New vehicles retirement

[mresende]

Hi, I have a model in which new vehicles are modeled as a process, with a stock that corresponds to the number of new vehicles. I have two questions:
- Is there a way to change the parameters of this process according to vehicle's age? That is, if I want to represent an AFA that is different if the car has 2 or 3 years old, how to do this?

- Is ther a way to represent that the stock decays each year, that is, vehicle retirement? For example, if the STOCK of the vehicles entering in year t is S, I want the STOCK of those vehicles (that entered in year t, not the ones that entered in year t+1) to be S*0.95.

Thank you!

[Antti-L]

If the process is vintaged, you can shape the availability factors NCAP_AF and NCAP_AFS by age.  If it is not vintaged, you can still shape NCAP_AF and NCAP_AFS(ANNUAL) by age.  NCAP_AFA can never be shaped by age, but as said, you can use NCAP_AFS(ANNUAL) instead of NCAP_AFA if you want it to be shaped.  To apply a shape, define the SHAPE index and then assign it to the process by using NCAP_AFX.

I am not quite sure what you mean by STOCK, but because under VEDA it is defined that STOCK = PRC_RESID, the answer appears simple: you can define PRC_RESID(t+1) = PRC_RESID(t)*0.95 for all t, and so your STOCK will decay each year.

[EDIT:] In case you would mean by stock the new capacity installed in each period, in the latest versions of TIMES you can also shape the capacity transfer of each new capacity vintage to the subsequent periods, by age. In that case the corresponding input parameter is NCAP_CPX, and it is used basically in the same way as NCAP_AFX. Consequently, in TIMES there are two slightly different options of changing the availability of process capacity by its age: through shaping the availability factors, and through shaping the capacity transfer coefficients.

[mresende]

I have never used any of these attributes. Are there any examples where I can find the use of NCAP_AFS/NCAP_AFX, PRC_RESID and NCAP_CPX?

Thank you a lot!

[Antti-L]

For an example of using NCAP_AFX, see here:
http://forum.kanors-emr.org/showthread.php?tid=241

Using NCAP_CPX is quite similar. Using NCAP_AFS or PRC_RESID is straightforward, just have a look at them in the VEDA-FE Attribute master.

[mresende]

Thanks a lot!