Allow BESS to Export

[adfarth]

Added

• Allow ElectricStorage to export to the grid with input options for grid export: can_net_meter, can_wholesale, can_export_beyond_nem_limitand associated decision variable dvStorageToGrid
• Add result ElectricStorage storage_to_grid_series_kw

Fixed

• Bug in max benefit constraint for WHL export; bug allowing for both WHL and NEM to be used

TODO:

• Add BESS inputs for can_net_meter, can_wholesale, can_export_beyond_nem_limit
• index dvStorageToGrid on metering type, following the logic of tech export bins
• Determine whether to use dvs for total BESS discharge & BESStoGrid vs. BESStoLoad & BESStoGrid --> Choosing to mirror tech production by using dvDischargeFromStorage as total discharge with dvStorageToGrid
• Incorporate dvStorageToGrid into load balancing constraints
• Test outputs against expected values
• Review and update emissions calculations to account for BESS export
• Check and remove all references to "can_export_to_grid" (currently commented out)

Things to test:

• BESS has NEM and PV does not --> This is now fixed and allowed
• BESS has wholesale and PV does not --> should allow this (and test)
• All 3 new inputs for BESS
• Different solvers (with vs without indicator constraint compatibility)
• PV has NEM or WHL and BESS does not
• Make sure BESS serves load first
• Test with thermal storage
• Test solve time impacts compared to master branch (impacting solve times even without allowing BESS to export?)
• Check export in MPC -- not currently high priority so could remove if this adds a lot of work

Future work:

• Consider adding other frameworks outside of net metering or net billing. E.g. BESS can export and not receive any compensation, or can export and receives a per kWh compensation during defined periods (or other VPP/demand response compensation schemes)
• Battery can now discharge to the grid, but this export is not yet accounted for in the RE calculation. This is only relevant if include_exported_renewable_electricity_in_total = false. If false, the battery could become a "back door" for export of RE to the grid since it's not subtracted here. Will require tracking of RE in BESS.

Notes/Assumptions:

• BESS kW capacity does NOT count towards net metering limit
• ElectricStorage can end up being sized, and export, much more than the peak load (this is currently true in develop, too, but now the issue is more extreme)

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Pull request overview

Copilot reviewed 21 out of 22 changed files in this pull request and generated 9 comments.

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[lixiangk1]

I'm not sure how to add comments to files that haven't been changed, but...

• Wondering if there should be an update to results/electric_tariff.jl#L230 to consider BESS exports?
• Haven't checked MPC exports thoroughly, but may need to add dvStorageToGrid to the function at mpc/constraints.jl#L28

[adfarth]

I'm not sure how to add comments to files that haven't been changed, but...

• Wondering if there should be an update to results/electric_tariff.jl#L230 to consider BESS exports?
• Haven't checked MPC exports thoroughly, but may need to add dvStorageToGrid to the function at mpc/constraints.jl#L28

Great catch on electric_tariff.jl. I updated that to account for BESS export and fixed a bug in there.

Also updated the mpc constraint: c5a452c