Some questions in transport sector

[AKomatsu999]

Dear all,
I recently have started using GCAM for transport sector analysis and have some questions.
( I'm using GCAM 7.0 and standard modelinterface )

1. By running the default scenario (configulation.xml), "transport service output by tech and vintage" query shows zero sales in South America_Northern - trn_pass_road_LDV_4W in 2020 and 2025. Also survival rate of sales in 2015 apparently differs from other techs. It seems no calibration or share weight restrictions in transportation_UCD_CORE.xml.
   Is it a problem of gcam-core or setting values, otherwise intentional outputs?

2. I understand transportation_UCD_CORE.xml (or similar xmls) stores actual values used in GCAM calculation and only "input-cost" is available. Is there any more information to understand "input-cost" such as VKT, CAPEX, OPEX?

3. input/gcamdata/inst/extdata/energy/UCD_trn_data_CORE.csv seems the one I want. However I am wondering the relationship of these two files. transportation_UCD_CORE.xml is strictty made from .csv data with conversion of region and sizeclass, or .csv is just a reference or settings used in older GCAM?

4. Is it correct that "cost of transport techs" query shows the cost including fuel cost and CO2 price calculated in GCAM?

[pkyle]

Apologies for the delay it has taken for us to reply to this.
The issue you are seeing is that that model region, South America_Northern, consists of Venezuela and the three small countries to its east. Venezuela generally has negative GDP growth from 2015 to ~2030, so its behavior in a lot of sectors is very different from most regions. The structural equations used in the transportation sector were not designed around regions with negative GDP growth from period to period. They might return reasonable results; I'm just not sure. In any case what is happening is that the demand for transportation services is going down, so the cohort of vehicles on the road in 2015 is supplying all of the service demands of the subsequent decade. The exogenous survival curve which is normally applied to a cohort may even be getting modified, in order to reduce the service output.
The variables read to the model, and copied in the model's output, are themselves derived from more granular input assumptions about vehicle capital and operating costs. The base transportation database is UCD_trn_data_CORE.csv, with supplemental data and replacement data found in OTAQ_trn_data_EMF37.csv. Here you will find assumptions such as vehicle purchase price, assumed annual vehicle kilometers traveled per year, and others.
The translation from the input data tables inst/extdata/energy/*.csv and the XML files involves a number of processing steps. It is a rare variable that will have the same exact numerical value in each place. I think load factors of selected modes like ships and airplanes have no conversions. Cost assumptions are levelized to a per-vkm basis, and have a dollar year conversion. Energy intensities have unit conversions. All variables have regional aggregations; the input CSV tables provide the information for 15 global regions, which in the processing are downscaled to ~200 countries prior to aggregating to the 32 GCAM regions.
cost of transport techs does return the total technology cost, including fuel and emissions penalties. Just as a warning, any queries of the non-energy cost will be 1990$ per vehicle kilometer. Their unit is misreported in the output database as 1990$/pass-km or 1990$/tonne-km. Again this only applies to the non-energy costs. Total technology costs have the units reported correctly.

[AKomatsu999]

Thank you for kind and detailed reply! My doubts have been cleaned up perfectly.