solarRates Model

[dpinney]

TODO

• What other lost sales and rate models are out there?
  • Searched the literature.
  • CFC has a model internally.
• What are some historical trends?
  • Credit ratings decaying steadily since the 70s (Edison).
  • Cost of solar steadily decreasing to below $1/Watt, natch (NREL).
  • Monetizing all value-of-solar effects is incredibly subjective (NREL).
  • None of these trends immediately useful to this model.
• Input variable collection.
  • Consumption Rates: service charge plus energy charge (can't incorporate tiering due to lack of detail).
  • Demand: Form 7 residential and total sales (table R).
  • Penetration estimate is user input.
  • Net Metering rates: assume up to a user input percentage of bill.
  • Power costs: Form 7 table L.
• Specify input and output interface.
  • Monthly data put in input/output spec.
  • Annual data.
  • Do we check that all peaks are less than demand? Can't because we don't have instantaneous peak demand. Nor historical solar insolation. Also, I assume there are no cases where that much solar is added to a system.
• Questions for Rick Penry
  • How do we calculate patronage capital? I see where we can find revenue. Is it just J.3.a? Yes.
  • In your model, how do you handle wholesale demand charges? (i.e. what if DG reduces coincident peak charges?) Fudge factor based on historical peak demand days from user and panel output (TMY) coincidence.
  • How do you handle net metering? Do you assume every kWh of solar generation offsets a bought kWh regardless of time of use? Yes.
  • I figure the only two things we can predict are 7.1 and 7.3. Is that also what you did? Yes.
• Spec
  • Spec completed (see @dpinney).
  • Got input from J. P. from CFC on peak demand charges, net metering, patronage capital.
  • Got feedback from @delysis. Added future bill calculation, not going to add third customer class because the comparing bill size can be done with multiple runs of the model, added cost of solar (LCoE), added service and solar interconnect charges.
  • Everything in Excel now for formula development.
  • Merged Form 7 and Graphical models. Balancing all the numbers was... not easy.
  • Added ideal rate and average monthly bills solutions.
• Implementation as an OMF model.
  • Group inputs nicely.
  • Clean up charts with solarFinancial insights.
  • Remove PVWatts advanced inputs.
  • Remove 3 simLength inputs. Also remove aggregation function.
  • Group the inputs nicely.
  • Disable login in web.py for debug mode? Nah, just set password memory in Chrome.
  • Add labels to the Form 7 Fields.
  • Add tooltips, also to other models.
  • Missing inputs.
  • Fix BAU versus solar table to look like spec.
  • Fix formatting of the annual cash and power flow model piece.
  • Get the server started on dev laptop.
  • Flow arrow labels.
  • Power/cashflow arrows correct direction.
  • Dynamic arrow labels.
  • Value sanity check.
  • Average bill.
  • Add rate change.
• Review
  • Find "RUS financial forecast form" that Lovas mentions as key to rate design.
  • Wholesale demand charge fixes?
  • Penetration rate instead of MWh demand is now in the hybrid model.
  • Need to test values.
  • Do we assume consumer rate models other than net metering?
  • Get Russell Wasson, Dave Mohre, Jim Spiers critique of rates model.
  • Get M. Valley input?
  • Do we solve for ideal service charge instead of just rate?

[dpinney]

TODO updated.

[dpinney]

Figured out the mystery of line 7.1. By revenue and patronage capital they actually mean just revenue.

[dpinney]

Renamed to solarRates since there might be a consumer-costs-focused model.

[dpinney]

Lots of progress. Spec is coming along nicely:

[dpinney]

Form 7 and graphical models both working.

[dpinney]

Merged version created.

[dpinney]

Form 7 version complete. Oh man, what a pain.

[dpinney]

Spec complete. Available here: https://www.dropbox.com/s/tnwjza1sd6o8hes/1%20solarRates%20Spec.xlsx?dl=0

If you need to view it you'll have the password.

[dpinney]

Additional requests for this model:

1. Add kWh label to the orange flows on the diagram.
2. Label the flow diagram as "Annual Cash and Power Flow Model"
3. Add label to bill "average monthly bill per meter".
4. Change "BAU" to "Business as Usual".

Spec now reflects these things except for 1, since it's a pain to do in Excel.

[cshjin]

Add label to bill "average monthly bill per meter".

Where to add? Which data it refers?

[dpinney]

Sorry. The bill values are the ones below the consumer gray boxes and are approximatly $100.

[cshjin]

Ideally, I want to implement the interface like demo, but I got troubles with that, and pushed the ugly version 664e32f27792c41de407a890ccca02e6dcfb3400

[dpinney]

Feedback from resource planner we should implement:

• Add Kuaii billing strategy? Kuai’I, for example, has net-net billing = retail plus wholesale rates for consumers.
• Add distribution-owned solar flow of money and energy?
• Add the number of customers to each of the customer boxes?

Feedback we should not implement (yet):

• Add capacity charge calculation? Allocate to capacity charge to customer classes.
• Probably don’t do wholesale energy charges tiered at the G&T level. This issue happens when one distribution co-op uses less energy in a year than was expected, so G&T raises their wholesale price. Modeling this behavior is hard and we don’t have a good source of data or plan on how to build the feature.
• Probably don’t do time of use pricing? Kuaii has time of use pricing to shift load ON to peak (solar peak). Rate schedules typically detail the time-of-use pricing. Time of use pricing is not widely used, and implementing this is probably very hard, so we are not going to work on this.

I need to dump these here for now and get it into actionable todo items later.

[cshjin]

The new cash and power flow chart looks like this, all will be fixed as in the excel chart:

I add tooltips on each node and directed lines to display more information,

[dpinney]

Beautiful!!

[dpinney]

Fixed a bunch of stuff in the implementation. Basically ready for 1.0.

Starts with commit f145d1bb1a92fec2c3b04e74d0bc88c8104b17e6 and goes through 6712fccc5cd278bae6dd88467a5079daca3b4670

[mannanj]

Various values and dollar amounts corrected to be consistent with the "4. GOSED solarRates Spec" spreadsheet. Numbers have commas inserted and decimals fixed. Current Rates changed to "BAU Costs" and Ideal rate changed to "Solar Costs", # of decimals changed to 3. Average monthly bill for Solar and Non-Solar residential customers fixed.

Hourly Average Power graph tooltip removed. Climate graph Cell temperature and Wind speed poofed, all tooltips removed, Direct Irradiance made the default data to show, and finally the graph moved to bottom of page. Variable dump removed.