Veda2.0 Released!


EQ_CombalM = 0 when ACT_BND~FX is used
#1
Photo 
Hi, I recently came across a rather strange observation and I wanted to make sure that everything is fine.


If the activity of a process (ACT_BND) to produce a commodity such as natural gas is set to a fixed value for a certain time (e.g., ACT_BND~2014~FX). The corresponding shadow prices of those commodities (EQ_CombalM) will be reported as zero in those years for those commodities by VEDA_BE.

Is this okay since we know it is an equality constraint and the corresponding shadow price can be any value? 
The reported values by VEDA_BE is attached as an image. In here, we fixed the data for 2014, 2015, and 2016 for natural gas and natural gas used in the power sector as they are available.


Thanks


Attached Files Thumbnail(s)
   
Reply
#2
Having maintained TIMES, I assure you that when TIMES calculates the reporting parameters EQ_CombalM for the shadow prices (commodity balance marginal), any ACT_BNDs have no impact on that reporting.  Thus, if the solver reports a non-zero dual value for EQ_COMBAL equation, it will be reported by TIMES and will show up non-zero in VEDA-BE. Therefore, I think that in your case the commodity balance marginals are indeed zero.

I can also see from your attached image that the commodity balance level of EQ_COMBAL is non-zero, which means that production is greater than consumption, and so the value of GAS is zero.  If you have a GAS surplus in your system, why not add an export process for GAS, and then have a value for it?  Or is the GAS really getting wasted in reality (by flaring or leaking the methane)?
Reply
#3
(31-01-2019, 02:24 PM)Antti-L Wrote: Having maintained TIMES, I assure you that when TIMES calculates the reporting parameters EQ_CombalM for the shadow prices (commodity balance marginal), any ACT_BNDs have no impact on that reporting.  Thus, if the solver reports a non-zero dual value for EQ_COMBAL equation, it will be reported by TIMES and will show up non-zero in VEDA-BE. Therefore, I think that in your case the commodity balance marginals are indeed zero.

I can also see from your attached image that the commodity balance level of EQ_COMBAL is non-zero, which means that production is greater than consumption, and so the value of GAS is zero.  If you have a GAS surplus in your system, why not add an export process for GAS, and then have a value for it?  Or is the GAS really getting wasted in reality (by flaring or leaking the methane)?

Thank you, therefore there is no problem. 
I am trying to model a type of subsidy that imports natural gas with a higher price and sells it with a lower price to different sectors (residential, industry, power, etc.). The way that I managed this issue is to attach a negative cost to that transformation process GAS-> ELCGAS (the difference between buying and selling prices). However, doing this will encourage solver to transform the rest of untouched gas to be converted to these commodities (ELCGAS). Therefore I put an upper-bound which is available historically on these processes. 

Thus, I can make these upper-bounds a little lower than actual usages and it will give a positive value as the shadow price. I think I understood this.
Thanks again
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)