as accurate as they would be by creating a separate run for each vehicle, however, in most cases, this variation is small. It is up to you to choose to do each run separately, combine into a few groups, or put all of them into one big group.
Q: When I am trying to enter my fleet information, I cannot select the model year for my fleet.
A: Depending on the type of fleet, sometimes, the DEQ assumes that only certain model years can be retrofitted. In this case, you may need to select the closest model year to your fleet and keep in mind that it will have an effect on your estimate.
Q: How does the DEQ calculate the life of the vehicle? Can that value be changed?
A: The DEQ takes into consideration the type of engine, its application, and the model year, and gives a default lifetime for each vehicle set. For on-highway vehicles, the lifetime is roughly set at 30 years; for non-road applications it will vary. Unfortunately, there's no easy way for you to change the remaining life of the vehicle.
Q: Is there a way in the DEQ to calculate baseline emissions?
A: Yes. You can just enter the fleet info and leave the technology part alone. Then select "Quantify Emissions". It will give you baseline numbers with no emission reductions.
Q: Is there a way in the DEQ to calculate replacing a diesel engine with an electric technology?
A: No.
Q: We use on-highway engines in our non-road port yard tractors. Which field should we select?
A:There are two options: Either select non-road and find the vehicle that resembles your yard tractor or else determine what type of engine it is most similar to: class 5-8a. You can then select on-highway, choose "Ports" for the sector, then under Vehicle or Equipment, select the appropriate engine.
Q: Is the baseline a reliable number? If a fleet has very old vehicles (older than 1990), then these numbers may be skewed lower.
A: The emission factors used to calculate the baseline emissions are based on data from the National Mobile Inventory Model (NMIM).
Q: What if I have vehicles in both on-road and off-road applications?
A: The DEQ can support multiple vehicle groups, including a mix of on-highway and non-road for a given scenario.
Q: What if you are doing multiple scenarios for one project? Can you still use the cost effectiveness calculation?
A: If you have multiple VEHICLE GROUPS (not scenarios) for your project, you will not be able to use total cost effectiveness calculated from the funding source; but if the multiple vehicles all relate to one project, save the vehicles under one scenario and enter the funding values only once with the first vehicle group, and leave the other vehicle fleets alone.
Q: Should I enter the usage rate for one vehicle or the whole group?
A: Usage rate and all other vehicle fleet data should be entered for just one vehicle (which should be a rough average of all the vehicles in your group). Only the Fuel Volume is entered as a total for the entire group.
Q: If off-road equipment does not have idle reduction for its technology type, how do you quantify emissions reductions if you want to put an automatic shutdown device on an off-road vehicle?
A: We suggest making the calculations with equations; help documentation is available. Feel free to send a message to Clean Diesel (cleandiesel@epa.gov) for guidance.
Q: Any plans to include stationary equipment in the DEQ?
A: Yes, stationary sources like generators and air compressors will be added in the near future.

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Data Entry Questions Regarding Fuels and Technologies

Q: How do you enter data for alternative fuel engine calculations, specifically natural gas?
A: To calculate emission reductions for a vehicle that is switching to an alternative fuel, first enter the vehicle fleet information under the "Enter New Vehicle Group Information," and save that information. Then, under the "Apply New Technology to Vehicle Group", select "Fuel Options" under "Technology Type," and select your fuel under "Technology."
Q: For marine projects, will Ultra Low Sulfur Diesel (ULSD) be included under Fuel Options?
A: Yes
Q: We are building a station for Truck Stop Electrification (TSE). Should we use the number of parking spots at the station as the number of vehicles for the fleet? What about the vehicles’ model year? As of now, we don't really know which vehicles will be using the TSE.
A: The DEQ can calculate idling emissions reduced based on the number of idling hours that are eliminated due to the use of the TSE. You will have to make some general assumptions about the trucks that will be using this TSE.
Q: Can the option Diesel Oxidation Catalyst + Closed Crankcase Ventilation (DOC+CCV) system be added as a retrofit device?
A: Yes. After entering the Vehicle Group Information, go to "Apply Technology to Vehicle Group" and choose Emission Control Devices under "Select Technology Type," and you will be able to find DOC+CCV under "Select Technology."
Q: Is there a scenario for using the DOC+CCV combination technology? How about CCV by itself?
A: Crankcase Ventilation (CCV), is one form of technology retrofit, however, it is not listed as a stand-alone technology, but it is included under "Emission Control Devices" as DOC+CCV, or DPF+CCV (Diesel Particulate Filter +CCV). If you are using CCV as a stand-alone, you can select "Other Emission Control Devices" from the "Technology" menu and enter the reduction percentages by hand.
Q: Does the quantifier also calculate emission reductions for replacements?
A: Yes. It is under Engine Replacement/Repower for "Technology Type", and Engine Replacement under "Technology."
Q: For nonroad, one may use a different fuel for the baseline than the one used for a retrofit device. How do you handle that in the DEQ?
A: The DEQ can calculate the reductions from devices as well as fuel changes. In this case, you can enter your vehicle information by using the "Enter New Vehicle Group Information". For "Select Fuel Type," put in the fuel that was used before the retrofit. Then in "Apply A New Technology to the Vehicle Group," you can apply as many technologies as you would like to the same vehicle(s). So, you can choose Fuel Options for "Technology Type" and select the fuel that the vehicle(s) would use after the retrofit. Hit save, and then you can return to the vehicle fleet and add another technology, which would be your retrofit device. Just be sure to apply the retrofit device to the vehicles that already have the new fuel type.
Q: Is there an option for combined technologies such as engine repower with DOC or DPF?
A: No, but the DEQ allows users to apply multiple technologies to one vehicle. After selecting your first technology and saving it, you can select another technology and save that to the current vehicle group you are working on by clicking on the "Save to VX" button. The X correlates to the vehicle group, i.e., 1, 2, 3, etc.
Q: In the off-road field (construction) DOC unit, cost varies depending on engine size. Will this necessitate using only one unit per group, or can we average the costs per unit?
A: You can either use one unit or average them. It depends on how you will use your data.
Q: Does the DEQ work for Truck Stop Electrification?
A: Yes. Truck Stop Electrification (TSE) is an idling control strategy, and in order to calculate emission reduction using the DEQ, you must make an estimate of the type and number of vehicles that would utilize the station. Once your vehicle fleet information had been entered, refer to "Apply a Technology to the Vehicle Group" and select “Idling Control” for Technology Type. This allows you to select TSE under the “Technology” drop-down menu. Realize that the DEQ will only allow you to select TSE for certain vehicle groups, like long haul trucks.
Q: What if the DEQ doesn’t have the same fuel blends listed that we have, like high blends of Biodiesel plus ULSD?
A: The DEQ really is just an estimate, so users are advised to select the option that gives the best representation of their real world application.
Q: Why doesn't the fuel efficiency change when I apply a DPF to a fleet?
A: Currently, the DEQ does not have that factored in.
Q: Are there default idling hours to select if this is not known for a specific vehicle group?
A: Please contact your EPA Region for an estimate of default idling hours. However, we strongly recommend that you thoroughly research the fleet you are calculating emissions for in order to use real world values.
Q: Would there be CO2 (carbon dioxide) emission reductions with an engine replacement?
A: There is a potential for CO2 reductions with an engine replacement, however, at this time the DEQ does not calculate it.
Q: Is it possible to divide Particulate Matter (PM) by 2.5 and PM 10?
A: No. The DEQ only calculates PM2.5.
Q: Why isn't SO2 (sulfur dioxide) included as one of the pollutants? It would be helpful for determining benefits for alternate fuel control options.
A: We many look into that for the future.
Q: When I looked at the DEQ a while back, the types of fleets that could be chosen did not include any vessels, such as tug boats. Will that be changed before the 2009 grant period?
A: We are in the process of adding marine engines to the DEQ for C1 and C2 vessels.
Q: What about a replacement/repower that saves a great deal of fuel? It does not appear to be in the DEQ.
A: At this time the DEQ does not calculate fuel saved as a result of a replacement/repower.

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