Decomposing Reg_obj

[MortenHoermann]

Hi,

I would like to decompose the total discounted system cost into sectors. I could use Reg_ACost for that purpose, but aggregating Reg_ACost using the Time_NPV does not match the Reg_obj exactly. Looking at previous threads on this board, I can see that Antti once stated that this is to be expected although I couldn't quite decipher the reasoning. So 2 questions:

1. Should I just use the Reg_ACost discounted by Time_NPV to decompose total discounted system costs on sectors?
2. Can anyone give me a simple explanation for why "sumproduct" of Reg_ACost and Time_NPV does not (should not) equal Reg_obj?

Thank you in advance
Morten

[Antti-L]

See this thread:
http://forum.kanors-emr.org/showthread.php?tid=578

As explained there, by default the annual costs are reported exactly at the Milestone years (i.e. the annual payments exactly at the Milestone year are reported). To reproduce the OBJ with TIME_NPV, you would of course need to have the discounted average of the payments over all the individual years in each period. By using the switches
$SET OBLONG YES
$SET ANNCOST LEV
you will have such (with the decommissioning costs of existing plants still being an exception, will be fixed in the next version).

Does that answer your question?

[MortenHoermann]

See this thread:
http://forum.kanors-emr.org/showthread.php?tid=578

As explained there, by default the annual costs are reported exactly at the Milestone years (i.e. the annual payments exactly at the Milestone year are reported). To reproduce the OBJ with TIME_NPV, you would of course need to have the discounted average of the payments over all the individual years in each period. By using the switch $SET ANNCOST LEV you can have that (with the decommissioning costs of existing plants still being an exception, will be fixed in the next version).

Does that answer your question?

Hi Antti,

It answers my question 2. Thank you for that. I previously read the post you refer to, but was still a bit uncertain about the reasoning. I think the operative word here is average of the annual payments in each of the individual years in a period. It makes sense now. 

For question 1, I see 2 options. Either use Reg_ACost and accept that it is only an approximation of total discounted system cost or use the $SET ANNCOST LEV switch.

Being new to TIMES I have no idea where to find that switch in VEDA FE? AND how will this affect my results?

Thank you
Morten

[Antti-L]

If using the ANNCOST LEV setting, it is advisable to use both of these two:
$SET OBLONG YES
$SET ANNCOST LEV

The first one is available in the Control Panel (see the top part).
About the second, I don't know. I hope the Kanors staff can answer that.
But you can always add it to the RUN template manually.

$SET OBLONG YES changes the objective function formulation, correcting a few inconsistencies, and so it is in fact always recommended if using OBJ= STD, MOD or AUTO.
$SET ANNCOST LEV does not change the model formulation or results at all. Only the reporting of annual cost, as explained.

[MortenHoermann]

If using the ANNCOST LEV setting, it is advisable to use both of these two:
$SET OBLONG YES
$SET ANNCOST LEV

The first one is available in the Control Panel (see the top part).
About the second, I don't know. I hope the Kanors staff can answer that.  
But you can always add it to the RUN template manually.

$SET OBLONG YES changes the objective function formulation, correcting a few inconsistencies, and so it is in fact always recommended if using OBJ= STD, MOD or AUTO.
$SET ANNCOST LEV does not change the model formulation or results at all. Only the reporting of annual cost, as explained.

Thats great Antti! Thank you for the swift reply. Now I just hope that one of the Kanors staff can fill in the last blank about the $SET ANNCOST LEV switch.

Cheers
Morten

[vangelis]

Hi Antti,

I noticed that with $SET ANNCOST LEV (together with $SET OBLONG YES) the cost component Cost_Dec (the decommissioning cost) is not reported anymore.

Here are the switches I have, regarding the discounting of the costs and the formulation of the objective function:
$ SET OBJ AUTO
$ SET MID_YEAR YES
$ SET OBLONG YES
$SET ANNCOST LEV

Do I miss a switch or do I misuse a switch and I do not get a separate component Cost_Dec for the decommissioning costs in my output? Or, when ANNCOST LEV is enabled the decommissioning costs are reported within another cost component?

Best regards,
Vangelis

[Antti-L]

Yes, when using $SET ANNCOST LEV, the levelized annual decommissioning costs are included in the levelized annual investment cost component Cost_Inv.

I think it might be rather confusing to many users to see decommissioning costs reported already while the plant has just been started operation, and that's why they are aggregated together. So, it is so for the convenience of the users (if not also for maintainers), and one can say it is also in accordance with the non-existent design for the feature. 

[vangelis]

Hi Antti,

Thanks a lot for the clarification 

Best regards,
Vangelis