LEAP

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Topic: issue in electricity moduleSubscribe | Previous | Next

Dorji Yangka 6/5/2017

hi taylor,

I am enclosing herewith the following 2 pdf files for the subject matter.

1) power plant capacity details

2) module energy balance

I have used the optimization feature for the electricity module. the import cost of electricity is higher than that of export.

1) above shows erratic variations in the DG set output. to fix it I tried using both maximum and minimum variable tabs, but does not seem to work.

2) above shows that in 2015 (first year scenario), the output and export of electricity decrease whereas import increases compared to that in 2014 (base year). does this reveal that the idea of exporting huge quantity of electricity is not so desirable and cost effective, given that optimization provides optimal solution within the constraints (if specified in the model)?

thanks for your continued support

Dorji

Attachments:

module energy balance.pdf [9] ,

power plants.pdf [7]

Taylor Binnington 6/5/2017

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Hi Dorji -

I don't see any capacity data attached to your message - you attached only the module energy balance, and the result "Output by Output Fuel".

LEAP's optimization capabilities use only the processes listed in the module to satisfy module requirements. So, unless you have included a value for the "Import Target" variable (found for each module output fuel), LEAP will not import electricity into the module (no matter what the cost of imported electricity is), unless there is insufficient available capacity spread among the module's processes.

If you want to allow LEAP to choose between imports and constructing/dispatching domestic capacity based on cost, then you will need to include an explicit "imports" process within your electricity generation module. If you do this, be sure that it consumes a different type of fuel that the module's output fuel (i.e., you could create a new fuel called "Imported Electricity" in LEAP's Fuels database, and then use this new fuel as the feedstock fuel for your explicit "Imports" process inside your module), and set the Fuel Cost equal to whatever the price of imported electricity is.

I can't really comment on the variability of the "DG set" outputs without more information. There are many reasons that it could be happening. One thought that occurs to me, since there is a large change in output from 2014 to 2015, is that your historical production could be greater than the maximum availability of your power plants. LEAP will let you enter any Historical Production values that you want regardless of how much available capacity existed in 2014, but as soon as it begins dispatching in 2015, th eavailable capacity constraints will be obeyed.

Best,

Taylor

Dorji Yangka 6/7/2017

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thank you taylor for your suggestion on 'imported electricity'.

Now that I am setting an 'imported electricity', how do I correctly set the 'output properties' under the electricity module? Do I set it to 'requirement remain unmet' or 'import fuel to meet shortfall'?

I am enclosing herewith the missing attachment on the power plant output by output fuel. The enclosed table shows erractic changes for the DG set in 2030. I tried to fix it using maximum and minimum variable/tab, but the tabs/features does not seem to function.

Thanks for your time,

Dorji

Attachments:

power plants_optimized.pdf [9]

Taylor Binnington 6/13/2017

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Hi Dorji,

In your situation, since you have now explicitly incuded a process to account for electricity imports, it shouldn't matter how you set the "Shortfall Rule" for the module's output fuel. But remember that you may only set it once (in Current Accounts) for all your scenarios.

The table you attached is the same table that you attached in your earlier posting. Again, there is no way to know if the results are expected (given the contraints that you have set) or unexpected. If you wish, you may attach/send your model, together with a description of how you've tried to constrain the "DG set" generation, and what your are trying to achieve by adding these contraints.

Hope this is useful,

Taylor

Dorji Yangka 6/20/2017

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hi taylor,

thanks for your response. sorry for the delay.

in the file "output by output fuel', if you check the generation by DG sets, it changes erratically between 2025 to 2030 and 2030 to 2035. Generating from DG set does not make sense when Bhutan has lots of installed hydropower generation capacity especially when the task is to reduce emission. by putting a constraint I was trying to control the output of the DG set to be not more than the historical production.

Anyways the straight question is - can I use the min capacity and max capacity variables to control the generation from a specific power plant?

thank you for your time and support.

Dorji

Taylor Binnington 6/26/2017

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Hi Dorji -

The Minimum Capacity constraint will not necessarily guarantee that the process will be dispatched, but you may use the Maximum Capacity constraint (together with Maximum Availability) to set a limit on the *maximum* amount of generation permitted in any time slice. LEAP/OSeMOSYS still dispatches on the basis of reducing the module's NPV, and so it is possible that even if the plant's Minimum Capacity is constructed, it will be too expensive to operate - and it will sit dormant, while other power plants are dispatched instead.

There is no easy way to include a "generation"-type constraint in addition to a "capacity"-type constraint using LEAP/OSeMOSYS.

Aside: Depending on your situation, it may be possible to include a second non-optimized module above your primary electricity generation module. You could include the must-run power plants in this module, and dispatch them to meet a fixed percentage share using LEAP's basic dispatch rules. They would then have the first opportunity to meet electric load, and you would need to set the shortfall rule to "Requirements Remain Unmet", so that your primary electricity generation module can meet the rest of the requirements. But, if you go this route, you will need to decide how new capacity in this module would be constructed (using LEAP's Endogenous Capacity variable), and you may need to re-design the load curve which you assign to your primary (optimized) electricity generation module.

Taylor

Dorji Yangka 6/26/2017

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thank you taylor for your kind response.

so looks like it will be a complicated process. I think I will leave optimization for now an go with full capacity dispatch.

Under the full capacity dispatch, I hope that the model takes into consideration the availability curve assigned for the hydropower plants.

thank you,

Dorji

Taylor Binnington 6/26/2017

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Hi Dorji - yes, you can always assign a (time-sliced) Maximum Availability curve, which will be respected when LEAP dispatches plants.

Best,

Taylor