Topic: Rail vs Road using Stock Turnover methodSubscribe | Previous | Next
Ange Hartshorne 11/16/2015
676 Views 1. Has anyone used the Stock Turnover method to compare emission reduction scenarios including both road and rail fleets? At the moment it is looking to me as if I will have to treat the two fleets as a combined fleet of all the road technology and rail technology branches in together.
If I try to create category branches higher up the tree to separate Rail Transport from Road Transport LEAP seems to assume that I am then doing an energy intensity analysis (rather than using the Stock Turnover method) & won't let me enter Stock Turnover technology branches or to enter base year stock amounts under Current Accounts.
Any thoughts/comments??
2. If I have the Road Transport branches as Stock Turnover Technology branches, can I then put the Rail branches in as Energy Intensity branches within the same demand tree or will this be trying to work with apples & oranges together?
3. So, I suppose what I am trying to say is a) can you do/use both Stock Turnover Analyses and Energy Intensity Analyses within the one LEAP model/study/Demand Tree? And,
b)if you can't, then has anyone included both rail and road together in a Stock Turnover Analysis(STA)?
or
c) is it better for me to do a separate STA for the Road fleet and then an EIA (or a GHG mitigation analysis?)for the two fleets compared?
4. :) Yes, the scenarios that I want to model are policy changes that include the following two things happening in varying amounts:
1) increases of EVs into the road fleet - across all the branch categories eg including trucks as well - but varying amounts of increase for each category over time and
2) moving more heavy freight off the road and onto rail (which is largely electric or electric hybrid in this country).
Bt "varying amounts" I mean eg that some scenarios have no increase of freight to rail & some scenarios have both increased EV penetration into the road fleet and an increase of freight onto rail happening together.
5. Demand Tree structure attached as it is at present. All the road fleet branches have got the fuel tech STO branches under them -I just thought it would take up too much space to open it out completely for this so have just opened trucks for this attachment.
Taylor Binnington 11/17/2015
672 Views Hi Ange,
1. You may find it more appropriate to specify "bottom-up" stock and sales data for your transport technologies. This is a setting under Basic Params: Stocks which enables you to unselect "Top-down sales and stock data", so that you can specify each of these numbers by technology. For more info, have a quick look here:
http://www.energycommunity.org/WebHelpPro/Demand/Stocks.htm
Also, for context: when you conduct a "top-down" analysis, the stock and sales among all transport technologies are specified at the top level "Demand" branch. Even if the Activity Level variable is visible for some of your category branches, it is not used in the calculation of energy demand for transport technologies.
2. Yes, you can mix demand branch types in your tree. The only restriction is that you cannot use different branch types immediately adjacent to one another (in fact, LEAP will prevent you from doing this).
3. Yes. See above.
4. Have you considered doing a more basic activity analysis? For fuel-switching or mode-shifting targets, sometimes this approach is simplest since it allows you to easily control the shares of technologies or fuels in any given year. Put another way: what types of results do you require, that necessitate using the stock turnover methodology?
Hope this helps,
Taylor
Ange Hartshorne 11/17/2015
648 Views Thank you. I'm contemplating doing both forms of analysis in case there's useful/thought provoking info from both. If I've got enough vintage data available :)
Another allied question which might be quite dumb (but never a dumb question etc ?):
In training ex 5.2, cars & SUV vintages are combined for the lifecycle profile ie one profile is done to cover the whole lot/both categories - is it possible to do separate lifecycle profiles for each vehicle category? eg light passenger, buses, heavy freight etc. I have data for each separate category.
Or, is this what you are saying about using the bottom up approach rather than the top-down sales? That you can separate the branches out easier at the lower levels if use the bottom up approach?
Ange H
Taylor Binnington 11/20/2015
645 Views Hi Ange,
The Stock Vintage Profile is assigned for each technology (i.e. each black tire icon) separately. You're free to create as many lifecycle profiles as you like, and assign different ones to different technologies as appropriate.
Taylor
Junling Liu 6/22/2016
78 Views Hi Taylor,
I've confronted the similar problem as described by Ange about combining both "stock turnover method" and "Energy intensity" methods under the same Transportation branch.
Under transportation branch, I want to set sub-branches for "road, Rail, Navigation and Aviation". For road module, "stock turnover method" with top-down stock and sale shares will be used since more detailed information about stocks, sales, miles traveled, fuel economy of different types of vehicles (such as private cars, taxi, etc.) are available (but not by fuel types, therefore a top-down stock and sale shares method is needed here). For other modes eg Navigation, energy consumption will be calculated based on tkm and energy intensity per tkm. So a category with energy intensity is chosen for the mode.
However, when combining the two methods together under the same transportation branch. There is no stock input variable for road at any level of branches (even the top Demand branch). So I'm wondering if it is the case when we combine the two methods under the same branch? If not, is there anything wrong about my transport model? If it is the case, should I separately model road and other modes under two different branches?
Please see the screenshot of the tree structure of my transportation sector in attachment.
Looking forward to your reply.
Emily Ghosh 6/24/2016
74 Views Hi Junling,
Thanks for your question. To show the missing stock and sales input tabs, select any one of the Transport Technology branches (such as gasoline), right-click the branch and open the Properties dialog box and then click OK. This should refresh the model and you should now be able to see the variables.
Hopefully this helps!
Emily
Junling Liu 6/24/2016