Levelized Price of Resource Metric in HERON

[GabrielSoto-INL]

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Pull Request Description

What issue does this change request address?

300

What are the significant changes in functionality due to this change request?

HERON now allows users to select Levelized Cost as a metric calculated in the inner optimization step. Can be selected as an optimization metric in opt mode or an economic metric in sweep mode.

• Levelized Cost is calculated via TEAL's NPV_search metric
  • this solves for a multiplier on a cashflow price which results in NPV equal to some target
  • if the target NPV is 0 (the default), the resulting multiplier is the break-even or levelized cost
    • Users can specify a nonzero target if desired, but would result in something different from "levelized cost"
  • Users can set the base price of the cashflow to 1 (default) or have an additional ValuedParam as the price, like an ARMA or fixed value
    • in this case, the result is strictly a multiplier on the cashflow price and is NOT intended to be a levelized cost

How to use it? Depends whether a user is running an optimization or a sweep.

• If optimizing (note that the target parameter is optional):

  <Case>
    <mode>opt</mode>
    ...
    <optimization_settings>
       <opt_metric target='0'>LC</opt_metric>
       <stats_metric>expectedValue</stats_metric>
    </optimization_settings>
    ...
  </Case>

• If running a sweep (note that the target parameter is optional):

  <Case>
    <mode>sweep</mode>
    ...
    <economics>
       <EconMetrics>
           <LC target='0'></LC>
       </EconMetrics >
    </economics>
    ...
  </Case>

• User must also specify which cashflow contains the levelized cost

  • applied as a node within the <reference_price> node, replacing a ValuedParam entry

    <CashFlow>
     ...
     <reference_price>
        <levelized_cost/>
     </reference_price>
     ...
    </CashFlow>

  • currently NOT available (but coming soon) for:
    • One-Time cash flows (e.g., CAPEX)
    • Cashflows with variable ValuedParam as Drivers (e.g., a capacity variable that is optimized in the outer RAVEN step)
  • NOTE: mult_target parameter is now deprecated

• Levelized Cost requires a different inner objective function that is automatically applied. It is nonlinear, so Levelized Cost only works currently with the IPOPT solver

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For Change Control Board: Change Request Review

The following review must be completed by an authorized member of the Change Control Board.

• [x] 1. Review all computer code.
• [x] 2. If any changes occur to the input syntax, there must be an accompanying change to the user manual and xsd schema. If the input syntax change deprecates existing input files, a conversion script needs to be added (see Conversion Scripts).
• [x] 3. Make sure the Python code and commenting standards are respected (camelBack, etc.) - See on the wiki for details.
• [x] 4. Automated Tests should pass.
• [x] 5. If significant functionality is added, there must be tests added to check this. Tests should cover all possible options. Multiple short tests are preferred over one large tes.
• [x] 6. If the change modifies or adds a requirement or a requirement based test case, the Change Control Board's Chair or designee also needs to approve the change. The requirements and the requirements test shall be in sync.
• [x] 7. The merge request must reference an issue. If the issue is closed, the issue close checklist shall be done.
• [x] 8. If an analytic test is changed/added, the the analytic documentation must be updated/added.
• [x] 9. If any test used as a basis for documentation examples have been changed, the associated documentation must be reviewed and assured the text matches the example.

[PaulTalbot-INL]

Looks like we don't get ipopt on the Windows computer; however, it looks like we're requesting it as part of the dependencies, so that's odd.

[PaulTalbot-INL]

This looks like it makes progress towards #300 without completing it, so I did not mark it for closure. Let me know if I'm wrong about that!

Otherwise LGTM, tests pass, merging. If you want to announce this feature (and its limitations) on the discussion board, that would be great!