01 Please supply any comments related to the Introduction, Definitions, or Background sections.
APS has a preference to have Tariff defined terms in the definitions in the BPM (or its own BPM) for ease of users to reference while interpreting the BPM without having to reference the Tariff and the definitions contained within it, but understand that version control, or length of BPM may be a consideration that outweighs this preference.
02 Please supply any comments related to the Resource Registration – Resource Eligibility and Timelines section.
APS has a question regarding the treatment of resources owned and operated by entities that are not participants and specifically if they are eligible for the late registration of resources in the following section, since this section notes, “Resources owned and operated by entities that are not Participants and contracted to Participants with unit or resource specific contracts (i.e., not system sales or block contracts) must be registered with the PO and provide necessary data in order for Participants to claim QCC from these resources toward their Forward Showing Capacity Requirements.
03 Please supply any comments related to the Resource Registration – Late Registration of Resources section.
See comment on question #2.
04 Please supply any comments related to the Resource Registration – Qualifying Resource Aggregation section.
No comment on this section.
05 Please supply any comments related to the Resource Registration – Generator Testing section.
Since the capability test is utilized for the base UCAP calculations it would be good to highlight that this test is needed ahead of the Advance Assessment if a participant would like it to be used in calculation of QCC. That a test done after the Advance Assessment deadline would not amend the base UCAP calculation for the resource.
APS generation engineers wanted to clarify if the ASHRAE Rated Ambient Temperature is the same as Design Temperature? Also, in the out of season capability testing section the document references a “Operational Test procedures” is that something that will be contained in another BPM or should it be added to this BPM as an Appendix or section?
06 Please supply any comments related to the Resource Registration – Operational Testing section.
Is the Net Generating Capability the value that is set every 5 years by performing the Capability Test? If so could this section be re-worded to state, “The Operational Test must be conducted at a minimum of 90% of the summer Net Generating Capability Capability Test.”?
APS has a resource that is thermal energy storage paired with solar, and believes that it would be included in the testing requirements for ESRs. Would this type of resource be considered in the ESRs section for testing purposes?
07 Please supply any comments related to the Resource Registration – New or Upgraded Unit Testing section.
How would this work if the next binding season is Winter - You can't use the Winter rating for summer, so should we require it in the next summer season? Also, should this say “binding” season or just summer/winter season?
08 Please supply any comments related to the Resource Registration – New or Upgraded Unit Testing section.
See response to #7
09 Please supply any comments related to the Resource Registration – Provision of Test Reports in the FS Submittal section.
APS believes the Capability Test should reference submission at the Advance Assessment in this paragraph, the way it reads makes us believe there is a capability test submitted at the FS Submittal which is false.
10 Please supply any comments related to the Resource Registration – Testing for Late Registered Resources section.
No comments on this section
11 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Background section.
No comments on this section
12 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Qualified Resources Included in FS Submittal That Have No QCC Previously Calculated section.
No comments on this section
13 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Thermal Resources section.
It would be helpful to address the following items in the BPM,
a) Why was EFOF selected instead of the more standard EFORd for UCAP accreditation? It would be helpful to have the rationale behind this choice along with details on the choice of the denominator utilizing CCH rather than the GADS defined denominator for EFOF. Were the Forced Outage Rates (FOR) for each unit utilized in the advanced assessment for establishing the PRM? It would be helpful to make sure the differences are noted, if any exist, between the advanced assessment to establish PRM and for capacity accreditation.
b) The paragraph references both EFOF and “equivalent outage rate”. To avoid confusion, please clarify if the rate is calculated from the factor? Noting the distinction of “factor” and “rate” in the context of GADS. <Reference>
c) Please include the rationale on why 70% of the class average is being proposed to be utilized.
d) APS requests that the PO provide the CCH and associated application of the formula for each of its thermal units.
14 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Variable Energy Resources section.
a) It appears all VERs are treated as last-in ELCC. How are interactive effects handled? What assumptions are made to reconcile the ELCCs all add up to the load and planning reserve margin established by the advanced assessment? APS contends that this is an important consideration and can be impactful.
b) How are Energy Storage resources treated when performing the ELCC accreditation study work for Solar and Wind? Are they always treated with “preserve reliability” like the ELCC accreditation study for energy storage and during the advanced assessment?
c) What transmission assumptions are included at the time of performing the ELCC study? Is this data collected prior to the ELCC study work consistent with the advanced assessment to establish PRM?
d) Further detail on how future VERs are accredited would be helpful. With each study are average-last in ELCC established so all resources are accredited the same average ELCC or do existing resources get average ELCC and new planned resources get incremental ELCCs?
If these are addressed in another BPM (perhaps 102), it would be helpful to leave a note in this BPM making that reference.
15 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Energy Storage section.
Related to the comments in #6 above APS has a thermal energy storage resource, and this section calls out pumped storage and battery storage, but does not include thermal energy storage. APS believes that this should be added as a valid energy storage resource.
b) Are batteries held to the mode of preserving reliability in the advanced assessment at the time of PRM establishment as well? It would be helpful to note that the assumption is the same or different between the PRM setting and ELCC methodology.
c) How would longer than 4 hour duration storage be treated?
16 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Hybrid Facilities section.
Would the hybrid resources be restricted by a max combined capacity in the model? Or would the accreditation be done after treating them as standalone with summing the ELCC and capping to interconnection limit? It would help to clarify. APS would recommend modeling it appropriately with a combined capacity limit in the model.
17 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Demand Response section.
APS believes the wording saying “up to 5 hours” in the first paragraph is unclear. Does this mean a program that is more than 5 hours is not eligible? We believe that it is suppose to say that QCC will be based off the performance of the DR over 5 hours.
18 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Hydro Resources section.
No comments on this section
19 Please supply any comments related to the Qualifying Capacity Contribution of Resources – Other Resources section.
No comments at this time
20 Please supply any comments related to Appendix A.
No comments at this time
General Comment
APS would support evaluation of resources utilizing PCAP methodology in the future, but is supportive of the current UCAP at this time.