Topic: Capacity addition and dispatchabilitySubscribe | Previous | Next
Maria Sahakyan 6/26/2016
59 Views Hello.
I will really appriciate, if you help me with the following:
I have a question regarding LEAP constraints. Is there a possibility to set constraint on one electricity generation process (in this case solar photovoltaic, as it is non-dispatchable), that the output by that source cannot exceed 20% of total electricity output.
And another question, how can we define the dispatchability in LEAP model, so that the model understands that the source is non dispatchable and no need to add capacity every year, despite the capital cost of it is cheap.
Thanks
Taylor Binnington 7/1/2016
56 Views Hi Maria,
Have you enabled optimization for your electricity generation module? My answer below assumes that you have (I'm assuming this based on your previous forums message, but please in future be sure to include all of this relevant information when you create a new thread).
LEAP does not directly support the generation constraint that you describe. Instead, you may constrain the total amount of installed capacity in any year using the Maximum Capacity constraint (ensuring that only sufficient capacity is available to meet a fixed generation target):
http://www.energycommunity.org/WebHelpPro/Transformation/Maximum_Capacity.htm
...and/or you may constrain the annual addition of new capacity in any year, using the Maximum Capacity Addition:
http://www.energycommunity.org/WebHelpPro/Transformation/Maximum_Capacity_Addition.htm
One additional idea comes to mind which allows you to constrain the electricity generation for a process, but it requires using LEAP's functionality in a way for which it wasn't designed - by using an emission constraint.
1) Define a new environmental effect by opening the Effects window (top of LEAP's toolbar) and choosing the green "+". Title the effect "MaxSolar" and assign it to the category "Other effects".
2) In Basic Params, enable "Complex Effects" in the Scope & Scale tab by checking the box.
3) Also in Basic Params, check "Enable Emissions Constraints" in the Optimization tab.
4) Add a new environmental effect to the "Solar" Feedstock Fuel which appears underneath your solar electricity generation process, in your optimized transformation module. Choose the effect you just created, "MaxSolar".
5) In the units for the newly added Environmental Loading, choose Kilogramme per Gigawatt-Hour, and "Per unit energy produced" from the Method selector. Enter a value "1" in the Expression for the Environmental Loading.
6) Under the Effects folder in the tree (directly beneath Key Assumptions) add a new branch for the MaxSolar loading. In the Annual Emission Constraint for that variable, change the units to Kilogramme.
You should now be able to add an "emission constraint" (in kilogrammes) which corresponds exactly to the maximum number of GWh which your solar process may generate in any year. Unfortunately it is not expressed as a *percentage* of annual electricity generated, but by experimenting a bit you should be able to determine an appropriate maximum absolute GWh from solar that you wish to permit in any year.
Hope this helps,
Taylor