#1395 SFam PV Exception #5 - Reduced PV w/ Battery

[Scott Criswell]

Dangling item remaining from ticket #1352 - 7/7/23 comment, item #3 -
PV requirement exception 5 to Section 150.1(c)14 reads: "PV system sizes determined using Equation 150.1-C may be reduced by 25 percent if installed in conjunction with a BESS. The BESS shall meet the qualification requirements specified in Joint Appendix JA12 and have a minimum cycling capacity of 7.5 kWh as defined in Joint Appendix JA12."
Our ruleset calc of prescribed PV should apply this reduction of 25% when the user has specified a battery system >= 7.5 kWh (that qualifies under JA12).
Perhaps we also add a checkbox to the Battery inputs indicating the system meets "qualification requirements specified in Joint Appendix JA12"...?

[Scott Criswell]

ruleset & UI mods checked into SVN @ r2558 w/ most/all of this work completed.

• new checkbox added to Battery dialog tab "Battery is JA12 Compliant (to trigger standard PV reduction)" accessible for any batt w/ >= 7.5 compliance cycling capacity, when checked triggering a 25% reduction in Prescribed PV (tic #1395)

Not yet marking ticket 'Fixed' in case...

• additional reporting messaging in UI and/or report MAY be desired to document when a model's PV was reduced based on a JA12-compliant battery being included in the design

[Scott Criswell]

CEC guidance needed re: whether or not they want UI and/or report changes to document when a model's PV was reduced based on a JA12-compliant battery being included in the design.
UI to confirm when a JA12-compliant battery is present and changes to the prescriptive PV size are already implemented and tested.

[Danny Tam]

A checkbox for Exception 5 is not needed because Exception 5 is for prescriptive only. It has always been the case that you can modify the PV size with a battery.

However, it might be useful for some text to notify the user that only JA12 battery can be used for compliance, similar to how we deal with community solar. Please see the attached as my suggestion.

[Lucas Morton]

There is, nor has ever been, any indication in the ACM that Exception 5 is for prescriptive-only. If this is the Commission's intent, then perhaps the ACM should be modified accordingly.
The draft ACM (version posted on docket from last October) says the following on page 7:
*When the solar electric generation system meets one of the prescriptive exceptions in Section 150.1(c)14, the standard design is modeled with a PV system dictated by the exception limit.
*

[Scott Criswell]

Clarification needed -

The screen print provided above seem to just involve changing the label on the checkbox and add an additional URL link - but also states "A checkbox for Exception 5 is not needed".
Should we indeed show this as a checkbox, and have it display only when the capacity is above 7.5 kWh (which is written into the JA12 requirements - I believe)?

Also - by adding a battery and checking this box we actually REDUCE the standard design PV size by 25% in the CBECC-Res analysis. Am I correct in my understanding that this is intended?

[Scott Criswell]

Direction from CEC for upcoming RC release - remove logic that reduces Std design PV for JA12-compliant batteries and revise label and handling of JA12 battery compliance checkbox to REQUIRE user to check it before analysis can be performed. If user has described a battery (by entering cap > 0) and not checked the JA12 compliant checkbox, then analysis will abort w/ an error message instructing the user to either check this box or remove the battery.

Further CEC attention needed - Luke's comment above (5/20/25) calls for possible ACM changes to clarify that having a JA12 compliant battery will not result in a 25% reduction in standard design PV capacity (in performance analysis).

[Scott Criswell]

final ruleset/analysis/UI mods checked into SVN @ r2585, including:

• 25% reduction in std design PV cap removed w/ battery JA12 confirmation (this only applies to prescriptive, not performance analysis)
• the JA12 confirmation checkbox remains (in UI) and analysis is allowed for compliance cycling battery caps down to 5 kWh (as before), but the JA12 confirmation checkbox MUST be selected (Proj:BattJA12Compliant) for analysis to be performed
• extra label and button added to UI enabling access to online CEC solar equipment listings

Note to CEC per Luke's comment above (5/20/25) - please consider revising ACM to clarify that having a JA12 compliant battery will not result in a 25% reduction in standard design PV capacity (in performance analysis).

[Trevor Thomas]

@hbucaneg - please see Scott's comment(s) above regarding ACM revision.

[Lucas Morton]

As perhaps a separate discussion-- I don't think this exception will be often taken. Projects that install a battery and for some reason want to reduce PV will find that they may be handicapping their Self-utilization credit. That is-- I wonder if its worth the time to work up an ACM change, even if the intent was to have this reduction only apply to the Prescriptive compliance.