UNITED STATES OF AMERICA 

FEDERAL ENERGY REGULATORY COMMISSION 

18 CFR Part 35 

(Docket No. RM05-4-001; Order No. 661-A) 

Interconnection for Wind Energy 

(Issued December 12, 2005) 

AGENCY: Federal Energy Regulatory Commission 

ACTION: Order on Rehearing and Clarification 

SUMMARY: The Federal Energy Regulatory Commission is granting in part and 

denying in part the requests for rehearing and clarification of its Final Rule on 

Interconnection for Wind Energy, Order No. 661. Order No. 661 requires public utilities 

that own, control, or operate facilities for transmitting electric energy in interstate 

commerce to append to their standard large generator interconnection procedures and 

large generator interconnection agreements in their open access transmission tariffs 

standard procedures and technical requirements for the interconnection of large wind 

generation. 

EFFECTIVE DATE: Changes made to Order No. 661 in this order on rehearing and 

clarification will become effective on [insert date 30 days after publication in the Federal 

Register]. 

FOR FURTHER INFORMATION CONTACT: 
Docket No. RM05-4-001 -- 2 -- 

Bruce A. Poole (Technical Information) 

Office of Markets, Tariffs and Rates 

Federal Energy Regulatory Commission 

888 First Street, N.E. 

Washington, DC 20426 

(202) 502-8468 

G. Patrick Rooney (Technical Information) 

Office of Markets, Tariffs and Rates 

Federal Energy Regulatory Commission 

888 First Street, N.E. 

Washington, DC 20426 

(202) 502-6205 

P. Kumar Agarwal (Technical Information) 

Office of Markets, Tariffs and Rates 

Federal Energy Regulatory Commission 

888 First Street, N.E. 

Washington, DC 20426 

(202) 502-8923 

LaChelle Brooks (Technical Information) 

Office of Markets, Tariffs and Rates 

Federal Energy Regulatory Commission 

888 First Street, NE 

Washington, DC 20426 

(202) 502-6522 

Jeffery S. Dennis (Legal Information) 

Office of the General Counsel 

Federal Energy Regulatory Commission 

888 First Street, N.E. 

Washington, DC 20426 

(202) 502-6027 

SUPPLEMENTARY INFORMATION

:
UNITED STATES OF AMERICA 

FEDERAL ENERGY REGULATORY COMMISSION 

Before Commissioners: Joseph T. Kelliher, Chairman; 

 Nora Mead Brownell, and Suedeen G. Kelly. 

Interconnection for Wind Energy Docket No. RM05-4-001 

ORDER NO. 661-A 

ORDER ON REHEARING AND CLARIFICATION 

(Issued December 12, 2005) 

1. On June 2, 2005, the Commission issued Order No. 661, the Final Rule on 

Interconnection for Wind Energy (Final Rule).1

 Several entities have filed timely 

requests for rehearing and clarification of the Final Rule.2

 In this order, the Commission 

grants in part and denies in part the requests for rehearing and clarification. 

I. Background

2. In Order No. 2003,3

 the Commission adopted standard procedures and a standard 

 1

 Interconnection for Wind Energy, Order No. 661, 70 FR 34993 (June 16, 2005), 

FERC Stats. & Regs. ¶ 31,186 (2005) (Final Rule); see also Order Granting Extension of 

Effective Date and Extending Compliance Date, 70 FR 47093 (Aug. 12, 2005), 

112 FERC ¶ 61,173 (2005). 

2

 Those entities requesting rehearing and/or clarification, and the acronyms used to 

refer to them in this order, are listed in Appendix A to this order. 

3

 Standardization of Generator Interconnection Agreements and Procedures, Order 

No. 2003, 68 FR 49845 (Aug. 19, 2003), FERC Stats. & Regs., Regulations Preambles 

¶ 31,146 (2003) (Order No. 2003), order on reh’g, 69 Fed. Reg. 15,932 (Mar. 24, 

2004), FERC Stats & Regs., Regulations Preambles ¶ 31,160 (2004) (Order No. 2003-A), 

(continued) 
Docket No. RM05-4-001 -2- 

 

agreement for the interconnection of large generation facilities. The Commission 

required public utilities that own, control, or operate facilities for transmitting electric 

energy in interstate commerce to file revised Open Access Transmission Tariffs (OATTs) 

containing these standard provisions, and use them to provide interconnection service to 

generating facilities having a capacity of more than 20 megawatts. 

3. In Order No. 2003-A, on rehearing, the Commission noted that the standard 

interconnection procedures and agreement were based on the needs of traditional 

generation facilities and that a different approach might be more appropriate for 

generators relying on other technologies, such as wind plants.4

 Accordingly, the 

Commission granted certain clarifications, and also added a blank Appendix G to the 

standard Large Generation Interconnection Agreement (LGIA) for future adoption of 

requirements specific to other technologies.5

4. The Commission issued a Notice of Proposed Rulemaking (NOPR) that proposed 

technical standards applicable to the interconnection of large wind generating plants6

 to 

order on reh’g, 70 Fed. Reg. 265 (January 4, 2005), FERC Stats & Regs., Regulations 

Preambles ¶ 31,171 (2004) (Order No. 2003-B), order on reh’g, 70 FR 37661 (June 30, 

2005), FERC Stats. & Regs. ¶ 31,190 (2005) (Order No. 2003-C); see also Notice 

Clarifying Compliance Procedures, 106 FERC ¶ 61,009 (2004). 

4

 Order No. 2003-A at P 407, n.85. 

5

 Id. 

6

 Large wind generating plants are those with an output rated at more than 20 MW 

at the point of interconnection. The interconnection requirements for small generators 

rated at 20 MW or less are set forth in Standardization of Small Generator 

(continued) 
Docket No. RM05-4-001 -3- 

 

be included in Appendix G of the LGIA.7

 We proposed the standards in light of our 

findings in Order No. 2003-A noted above and in response to a petition submitted by the 

American Wind Energy Association (AWEA).8

 Specifically, the Commission proposed 

to establish uniform standards in Appendix G that would require large wind plants 

seeking to interconnect to the grid to: (1) demonstrate low voltage ride-through 

capability; in other words, show that the plant can remain on line during voltage 

disturbances up to specified time periods and associated voltage levels; (2) have 

supervisory control and data acquisition (SCADA) capability to transmit data and receive 

instructions from the Transmission Provider; and (3) maintain a power factor within the 

range of 0.95 leading to 0.95 lagging, measured at the high voltage side of the substation 

transformers. The Commission proposed to permit the Transmission Provider to waive 

the low voltage ride-through requirement on a comparable and not unduly discriminatory 

basis. We proposed to permit the Transmission Provider to waive or defer compliance 

with the power factor requirement where it is not necessary. The Commission did not 

Interconnection Agreements and Procedures, Order No. 2006, 70 FR 34190 (June 13, 

2005), FERC Stats. & Regs. ¶ 31,180 (2005), reh'g pending. 

7

 See Interconnection for Wind Energy and Other Alternative Technologies,

Notice of Proposed Rulemaking, 70 FR 4791 (Jan. 31, 2005), 110 FERC ¶ 61,036 (2005) 

(NOPR). 

8

 See Petition for Rulemaking or, in the Alternative, Request for Clarification of 

Order No. 2003-A, and Request for Technical Conference of the American Wind Energy 

Association (May 20, 2004), filed in Docket Nos. RM02-1-005 and PL04-15-000 

(AWEA Petition). 
Docket No. RM05-4-001 -4- 

 

propose to adopt a proposal by AWEA to allow a wind generator to “enter the 

interconnection queue and conduct its own Feasibility Study, having obtained the 

information necessary to do so upon paying the initial deposit and submitting its 

interconnection application” (referred to as “self-study” provisions).9

 The Commission 

did, however, ask for comments on how to balance the need of wind generators to obtain 

certain data from the Transmission Provider before completing their Interconnection 

Requests with the need to protect critical energy infrastructure information and 

commercially sensitive data against unwarranted disclosure. 

5. In the Final Rule, the Commission adopted final standard procedures and technical 

requirements for the interconnection of large wind plants in Appendix G, and required all 

public utilities that own, control, or operate facilities for transmitting electric energy in 

interstate commerce to append Appendix G to the Large Generator Interconnection 

Procedures (LGIPs) and LGIAs in their OATTs. As described in more detail below, the 

Commission adopted provisions establishing standards for low voltage ride-through and 

power factor design criteria, and requiring that wind plants meet those standards if the 

Transmission Provider shows, in the System Impact Study, that they are needed to ensure 

the safety or reliability of the transmission system. Additionally, the Appendix G 

adopted by the Commission included a SCADA requirement applicable to all wind 

9

 See AWEA Petition at 13. 
Docket No. RM05-4-001 -5- 

plants. Finally, as described in more detail below, the Commission adopted in Appendix 

G to the LGIP limited special interconnection procedures applicable to wind plants. 

II. Requests for Rehearing and Clarification and Commission Conclusions

 A. Low Voltage Ride-Through Provisions

6. In the Final Rule, the Commission adopted a low voltage ride-through standard, 

but provided that a wind plant is required to meet the standard only if the Transmission 

Provider shows, in the System Impact Study, that low voltage ride-through capability is 

needed to ensure safety or reliability. The standard (adopted in Figure 1 of Appendix G 

to the LGIA), if applicable, requires the wind plant to stay online for specified time 

periods and at associated voltage levels where there is a disturbance on the transmission 

system. The Final Rule requires that the required voltage levels be measured at the Point 

of Interconnection. 

7. Several entities requested rehearing of various aspects of the low voltage ridethrough requirement and standard included in the Final Rule, including: (1) provisions 

that require low voltage ride-though only when the System Impact Study shows that such 

capability is necessary for safety or reliability; (2) the specific low voltage ride-through 

standard adopted in the Final Rule; (3) the point of measurement for the standard; and 

(4) arguments that Transmission Providers should be permitted to adopt other provisions 

of the German low voltage ride-through standard (which the Commission referenced in 

the Final Rule). 

8. However, as described in more detail below, NERC and AWEA jointly requested 
Docket No. RM05-4-001 -6- 

that the Commission delay the effective date of the Final Rule to give them time to 

resolve concerns expressed by NERC regarding the low voltage ride-through provisions. 

The Commission granted this extension, and on September 19, 2005, NERC and AWEA 

submitted a joint report with recommended revisions. 

1. Case-by-Case Application/Burden of Proof for Applying the

Low Voltage Ride-Through Standard

9. Prior to the NERC/AWEA joint report, several entities objected on rehearing to 

the Final Rule’s adoption of a low voltage ride-through requirement on a case-by-case 

basis, placing the burden of proof on the Transmission Provider to show that low voltage 

ride-through capability is needed. ATC, EEI, NERC, NRECA/APPA, and SCE, among 

others, urged the Commission to return to the approach in the NOPR, which would have 

required low voltage ride-through for all wind plants unless waived by the Transmission 

Provider on a not unduly discriminatory basis. ATC noted that interconnection studies 

only consider a snapshot of the transmission system, and do not take into account 

changes in the future that may cause a need for low voltage ride-through capability to 

ensure reliability. ATC, as well as EEI and SCE, argued that under the case-by-case 

approach adopted in the Final Rule, Transmission Providers will need to perform 

additional analyses to determine if a reliability need will exist over the life of the wind 

plant. SCE, for example, noted that while a particular System Impact Study may not 

conclusively demonstrate that low voltage ride-through is needed at that time, if other 

generation projects are built, the first wind plant may come to need low voltage ride-
Docket No. RM05-4-001 -7- 

 

through. According to various entities, the additional analyses needed to take these 

scenarios into account will increase the time, cost and complexity of wind plant 

interconnections and could be a barrier to their development.10 

10. Furthermore, ATC asserted that the case-by-case approach imposes the 

responsibility for resolving reliability concerns that arise in the future on the 

Transmission Provider because wind generating plants cannot be retrofitted with low 

voltage ride-through capability. Similarly, NRECA/APPA argued that this approach 

unduly discriminates in favor of wind plants in that low voltage ride-through capability 

may not be “necessary” (and therefore required) for a specific plant because other 

generators or Transmission Providers can “make up the difference.”11 ATC also 

contended that the case-by-case approach may require the Transmission Provider to incur 

capital costs that should have been incurred by the wind plant. 

11. EEI and NU argued that the case-by-case approach adopted by the Commission in 

the Final Rule “lowers the bar for reliability.”12 NERC similarly asserted that requiring 

Transmission Providers to justify common elements of good utility practice on a case-by10 New York ISO asserts that the case-by-case approach could lead to acute 

problems in New York, where it has received interconnection applications from wind 

plants totaling over 5000 MW of generation. According to New York ISO, conducting 

case-by-case reviews for each of these projects could greatly complicate the study 

process and result in substantial delays. 

11 Request for Rehearing of NRECA/APPA at 6. 

12 Request for Rehearing of EEI at 8. 
Docket No. RM05-4-001 -8- 

 

case basis is unwise and may deter Transmission Providers from implementing and 

following good utility practice.13 Southern Company states that the Transmission 

Provider, as the entity responsible for maintaining reliability, should not bear the burden 

of proof to establish what is required to maintain system reliability. Southern Company 

states that it supports the Commission’s statement that Transmission Providers should not 

be permitted to require wind plants to install costly equipment that is not needed for 

reliability, but argues that the burden of proof should be shifted, and the System Impact 

Study should establish that such equipment is not required. Also, NRECA/APPA argued 

that the case-by-case approach imposes unreasonable reliability risks, and effectively 

voids the requirement that wind plants have low voltage ride-through capability “in a 

broad range of circumstances.”14

12. Those requesting rehearing raised several other arguments regarding the case-bycase approach and burden of proof for applying the low voltage ride-through standard. 

NERC believed that the case-by-case approach could unintentionally create a 

“patchwork” of varying requirements. EEI and NU also suggested that requiring a 

showing of need may introduce prolonged uncertainties into the interconnection process 

if parties disagree as to the study assumptions. SCE asserted that rather than limiting 

opportunities for undue discrimination, the requirement of a showing of need could result 

13 New York ISO states that it adopts NERC’s position on this issue. 

14 Request for Rehearing of NRECA/APPA at 6. 
Docket No. RM05-4-001 -9- 

in discriminatory treatment in areas with large amounts of wind generation because 

projects lower in the queue may be responsible for additional costs since the need for low 

voltage ride-through could not be demonstrated for earlier projects. EEI contended that 

Order No. 2003 already contains provisions allowing the parties to an interconnection to 

exercise their discretion in complying with system reliability obligations, and that there is 

no evidence of problems with these procedures that justifies such a significant departure 

from them in the Final Rule. Further, EEI argued that the Final Rule was a significant 

departure from the NOPR and that the Commission should not adopt it without providing 

an opportunity for comments on it. Finally, NRECA/APPA argued that the Commission 

has not explained how this approach is consistent with NERC and WECC standards. 

2. Specific Low Voltage Ride-Through Standard 

13. Certain requests for rehearing and clarification also addressed the specific low 

voltage ride-through standard adopted by the Commission in the Final Rule. In its 

request for rehearing, NERC asserted that the standard in Figure 1 of the Final Rule is not 

appropriate. More specifically, NERC contended that Figure 1, by allowing a wind plant 

to disconnect from the transmission system when the voltage drops below 15 percent of 

the nominal voltage, could result in violation of NERC Reliability Standard TPL-002-0. 

This standard requires transmission planners to ensure that the system will remain stable 

and within applicable thermal and voltage ratings, with no loss of demand or curtailment 

of firm transfers, where there is a normally cleared fault on a single element, which is 

typically four to eight cycles or 0.067 to 0.133 seconds (67 to 133 milliseconds). 
Docket No. RM05-4-001 -10- 

 

According to NERC, a fault occurring on a transmission line near a wind plant could 

cause the voltage at that point to drop to zero for this clearing time. NERC stated that 

because Figure 1 would allow the wind plant to disconnect when the voltage drops below 

15 percent of the nominal voltage, the loss of the single grid element (the transmission 

line) would be compounded by the loss of the real power (and any reactive power) 

produced by the wind plant. This “double contingency event” (loss of both the 

transmission line and wind plant) violates Reliability Standard TPL-002-0, NERC 

asserted. 

14. To remedy this problem, NERC requested that the Commission simply require 

wind plants to meet NERC and regional reliability council requirements.15 Alternatively, 

NERC argued that the rule should be modified to require wind plants to remain connected 

through a normally cleared single line to ground or three phase fault. Specifically, NERC 

asserted that Figure 1 should be altered to require a wind plant to remain online for 0.167 

seconds (167 milliseconds), or ten cycles, if voltage at the high side of the wind plant 

step-up transformer is reduced to zero. After 0.167 seconds (167 milliseconds), but 

before 0.625 seconds (625 milliseconds), NERC argued that Figure 1 should require the 

wind plant to stay connected as long at the voltage is at or above 15 percent of the 

15 ISO-NE argued that the Commission should have required wind plants to be 

subject to the same system performance standards that are applied to other generating 

technologies. 
Docket No. RM05-4-001 -11- 

 

nominal voltage. NERC contended that these modifications would reduce the risk to the 

reliability of the electric system to an acceptable level.16

15. Similarly, NU asserted that wind plants should be required to “remain on-line for 

all faults cleared by normal operation of all protective equipment unless clearing the 

fault . . . isolates the plant from the rest of the grid.”17 According to NU, this change 

would require generators to have low voltage ride-through capability down to zero 

percent of the nominal voltage at the Point of Interconnection. CenterPoint also contend 

that wind plants should be required to maintain low voltage ride-through capability down 

to zero percent of the rated line voltage 150 milliseconds (.150 seconds) (the time 

generally needed for the transmission system protective equipment to clear the fault). 

NU and CenterPoint argued that this change would reduce the likelihood that a low 

voltage event would escalate to a cascading outage or voltage collapse. NU also asserted 

that this requirement is similar to those applicable to other generators, and could be 

achieved by wind turbines that are currently available. NU stated that the standard 

adopted in the Final Rule would threaten reliability by allowing a wind plant to reduce 

output, or trip offline, simply due to a typical system fault. 

16 ISO-NE also suggested that, if the Commission adopted a low voltage ridethrough standard, it be modified to require the wind plant to be connected at zero voltage 

for “a time period associated with the typical clearing time of a normal design 

contingency fault.” Request for Rehearing of ISO-NE at 4. 

17 Request for Rehearing of NU at 5. 
Docket No. RM05-4-001 -12- 

16. NRECA/APPA also objected to the low voltage ride-through standard adopted in 

the Final Rule. Specifically, they contended that the Final Rule should not have 

established the low voltage ride-through curve as an absolute standard, and instead 

should have permitted Transmission Providers to adopt an alternative curve (subject to 

review by the Commission if there is a dispute) when the System Impact Study shows 

that it is necessary. ISO-NE, going further, requested that if the Commission adopted a 

low voltage ride-through standard, it should be only a guideline for wind turbine 

manufacturers. NRECA/APPA asserted that the Final Rule did not conclude that the low 

voltage ride-through standard will protect reliability or address the technical concerns 

raised by comments, and, by stating that the Commission might consider an alternative 

low voltage ride-through standard, recognizes that it may not be adequate to preserve 

reliability in all circumstances. Alternatively, NRECA/APPA asked that the Commission 

clarify that Transmission Providers may support variations from the low voltage ridethrough curve in the Final Rule, based on local and subregional reliability conditions, 

under the three variation standards adopted in the Final Rule. 

17. EEI asserted that the technical challenges presented by wind generation are being 

considered by the industry worldwide, and that many international standards differ from 

the Commission’s Final Rule. Both EEI and SCE objected to the specific low voltage 

ride-through standard through comparison to the German interconnection guidelines. 

Particularly, EEI noted that the German grid code requires wind plants to remain 

connected to the grid following a fault that results in the voltage at the Point of 
Docket No. RM05-4-001 -13- 

Interconnection dropping to 15 percent of the nominal voltage for as long as 0.15 

seconds. According to EEI, revisions to the German grid code are nearing completion 

that will require wind plants to remain connected to the transmission system following a 

fault that drops the voltage at the Point of Interconnection to zero percent of the nominal 

voltage for as long at 0.15 seconds. Further, EEI reported that the Hydro-Québec 

requirements for wind farm interconnection are stricter than the Commission’s Final 

Rule; they require wind plants to ride through a fault resulting in a voltage drop to zero 

percent of nominal voltage for as long as 0.15 seconds. Finally, EEI noted that Ireland 

requires wind plants to stay online after a fault that drops the voltage to 15 percent of 

nominal voltage for as long as 0.15 seconds. SCE additionally asserted that the 

requirement that low voltage ride-through be shown to be necessary in the System Impact 

Study conflicts with the German wind interconnection guidelines because those 

guidelines assume that all generation will meet the low voltage ride-through standard. 

SCE stated that the Final Rule should adopt low voltage ride-through capability as a 

governing standard, with exceptions approved by the governing technical body (NERC or 

the Western Electricity Coordinating Council (WECC), a regional reliability council), as 

in the German standard. 

18. In the Final Rule, the Commission stated that “the low voltage ride-through 

requirement, and the time periods and associated voltage levels set forth in Appendix G, 

Figure 1, apply to three-phase faults.” ATC sought clarification as to whether the low 

voltage ride-through requirement applied only to three-phase faults. Assuming that is the 
Docket No. RM05-4-001 -14- 

case, ATC asked whether there was a requirement for single-phase and double-phase 

faults. 

3. Point of Measurement for the Low Voltage Ride-Through 

Standard

19. NERC argued on rehearing that because the Point of Interconnection may be some 

distance from a wind plant, the plant might actually disconnect at voltages higher than 

15 percent of the nominal voltage at the high side of the wind plant step-up transformer. 

According to NERC, this could create a further risk of a double contingency event.18 

To avoid this risk, NERC contended that low voltage ride-through capability should be 

measured at the high voltage terminal of the wind plant step-up transformer. Southern 

Company stated that a revision to section A.i.2 of the LGIA Appendix G was necessary 

to reflect the Commission’s decision in the Final Rule to adopt the Point of 

Interconnection as the measurement point. 

4. Adoption of Other Provisions from the German Standards

20. SCE noted that while the Final Rule adopted a low voltage ride-through standard 

based on the German wind interconnection guidelines, the Commission did not adopt the 

related requirements in the German guidelines. It noted several provisions of the German 

guidelines that it stated go hand-in-hand with the low voltage ride-through standard.19 

 18 See supra, P 13. 

19 See Request for Rehearing and Clarification of SCE at 9-10.
Docket No. RM05-4-001 -15- 

SCE asked the Commission to clarify that Transmission Providers may implement these 

other guidelines in the German standard. 

5. NERC/AWEA Recommended Revisions to Low Voltage RideThrough Provisions

21. As noted above, NERC filed a request for rehearing of the Final Rule contending, 

in part, that the specific low voltage ride-through standard adopted by the Commission 

would permit violations of a NERC system performance standard.20 On August 4, 2005, 

NERC and AWEA filed a request to extend the effective date of the Final Rule to allow 

for discussions to resolve the reliability concerns expressed by NERC. They committed 

to submitting to the Commission a joint final report on their discussions. On August 5, 

2005, the Commission issued an order granting this request.21

22. On September 19, 2005, NERC and AWEA submitted their joint final report, 

which recommended revisions to the low voltage ride-through provisions of the Final 

Rule. They state that the recommended revisions are supported by the NERC Planning 

Committee and AWEA members. NERC states that the concerns expressed in its request 

for rehearing will be resolved if the Commission adopts the recommended revisions. 

23. Specifically, NERC and AWEA recommend a different low voltage ride-through 

 20 See supra, P 13. 

21 Interconnection for Wind Energy, 70 FR 47093 (Aug. 12, 2005), 112 FERC 

¶ 61,173 (2005). 
Docket No. RM05-4-001 -16- 

section to be inserted in Appendix G. The recommended provisions include a transition 

period standard, which would apply to wind plants that either: (a) have interconnection 

agreements signed and filed with the Commission, filed with the Commission in 

unexecuted form, or filed with the Commission as non-conforming agreements between 

January 1, 2006 and December 31, 2006, with a scheduled in-service date no later than 

December 31, 2007; or (b) involve wind turbines subject to a procurement contract 

executed before December 31, 2005 for delivery through 2007. During this transition 

period, wind plants would be required to ride through low voltage events down to 0.15 

per unit for normal clearing times up to a maximum of nine cycles. 

24. Following this transition period, the NERC/AWEA proposal would require wind 

plants to ride through low voltage events down to a zero voltage level for “locationspecific” clearing times up to a maximum of nine cycles. If the fault on the transmission 

system remained after this clearing time, the joint recommendation would permit the 

wind plant to disconnect from the system. 

25. Under the joint recommendation of NERC and AWEA, during both the transition 

period and after, low voltage ride-through capability would be required for all new wind 

plant interconnections, instead of only when the System Impact Study shows that such 

capability is needed for safety or reliability, as in the Final Rule. Additionally, in both 

cases the point of measurement for the requirement would be at the high side of the wind 

plant step-up transformer, instead of at the Point of Interconnection, as in the Final Rule. 

NERC and AWEA also recommend eliminating Figure 1 during both the transition 
Docket No. RM05-4-001 -17- 

period and after the transition period because the low voltage ride-through standard 

described in their Joint Report replaces the voltage trace represented by Figure 1. 

26. Finally, NERC and AWEA recommend limiting the variations to the low voltage 

ride-through provisions that were permitted by the Final Rule. The Final Rule permits 

Transmission Providers to justify variations between their pro forma tariff and the Final 

Rule Appendix G based on the regional reliability, the “consistent with or superior to,” or 

the independent entity variation standards in Order No. 2003.22 NERC and AWEA 

recommend that variations to their proposed low voltage ride-through provisions be 

permitted on an interconnection-wide basis only, reasoning that such a limitation is 

appropriate because the provisions are intended to satisfy a NERC reliability standard, 

and because wind generators could incur significant additional costs if they had to meet 

many different standards. NERC and AWEA note that limiting variations would not 

restrict the ability to request a deviation in a specific non-conforming agreement filed 

with the Commission (as opposed to a variation built into a pro forma tariff). 

27. The Commission issued notice of the NERC/AWEA joint report on September 21, 

2005, and provided interested parties with the opportunity to submit comments on or 

before October 3, 2005. FPL Energy, National Grid, New York ISO and PJM all filed 

comments supporting the technical recommendations in the joint report. 

28. National Grid also asks that the Commission make two clarifications. First, it asks 

 22 Final Rule at P 107, 109. 
Docket No. RM05-4-001 -18- 

the Commission to clarify that while the point of measurement for compliance with the 

low voltage ride-through standard would be at the high side of the step-up transformer, 

the point of measurement for reactive power would remain at the Point of 

Interconnection. Second, National Grid requests that the nine cycle maximum clearing 

time in the low voltage ride-through provision applies only to three-phase faults. It says 

that single line-to-ground faults are typically much longer than nine cycles, so a general, 

non-specified standard is more appropriate for such faults. 

29. New York ISO, while strongly supporting the technical aspects of the 

NERC/AWEA joint recommendations, urges the Commission to reject the proposal that 

variations to the low voltage ride-through provision be permitted only on an 

interconnection-wide basis or through individually-filed interconnection agreements. It 

argues that this could hamper efforts to preserve reliability in individual regions, and 

asserts that satisfying NERC planning standards is not sufficient to preserve reliability 

because New York State, as well as other regions, sometimes need more stringent 

reliability requirements than those of NERC. New York ISO says that the Commission 

has viewed NERC’s criteria as being minimum reliability requirements, which individual 

regions may exceed if necessary. Therefore, New York ISO argues that at a minimum, 

the Commission should permit independent entities to seek variations from the low 

voltage ride-through standards recommended by NERC and AWEA. 

30. Finally, New York ISO asks the Commission to clarify that, assuming the 

NERC/AWEA recommendations are adopted, the “filing date” for purposes of the 
Docket No. RM05-4-001 -19- 

proposed transition period includes the date that conforming interconnection agreements 

are fully and finally executed. New York ISO notes that executed conforming 

agreements need not be filed with the Commission. Therefore, it contends that the 

transition period should apply to agreements executed within its timeframe but not filed 

with the Commission. 

Commission Conclusion on Low Voltage Ride-Through Provisions

31. The Commission grants rehearing with regard to the low voltage ride-through 

provisions, and adopts the joint recommendation of NERC and AWEA without 

modification. This provides a standard that will ensure that wind plants are 

interconnected to the grid in a manner that will not degrade system reliability. 

Furthermore, this standard satisfies the reliability concerns expressed by NERC, and 

either satisfies or renders moot many of the rehearing requests described above, including 

those related to the case-by-case application of the low voltage ride-through standard and 

point of measurement for the low voltage ride-through standard. Additionally, the joint 

recommendation also responds to the arguments on rehearing of EEI and SCE regarding 

comparison to the German interconnection guidelines. 

32. We are eliminating Figure 1 from Appendix G because the standard we are 

adopting in Appendix G replaces that figure. Accordingly, all references to Figure 1 in 

the preamble to the Final Rule should be read to apply to the standard now described in 

Appendix G. 
Docket No. RM05-4-001 -20- 

33. We also adopt the NERC/AWEA proposal to permit variations to the low voltage 

ride-through provisions of Appendix G only on an interconnection-wide basis. The low 

voltage ride-through provisions we adopt in this order on rehearing were crafted 

specifically, after negotiation among the wind industry and NERC, to ensure that NERC 

Reliability Standard TPL-002-0 is met in all regions. While other interconnection 

standards may be more susceptible to variation among Transmission Providers or 

independent entities, the close connection of this standard to an industry-wide reliability 

standard persuades us that limiting variations to those made on an interconnection-wide 

basis will best ensure that reliability is protected. Accordingly, we reject SCE’s request 

that we clarify that Transmission Providers may implement other guidelines from the 

German interconnection standard. Adoption of other guidelines from the German 

standard on a Transmission Provider-specific basis could result in varying requirements 

that may not meet established reliability standards. For the same reasons, we also reject 

New York ISO’s assertion that the Commission should continue to permit variations to 

the low voltage ride-through provisions under the three variation standards in the Final 

Rule, and particularly the independent entity variation. We note, however, that under 

section 1211 of the Energy Policy Act of 2005, the State of New York “may establish 

rules that result in greater reliability within that State, as long as such action does not 

result in lesser reliability outside the State than that provided by the reliability 
Docket No. RM05-4-001 -21- 

 

standards.”23 Therefore, the Commission will consider proposed variations from the 

State of New York under this statutory provision. 

34. In response to the arguments of NRECA/APPA that the Final Rule should have 

permitted Transmission Providers to adopt alternative low voltage ride-through standards, 

and ISO-NE’s contention that the standard in the Final Rule should be only a guideline, 

we find that the definitive standard we adopt here will provide certainty to wind 

developers and manufacturers and ensure that reliability is maintained and NERC 

planning standards are met. If another standard is necessary for a specific wind plant 

interconnection to maintain reliability, a non-conforming agreement may be filed with the 

Commission. 

35. In response to ATC and National Grid, we clarify that the low voltage ridethrough provisions we are adopting apply to all types of faults, not just to three-phase 

faults. The standard refers to three-phase faults with normal clearing as well as single 

line to ground faults with delayed clearing. In response to National Grid’s specific 

concern, we clarify that the nine cycle maximum clearing time expressed in the low 

voltage ride-through provisions applies only to three-phase faults. Single line to ground 

faults have typically much longer clearing times, as National Grid notes, and the low 

voltage ride-through provisions adopted here recognize this difference by specifically 

23 Energy Policy Act of 2005, Pub. L. No. 109-58, § 1211, 119 Stat. 594, 945 

(2005). 
Docket No. RM05-4-001 -22- 

referring to “single line to ground faults with delayed clearing.” This non-specified 

standard is appropriate for those types of faults. 

B. Power Factor (Reactive Power) Provisions

36. In the Final Rule, the Commission adopted in Appendix G to the LGIA a power 

factor standard applicable to wind plants. The Final Rule provides that wind plants are 

required to meet this standard only if the Transmission Provider shows, in the System 

Impact Study, that reactive power capability is necessary to ensure the safety or reliability 

of the transmission system. The specific power factor standard in Appendix G to the 

LGIA, if applicable, requires a wind plant to maintain a power factor within the range of 

0.95 leading to 0.95 lagging (hereinafter +/- 0.95), to be measured at the Point of 

Interconnection. 

37. Requests for rehearing and/or clarification of these provisions concern whether 

wind plants should have to maintain a required power factor only where the System 

Impact Study shows that it is required for reliability or safety, and whether the power 

factor standard and point of measurement adopted by the Commission in the Final Rule 

are appropriate. 

1. Case-by-Case Application/Burden of Proof for Applying the 

Power Factor Standard

38. Several entities object to the provisions in the Final Rule that require wind plants 

to maintain the required power factor only when the Transmission Provider, in the 

System Impact Study, shows that it is necessary to ensure safety or reliability. NERC 
Docket No. RM05-4-001 -23- 

objects to this approach because it may deter Transmission Providers from implementing 

and following good utility practice and could create a “patchwork” of varying 

requirements. NU argues that this approach “lowers the bar for reliability,” and will add 

complexity, cost and delay to the generator interconnection process because 

Transmission Providers will be required to perform more studies to determine whether 

reactive power capability is necessary for reliability or safety. Southern Company states 

that the Transmission Provider, as the entity responsible for maintaining reliability, 

should not bear the burden of proof to establish what is required to maintain system 

reliability. It supports the Commission’s statement that Transmission Providers should 

not be permitted to require wind plants to install costly equipment that is not needed for 

reliability, but argues that the burden of proof should be shifted to the generator. 

39. NRECA/APPA notes that traditional generators are required to meet the power 

factor standard not because reactive power is needed in every case to preserve reliability, 

but instead because the transmission system is dynamic and requires flexibility over time 

to maintain reliability. They state that the need for reactive power in the future under a 

variety of operating conditions cannot be determined with perfect certainty in the System 

Impact Study. The case-by-case approach, they contend, grants an undue preference to 

wind plants, imposes risks to system reliability, and shifts costs to consumers and other 

generating plants. The risk to system reliability is that the Final Rule may only require a 

wind plant to provide reactive power after other wind plants have been installed without 

such capability, and that at that point the resources from that single plant may not be 
Docket No. RM05-4-001 -24- 

enough to protect the transmission system. NRECA/APPA also asserts that the case-bycase approach increases uncertainty, contrary to the Commission’s conclusion in the 

Final Rule, because each wind plant will face different requirements based on the 

outcome of the System Impact Study. Additionally, it contends that this approach creates 

more opportunities for discrimination because it would permit wind plants to be treated 

differently. 

40. ATC contends that the Commission has offered no guidance as to what power 

factor range would be acceptable if a reliability need is not identified (and thus reactive 

power is not required), and whether wind plants in this instance must operate within any 

particular reactive power operating band. Similarly, NU expresses concern that wind 

plants could operate at any power factor in the absence of a showing of need in the 

System Impact Study, and thus avoid a physical requirement for delivering power onto 

the transmission system. According to ATC, the rule could be interpreted to permit wind 

plants to operate at any power factor they choose. It claims that reactive power is needed 

for each generator, and that each generator should be obligated to operate within a range 

of power factors, regardless of whether the transmission system as a whole needs 

additional reactive power capability. ATC recommends that at a minimum, the 

Commission require all wind plants to meet a power factor range of 0.95 leading to 1.0 

(unity), and allow the Transmission Provider to require a range of 1.0 (unity) to 0.95 

lagging if the System Impact Study shows that there is a reliability need. 
Docket No. RM05-4-001 -25- 

Commission Conclusion

41. The Commission will not modify the Final Rule to require wind plants to meet the 

power factor standard without a showing by the Transmission Provider, through the 

System Impact Study, that it is needed for safety or reliability. The case-by-case 

approach to a reliability needs assessment adopted in the Final Rule will not threaten 

reliability, as several of those seeking rehearing argue. As we noted in the Final Rule, if 

reactive power is necessary to maintain the safety or reliability of the transmission 

system, the System Impact Study performed by the Transmission Provider will establish 

that need.24 We stated in the Final Rule, and reiterate here, that the System Impact Study 

is the appropriate study for determining whether reactive power capability is needed.25 

Furthermore, we reasoned in the Final Rule that requiring wind plants to maintain the 

power factor standard only if the System Impact Study shows it to be necessary will not 

only ensure that increased reliance on wind power will not degrade system safety or 

reliability, but also will limit opportunities for undue discrimination by ensuring that 

Transmission Providers do not require costly equipment that is not necessary for 

reliability.26 

 24 Final Rule at P 51. 

25 Id. 

26 Id. 
Docket No. RM05-4-001 -26- 

42. NERC states that the decision in Order No. 661 to use a case-by-case approach 

may deter Transmission Providers from following Good Utility Practice, and may have 

the unintended consequence of spawning a patchwork of varying requirements. We 

agree with NERC that Transmission Providers must follow Good Utility Practice when 

interconnecting all generating plants, including wind plants, and that not following Good 

Utility Practice when performing System Impact Studies could lead to problems. 

However, the Commission points out that every Transmission Provider is required under 

Order No. 2003 to follow Good Utility Practice. Transmission Providers are required to 

complete a detailed System Impact Study, and are required to ensure that NERC 

reliability standards are met in all instances. This includes performing studies to 

determine what is necessary to ensure that the interconnection of a wind generating 

facility does not degrade grid reliability. The Commission recognizes that the industry 

(and particularly NERC) is continuing to address technical issues involved in the 

interconnection of wind plants. If NERC through its stakeholders and Board approval 

process develops a new standard, the Commission will entertain such a standard. Finally, 

we disagree with NRECA/APPA’s suggestion that the Final Rule threatens the reliability 

of the transmission system because it may require only wind plants later in the queue to 

provide reactive power, which may not be sufficient to protect the grid. The System 

Impact Study will take into account the system’s need for reactive power, both as it exists 

today and under reasonable anticipated assumptions. NRECA/APPA has not explained 

how assessing the need for reactive power through the System Impact Study process will 
Docket No. RM05-4-001 -27- 

result in too little reactive power being available in the future. Whenever a new generator 

is added to its system, the Transmission Provider must complete a new System Impact 

Study to ensure that reliability requirements are met; this may require a new wind 

generator later in the queue to meet the reactive power requirement. 

43. We also reject arguments that the case-by-case approach is inappropriate because 

of the dynamic nature of the transmission system. The fact that the transmission system 

is constantly changing is not new or unique to the study of wind plant interconnections. 

The studies that are part of the interconnection process should take into account likely 

circumstances that could occur on the Transmission Provider’s system, whether the 

studies are conducted in connection with a proposed wind plant or another type of 

generating facility. 

44. Furthermore, we are not persuaded that the approach adopted in the Final Rule 

will result in additional studies, increased costs and delays, and cost shifts. First, as noted 

previously, the System Impact Study, as well as the other interconnection studies, should 

take into account a variety of assumptions concerning anticipated transmission system 

conditions. If additional or expanded studies are needed to determine whether the power 

factor standard is necessary, the Commission does not believe that the additional burden 

will outweigh the cost considerations underlying the case-by-case approach. Finally, 

although the case-by-case approach may result in some delay, we remind the parties to a 

wind plant interconnection, like other interconnections, that they are still required to meet 

the milestones set forth in the LGIP. Any increased costs from completing expanded or 
Docket No. RM05-4-001 -28- 

additional studies within the timeframe required by this rule will be borne by the wind 

plant Interconnection Customer, as provided in Order No. 2003, which will leave other 

generators and the Transmission Provider unharmed. 

45. The Commission also rejects arguments that the case-by-case approach provides 

more opportunities for discrimination. As we noted in the Final Rule Appendix G was 

adopted to take into account the technical differences between wind plants and traditional 

generating plants. One of these differences is that for wind plants, reactive power 

capability is a significant added cost, while it is not a significant additional cost for 

traditional generators. Given these technical differences, treating wind plants differently 

with regard to reactive power requirements is not unduly discriminatory or preferential. 

Additionally, we note that the outcome of the System Impact Study, which determines 

whether reactive power will be required, can be challenged, which will serve to minimize 

the opportunities for discrimination by the Transmission Provider. Also, the wind plant 

Interconnection Customer will have recourse to the Commission if it believes the 

Transmission Provider has acted in a discriminatory manner. 

46. The Commission declines to adopt ATC’s request that all wind plants, at a 

minimum, operate within a power factor range of 0.95 leading to 1.0 (unity). This 

requirement would essentially require reactive power in every case, which we have 

already rejected. If reactive power capability is needed, including a power factor range of 

0.95 leading to 1.0 (unity), the System Impact Study will demonstrate this need. 
Docket No. RM05-4-001 -29- 

2. Specific Power Factor Standard

47. NRECA/APPA argues that the Commission should clarify that wind generators 

must meet the same reactive power requirements as other generators, provided the 

requirements are imposed in a nondiscriminatory manner. It notes that some 

Transmission Providers impose a power factor range wider that +/- 0.95 on all new 

generation, and argues that in such cases, the same range should be applied to wind 

plants. It argues that not imposing the same range threatens reliability and shifts the costs 

of preserving reliability to customers or competing generators. 

48. EEI and NU assert that wind plants should regulate voltage to a set point 

established by the Transmission Provider, as do synchronous generators. EEI contends 

that the language it offered in its initial comments would provide this necessary clarity, 

while also maintaining the flexibility provided in Order No. 2003 so that individual, sitespecific conditions may be addressed.27 NU states that wind turbines have this 

capability, either inherently (doubly fed induction generators) or through external 

equipment. 

49. NRECA/APPA also expresses concern that the phrase “taking into account any 

limitations due to voltage level, real power output, etc.” in the power factor requirements 

 27 EEI’s March 2, 2005 comments in this proceeding suggest that we require the 

wind plant to maintain a power factor within the range specified by the Transmission 

Provider “from time to time,” but would not require that it operate outside of the 0.95 

leading to 0.95 lagging range. See Comments of EEI (March 2, 2005) at 5-6. 
Docket No. RM05-4-001 -30- 

section of Appendix G could create operational problems for Transmission Providers 

with wind plants on their systems. Specifically, it is concerned that this language could 

exempt wind plants from their reactive power requirements during startup and low output 

periods, which could degrade reliability during a system contingency. 

Commission Conclusion

50. With regard to NRECA/APPA’s request for clarification that wind generators 

must meet a wider power factor range because some Transmission Providers impose a 

power factor range wider that +/- 0.95 on all new generation, we note that if we were to 

allow the Transmission Provider to impose a wider power factor range as a matter of 

routine, that would defeat the purpose of adopting a reactive power standard for wind 

generators. However, we note that if the System Impact Study shows the need for a 

power factor range wider than +/- 0.95 for safety or reliability, the Transmission Provider 

must file a non-conforming agreement, as Order No. 2003 permits. The Commission will 

consider these non-conforming agreements on a case by case basis. If a Transmission 

Provider has a different power factor range in its LGIA and wishes to apply that same 

range in Appendix G, it may seek a variation from the Commission under the variation 

standards approved in the Final Rule.28 We remind Transmission Providers, however, 

that the Commission has adopted a specific power factor standard for wind plants 

because of their technical differences. Any proposed variations will be viewed in light of 

 28 Final Rule at P 109. 
Docket No. RM05-4-001 -31- 

these technical differences. 

51. In response to the assertion of EEI and NU that wind plants should regulate 

voltage to a set point established by the Transmission Provider, we note that in the Final 

Rule we concluded that article 9.6.2 of the LGIA (which applies to all plants, including 

wind plants) already requires that the “Interconnection Customer . . . operate the Large 

Generating Facility to maintain the specified output voltage or power factor at the Point 

of Interconnection.”29 

52. Finally, the Commission addressed in the Final Rule the concerns raised by 

NRECA/APPA regarding the phrase “taking into account any limitations due to voltage 

level, real power output, etc.” We stated that this language was necessary due to the 

technical limitations of wind generating technology.30 We noted that all wind generating 

equipment vendors cannot meet the required power factor range at all levels of output. 

We reiterate that these technical differences make the disputed language necessary. 

Furthermore, without this language, a Transmission Provider could discriminate against a 

wind plant by requiring that it operate at the stated power factor at voltages where it is 

technically infeasible to do so. 

3. Point of Measurement of Power Factor

53. National Grid asks that if the Commission adopts the recommended revisions to 

 29 Id. at P 55. 

30 Id. at P 56. 
Docket No. RM05-4-001 -32- 

the low voltage ride-through provisions filed jointly by AWEA and NERC, it clarify that 

while the point of measurement for compliance with the low voltage ride-through 

standard would be at the high-side of the step-up transformer, the point of measurement 

for reactive power is at the Point of Interconnection. 

Commission Conclusion

54. We clarify that the point of measurement for the reactive power standard is at the 

Point of Interconnection. 

C. Self-Study of Interconnection Feasibility

55. In the Final Rule, the Commission adopted special interconnection procedures that 

allow the wind plant Interconnection Customer, when completing the Interconnection 

Request form required by section 3.3 of the LGIP, to provide the Transmission Provider 

with a simplified set of preliminary data depicting the wind plant as a single equivalent 

generator.31 Once the wind generator has provided this data and satisfied all other 

applicable Interconnection Request conditions, the special procedures permit the wind 

plant to enter the queue and receive the base case data as provided for in the LGIP. 

Finally, the special procedures adopted in the Final Rule require the wind plant 

Interconnection Customer to submit, within six months of submitting the Interconnection 

Request, completed detailed electrical design specifications and other data (including 

 31 “Single equivalent generator” information is design data that represents the 

aggregate electrical characteristics of the individual wind generators as a single generator. 
Docket No. RM05-4-001 -33- 

collector system layout data) needed by the Transmission Provider to complete the 

System Impact Study. 

56. Southern Company argues on rehearing that these provisions give wind developers 

a special preference that unfairly disfavors other generating technologies. 

57. EEI, NU and Southern Company contend that the “self-study” provisions of the 

Final Rule will add further complexity and uncertainty to the queue process and make 

queue management and assignment of cost responsibilities more difficult for 

Transmission Providers with large wind-powered generation projects in their queue. 

Southern Company adds that the self-study provisions could increase costs to market 

participants because the Transmission Provider will have to run multiple studies. EEI 

argues that until the industry can fully address the issues raised by these provisions in a 

technical forum, the Commission should remove the provisions from Appendix G. EEI 

and NU assert that the provisions do not protect against a wind plant Interconnection 

Customer making significant revisions to its project proposal. If the Commission does 

not remove the provisions entirely, EEI and NU suggest that the Commission allow the 

Transmission Provider to determine whether the detailed electrical design specifications 

later submitted by the wind plant Interconnection Customer are a material modification to 

the initial proposal, which would result in the initial Interconnection Application being 

withdrawn. 

58. Midwest ISO agrees with the Commission that a wind plant should be able to enter 
Docket No. RM05-4-001 -34- 

the queue and receive base case data based on preliminary design specifications. 

However, it seeks rehearing of the provision that permits a wind plant to wait up to six 

months before submitting final design specifications. It argues that this procedure 

promotes inefficiency because the Transmission Provider may be able to evaluate the 

proposed interconnection, but cannot do so because it lacks necessary data. Midwest ISO 

requests that the Commission revise the Appendix G self-study provisions to permit the 

Transmission Provider to notify the wind plant Interconnection Customer of its intent to 

start the System Impact Study. Once this notice is given, the wind plant developer would 

have five business days to “submit either actual design specifications or generic 

specifications based on typical equipment used in the industry.”32 Further, Midwest ISO 

proposes that if the wind plant Interconnection Customer submits generic specifications, 

it should have to accept cost uncertainty, because additional facilities may be required 

when the actual design specifications are taken into account. Midwest ISO asserts that 

this would limit delays in the study process and would allow the Transmission Provider 

to identify potential problems or eliminate tenuous or technically deficient projects earlier 

and to better use its resources to study proposed interconnections. 

Commission Conclusion

59. The Commission will deny these requests for rehearing. We will make one minor 

revision to label these special interconnection procedures for wind plants as “Appendix 

 32 Request for Rehearing of Midwest ISO at 4. 
Docket No. RM05-4-001 -35- 

 

7” to the LGIP, as discussed in more detail below. 

60. In response to arguments that the self-study procedures for wind plants give these 

plants a preference, we reiterate that these procedures were developed to recognize the 

technical differences of wind plants. Unlike conventional generators, wind plant design 

specifications and configurations can change significantly based on their placement on 

the transmission system.33 For example, the placement of wind turbines, voltage support 

devices, transformers, and other equipment (including the layout of the medium voltage 

collector system) depend on the location of the wind plant, the location of other 

generators on the transmission system, and other information included in the base case 

data.34 To accommodate these differences, the Final Rule permits wind plants to enter 

the interconnection queue with a set of preliminary electrical design specifications 

depicting the wind plant as a single generator, instead of providing detailed design 

specifications as required by Order No. 2003. Treating wind plants differently in this 

regard is not unduly discriminatory or preferential, but as noted elsewhere, simply 

recognizes that wind plants have different technical characteristics than the more 

traditional forms of generation that the LGIP and LGIA were designed to accommodate. 

We continue to believe that without this reasonable accommodation, Transmission 

Providers could frustrate the interconnection of wind plants by requiring them to submit 

33 Final Rule at P 97. 

34 Id.
Docket No. RM05-4-001 -36- 

detailed design data, which they cannot do until later in the interconnection process. 

61. We are not persuaded that the reasonable self-study provision we adopted will 

make the interconnection queue process significantly more difficult or complex. Wind 

plant Interconnection Customers who provide the preliminary single generator equivalent 

data are required to provide final detailed electrical design specifications no later than six 

months after submitting the initial Interconnection Request. This six-month time period 

takes into account the procedures needed before the start of the System Impact Study, 

including the Feasibility Study and negotiation of study agreements. Therefore, the 

Transmission Provider will receive from the wind plant the detailed design information 

needed to conduct the System Impact Study. For this reason, we also deny Midwest 

ISO’s request to modify the six-month deadline. If we adopted Midwest ISO’s proposed 

modifications, the Transmission Provider could request that the wind plant provide 

detailed design specifications at any time it believes it is ready to begin the System 

Impact Study, even a day after the initial Interconnection Request is submitted. As a 

result, this modification would defeat the purpose of permitting wind plants to submit 

preliminary design specifications, and could allow Transmission Providers to frustrate the 

interconnection of wind plants. 

62. With respect to the alternative suggestion by EEI and NU that the Transmission 

Provider be permitted to determine that a detailed design specification later submitted by 

the wind plant Interconnection Customer is a material modification of the Interconnection 

Request, we note that section 4.4 of the LGIP already addresses modifications and will 
Docket No. RM05-4-001 -37- 

apply to wind plants as well as other generating technologies. When applying this 

section to wind plant Interconnection Requests that first submit preliminary design 

specifications, Transmission Providers are not to consider the detailed design data 

provided later by the wind plant Interconnection Customer to be a material modification 

unless it significantly departs from the preliminary specifications provided. In other 

words, the detailed design provided later should be substantially the same as the initial 

single-generator equivalent design in terms of its costs and effect on the transmission 

system. 

63. Finally, to avoid confusion, the Commission will rename the Appendix G to the 

LGIP it adopted in the Final Rule as “Appendix 7, Interconnection Procedures for a Wind 

Generating Plant.” Accordingly, when complying with the Final Rule and this order on 

rehearing, public utilities must adopt the special interconnection procedures applicable to 

wind plants as Appendix 7 to their LGIPs. The low voltage ride-through, power factor 

design criteria and SCADA provisions should continue to be labeled “Appendix G” to the 

LGIA. 

D. Adoption of Appendix G on an Interim Basis Only

64. EEI and NU each generally argue that the Commission should apply Appendix G 

only on an interim basis, and should defer to NERC and Institute of Electrical and 

Electronics Engineers (IEEE) processes to develop formal technical standards. Southern 

Company argues that the Commission should defer to NERC, regional reliability 

councils, and other technical organizations to develop technical requirements for wind 
Docket No. RM05-4-001 -38- 

plants, and should suspend application of the Final Rule and formally request that these 

entities develop technical standards. Southern Company argues that this would avoid the 

problems that result from having the Commission review each variation to Appendix G 

as the technical standards are developed and revised. It also asserts that the Commission 

should not be the arbiter of technical disputes, such as the outcome of the System Impact 

Study or specific SCADA requirements, as the Final Rule provides. 

65. As noted above, NERC similarly argues that the Commission should only require 

wind plants to meet NERC and regional reliability council requirements, noting that 

Figure 1 is likely to remain static over time, which could hamper the development of 

wind generator technology. EEI notes that NERC has established a Wind Generator Task 

Force that is examining existing standards and will make proposals later this year. It 

states that the industry worldwide is addressing technical challenges presented by wind 

generation. Significant modifications are being developed for the German grid code, and 

Hydro-Québec is considering several reliability issues regarding wind generator 

interconnection. NERC further notes that Hydro-Québec requires the same dynamic 

performance of wind plants that it requires of other generating facilities, and that major 

wind turbine manufacturers have shown that they can meet this requirement. EEI 

proposes that the industry conduct a technical forum to resolve issues related to wind 

plant interconnection, concluding with formal recommendations to the Commission that 

could be used in a new NOPR, or to develop formal proposals for NERC or IEEE 

standards. 
Docket No. RM05-4-001 -39- 

Commission Conclusion

66. The Commission denies these requests for rehearing, and others noted earlier, that 

ask us to adopt Appendix G only on an interim basis. Standards are needed today 

because no nationwide standard is currently in place and it is uncertain when such a 

standard will be finalized. Without a firm standard in place, the current ad hoc practices 

for wind interconnection requirements may frustrate the interconnection of wind plants. 

As we noted in the Final Rule, Appendix G is necessary to recognize the technical 

differences between wind plants and traditional plants to ensure that the entry of wind 

generation into markets is not unnecessarily inhibited. 

67. We recognize, however, that the industry continues to study and address issues 

raised by the interconnection and operation of wind plants. For that reason, the 

Commission stated in the Final Rule that if another entity develops an alternate standard, 

a Transmission Provider may seek to justify adopting it as a variation from Appendix 

G.35 We also stated that we would consider a future industry petition to revise Appendix 

G to conform to a NERC-developed standard.36 We reiterate both of those statements 

 35 Id. at P 34. We note that in this order on rehearing, variations to the low voltage 

ride-through standard will only be permitted on an interconnection-wide basis. As we 

note above, however, non-conforming agreements may be submitted to the Commission. 

See P 33-34, supra.

36 Id.
Docket No. RM05-4-001 -40- 

here, and also note that under the Energy Policy Act of 2005, the Commission will be 

addressing mandatory reliability standards.37 

E. Transition Period

68. In the Final Rule, the Commission adopted a transition period that applies to the 

low voltage ride-through, power factor design criteria and SCADA requirements. These 

technical requirements in the Final Rule Appendix G, if applicable, apply only to LGIAs 

signed, filed with the Commission in unexecuted form, or filed as non-conforming 

agreements, on or after January 1, 2006, or the date six months after publication of the 

Final Rule in the Federal Register, whichever is later.38 The Commission adopted this 

transition period to allow wind equipment currently in the process of being manufactured 

to be completed without delay or added expense, and to ensure that the Final Rule did not 

interrupt the supply of wind turbines. 

69. NRECA/APPA argues that the transition period is arbitrary, capricious, and 

unduly discriminatory. NRECA/APPA asserts that the Commission adopted the 

 37 See Energy Policy Act of 2005, Pub. L. No. 109-58, § 1211, 119 Stat. 594, 941 

(2005). 

38 The Final Rule was published in the Federal Register on June 16, 2005. Thus, 

the low voltage ride-through, power factor design criteria and reactive power provisions 

in the Final Rule, as revised herein, will apply to LGIAs signed, filed with the 

Commission in unexecuted form, or filed as non-conforming agreements, on or after 

January 1, 2006. 
Docket No. RM05-4-001 -41- 

transition period with no technical justification and no explanation of how the transition 

period will maintain the reliability of the transmission system. They contend that the 

transition period requires transmission customers and competing generators to bear the 

reliability effects of wind plants interconnected during the transition period. While 

NRECA/APPA state that there are “valid commercial considerations” that should be 

taken into account for the existing inventory of wind equipment, they contend that such 

determinations should be made on a case-by-case basis. 

Commission Conclusion

70. The Commission declines to remove the transition period as NRECA/APPA 

request. We adopted this reasonable transition mechanism to allow wind turbines in the 

process of being manufactured to be completed without delay or additional expense.39 

The transition period ensures that the supply of wind turbines is not unfairly or 

unreasonably interrupted.40 Furthermore, contrary to NRECA/APPA’s contention, the 

Commission considered the possible reliability effects of the transition period, and 

concluded that the remaining provisions of Order No. 2003 will adequately protect 

reliability.41 The remaining provisions of Order No. 2003 will also ensure that other 

generators or the Transmission Provider will not bear the reliability effects of a wind 

 39 Final Rule at P 115. 

40 Id.

41 Id.
Docket No. RM05-4-001 -42- 

plant because that rule, and the LGIA and LGIP contained in it, ensure that generating 

facilities are not interconnected in a manner that degrades reliability. 

III. Document Availability

71. In addition to publishing the full text of this document in the Federal Register, the 

Commission provides all interested persons an opportunity to view and/or print the 

contents of this document via the Internet through FERC's Home Page 

(http://www.ferc.gov) and in FERC's Public Reference Room during normal business 

hours (8:30 a.m. to 5:00 p.m. Eastern time) at 888 First Street, N.E., Room 2A, 

Washington, D.C. 20426. 

72. From the Commission’s Home Page on the Internet, this information is available 

in the Commission’s document management system, eLibrary. The full text of this 

document is available on eLibrary in PDF and Microsoft Word format for viewing, 

printing, and/or downloading. To access this document in eLibrary, type the docket 

number excluding the last three digits of this document in the docket number field. 

73. User assistance is available for eLibrary and the Commission’s website during 

normal business hours. For assistance, please contact FERC Online Support at 1-866-

208-3676 (toll free) or 202-502-6652 (e-mail at FERCOnlineSupport@FERC.gov), or the 

Public Reference Room at 202-502-8371, TTY 202-502-8659 (e-mail at 

public.referenceroom@ferc.gov). 

IV. Effective Date

74. As noted above, on August 5, 2005, the Commission issued an order extending the 
Docket No. RM05-4-001 -43- 

effective date of the Final Rule to October 14, 2005.42 Those provisions of the Final 

Rule not revised in this order on rehearing and clarification are effective as of that date. 

Changes made to the Final Rule in this order on rehearing and compliance will become 

effective on [INSERT DATE 30 DAYS AFTER DATE OF PUBLICATION IN THE 

FEDERAL REGISTER]. 

V. Compliance with the Final Rule and Order on Rehearing and Clarification

75. In the Commission’s August 5, 2005 order extending the effective date of the 

Final Rule, the Commission also extended to November 14, 2005, the date by which all 

public utilities that own, control, or operate transmission facilities in interstate commerce 

are to adopt, in their OATTS, the Final Rule Appendix 7 (as described above)43 as an 

amendment to the LGIP, and Final Rule Appendix G as an amendment to the LGIA. By 

further notice issued October 28, 2005, the Commission extended this date further, to 

December 30, 2005. Public utilities who have already filed a Final Rule Appendix G as 

amendments to the LGIPs and LGIAs in their OATTs must file, by December 30, 2005, 

the revisions to the Final Rule Appendix G to the LGIA made in this order on rehearing. 

 42 Order Granting Extension of Effective Date and Extending Compliance Date, 70 

FR 47093 (Aug. 12, 2005), 112 FERC ¶ 61,173 (2005). 

43 See supra, P 60. 
Docket No. RM05-4-001 -44- 

List of Subjects in 18 C.F.R. Part 35

Electric power rates; Electric utilities. 

By the Commission. Chairman Kelliher dissenting in part with a separate statement 

 attached. 

( S E A L ) 

Magalie R. Salas, 

Secretary. 
Docket No. RM05-4-001 -45- 

In consideration of the foregoing, the Commission revises part 35, Chapter I, Title 

18 of the Code of Federal Regulations as follows. 

PART 35 Β FILING OF RATE SCHEDULES

1. The authority citation for part 35 continues to read as follows: 

Authority: 16 U.S.C. §§ 791a-825r, §§ 2601-2645; 31 U.S.C. § 9701; 42 U.S.C. 

§§ 7101-7352. 

2. In § 35.28, the first sentences of currently existing paragraphs (f)(1) and 

(f)(1)(iii) are revised, a new paragraph (f)(1)(iii) is added, and currently existing 

paragraph (f)(1)(iii) is renumbered to account for new paragraph (f)(1)(iii), all to read as 

follows: 

§ 35.28 Non-discriminatory open access transmission tariff. 

* * * * * 

(f) Standard generator interconnection procedures and agreements. 

(1) Every public utility that is required to have on file a non-discriminatory open 

access transmission tariff under this section must amend such tariff by adding the 

standard interconnection procedures and agreement contained in Order No. 2003, FERC 

Stats. & Regs. & 31,146 (Final Rule on Generator Interconnection), as amended by the 

Commission in Order No. 661, FERC Stats. & Regs. ¶ 31,186 (Final Rule on 

Interconnection for Wind Energy), and the standard small generator interconnection 
Docket No. RM05-4-001 -46- 

procedures and agreement contained in Order No. 2006, FERC Stats. & Regs. ¶ 31,180 

(Final Rule on Small Generator Interconnection), or such other interconnection 

procedures and agreements as may be approved by the Commission consistent with Order 

No. 2003, FERC Stats. & Regs. & 31,146 (Final Rule on Generator Interconnection) and 

Order No. 2006, FERC Stats. & Regs. ¶ 31,180 (Final Rule on Small Generator 

Interconnection). 

(i) The amendment to implement the Final Rule on Generator Interconnection 

required by the preceding subsection must be filed no later than January 20, 2004. 

(ii) The amendment to implement the Final Rule on Small Generator 

Interconnection required by the preceding subsection must be filed no later than August 

12, 2005. 

(iii) The amendment to implement the Final Rule on Interconnection for Wind 

Energy required by the preceding subsection must be filed no later than December 30, 

2005. 

(iv) Any public utility that seeks a deviation from the standard interconnection 

procedures and agreement contained in Order No. 2003, FERC Stats. & Regs. & 31,146 

(Final Rule on Generator Interconnection), as amended by the Commission in Order No. 

661, FERC Stats. & Regs. ¶ 31,186 (Final Rule on Interconnection for Wind Energy), or 

the standard small generator interconnection procedures and agreement contained in 
Docket No. RM05-4-001 -47- 

Order No. 2006, FERC Stats. & Regs. ¶ 31,180 (Final Rule on Small Generator 

Interconnection), must demonstrate that the deviation is consistent with the principles of 

either Order No. 2003, FERC Stats. & Regs. & 31,146 (Final Rule on Generator 

Interconnection) or Order No. 2006, FERC Stats. & Regs. ¶ 31,180 (Final Rule on Small 

Generator Interconnection). 

[NOTE: THE APPENDICES WILL NOT BE PUBLISHED IN THE CODE 

OF FEDERAL REGULATIONS] 
Docket No. RM05-4-001 -48- 

 Appendix A

List of Entities Requesting Rehearing and/or Clarification or Submitting Comments 

and Acronyms

ATC – American Transmission Company LLC 

CenterPoint – CenterPoint Energy Houston Electric, LLC 

EEI – Edison Electric Institute 

FPL Energy – FPL Energy, LLC 

ISO-NE – ISO New England, Inc. 

Midwest ISO – Midwest Independent Transmission System Operator, Inc. 

National Grid – National Grid USA 

NERC – North American Electric Reliability Council 

New York ISO – New York Independent System Operator, Inc. 

NRECA/APPA – National Rural Electric Cooperative Association and American Public 

Power Association 

NU – Northeast Utilities 

PJM – PJM Interconnection, L.L.C. 

SCE - Southern California Edison Company

Southern Company – Southern Company Services, Inc 
Docket No. RM05-4-001 -49- 

 Appendix B 

[NOTE: THESE PROVISIONS TO BE ADOPTED AS APPENDIX G TO THE 

LGIA] 

APPENDIX G 

INTERCONNECTION REQUIREMENTS FOR A WIND GENERATING PLANT 

 Appendix G sets forth requirements and provisions specific to a wind generating 

plant. All other requirements of this LGIA continue to apply to wind generating plant 

interconnections. 

A. Technical Standards Applicable to a Wind Generating Plant 

i. Low Voltage Ride-Through (LVRT) Capability

 A wind generating plant shall be able to remain online during voltage disturbances 

up to the time periods and associated voltage levels set forth in the standard below. The 

LVRT standard provides for a transition period standard and a post-transition period 

standard. 

Transition Period LVRT Standard

 The transition period standard applies to wind generating plants subject to FERC 

Order 661 that have either: (i) interconnection agreements signed and filed with the 

Commission, filed with the Commission in unexecuted form, or filed with the 

Commission as non-conforming agreements between January 1, 2006 and December 31, 

2006, with a scheduled in-service date no later than December 31, 2007, or (ii) wind 
Docket No. RM05-4-001 -50- 

generating turbines subject to a wind turbine procurement contract executed prior to 

December 31, 2005, for delivery through 2007. 

1. Wind generating plants are required to remain in-service during three-phase faults 

with normal clearing (which is a time period of approximately 4 – 9 cycles) and 

single line to ground faults with delayed clearing, and subsequent post-fault voltage 

recovery to prefault voltage unless clearing the fault effectively disconnects the 

generator from the system. The clearing time requirement for a three-phase fault 

will be specific to the wind generating plant substation location, as determined by 

and documented by the transmission provider. The maximum clearing time the 

wind generating plant shall be required to withstand for a three-phase fault shall be 

9 cycles at a voltage as low as 0.15 p.u., as measured at the high side of the wind 

generating plant step-up transformer (i.e. the transformer that steps the voltage up 

to the transmission interconnection voltage or “GSU”), after which, if the fault 

remains following the location-specific normal clearing time for three-phase faults, 

the wind generating plant may disconnect from the transmission system. 

2. This requirement does not apply to faults that would occur between the wind 

generator terminals and the high side of the GSU or to faults that would result in a 

voltage lower than 0.15 per unit on the high side of the GSU serving the facility. 

3. Wind generating plants may be tripped after the fault period if this action is 

intended as part of a special protection system. 
Docket No. RM05-4-001 -51- 

4. Wind generating plants may meet the LVRT requirements of this standard by the 

performance of the generators or by installing additional equipment (e.g., Static 

VAr Compensator, etc.) within the wind generating plant or by a combination of 

generator performance and additional equipment. 

5. Existing individual generator units that are, or have been, interconnected to the 

network at the same location at the effective date of the Appendix G LVRT 

Standard are exempt from meeting the Appendix G LVRT Standard for the 

remaining life of the existing generation equipment. Existing individual generator 

units that are replaced are required to meet the Appendix G LVRT Standard. 

Post-transition Period LVRT Standard

All wind generating plants subject to FERC Order No. 661 and not covered by the 

transition period described above must meet the following requirements: 

1. Wind generating plants are required to remain in-service during three-phase faults 

with normal clearing (which is a time period of approximately 4 – 9 cycles) and 

single line to ground faults with delayed clearing, and subsequent post-fault 

voltage recovery to prefault voltage unless clearing the fault effectively 

disconnects the generator from the system. The clearing time requirement for a 

three-phase fault will be specific to the wind generating plant substation location, 

as determined by and documented by the transmission provider. The maximum 

clearing time the wind generating plant shall be required to withstand for a threephase fault shall be 9 cycles after which, if the fault remains following the 
Docket No. RM05-4-001 -52- 

location-specific normal clearing time for three-phase faults, the wind generating 

plant may disconnect from the transmission system. A wind generating plant shall 

remain interconnected during such a fault on the transmission system for a voltage 

level as low as zero volts, as measured at the high voltage side of the wind GSU. 

2. This requirement does not apply to faults that would occur between the wind 

generator terminals and the high side of the GSU. 

3. Wind generating plants may be tripped after the fault period if this action is 

intended as part of a special protection system. 

4. Wind generating plants may meet the LVRT requirements of this standard by the 

performance of the generators or by installing additional equipment (e.g., Static 

VAr Compensator) within the wind generating plant or by a combination of 

generator performance and additional equipment. 

5. Existing individual generator units that are, or have been, interconnected to the 

network at the same location at the effective date of the Appendix G LVRT 

Standard are exempt from meeting the Appendix G LVRT Standard for the 

remaining life of the existing generation equipment. Existing individual generator 

units that are replaced are required to meet the Appendix G LVRT Standard.

 ii. Power Factor Design Criteria (Reactive Power)

A wind generating plant shall maintain a power factor within the range of 0.95 

leading to 0.95 lagging, measured at the Point of Interconnection as defined in this LGIA, 

if the Transmission Provider’s System Impact Study shows that such a requirement is 
Docket No. RM05-4-001 -53- 

necessary to ensure safety or reliability. The power factor range standard can be met by 

using, for example, power electronics designed to supply this level of reactive capability 

606 (taking into account any limitations due to voltage level, real power output, etc.) or 

fixed and switched capacitors if agreed to by the Transmission Provider, or a combination 

of the two. The Interconnection Customer shall not disable power factor equipment 

while the wind plant is in operation. Wind plants shall also be able to provide sufficient 

dynamic voltage support in lieu of the power system stabilizer and automatic voltage 

regulation at the generator excitation system if the System Impact Study shows this to be 

required for system safety or reliability. 

iii. Supervisory Control and Data Acquisition (SCADA) Capability 

The wind plant shall provide SCADA capability to transmit data and receive 

instructions from the Transmission Provider to protect system reliability. The 

Transmission Provider and the wind plant Interconnection Customer shall determine what 

SCADA information is essential for the proposed wind plant, taking into account the size 

of the plant and its characteristics, location, and importance in maintaining generation 

resource adequacy and transmission system reliability in its area. 
Docket No. RM05-4-001 -54- 

 Appendix C 

[NOTE: THESE PROVISIONS TO BE ADOPTED AS APPENDIX G TO THE 

LGIP]

APPENDIX 7 

INTERCONNECTION PROCEDURES FOR A WIND GENERATING PLANT 

Appendix G sets forth procedures specific to a wind generating plant. All other 

requirements of this LGIP continue to apply to wind generating plant interconnections. 

A. Special Procedures Applicable to Wind Generators

 The wind plant Interconnection Customer, in completing the Interconnection 

Request required by section 3.3 of this LGIP, may provide to the Transmission Provider a 

set of preliminary electrical design specifications depicting the wind plant as a single 

equivalent generator. Upon satisfying these and other applicable Interconnection Request 

conditions, the wind plant may enter the queue and receive the base case data as provided 

for in this LGIP. 

 No later than six months after submitting an Interconnection Request completed in 

this manner, the wind plant Interconnection Customer must submit completed detailed 

electrical design specifications and other data (including collector system layout data) 

needed to allow the Transmission Provider to complete the System Impact Study.
 

UNITED STATES OF AMERICA 

FEDERAL ENERGY REGULATORY COMMISSION 

Interconnection for Wind Energy Docket No. RM05-4-001 

(Issued December 12, 2005) 

Joseph T. KELLIHER, Chairman, dissenting in part: 

I vote for this order because it constitutes an improvement over the final rule. I 

agree with the Commission’s decision to grant rehearing with respect to the low voltage 

ride-through (LVRT) provisions and to adopt the joint recommendation of NERC and 

AWEA. As the order points out, by adopting a definitive, uniform, LVRT standard, the 

Commission “provide[s] certainty” to the industry and “ensure[s] that reliability is 

maintained and NERC planning standards are met.”1

Unfortunately, the Commission’s decision on LVRT contrasts with its decision to 

exempt wind generators from compliance with the same power factor standard as all other 

generators. The Commission requires all non-wind generators to maintain a power factor 

within the range of 0.95 leading to 0.95 lagging, which NERC has determined to be 

“within a range required by Good Utility Practice.”2

 Order No. 661, however, singles out 

wind generators for special treatment by exempting them from meeting the standard power 

factor requirement unless the Transmission Provider demonstrates in the System Impact 

Study that reactive power capability is necessary to ensure the safety or reliability of the 

transmission system. In my view, exempting only wind generators from the power factor 

standard does not provide certainty to the industry, results in an undue preference for wind 

generators and does not adequately ensure that reliability of the transmission system is 

maintained. 

Section 205 of the Federal Power Act broadly precludes public utilities, in any 

transmission or sale subject to the Commission’s jurisdiction, from “mak[ing] or grant[ing] 

any undue preference or advantage to any person or subject[ing] any person to any undue 

prejudice or disadvantage. . . .”3

 In my view, Order No. 661 gives preferential treatment to 

1

 Order at P34. 

2

 Order No. 2003 at P541. 

3

 16 U.S.C. § 824d(b). 
Docket No. RM05-4-001 -2- 

 

wind generators, since it exempts wind generators from meeting the same power factor 

requirement as all other non-wind generators. The issue is whether the preferential 

treatment afforded to wind generators is undue. 

I do not believe that either the record or the explanation offered in this order 

provides a basis for giving preferential treatment to wind generators when it comes to 

meeting the power factor requirement. The order’s attempt to justify discriminating in 

favor of wind generators as an accommodation for “technical differences”4

 is not 

convincing. The only “technical” difference identified is the assertion that compliance 

with reactive power capability is more expensive for wind generators than for other 

generator resources.5

 While one can understand why wind generators would like to be 

relieved of the added cost of complying with the same power factor standard as all other 

non-wind generators, I fail to see how the desire to avoid incurring the costs of complying 

with the Commission’s standardized power factor requirement constitutes a technological 

difference warranting discriminatory treatment. 

Equally troubling, I disagree with the Commission’s decision to brush aside the 

concerns raised by NERC and other protesters that the Commission has “lowered the bar” 

for reliability by shifting the burden to the Transmission Provider to justify the need for 

wind generators to comply with the same power factor requirement as non-wind 

generators. I find little comfort in the Commission’s view that any reliability concerns can 

be addressed in the System Impact Study if the Transmission Provider proves that a wind 

generator’s compliance with the reactive power factor standard is necessary. In my view, 

shifting the burden to Transmission Providers to make such a showing simply cannot be 

reconciled with the approach taken by the Commission in Order No. 2003 which presumes 

the need for all generators to comply with power factor requirement under “Good Utility 

Practice.” 6

As a result, I would have granted rehearing and returned to the approach proposed 

by the Commission in the NOPR of requiring all generators to meet the same power factor 

4

 Order at P45. 

5 Id. (“One of these [technical] differences is that for wind plants, reactive power 

capability is a significant added cost, while it is not a significant additional cost for 

traditional generators.”). 

6

 Order No. 2003 at PP541-42. 
Docket No. RM05-4-001 -3- 

standard absent a waiver by the Transmission Provider. Accordingly, I dissent in part from 

the order. 

_____________________ 

Joseph T. Kelliher