What does dummy import mean?

[huichenpku]

Hello,

    I set two kinds of coal to produce electricity to sastify the electricity demand, but I find dummy imports satisfy most of  electricity demand instead of coal. There are not any constraints for coal mining, so anyone can explain it? Attached is my simple example. uploads/271/My_2.zip

[huichenpku]

Really need your help！

[Vikrant]

Your issue will resolve if you add highlighted attribute.

[AKanudia]

By default, VEDA prohibits new investment in technologies that have a stock, by inserting NCAP_BND(UP)=2 for Year=0. This is the compact way of prohibiting new capacity creation, by specifying an interpolation option (without a seed value)

You can easily disable this by adding the declarations shown in the picture above.

Further, if you wanted to disable this feature in your entire model, you can put an INS table in BY_Trans file: Attribute=NCAP_BND; LimType=UP; Year=0, AllRegions=0,PSET_PN=*; Attrib_Cond=Stock

[huichenpku]

Thank you for your detailed explaination and useful suggestion, and it works now.

[huichenpku]

Dear AKanudia , thank you for your help again, and I have a new problem now. I don't know where to look for the values of attributes of stock and AFA in VEDABE, can you tell me how to solve it?

[fg]

Dear Supporters and Admins,

thanks for this helpful hint, the NCAP_BND~UP~0=0 helped in order to have new capacities being built.

BUT, a new problem arises. My base year is 2010 and as soon as I define a STOCK (for 2010) and additionally a STOCK~2015 the functionality is disabled again, hence no new capacity is being built anymore...

I tried:
- set NCAP_BND~UP~2015=0
- renamed STOCK~2015 into VAR_CAP~2015
- renamed it again to BNDCAP~FX~2015 / BNDCAP~LO~2015
- set the base year of the model to 2015 and added PASTI~2010...

In the end, nothing helped
How can I define a process with two supporting points, for 2010 and for 2015 and the rest is up to the optimizer?

Thanks a lot in advance for your help!
FG

[Antti-L]

I am not able to see what your problem is.

Are you saying that you get dummy imports after adding those STOCK parameters for 2010 and 2015 (even though you have set NCAP_BND~UP~0=0), but without them there are no dummy imports?

Maybe you can post a screen-shot showing all the process parameters you have defined?

[fg]

Dear Antti-L,

yep, this is exactly the problem. When I disable the STOCK~2015 like that


I have no dummy imports and new capacity is being added in the following years (of course, the 2015 values do not fit, since the column with the * is disabled). These are the results for the capacities:



However, when I activate the column (hence I take the * away from the header), the capacity for 2015 is correct but no capacity after 2015 exists at all any more. Thus, my demand is being fed by the IMPNRGZ dummy...

See here:

[Antti-L]

Thanks for confirming that your problem manifests between
the no STOCK case and the case where you have specified STOCK for 2010 and
2015.

However, your pictures about capacity development only
show the development of the STOCK (residual capacity), in the two cases where
you have defined STOCK either for 2010 only, or for both 2010 and 2015.  In the first case, the STOCK values will decay
linearly over the technical lifetime, and the picture just shows that it is working exactly
as documented. In the second case, the STOCK is interpolated between 2010 and
2015, and is zero afterwards, and the picture just demonstrates that this is
indeed the case. So, all the STOCK values develop fully as expected and documented.  But if I understood you correctly, these
STOCK differences are completely irrelevant to your problem with the dummy
imports. You don’t seem to have any new capacity in either of the two cases shown!

It might help if you would post a screen-shot showing
all the process parameters you have defined (from Basic Functions →
Browse →
TIMES View), to verify that the NCAP_BND~UP~0=0 is getting correctly
into the database.  But if the model is a
small test model, why not post the whole model here (the Excel templates), and
then it would be easy to see where the problem is.

[fg]

Dear Antti-L,

thanks a lot for you help!
Okay, I agree that it looks like I don't have any new capacity being added at all...

But I think I yet do not understand the logic behind TIMES enough: Why do the values not decay linearly over the technical lifetime in the case when both 2010 and 2015 STOCK values have been set??? I understand that TIMES interpolates between 2010 and 2015 to gain the values for 2011, that makes absolute sense to me. But why is it zero afterwards, when the technical lifetime of a powerplant is defined as some 40 years??

Moreover: What is the difference between PASTI and STOCK ? To my understanding both are used to tell TIMES that there is already capacity installed.

As you recommended, I checked in the times view whether the Attribute NCAP_BND~UP~0=0 is correctly imported and I can confirm this:


So the problem seems to be somewhere else. Attached you can find my model. Any help is greatly appreciated

uploads/291/SmallModel.zip

[Antti-L]

Regarding your questions:

STOCK is an alias for the TIMES parameter  PRC_RESID, which has the indexes  PRC_RESID(reg,y,prc). This parameter can be used for specifying the amount of existing capacity of process prc still available in year y. In other words, the idea is that with this parameter you can define the assumed phase-out of old capacity of process prc in an easy way, even though the total capacity may consist of many existing plant units that were originally installed at different times.

However, sometimes it is convenient to just assume that the old capacity would decline linearly over certain years, and therefore it was suggested by Amit Kanudia about 10 years ago, that if the existing capacity is specified for only a single data point with PRC_RESID, then we should assume a linear decay of that capacity over the NCAP_TLIFE years defined for the process.  And so, for convenience this has been implemented. You can always disable this feature by explicitly defining a zero value for the capacity in next data year.

Anyway, for power plants, you should define the phase out of old capacity yourself, and define PRC_RESID for all the model years where there is still old capacity available.  Alternatively, you can use NCAP_PASTI(reg,y,prc) for defining all the past investments of capacity of process prc at years y, where the year y refers to the installation year (i.e. when the capacity was originally commissioned).

I tested your model, and it solved well without any dummy imports.  The model invested only into the cheapest technology, Con-ELC-CHP_HEAT_NG-GT (CHP).  I notice that you are not defining any CHP parameters for the CHP technologies, but that's not a big problem while the heat demand is so small (the CHPs can now work like condensing plants...). But you don't seem to have any fuel prices..

[fg]

Dear Antti-L,

thank you, I'm gaining some more understanding of TIMES' behaviour.
Just for your notice: I have fuel prices defined, they are just in another file which I thought is irrelevant for describing what the problem is.

Well, it seems like PRC_RESID or STOCK is not the parameter I need in this case. There is only one technology that shall phase-out in pre-defined time-steps and I am using it already for this purpose.

Maybe I should describe a little bit better what I want to do with the other processes:
I want the model to begin (=calibrate) in the year 2010, since I have almost any important statistics and data for all the sectors for 2010. However, for the power sector, I already know both the installed capacities for 2010 and for 2015.
What I can do, is to filter my power plant data base by the commission years and set different values for PASTI~1950, PASTI~1955, PASTI~1960 and so on. Will do it soon.

The problem is, that both in 2010 and 2015 the sum of old capacities (defined with PASTI) and the new ones (which the model has to build) MUST match my given value from the official statistics.
Thats why I already thought I could do it somehow with boundary-conditions... Forcing the model with defining BND_CAP~FX~2010 / BND_CAP~FX~2015 to the given values, but this doesn't work, as VEDA-FE tells me that these are alien headers and therefore the whole column is ignored.

Do you maybe now better understand where my problem is? And can you tell me how to solve it?

Thanks!
Fabian

[Antti-L]

Sorry, no I don't think I understand your problem.

Why do you think that you cannot you use PRC_RESID/STOCK for defining the amount of existing capacity in 2010, 2015, ... etc.?  It is a very easy way to match the existing capacity to the statistics, e.g. in 2010 and 2015.

I also don't understand why you should match the sum of old capacity and the new ones in 2010 and 2015 to the official statistics. As far as I know, 2010 and 2015 are both history, and hence you will not have any new capacity in 2010 or 2015. And so, you can just include the known capacities fully in the PRC_RESID values, and you will immediately have a perfect match.

But of course, you could also use CAP_BND to bound the total capacity (PRC_RESID+VAR_NCAP) to a given value in 2015, if you want to allow new investments back in the history... 

[fg]

Ok, now I am confused... The problem is actually very simple ;-)

You now tell me I can use STOCK for matching the existing capacity with the statistics. This is true, but however these technologies do not phase-out when I do it. Hence, they are zero after 2015 (see the 3rd picture in my first post). This is wrong, of course there is coal, gas etc. capacities left..  I just want the installed capacities in 2010 and 2015 match my values from the statistics and see them fading out according to their given technical lifetimes in the years 2020, 2025 and so on...
And since 2010 and 2015 are indeed history, I don't want to have any new capacity in those years, but in the following, yes, if needed to fulfill my given demand.