Time series energy and demand charges for LCOE calcs #652
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…in bill at each timestep
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I ran the ssc tests on this branch last night and got the following results: @mjprilliman any idea if those are happening on |
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I'm probably not the best person to review the specifics of the financials but the overall structure seems to work for what I need in the parasitic cost calculations in the financial models.
Quick clarification question: does the financial model need to know which billing option was used in the utility bill calculations or can the hourly time series be used in the same way regardless?
I can account for the monthly credits on this branch
The hourly time series should be useable the same way regardless. My one qualm is the effect on the cost calculations of some of the negative numbers provided by net metering, but these only occur during grid export, so shouldn't affect calculations for the cost of parasitics or grid charging. Accounting for the monthly credits will depend on the metering option, but since only one credit category has a value it should be possible to just add them all up and not worry about what option was selected. I can add a function that does this in utility_rate_5 if that seems like a better way to do it. |
calculations not working for BTM
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cpaulgilman
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This approach makes sense. You can see how credits accumulate for energy charges and when the demand charge happens. I'll revise descriptions in Help accordingly.
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@brtietz I'm finally getting around to documenting these changes for Help. The default PVWatts/Commercial case has TOU demand rates with 2 TOU periods each and 2 tiers, so I was expecting to see 4 values per month in the hourly "Demand charge with system" output. But instead, I'm seeing a handful of "Demand charge with system" in $ values per month that do not always correspond to the "Electricity peak from grid" in kW, and I'm seeing negative values in the first day of the month even without billing demand ratchets. Can you help explain what these values represent?
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The intention with these is to record the incremental demand charge, so each time the demand charge increases it would produce a line proportional to the increase in the "demand charge with system" output. This is to assist with the contribution of grid charging to the LCOE and LCOS for the battery. The negative lines are definitely a bug. I'm also not sure why there would be a blue line without an orange line, so it looks like there might be two bugs here. |
Revise description of load data time convention. Remove O&M cost content from Installation Costs topics. Add ETES topics and fix broken help links. Fix typo on battery storage FOM "BTM" insteasd of "FOM" Wind resource files can now be .csv in addition to .srw Revise capacity factor descriptions for PV and Battery storage configs, #905 Wave resource instructions for converting from time series to JPD, #892 Revise PV land area calculations to account for GCR and tilt angle, #928 Add pvlib column headings to SAM CSV format description, NREL/ssc#754 Revised Operating Cost input pages Check for "annual energy" vs new "electricity to grid". Change "battery autonomy" to "autonomy". Revise power tower heliostat field to better explain how check box vs button works. Add note for degradation by year that Year 1 value should be zero, #755 Remove debt from payback period description. Also remove detailed cash flow descriptions and replace with mention of send-to-Excel with equations and spreadsheets on website. See Amir Nashed email 1/19/21 and https://sam.nrel.gov/forum/forum-general/1052 Revise Electricity Purchases page to be specific for FOM projects New LCOS metrics: #529 Electricity rates revisions from Brian. Reporting of electricity bill in time series results, see NREL/ssc#652 New parametrics features Parametrics description of how to work with SchedNumeric variables like PPA price. See Brian email 7/21/2021 Update Heliostat Field per #717 New PV slope inputs on System Design page. See #742, NREL/ssc#648 New "Limit debt fraction" Input on Financial Parameters page for PPA models New ETES model. Fix outdated description of NSRDB in Location and Resource topic UDPC updates from Ty, see Revisions 2021 folder. Also post new PDF version of Ty and Matt's description under "CSP Power Cycle Models" on SAM website https://sam.nrel.gov/concentrating-solar-power/csp-publications.html, https://sam.nrel.gov/images/web_page_files/Neises-DRAFT-user-defined-power-cycle-v3-2018.pdf Fix excess generation descriptions in help: https://sam.nrel.gov/forum/forum-general/3485. Also maybe change "Excess generation" to "Excess generation for net metering" or similar. Note for URDB download that demand ratchet data in URDB is unreliable, so check with data sheet. Demand charges with ratcheting lookback months. See Revision Notes mirletz-RE Adding billing demand lookback to SAM.msg, see [[F:\OneDrive\SAM\Utility Rates\Demand Ratchets\Initial Tests May 2021]] Update pv smoothing per Steve's email 12/9/2021 "pv smoothing question" Improve description of FOM automated dispatch. See https://sam.nrel.gov/forum/forum-general/3681 Revise electricity rates page Consolidate weekday/weekend schedule descriptions. SWH remove old hot water draw import instructions. Revise electricity purchases PPA price option not available with Specify IRR target, and purchases treated as tax-deductible operating expense. Move electricity purchases page to from Battery section to Electricity Rates and Load section Edit Lifetime Data add note about pasting data from Excel: Thousands comma separator causes paste not to work correctly, e.g, 1,000 is pasted as 1.
Doing an inter-branch pull request to test the repurposing of a few outputs. Changes:
Let me know if you want to account for monthly credits on this branch, or lcoe_lppa_energy_sales