DERTF: Multi-Node Aggregation Proposal (MSC-2019-2) (20240212)

Advanced Energy Management Alliance

MISO Distributed Energy Resource Task Force (DERTF)

“Multi-Node Aggregation Proposal (MSC-2019-2) (20240212)”

February 26, 2024

Advanced Energy Management Alliance (“AEMA”) ^[1] respectfully submits the following comments to the MISO Distributed Energy Resource Task Force (“DERTF”) on the feedback request made by MISO at the February 12, 2024, meeting of the DERTF.^[2] AEMA is a trade association under Section 501(c)(6) of the Federal tax code whose members include national distributed energy resource companies and advanced energy management service and technology providers, including demand response (“DR”) providers, as well as some of the nation’s largest demand response and distributed energy resources. AEMA members support the beneficial incorporation of distributed energy resources (“DER” or “DERs”), including advanced energy management solutions, into wholesale markets as a means to achieving electricity cost savings for consumers, contributing to system reliability, and ensuring balanced price formation. These comments represent the collective consensus of AEMA as an organization, although they do not necessarily represent the individual positions of the full diversity of AEMA member companies.

At the February 12^th meeting of the DERTF, MISO introduced the subject of multi-node aggregation in the context of FERC Order 2222 and provided a straw proposal for a new market participation model for DER Aggregations that allows multi-node aggregations.

As expressed in previous comments and presentations to the MISO DERTF, AEMA strongly supports the utilization of multi-node aggregation modeling for DER.[3]^,[4] However, AEMA is concerned about the limited options of MISO’s straw proposal for market participation and offers the following comments:

• Multi-Node Aggregation Options are Important for Robust DER Participation: Allowing market participation options for multi-node aggregations establishes the opportunity for efficient collection of dispersed resources into a single response, particularly in lower density areas of the MISO footprint. Aggregation across nodes is often critical for meeting minimum participation thresholds and can establish important modeling and participation efficiencies for DER Aggregators (DERA). AEMA appreciates the willingness of MISO to explore multi-node participation models as part of DER integration to the MISO market.
• A Maximum Size for Multi-Node Aggregations is Reasonable: As suggested by AEMA in the past, MISO should initially consider a 5 MW limit for multi-node aggregations. Aggregations above this would need to be at a single node. AEMA recognizes the operational challenges of managing largely dispersed multi-node aggregations and believes that an initial limit is reasonable. Similarly, the proposed restriction to a single Local Balancing Authority (LBA) and single Load Serving Entity (LSE) are reasonable for an initial model to help manage geographically dispersed resources. As MISO and stakeholders gain experiences with these resources, MISO should consider relaxing this size limit and reexamining the restrictions on cross LBA/LSE modeling.
  
  
• Distribution Factor Calculations Should Reflect System Impacts of Resources: Ideally, the determination of the prices associated with aggregated resources should reflect the economic drivers for dispatching the resource. For example, as price signals across the aggregation exceed the clearing price of the resource, then the aggregated price should translate to the aggregated settlement price to keep the resource whole to dispatching price signal. Unfortunately, integrating dynamic, real-time distribution factors can be complex, so MISO might consider simply weighting the aggregated price by the registered capacity of the individual DERs at each pricing node.
  
  
• A System Wide Limit may be Reasonable for Initial Modeling: MISO has asked if a system wide limit should be introduced. AEMA understands that as MISO begins the process for modeling multi-node aggregations, there could be concerns about the impact on operational systems for significant levels of integration. AEMA would suggest an initial limit of 500 MW across the system until operational experience is gained and the market impacts are better understood. A 500 MW limit would restrict participation to 100 resources 5-MW resources and is relatively small compared to the entire MISO footprint. The concern about a potential limit is an illustration of why MISO should move forward with an early participation opportunity ahead of the long-term implementation plan of 2029. Even limited participation of DER can provide important insights into how these new participation models will impact market operations.
  
  
• MISO’s Straw Proposal is Flawed: In its straw proposal, MISO has suggested that a multi-node aggregation would be an energy only, settlement only price taker in the markets. AEMA strongly disagrees with this aspect of the proposal. This specific aspect of the proposal is problematic to AEMA members because the limitation prevents efficient integration of the resources into the MISO market model and does not capture the economic benefits of these resources. As a “price taker” resource, these resources would effectively not be participating in the MISO market because they would be reacting entirely independent of MISO operations. According to MISO Tariff restrictions, resources that are price takers are not made whole to offer prices and will not fulfill the capacity commitment obligations. Only as a fully integrated part of the MISO Day-Ahead and Real-Time commitment models can the full value of these resources be realized in the MISO system.

AEMA does not believe that an energy-only, price-taker in the market meets the intent of FERC Order 2222, which requires integration into the MISO markets. As a price-taker, the resource would be acting independent of MISO operations. An energy-only designation would not allow the resource to provide and be compensated for the ancillary services that it is capable of reliably supplying.

• DER can Efficiently Provide Ancillary Services: The current straw proposal from MISO would not allow multi-node resources to provide Ancillary Services like Spinning Reserve. AEMA strongly disagrees with this aspect of the proposal. Ancillary Services compose an important part of the MISO market participation opportunity for many DER resources. For Demand Response in particular, the opportunity to continue to operate while reliably providing spinning and supplemental reserves is important to their participation revenues. MISO is on the right track with allowing multi-node aggregations, but participation in the ancillary services market is an important aspect of any reasonable proposal. MISO should revise the straw proposal to allow energy and ancillary service market participation.

AEMA appreciates consideration of these comments by MISO staff as part of compliance to FERC Order 2222. We welcome any questions, and encourage you to contact either Katherine Hamilton, Executive Director of AEMA, or DeWayne Todd, representative of AEMA, should you wish to discuss this with AEMA members.      

Respectfully Submitted,

Katherine Hamilton
Executive Director, Advanced Energy Management Alliance
Katherine@aem-alliance.org
202-524-8832

or

DeWayne Todd
DDT LLC
dewaynetodd1297@gmail.com
812-573-8052

[1]  For additional information, see AEMA website: http://aem-alliance.org

[2]  20240212 DERTF Item 04d Multi-Node Aggregations (MSC-2019-2).pdf

[3] Slide 34 of April 12 DERTF meeting presentation, https://cdn.misoenergy.org/20210412%20DERTF%20Item%2007%20MISO%20Straw%20Participation%20Model%20AEMA539533.pdf    

[4] Slide 8 of May 10, 2021 DERTF meeting presentation, https://cdn.misoenergy.org/20210510%20DERTF%20Item%2004%20MISO%20Straw%20Participation%20Model_Voltus548198.pdf

Voltus, Inc.  Feedback regarding  the MISO DERTF Strawman Proposal for Multi-Node Aggregation presented February 12, 2024

Submitted February 23, 2024

Voltus is encouraged that MISO is exploring adding a multi-node aggregation model to the market design.

As pointed out in the February 12, 2024, presentation, FERC ordered MISO in its response to MISO’s Order 2222 compliance filing to either:

(1) provide a detailed technical explanation as required by Order No. 2222 to demonstrate that it is not technically feasible for DERs to aggregate more broadly than a single-node, as proposed; or (2) propose alternative locational requirements that are as geographically broad as technically feasible, as well as a detailed technical explanation for the geographical scope of these alternative locational requirements.^[1]

In apparently adopting option “2”—proposing alternative locational requirements (the multi-node construct)—DERTF’s straw proposal does take constructive step forward. However, as discussed below, the straw proposal leaves out any details that would facilitate meaningful feedback, including, most importantly, the mandated “detailed explanation for the geographical scope of these alternative locational requirements.”

Order 2222 emphasizes the vital role of aggregation, mandating ISOs to permit aggregations that are "as geographically broad as technically feasible." FERC specifically encouraged permitting aggregations of DERs “that are smaller, interconnected at lower voltages, and geographically dispersed” because they “can provide new cost-effective sources of energy and grid services and enhance competition in wholesale markets.”^[2]   Facilitating aggregations as geographically broad as technically feasible is crucial for enabling small assets that individually fall short of meeting minimum size requirements to access wholesale markets. By permitting multi-node aggregation, aggregators can create fewer but larger resources and reduce the management burden for ISOs and distribution utilities. This consolidation is less burdensome and complex than numerous small assets attempting direct entry into the wholesale market.

The DERTF straw proposal introduces several restrictions, with no explanation, that appear to be inconsistent with and in some instances contrary to the objectives in FERC Order 2222, and, more specifically, guidance in FERC’s Order on MISO’s 2222 compliance filing. 

Voltus would direct MISO to a Strawman Proposal that Voltus presented during the May 2021 DERTF meeting^[3] that provides a useful framework for multi-node aggregation and aligns with FERC objectives.

For example, FERC recognized “that the appropriate locational requirements may differ based on the services that a distributed energy resource aggregator seeks to provide (e.g., the locational requirements for participation in the day-ahead energy market may differ from those for participation in ancillary service markets).”^[4] Consistent with this recognition, the Voltus Strawman provided that “[a]ggregation levels should be based on the parameters of the service provided” and included the following detailed examples: 

For capacity programs designed to address large-scale emergencies and dispatched by LBAs, aggregations should form within LBAs.

Ancillary service products, which cater to zonal-level needs, should be able to aggregate within Ancillary Service Zones. For instance, PJM's 2222 proposal permits zonal aggregations for Capacity and Regulation, while reserve zone aggregation is allowed for Reserves. Energy pricing can vary by EP node, but the precedent set by MISO’s  DRR 1 resource type indicates that aggregated products can aggregate by CP Node with distribution factors for pricing across associated EP nodes. However, the use of CP Nodes can be challenging due to frequent changes caused by retail customers switching service providers, leading to potential inaccuracies in aggregation data. Long-term, a pricing structure based on real-world factors like transmission constraints rather than LBA/LSE combinations should be developed. Several entities, including MISO, California ISO, New York ISO, and PJM, permit distributed assets to aggregate across pricing nodes.

Generally, Voltus supports a construct where there is alignment across the level (zonal, nodal, etc.) for three attributes:

1.  the level at which pricing is set,
2.  where dispatch decisions are made, and
3. how aggregations can form.

Where pricing and dispatching are set at different levels, aggregations should form at the level that is “as geographically broad as technically feasible” per FERC mandate.

The DERTF have asked for feedback regarding questions from slide 6 of its Multi-Nodal Aggregation presentation, however, before those specific questions can be answered, details and clarification regarding the DERTF Strawman Proposal need to be addressed.  Regarding the specific restrictions listed in DERTF’s Strawman Proposal presented at the February 12, 2024, DERTF meeting, Voltus has the following questions and comments –

1. Add a multi-node alternative specific to DER Aggregations – Again, Voltus appreciates the constructive step forward in proposing a multi-nodal alternative. As pointed out in the Voltus Strawman, allowing the Aggregators to aggregate multi-nodally would reduce the burden on MISO and distribution utilities to study individual aggregations.
2. Price taker – It is unclear why DER Aggregations must be a price taker in order to participate in a multi-nodal aggregation, and the proposal lacks any explanation for such a restriction. Such an explanation would be helpful in determining (a) what specific issue or problem MISO is attempting to solve, and (b) whether this restriction is an appropriate resolution consistent with FERC Order 2222.  Is MISO proposing that DER Aggregations self-schedule, and if so, why? Is there a concern regarding whether certain type(s) of DER technology are dispatchable, i.e., able to respond to MISO’s 5-minute dispatch signal?^[5] If this is the case,  why is there no recognition of the capability of aggregators to aggregate resources, such as a battery storage resource along with a roof-top solar resource such that the aggregation, i.e. the entire Distributed Energy Aggregated Resource (DEAR) is dispatchable? The DERTF Strawman Proposal provides no explanation or justification for why DER Aggregations must be a price taker.  
3. Settlement only – It is also unclear why MISO is proposing a settlement only option for multi-nodal aggregations. MISO does not have any experience with a “settlement only” market resource and, again, provides no explanation or justification for the restriction. During the February 12 DERTF meeting, MISO mentioned ISO-NE^[6] has a settlement only generator option. To comply with FERC Order 2222, ISO-NE proposed a new market participation model - Settlement Only Distributed Energy Resource Aggregation (SODERA). However, to comply with FERC Order 2222, MISO proposed a “DER Grouping”, and as MISO stated in its response to FERC,^[7] “DEARs will be settled based on meter data submitted for each DER Group within a DEAR”. The SODERA model, introduced in the ISO-NE Compliance proposal would not be dispatchable by the ISO and wouldn’t provide telemetry data.^[8] More importantly, there is no explanation of  why a Settlement only DEAR is needed for multi-nodal aggregation and how it would offer any benefits contemplated by FERC Order 2222. As the Advanced Energy Management Alliance (AEMA) noted in their ISO-NE protest^[9] at FERC, the SODERA model does not work for most behind-the-meter DERs because it does not capture the value of load reductions, and leads to metering issues.

4. Limit to Local Balancing Authority Area and single Load Serving Entity – Voltus continues to be concerned about this single LBA and LSE requirement particularly given the absence of the required “detailed technical explanation for the geographical scope of these alternative locational requirements.” Once the new Market Systems Enhancement is implemented, Voltus is hopeful that MISO engages a stakeholder discussion on prioritizing this market improvement. In the meanwhile, while allowing multi-nodal aggregation within a single LBA and an LSE is a welcome improvement, Voltus would urge MISO to consult the Voltus Strawman proposal’s conclusion that “aggregation levels should be based on the parameters of the service provided” which is more consistent with FERC directives on this issue.
5. Must enroll individual DER – This requirement is similarly unclear and there is no explanation or justification provided in the DERTF Strawman Proposal. In MISO’s initial compliance proposal to comply with the FERC Order 2222 requirement regarding a market participation model, MISO proposed “DER Grouping” and FERC accepted MISO’s DER Grouping proposal. It is not clear why individual DERs must be enrolled for multi-nodal aggregation, when, as MISO stated in its data request response to FERC,^[10] enrollment of DER in a DEAR is maintained in the commercial model.

To formulate a thoughtful response to MISO’s questions for stakeholder feedback, the above questions regarding the DERTF Strawman proposal need to be answered and more detailed technical explanation, as FERC has repeatedly urged, is required.  However, recognizing that MISO’ extension to respond to FERC’s Order on its Compliance Filing extends only to May and and in the interest of advancing the stakeholder dialogue with MISO, we are providing the following responses, some of which could change once we understand MISO’s Straw Proposal better.

Should a maximum size be adopted?

Without sufficient technical analysis that shows if adopting a maximum size of an Aggregation leads to better outcomes, such as market engine solving times, Voltus is not in favor of MISO adopting a maximum size for market design. Any size limitations adopted that would hamper the FERC requirement of “as geographically broad as technically feasible” must be avoided. 

How should distribution factors be calculated?

Aggregators such as Voltus would be able to calculate distribution factors since they know the DER customers and their performance. MISO should provide a field in the market design for Aggregators to input distribution factors for each DER within an Aggregation. See an illustrative example below based on MISO’s August 30, 2021, DERTF presentation and MISO Network and Commercial Models BPM - 010.^[11]

Additionally, as the Network and Commercial Models BPM – 010 illustrates in Section 4.2.1.5. Aggregate Generation Assets: Generation Assets can be aggregated. However, the Aggregated offer should not be disaggregated on an hourly basis.^[12] Similar restrictions can be imposed on Aggregated DERs.

Should a system wide limit be introduced?

Voltus does not support a system limit that could jeopardize the “as geographically broad as technically feasible" FERC requirement for multi-nodal aggregation. Additionally, in MISO’s resource adequacy construct, as an example, there exists Capacity Import and Capacity Export Limits that limit the capacity that could be traded among Market Participants.^[13] Similarly, for Ancillary Services Reserve Zones, there exist limits on the amount of reserves procured (400 MW for regulation, 930 MW for Spinning Reserve, 1,105 MW for Non-Spinning Reserve, 1,800 MW for Ramp products and 3,600 MW market wide limit for Short-Term Reserve product).^[14] Finally, there is a limit between the North region and the South region of MISO.^[15] Hence, it is Voltus’s opinion that sufficient limits already exist in the MISO market, and there is no need for additional limits.   

Again, Voltus appreciates MISO’s efforts on this issue and encourages additional details and dialog.  We also note that the DERTF suggested more information regarding implementation will be forthcoming at the March meeting. Voltus agrees with other stakeholders that clarity on implementation timeline as soon as feasible is the preferred approach.

^[1] 185 FERC ¶ 61,011, (ER22-1640-000, ER22-1640-001), paragraph 136.

^[2] 172 FERC ¶ 61,247, Order No. 2222, paragraph 27.

^[3] https://cdn.misoenergy.org/20210510%20DERTF%20Item%2004%20MISO%20Straw%20Participation%20Model_Voltus548198.pdf (“Voltus Strawman”).

^[4] 172 FERC ¶ 61,247, Order No. 2222, paragraph 188.

^[5] See “Resources within the Market Footprint can participate in the Real-Time Energy and Operating Reserve Market by submitting Resource Offers provided they can respond to 5-minute Dispatch Setpoint Instructions. These Resources are termed “dispatchable”. A Resource that is considered dispatchable but does not consistently follow Setpoint Instructions may be reclassified as non dispatchable. Such considerations are made on a case-by-case basis considering severity, number of occurrences, and reasons for deviations from Setpoint Instructions. All other Resources (not able to respond to a 5-minute dispatch signal) except DRRs-Type I must Self-Schedule their Resource output.” Energy and Operating Reserve Markets Business Practices Manual BPM-002

^[6] https://www.iso-ne.com/participate/applications-status-changes/asset-registration

^[7] Page 28, MISO’s response to FERC, October 11, 2022. https://elibrary.ferc.gov/eLibrary/filedownload?fileid=AD54B3CF-21E4-CFFA-A567-83C89D000000.

^[8] https://www.iso-ne.com/static-assets/documents/2022/02/order_no_2222_filing.pdf.

^[9] Page 24, Protest of Advanced Energy Management Alliance in Docket No. ER22-983, https://elibrary.ferc.gov/eLibrary/filelist?accession_number=20220401-5531&optimized=false

^[10] Page 28, MISO’s response to FERC, October 11, 2022. https://elibrary.ferc.gov/eLibrary/filedownload?fileid=AD54B3CF-21E4-CFFA-A567-83C89D000000.

^[11] https://cdn.misoenergy.org/20210830%20DERTF%20Item%2003%20Review%20of%20EP%20and%20CP%20Node%20Creation583585.pdf

^[12] See, “For operational purposes, if an aggregate Asset is created, the decision on whether to Offer as independent units or as an aggregate must be done on a daily basis. MPs will not be allowed to change their Offer basis from the aggregate to individual units on an hourly basis. If an aggregate Offer is made and cleared in the Day-Ahead Energy and Operating Reserve Market, the Real-Time Offers must also be submitted on an aggregate basis for that Operating Day.” Section 4.2.1.5. Aggregate Generation Assets. Network and Commercial Models Business Practices Manual BPM-010-r18

^[13] https://cdn.misoenergy.org/LOLE%20Study%20Report%20PY%202024-2025631112.pdf

^[14] Slide 10 here - https://cdn.misoenergy.org/20211102%20STR%20Workshop%20Presentation%20(IR010)600624.pdf

^[15] https://cdn.misoenergy.org/SRIC_SREC%20Posting%20for%202023_24%20PRA628233.pdf

CPower Comments Regarding DERTF Multi-Node Aggregation (MSC-2019-2)

February 26, 2024

During the February 12, 2024 DERTF meeting, MISO presented its Multi-node Aggregation proposal to address FERC’s directive to MISO to file a further compliance filing to comply with Order No. 2222. Enerwise Global Technologies, LLC d/b/a CPower (“CPower”) appreciates the opportunity to provide feedback to MISO on these issues. CPower thanks MISO staff for their review and consideration of the feedback below. Should you have any questions, please do not hesitate to contact Peter Dotson-Westphalen.

MISO’s proposal for enabling multi-node aggregations is to add a multi-node alternative to the single-node model as MISO proposed in its initial compliance filing to FERC. In the proposed multi-node model, a DER Aggregator would be able to register DERs within a single LBA and served by a single LSE and each individual DER must be included in the enrollment. However, the DER Aggregation would be a settlement-only resource, and act as a price taker. During the presentation, the presenter clarified in response to stakeholders’ questions that these multi-node aggregations would not be submitting bids directly into the market but could avail themselves of submitting virtual bids into the Day-Ahead (“DA”) market.  

MISO’s proposed multi-node alternative effectively limits these aggregations to act on their own – outside of MISO’s market and dispatch with little to no visibility leading up to real-time (unless utilizing virtual DA bids) – to provide only energy, and not be able to participate to provide capacity or any ancillary services the DERs comprising such an aggregation may otherwise be capable.

CPower strongly supports multi-node aggregations at the largest geographical range that is technically feasible. CPower appreciates MISO’s time and effort spent developing a proposal to enable multi-node aggregations. However, creating an energy-only alternative may not be attractive to DERs that may be too small to meet the 100kW minimum threshold to participate under the single-node model.

MISO has not yet provided further detail as to why DER Aggregations formed across multiple EPNodes to larger geographic areas than a single node is not technically feasible to allow such DER Aggregations to provide all the services it is capable. For example, end use customer facilities participating as Demand Response Resources (DRR) Type I may aggregate across multiple EPNodes to provide energy and ancillary services, while also being registered to provide capacity (either as a Capacity Resource or a Load Modifying Resource). It is unclear why MISO cannot accommodate a similar approach for DER Aggregations with DERs located at different EPNodes within the same LBA and with the same LSE.

Additionally, MISO asked the following questions regarding the Multi-Node Aggregation proposal.

Should a maximum size be adopted?

No, there should not be a maximum size adopted for multi-node aggregations, unless MISO conducts and presents a technical analysis on why such a maximum size is necessary to maintain system operations and reliability.

How should distribution factors be calculated?

It remains unclear to CPower what the purpose of submitting distribution factors may be if the multi-node alternative remains as proposed and moves forward, seeing as these aggregations will not be contributing to price formation in the market as a settlement-only resource. Should MISO move forward with this proposal as it was presented, CPower requests MISO further clarify whether there is a need for distribution factors is and, once clarification is provided, solicit additional stakeholder feedback on how it should approach calculating such values.

Should a system wide limit be introduced?

No, there should not be a system wide limit to multi-node aggregation resources, unless MISO conducts and presents a technical analysis as to why a system wide limit on such aggregations is necessary to maintain system operations and reliability.

Conclusion

CPower appreciates the opportunity to comment and looks forward to further discussion of this topic in the stakeholder process.

Respectfully,

Peter Dotson-Westphalen

Sr. Director, Regulatory & Government Affairs

CPower

Peter.D.Westphalen@CPowerEnergy.com

781-214-7523

American Municipal Power (AMP) appreciates the opportunity to provide feedback on MISO’s Multi-Node Aggregation Proposal and offers the following comments regarding the straw proposal presented on slide 5 of MISO’s presentation:

• AMP recommends limiting the aggregates to a single distribution utility. It is possible for a single LSE to serve multiple distribution utilities. An aggregate across multiple distribution utilities could lead to confusion at the distribution utility level when communicating the individual resources that will be dispatched within a particular distribution utility.
• AMP does not support the “price taker” element of the straw proposal. If these are market resources, they should be able to set price.

Additionally, regarding the design decisions shown on slide 6 of MISO’s presentation, AMP offers the following comment:

• AMP does not believe a maximum size should be adopted. MISO has not provided sufficient evidence that there is an issue that could or needs to be resolved by imposing a maximum size.

The OMS Distributed Energy Resources Work Group (DERWG) provides this feedback to MISO on its Multi-Node Aggregation Proposal (MSC-2019-2). This feedback is from an OMS work group and does not represent a position of the OMS Board of Directors. 

The DERWG supports MISO’s exploration of multi-nodal aggregation for DERs per FERC’s compliance directive. Depending on the rules and processes implemented, multi-nodal aggregations may allow DERs to participate more fully in MISO’s markets. In particular, multi-nodal aggregation may provide opportunities for smaller DERs to aggregate in order to meet MISO’s minimum size requirement to participate in wholesale electricity markets, and this opportunity should be further studied. The DERWG encourages MISO to reframe its position in its forthcoming multi-nodal aggregation proposal as a first step. Over time, MISO’s visibility into DER performance will improve. As new technology emerges and MISO’s experience with DERs grows, MISO should consider regular updates to its multi-nodal aggregation policies. 

WEC Energy Group shares the concerns raised by MISO and other stakeholders that multi-node aggregation of DERs could lead to market distortion and reliability risks.  As we have seen with the deployment of LMRs (Demand Response - DR), calling on DR over a wide footprint may not alleviate congestion and in fact may contribute to congestion.  Because of this, MISO and stakeholders are working on changes to the registration of DRs to provide more granular location information, better market signals, and more granular deployment.  The same issue occurs with multi-node aggregation of DERs - deployment of DERs over a wide geographical area may not provide the intended result.  MISO and the local balancing areas require granular information on DERs to maintain reliability and proper market signals.  This may require more advanced telemetry, metering, real-time data reporting, and settlements for DERs, especially if a single DER is comprised of multiple resources on many different nodes.  While we understand the flexibility sought by aggregators of DER, reliability and market signals should not suffer as a result of multi-node DERs.

WPPI offers the following feedback on MISO’s Multi-node Aggregation straw proposal (DERTF, 2/12/2024, item 04d) design questions:

(1.) Should a maximum size be adopted?

• (a.) Given MISO won’t be dispatching, if the dispatch at any of an aggregation’s EPNodes may result in flows on the transmission system (potentially exacerbating congestion), then it would seem a limit on the aggregation’s MW at such an EPNode would be helpful. In such a situation, is there a maximum size MISO would suggest?
• (b.) On the other hand, it doesn’t seem a maximum size would directly address issues with the accuracy of distribution factors – i.e., weights used to combine pricing information from multiple Elemental Pricing Nodes (EPNodes) to calculate a single Commercial Pricing Node (CPNode) price for settlement of the multi-node aggregation.

(2.) How should distribution factors be calculated?

• The accuracy of distribution factors, which will determine the accuracy of the prices used to settle aggregations, is WPPI’s primary concern with multi-node aggregations.
  • In the case of Load Zone (which consists of an aggregation of EPNodes): MISO Tariff Module C 2.9.f.ii (day-ahead, real-time analogous) “The weighting factor for a specific Elemental Pricing Node is equal to the ratio of the Load Zone’s demand at the Elemental Pricing Node to the total demand of the Load Zone as determined by the results of the State Estimator from the average over the twenty-four (24) hours of seven (7) Days prior to the Operating Day.”
  • Even in the case of a Load Zone the EPNode weights are an estimate; however, load tends to behave consistently. It doesn’t seem a multi-node aggregation will have the same level of consistency.
• To address the accuracy of distribution factors, WPPI has only one idea at this time: Limit multi-node aggregations to EPNodes in the same “group,” where a group consists of EPNodes that MISO has determined, on a planning year (Jun-May) basis, can reasonably be expected to have similar prices. Such an approach would mitigate the importance of accurate distribution factors.
• QUESTION FOR MISO: Has MISO considered the implications of the accuracy of State Estimator data for pricing Load Zones given the impact of aggregations (single or multiple EPNodes) on those data?

(3.) Should a system wide limit for multi-node aggregations be introduced?

• Even if the size of individual multi-node aggregations are managed as needed (e.g., as discussed under (1.)), perhaps a system wide limit for multi node aggregations is needed to address MISO’s lack of visibility into the load that will be taken off the system by such multi-node aggregations (as Load Serving Entity purchases will not be reduced for distributed energy resources participating in MISO). To address such visibility concerns, is there a system wide limit on multi-node aggregations MISO would suggest?

(4.) Do you have additional design questions MISO should consider?

• (a.) MISO is proposing to limit a multi-node aggregation to EPNodes within a single Local Balancing Authority and single Load Serving Entity. However, this may not be sufficiently narrow given a single LBA/ Load Serving Entity may include multiple Electric Distribution Companies. Consider limiting an aggregation to EPNodes within a single EDC given EDC must review (60 days) aggregation and to facilitate cross-check by a single Relevant Electric Retail Regulatory Authority (e.g., city council for a municipal utility, governing board of a cooperative utility, state public utility commission).
• (b.) WPPI understands the concern with limiting an aggregation to a single EPNode is that it will be difficult to reach the 100 kW aggregation threshold. If that is the case, instead of introducing a multi-node aggregation and the complications it brings, consider reducing the aggregation threshold to [50] kW.

ITC RESPONSE TO DERTF Questions – Due to MISO 2-26-24

ITC appreciates the opportunity to respond to the questions raised by MISO on Multi-node Aggregations.

ITC Encourages MISO to Retain Single Node Aggregations, Order 2222 Does not Require Multi-Node Aggregations

ITC encourages MISO to retain the existing construct of single node aggregations. Order 2222 does not require RTOs to offer multi-node aggregation capability.[1]  FERC raised the issue of technical capability of multi-node aggregations. Technical capability does not mean that the outcome is the most efficient and reliable outcome. We encourage MISO to consider responding to FERC’s directive by elucidating these points—perhaps touching on some of the ideas and concerns set forth below. The fact that multi-node aggregation may be technically feasible, does not inherently mean multi-node aggregations provide the most efficient and reliable outcome.

Multi-node Aggregations Create a Zonal Market within a Locational Marginal Price Market Leading to Preventable Inefficiency

Multi-node aggregations introduce inefficiencies to modeling and system operations that could impact both economics and reliability.  Such inefficiencies have been acknowledged by MISO.[2]  Aggregations across multiple nodes will create a zonal markets within MISO’s Locational Marginal Price (LMP) based market—contributing to the “hyper-complex risk environment” [3] MISO describes in its most recent Reliability Imperative Report. Studies exist on inefficiencies of zonal electricity markets [4]—not to mention the real-life decision of the ERCOT market to transition from a less efficient zonal construct to a more efficient and precise nodal construct.

With the drive to efficiency and reliability, why choose to implement a known source of inefficiency by allowing what are considered “individual” resources to aggregate and dispatch over multiple nodes? Locational Marginal Price markets are location-specific—hence the name. Dispatch of a single aggregated resource across multiple nodes is not location specific. In addition to introducing economic inefficiencies, multi-node aggregations could introduce operational issues because of the lack of transparency at the MISO level in both measuring and modeling and in Real-Time deployment response.

Multi-node aggregations undermine the intent of locational pricing which is the entire basis of nodal markets used to provide reliable system operation. Marginal energy dispatch subject to resource/system constraints identifies where energy is the most valuable, and, develops LMPs/dispatch signals to manage the reliability of the system. This fact is paramount. Energy and Ancillary Service markets are in place to create reliable operations—they are the main tools used to ensure system reliability. Undermining the reliability incentive created by LMP markets by intentionally creating zonal market responses within the LMP construct through multi-node aggregation strikes at the very premise of LMP markets.  Thus, multi-node aggregations should be avoided. (Not mentioned here are potential inter-actions between energy and ancillary service deployments across multi-node aggregations by both the same and by other Aggregators…yet another foreseeable concern.)

Lack of Transparency Across Multi-node response will contribute to Inefficient Market Outcomes and Affect Operations and Decision Making

The fact that distribution factors would have to be provided for multi-node aggregations at registration does not automatically mean that the resource would be deployed in alignment with the distribution factors. The deployment response—the choice of which components of an aggregation to dispatch, and for multi-node aggregations, across which node(s) to respond, is up to the Aggregator. Thus, despite providing distribution factors, the actual response of the aggregations dispatched in response to a MISO dispatch instruction may not mimic the distribution factors provided at registration. This could contribute to a lack of situational awareness for MISO and TOs. While Aggregator latitude (about which components to deploy) exists with single node aggregations, the situation is exacerbated with multi-node aggregations because the aggregator would not be required to tell MISO ahead of time which node(s) will be impacted by the Aggregator’s choice of which components to deploy in response to a dispatch instruction.

The deviation in response between the distribution factors and the actual response will introduce two types of inefficiency in the MISO dispatch solution—volumetric and locational—and as noted elsewhere, will contribute to reduced situational awareness for all stakeholders.  For example, an Aggregator could choose to respond fully with resource components from a single node within a multi-node aggregation—for several intervals and at another node for other intervals.  Hourly integration as provided for under MISO Attachment TT does not appear to discourage this type of response. Thus, MISO could be expecting response to a deployment instruction across multiple nodes, and, get limited or no response from a particular node (or more than expected at another node) when it (MISO) modeled deployment at that node to establish both the dispatch instruction and the LMP for that interval.  The lack of a size limit on Aggregations makes the issues of observability, deployment transparency, and response measurement even more concerning, particularly as it relates to congestion management and price formation.  LMPs are the signals to which other Market Participants respond, and upon which they rely for both Real-Time and longer-term decision making--to value energy, plan for new generation, and make hedging decisions to protect their customers and assets. TOs rely on LMPs so that resources are incented to follow MISO instructions to manage congestion.

Multi-node Aggregations Create Another Layer of Complexity in State Estimation and System Operation

MISO State Estimation will be negatively impacted by the lack of observability in multi-node response at the MISO level.  The lack of precision in resource output potentially introduced through single node aggregations is exacerbated by multi-node aggregations. This additional element of imprecision will layer on top of the other elements that MISO and all RTOs are struggling to refine, most notably, renewable output forecasting models. State Estimation relies on the most precise real-time inputs and forecasts available to produce the basis for the most efficient and reliable security constrained dispatch for the next interval(s). To the extent the response of a resource cannot be reasonably estimated, deployment signals for other Resources will not be where they should be, or as precise as they could be, to achieve the most efficient pricing and, most importantly, the most efficient reliability outcome.  This could impact not only other resources, but also the amount and deployment levels of Ancillary Services—thus creating market wide ripples of impact.

If the Choice is Made to Support Multi-Node Aggregations

If MISO and other stakeholders support moving forward with multi-node aggregations:  such aggregations should be limited to the geography of a single LBA, and a system wide limits on multi-node aggregations and multi-node aggregation sizes should both be implemented.  Interval metering and additional telemetry should be discussed as requirements for multi-node aggregations and their components to help address and mitigate the observability and pricing issues raised above. MISO should require aggregators to provide telemetry by node for elements of a multi-node aggregation to support situational awareness and dispatch verification. Interval metering would be helpful to validate distribution factors and for output verification by node so that a response-weighted LMP could be calculated by interval for settlement. 

In closing, multi-node aggregations have the potential to introduce additional operational complexity and inefficiencies over those posed by single node aggregations. Retaining the existing single node construct helps to mitigate foreseeable negative externalities for operations, pricing, congestion management that multi-node aggregations could introduce.

Marguerite Wagner

Director Regulatory - Energy Markets & Innovation

email  mwagner01@itctransco.com
www.itc-holdings.com | www.modernizethegrid.com

27175 Energy Way | Novi, MI 48377

[1] “…we are not requiring RTOs/ISOs to establish multi-node distributed energy resource aggregations.” RM18-9-000; Order No. 2222 at 174.

[2] See MISO Slide 10:  20210510 DERTF Item 03b Requirements for Aggregations548067.pdf (misoenergy.org)

[3] See February 2024 MISO Reliability Imperative report 2024 Reliability Imperative Report Feb.21 Final (misoenergy.org)

[4] https://web.stanford.edu/group/fwolak/cgi-bin/sites/default/files/triolo_and_wolak_ercot.pdf

DTE Electric appreciates the opportunity to provide feedback on the Multi-node Aggregation.

DTE agrees If multi-node aggregation is allowed, it needs to be constrained under single LSE or single LBA. Moreover, if power flow congestions are found to exist within one LSE or one local balancing authority, either at transmission or distribution level, there needs to be a process in place to further constrain the multi-node aggregation to the area with no apparent power flow congestion to enhance the consistency and stability on distribution factor calculation and the fairness and prudency on DER billing and settlements.

DTE believe that MISO should map individual DERs in their planning and operations network models, given the additional complexity in settlements and operational challenges that come with multi-nodal DER aggregation. This will allow sufficient granularity to ensure wholesale needs do not violate safety and reliability of the hosting distribution systems.

MISO needs to clarify how CROW operational constraints will be managed for multi-node injecting resources.

Lastly, we strongly recommend MISO to invite other ISO/RTOs to share with MISO task force stakeholders on their approach of multi-nodal aggregation. PJM may be of particular reference value given the similarity of the market construct between PJM and MISO.

Advanced Energy United appreciates the opportunity to submit these comments in response to the Midcontinent Independent System Operator, Inc.’s (MISO) request for stakeholder feedback on its Multi-Node Aggregation Proposal (MSC-2019-2) straw proposal design, following its February 12, 2024 Distributed Energy Resources Task Force Meeting.

Advanced Energy United is a national association of businesses that are making the energy we use secure, clean and affordable. Advanced Energy United is the only industry association in the United States that represents the full range of advanced energy technologies and services, both grid-scale and distributed. Advanced energy includes energy efficiency, demand response, energy storage, wind, solar, hydro, nuclear, electric vehicles, and more. The comments expressed in this submission represent the position of Advanced Energy United but may not represent the views of any particular member.

Advanced Energy United supports MISO’s efforts to create opportunities for multi-node aggregation for distributed energy resources (DER), rather than limit aggregations to a single node model. Limiting the formation of a DER aggregation to only DERs located at a single pricing node will create significant barriers to participation because aggregators may be unable to form a DER aggregation at a single pricing node that is large enough to meet the minimum size threshold of 100 kW. Even for those aggregations able to meet the 100kW threshold, being limited to a single node for aggregation reduces flexibility and constrains participation.

However, MISO’s proposed solution, while still in the early stages of the stakeholder process, lacks technical justification and will likely have limited utility as initially introduced. MISO proposes four criteria but has provided no analysis demonstrating that the proposed requirements are as “broad as technically feasible,” as instructed by FERC. As a threshold matter, MISO has not demonstrated that it is not technically feasible to allow multi-nodal aggregation without restrictions. MISO also has not provided a detailed technical explanation of its proposed restrictions, such as the need for the aggregation to be a price taker, settlement-only, limited to local balancing authority area and single load serving entity, and to enroll individual DER.

Advanced Energy United offers the following concerns regarding MISO’s four proposed criteria, which we believe will limit the utility of the multi-nodal option:

1. Price taker/settlement only: This criteria will limit the value of the multi-nodal aggregation option to aggregators, and limit its usefulness to MISO and the market if these resources are not able to respond to real-time market signals and need. Additionally, MISO’s settlement-only energy market participation proposal would prevent DER from participating in MISO’s capacity and ancillary services markets and providing valuable grid services, which does not meet the goal of Order No. 2222 to “allow distributed energy resources to provide all services that they are technically capable of providing through aggregation.”[i] Other markets have allowed multi-nodal DER participation in capacity and ancillary services markets, even if they had originally proposed only a single-node model for the energy market, such as PJM.[ii]
2. Limit to Local Balancing Authority Area and single Load Serving Entity: Advanced Energy United requests that MISO demonstrate that this criteria alone does not adequately constrain multi-nodal aggregation without the need for additional restrictions.
3. Must enroll individual DER: Before proposing additional enrollment requirements that may be burdensome to both aggregators and to MISO, Advanced Energy United requests that MISO explain why such requirements are necessary to accommodate multi-nodal aggregation.

Regarding the straw proposal design questions, Advanced Energy United offers the following responses:

1. Should a maximum size be adopted? Unless there is a technical justification demonstrating why such a limitation is necessary, there should not be a maximum size. A size restriction would only serve to further limit the usefulness of the multi-nodal aggregation option and therefore is not responsive to FERC’s directive.

1. How should distribution factors be calculated? As a price taker and settlement-only resource that would not be bidding into the market by reacting to price signals in the market, it is not clear what the role of distribution factors would be. MISO should first provide additional clarification on the role of distribution factors before determining the best approach to their calculation.
2. Should a system wide limit be for multi-node aggregations be introduced? Similar to the maximum size, without technical justification, an arbitrary system-wide limit should not be introduced. There is no precedent for such a limitation, so this is not responsive to FERC’s directive.

Advanced Energy United appreciates the opportunity to provide these comments and looks forward to continuing to work with MISO to explore options to facilitate meaningful opportunities for multi-node aggregations. Please reach out to Lisa Barrett with any questions.

Respectfully submitted,

Lisa Barrett

315-382-7238

lbarrett@advancedenergyunited.org

[i] Participation of Distributed Energy Res. Aggregations in Mkts. Operated by Reg’l Transmission Orgs. & Indepe. Sys. Operators, Order No. 2222, 172 FERC ¶ 61,247 (2020), order on reh’g, Order No. 2222-A, 174 FERC ¶ 61,197, order on reh’g, Order No. 2222-B, 175 FERC ¶ 61,227 (2021) (hereafter “Order No. 2222, Order No. 2222- A, Order No. 2222-B”), at P130.

[ii] PJM Interconnection, L.L.C., Order No. 2222 Compliance Filing, Docket No. ER22-962-005 (Sept. 1, 2023) at 19-21.

DERTF: Multi-Node Aggregation Proposal  

The referenced slide deck is posted at:  https://cdn.misoenergy.org/20240212%20DERTF%20Item%2004d%20Multi-node%20Aggregations%20(MSC-2019-2)631741.pdf  

Entergy Feedback on MISO’s Multi-Node Aggregation Proposal  

February 26, 2024  

MISO’s initial Order 2222 Compliance filing proposed a single node aggregation model, which FERC directed MISO to support with technical justification “beyond congestion management” or “propose alternative locational requirements that are as geographically broad as technically feasible.”  FERC further directed MISO to provide a detailed technical explanation for the geographic scope of the alternate locational requirements, if such a limitation is proposed.  

At the February 12, 2024 DERTF, MISO presented explorational concepts in consideration of adding a multi node model to the single node model included in MISO’s initial filing to address FERC’s directive, and requested input on design questions relating to its straw proposal for Multi-Node Aggregation for DERs if it is adopted. 

While MISO did not request feedback on the overall concept of adding a multi-node model to the current single node model, for the reasons MISO limited aggregations to a single node participation model in its initial Order 2222 compliance filing, Entergy would prefer that MISO focus on providing support for the single node limitation, rather than pursuing development of a multi-node model that would be even more complex to manage and administer than Aggregations of DERs participating in MISO’s Markets behind a single node.  In support of maintaining and defending the Single Node participation model: 

• Entergy notes that Market Participation by DER Aggregators is not permitted by the majority of RERRAs in MISO, and thus MISO’s Load Serving Entities (LSEs) and Electric Distribution Companies (EDC) have not had much exposure to managing participation of these assets and do not have the experience needed to assess the administrative or operational processes that will be needed to manage Wholesale Market Participation by these assets.   
• In consideration of FERCs directive to propose alternative locational requirements, MISO should consider that the lack of experience and anticipation of complexity in managing these assets is largely why MISO’s members encouraged a single-node participation model in MISO’s initial compliance filing.   

Entergy encourages MISO to seek feedback from stakeholders regarding their support for providing technical justifications for the single-node option rather than adding a multi-node option.     

If MISO does pursue a multi-node aggregation model, limitations on participation must reflect:  

1. the limited time for EDCs and RERRAs to perform reliability and eligibility reviews,  
2. the potential for a lack of sufficient reliability review to have adverse reliability impacts on the BES and the likelihood of the complexity of multi-node aggregations to increase reliability risk by spreading risks associated with lack of visibility into real-time dispatch conditions or in the case of demand-response resources, non-performance of resources included in the aggregation; and 
3. the need for LSEs to be able to validate performance and settlements of distribution-connected assets to ensure that the loads they serve have received the services for which they are billed.   
4. The need for MISO to be able to effectively resolve disputes between Aggregators and EDCs/LSEs/LBAs 

With these considerations in mind, Entergy provides the feedback below on elements of the multi-node aggregation model presented by MISO and the related questions on which MISO has requested Stakeholder input.    

MISO’s Multi-node model straw proposal design elements (see slide 5)  

• Adding a multi node alternative specific to DER Aggregations 

Entergy agrees that any “multi-node” aggregations should be limited to Aggregations, but to avoid the operational and administrative complexity and the potential for adverse system impacts, we would suggest limiting the aggregations for which this option is available to energy offers only, and not available for demand response assets. 

• Price taker only  

As Entergy understands this proposal, if the aggregation is offered into DA or RT markets it will be selected by MISO and paid the LMP at the clearing price and would not be “dispatched” by MISO; rather, these assets would manage themselves and provide meter data to MISO for settlement purposes. 

• • More focused discussion is needed to understand how MISO would manage the selection of these assets without compromising system reliability if they are “price takers” and are automatically selected in the market. 

• Settlement only  

As Entergy understands this element of MISO’s proposal, the Aggregator would manage the assets included in the Aggregation in accordance with their offers and provide meter data to MISO for settlement, which requires a signed MDMA who attests to the validity of the data submitted. 

• • For purposes of assessing potential reliability impacts of assets being managed by an Aggregator, rather than MISO, the EDC would need to visibility into how the Aggregator planned to dispatch the assets included in the aggregation. 
  • For purposes of LSE performance and settlement validation, more focused discussion is needed to understand how the aggregated meter data would be reported relative to the node at which each of the assets participating in the aggregation were dispatched by the aggregator, in particular if the assets are price takers, and therefore automatically selected.    

• Limit to Local Balancing Authority Area and single Load Serving Entity 

• • The same size thresholds that apply to single-node aggregations should continue to apply to each node included in an aggregation with assets registered at multi-nodes. 
  • Participation in an aggregation should be limited to both a single LBA and a single LSE. 
    • One LBA may often contain multiple LSEs, and allowing Aggregations to cross LBAs, beyond single LSEs, would complicate the predictability of the assets within the aggregation to provide the services needed at a particular location as well as settlements and performance validation by LSEs. 
    • LSEs are responsible for performance validation and ultimately ensuring that their customers receive the services for which they are billed. 

• Must enroll individual DER 

Entergy supports including a requirement to enroll individual DERs, as the impact and eligibility of each DER will need to be assessed individually and modeling data is needed to for proper planning and operations where installed DER are participating in Wholesale Markets. 

• • Visibility of the capacity that may be dispatched by MISO at each node where the aggregation is registered is needed. 
  • Each node will have its own consideration regarding the number and size of DER assets that can be reliably interconnected and dispatched based on MISO’s dispatch orders.   
  • The number and size of resources included in an aggregation will also increase the potential for the aggregation to have a bigger impact on that node, and thus be limited by the reliability study.   

If multi-node model is added, MISO should consider the following in its design: 

• Should a maximum size be adopted?  

There should be a limit on both the number of nodes that can be included in an aggregation as well as the total MW, the MW per node, and the number of individual assets per node.  These limits are needed to address the concerns identified above relating to the need to limit the aggregation to a single LBA and a single LSE. 

• • More discussion is needed to determine what nodal and system-wide limits would be practical and how and by whom they would be established. 
• How should distribution factors be calculated?  

Entergy understands that in terms of a multi-nodal aggregation model, distribution factors would be used to generate an LMP for payments to the resources for the services provided where the services are rendered in multiple nodes with different LMPs.  Entergy requests that MISO include a description of what the Distribution Factor is used to determine in the next discussion on alternatives under consideration.   

• Should a system wide limit for multi-node aggregations be introduced?  

A minimum amount of NERC Registered transmission connected core generating resources that are tested and have proper communication is needed to maintain system reliability.  This number should be based on a ratio that considers load levels, and levels of load on the transmission system at which reliability may be seen.   

• • More discussion is needed on how and by whom this minimum amount should be determined. 
• Do you have any additional design questions that MISO should consider?  
  • Visibility is key to maintaining reliability, and the same data that is available in real time operations should be used in performance validation and settlements.  A commonly accessible data source should be considered for all phases of participation of DER Aggregations. 

• • As Entergy understands the model, DERs would sit at the distribution level, and so from a MISO energy market perspective would roll up under a load commercial pricing node. By having the DER offer in as a price taker and then submitting meter data, the assumption would be that much less load was consumed at that point and the DER would get paid the load LMP for “generating” energy. 
    • If MISO does not have visibility into DERs on the distribution level, they would be prone to overcommit generation resources, adding risk towards inefficient markets versus reliability. This would also affect the LSE’s if they are not aware of what DERs may or may not be utilized when bidding in their daily demand offers. 

• • Allowing aggregations outside of a single RERRA area would significantly complicate MISO’s proposed Dispute Resolution process for performance validation and settlements. 

Ultimately, MISO’s primary concern as the Reliability Coordinator for the MISO system is maintaining system reliability, and considerations relating to reliability concerns should be deferred to the Reliability Subcommittee for further discussion.  Similarly, questions relating to reliably planning for these assets to interact with the BES should be deferred to the Planning Subcommittee.