Using marginal value of last used parameter as output

[Lens2021]

Hi everybody,

I've got quite a problem with modelling an electricity market where I want to set the hourly price output to the largest value used.
Short explanation of the problem:

I've got a set
PP /lig,coal,CCGT, GT/
and a price for each PP defined as a parameter (MWh_Price)
as well as a parameter Capacity(PP)

To meet demand per hour (which is an input parameter as well) we would always use the cheapest technology (PP) until its max. capacity and then the next cheapest one and so on.
Now the price per hour for the market would result from the most expensive Technology (PP) used in that hour.

The amount produced per hour per plant is defined by the variable x(PP,T) in GAMS.

Now I want to somehow display the price per hour, that a consumer would pay. I thought that it might be the marginal value of x, so x.m but it did always give me too high values. I just want to display the MWh_price I defined as a parameter in the beginning for the last technology used.


I hope someone can understand my problem and might have an Idea for a solution. I would be very happy to hear from you

Thanks in advance!!!

[bussieck]

If you want to know the price of energy, you need to look at the dual price of the electricity demand constraint. This dual price of this one tell you the change in objective if the right-hand-side (usually the demand) increases by one, that's the price the market is willing to pay for the next kWh/MWh/...

-Michael