Grid congestion & captive power

When a transmission line binds, generation on the trapped side gets curtailed — that underutilized “captive” power is exactly what a co-located datacenter can absorb, often with a faster interconnection than a greenfield build (the constraint relief a new load provides is already valued). All six ISO markets: the 248 most-constrained points in ERCOT from 18,382 priced SCED intervals; the 290 binding facilities in PJM from 28,023 five-minute intervals; the 610 binding constraints in MISO from 29,181 intervals; the 517 binding constraints in SPP from 29,221 intervals; the 223 binding branches and nomograms in CAISO from 30,750 intervals; and the 57 limiting facilities in NYISO from 14,643 binding real-time intervals (2026-06-01 → 2026-09-16). Each ranked by how often it binds and how expensive relief gets.

How to read this: the trendcolumn compares this month's severity per binding interval with last month's (▲ binding more, ▼ less, ● new this month); the captive-power index strip above each table is the market's total severity by month. A high binding count means the pinch point recurs; a high shadow price($/MW to relieve) means it's expensive, i.e. severely constrained. Most sit on 138 kV lines in South & West Texas (the Rio Grande / Laredo corridor) — the parts of ERCOT where trapped generation is most concentrated today.

ERCOT — Texas

Most sit on 138 kV lines in South & West Texas (the Rio Grande / Laredo corridor) — the parts of ERCOT where trapped generation is most concentrated today.

Captive-power index2026-02 → 2026-10-23% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	1545__A	FLTSW → PRSSW138 kV	▼	3,010	$3,500	$50
2	2270__B	MEXTP → ITALY69 kV	▼	5,648	$1,802	$342
3	BRUNI_69_1	BRUNI138 kV	▼	2,179	$3,500	$674
4	1715__B	TMPSW → FRYSW138 kV	▼	1,894	$3,500	$461
5	SEA_AAT1	SEA138 kV	▼	1,847	$3,500	$1,556
6	6830__B	CRDSW → OLNEY69 kV	▼	2,222	$2,800	$240
7	WESLCO_HIDLBRG_1	MV_HBRG4 → MV_WESL4138 kV	▼	4,300	$1,211	$210
8	D5_S1_1	HOWARD → LEON_CRK138 kV	▼	1,171	$3,500	$69
9	MAGRUD_VICTOR2_1	VICTORIA → MAGRUDER138 kV	▼	1,053	$3,500	$466
10	6200__F	TYPRK → PLYAM138 kV	▼	995	$3,500	$478
11	BALLINGE_FMRL	BALLINGE1 kV	▼	1,228	$2,800	$965
12	BENTS_FRTER_1B_1	FRONTERA → S_MISSIN138 kV	▼	1,540	$1,976	$26
13	LPLMK_LPLNE_1	LPLMK → LPLNE115 kV	▼	816	$3,313	$356
14	MIL_LIPAN_1	LONG → LIPAN138 kV	▬	684	$3,500	$208
15	1710__A	SALDS → SONTERRA138 kV	▼	1,101	$2,106	$394
16	NLARSW_PILONC1_1	PILONCIL → NLARSW138 kV	▼	1,545	$1,461	$275
17	STPWAP39_1	STP → WAP345 kV	▼	4,834	$443	$110
18	138_ALV_NAL_1	TNNALVIN → ALVIN138 kV	▬	589	$3,500	$26
19	SOLSTICE_PST1	SOLSTICE138 kV	▬	1,306	$1,264	$119
20	651__B	CMNSW → CMNTP138 kV	▬	1,309	$1,204	$109
21	NUECES_WHITE_2_1	NUECES_B → WHITE_PT138 kV	▬	523	$2,865	$109
22	ASHERT_CATARI1_1	ASHERTON → CATARINA138 kV	▲	538	$2,759	$142
23	35100__A	PKRSW → HCKSW345 kV	▼	311	$4,500	$1,663
24	FORSW_MR3H	FORSW345 kV	▼	306	$4,500	$1,866
25	NELRIO	—	●	5,001	$258	$17
26	SND_ORAN_1	ORNGROV → SNDIEGS69 kV	▼	454	$2,800	$746
27	PALOUS_WOLFCA1_1	PALOUSE → WOLFCAMP138 kV	▼	2,080	$610	$191
28	PAWNEE_SPRUCE_1	PAWNEE → CALAVERS345 kV	▼	1,117	$1,110	$87
29	GREENL_WEAVER1_1	WEAVERRD → GREENLK69 kV	▼	442	$2,800	$1,063
30	TREADW_YELWJC1_1	TREADWEL → YELWJCKT138 kV	●	1,630	$758	$116
31	6405__C	HLSES → RMTPW138 kV	▬	331	$3,500	$277
32	35055__A	SAMSW → VENSW345 kV	▬	2,038	$547	$128
33	DILLEYSW_XF1H	DILLEYSW138 kV	▬	343	$3,028	$704
34	CARIZOSPG_BEVO_1	BEVO → CARIZOS69 kV	▼	344	$2,800	$483
35	3170__B	SMPST → BNTDR138 kV	▼	255	$3,500	$2,971
36	610__B	TMPSW → TMPSE138 kV	▬	249	$3,500	$1,852
37	378T387_1	HWRDTP → WELLBR138 kV	▬	244	$3,500	$1,779
38	6437__F	SCRCV → KNAPP138 kV	▲	818	$1,019	$209
39	3610__G	PGTP1 → PDSES138 kV	▼	221	$3,500	$1,980
40	6945__A	MGSES → CATSW345 kV	●	1,484	$486	$89
41	6293__C	MARSW → DEVIT138 kV	▬	196	$3,500	$1,674
42	ABINDU_MULBER1_1	MULBERRY → ABINDUST138 kV	▼	186	$3,500	$1,636
43	1160__A	HKBRY → VLYRN138 kV	▬	180	$3,500	$2,062
44	6217__A	WLVSW → GAILS138 kV	▬	176	$3,500	$264
45	FORTMA_YELWJC1_1	YELWJCKT → FORTMA138 kV	●	325	$1,891	$137
46	6840__B	NVKSW → ANARN69 kV	▼	701	$867	$128
47	OB_WAP98_A	WAP → OB345 kV	▼	536	$1,131	$142
48	DT_PK_91_A	DT → PK138 kV	▲	165	$3,500	$510
49	POT_OAKS_1	POTEETS → OAKS969 kV	▼	344	$1,658	$402
50	GABRIE_AT1	GABRIE69 kV	●	192	$2,836	$707
51	HAINE__LA_PAL1_1	LA_PALMA → HAINE_DR138 kV	▼	633	$842	$61
52	940__A	ENWSW → TMPTN138 kV	▬	909	$574	$38
53	630__A	BLTON → BLTSW138 kV	▬	145	$3,500	$862
54	COLLE_JUPIT_1	COLLEGE → JUPITER138 kV	●	144	$3,500	$799
55	POT_PEAR_1	PEARSALL → POTEETS69 kV	▬	455	$1,100	$290
56	BI_SMR98_A	SMITHERS → BI345 kV	●	109	$4,500	$197
57	1395__A	MESQE → OATES138 kV	▼	136	$3,500	$2,301
58	HEXT_YELWJC1_1	YELWJCKT → HEXT69 kV	▬	217	$1,963	$76
59	E_PASP	—	▬	637	$646	$69
60	MDOPHR99_A	MDO → PHR345 kV	▼	1,050	$381	$53

PJM — Mid-Atlantic & Midwest

The slowest, most expensive interconnection market in the country is also where trapped generation is worth the most. The 230 kV Graceton–Manor and Conastone–Peach Bottom paths in the Maryland/Pennsylvania corridor, the Sunbury and Lenox constraints in central and northeast Pennsylvania, and the Chicago 138 kV cluster bind for thousands of intervals a season — a load on the generation side of any of them is relief PJM already prices.

Captive-power index2026-06 → 2026-09+43% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	GRACETON-MANOR GRA-MANO A 230 KV	GRACETON → MANOR230 kV	▲	9,218	$2,000	$333
2	LENOX-MACNEW_T LEN-MAC A 115 KV	LENOX → MACNEW_T115 kV	▼	5,903	$2,000	$430
3	Chicago - Praxair3 138 kV l/o Wilton Center - Dumont 765 kV	Chicago → Praxair3138 kV	▲	1,588	$4,000	$696
4	ELIMSPOR-SUNBURY A 230 KV	ELIMSPOR → SUNBURY230 kV	▼	3,086	$2,000	$16
5	CONASTON-OTTCRKPL 2302 B 230 KV	CONASTON → OTTCRKPL230 kV	▲	2,074	$2,000	$276
6	CONASTON-PEACHBOT 5012 B 500 KV	CONASTON → PEACHBOT500 kV	▬	1,759	$2,000	$283
7	KELFORD -EARLEYS 126A B 115 KV	KELFORD → EARLEYS115 kV	▲	1,658	$2,000	$71
8	ELIMSPOR-SUNBURY B 230 KV	ELIMSPOR → SUNBURY230 kV	▼	1,641	$2,000	$17
9	ETOWANDA-HILLSIDE 2002 TIE B 230 KV	ETOWANDA → HILLSIDE230 kV	▲	3,238	$1,000	$83
10	CRETSTJO-STJOHNS 94507 B 345 KV	CRETSTJO → STJOHNS345 kV	▼	1,543	$2,000	$217
11	MILLWDPL-SAKRON MIL-SAK B 230 KV	MILLWDPL → SAKRON230 kV	▬	1,413	$2,000	$303
12	HIGHLAOE-COMERC A 138 KV	HIGHLAOE → COMERC138 kV	▲	1,337	$2,000	$702
13	MORRISVL-LOUDOUN4 569A A 500 KV	MORRISVL → LOUDOUN4500 kV	▼	1,314	$2,000	$1,327
14	Kokomo - Tipton W. 230kV l/o Nucor - Cayuga 345kV	Kokomo → Tipton W.230 kV	▲	1,233	$2,000	$688
15	PIERCE-DEARBORN B 345 KV	PIERCE → DEARBORN345 kV	▲	2,395	$1,000	$187
16	BUFFINGT-CLIFTYCR BUF-CLI B 345 KV	BUFFINGT → CLIFTYCR345 kV	▼	1,135	$2,000	$346
17	Batesville-Hubble 138 l/o Tanners Crk-Miami Fort 345	Batesville-Hubble 138 l/o Tanners Crk-Miami Fort	▼	678	$3,000	$892
18	MARDELA-VIENNA 6708-1 B 69 KV	MARDELA → VIENNA69 kV	▼	968	$2,000	$921
19	NOTTINGHM 2-3 SER DEV A 230 KV	NOTTINGHM 2-3 SER DEV A230 kV	▲	926	$2,000	$332
20	EDWSF-DICERSO2311/203A TIE B 230 KV	EDWSF → DICERSO2311230 kV	▲	865	$2,000	$66
21	CHARLTSV-PROFITDP 2054B1 A 230 KV	CHARLTSV → PROFITDP230 kV	▼	833	$2,000	$828
22	94 HAURD-11323 11323 A 138 KV	94 HAURD-11323138 kV	▼	824	$2,000	$94
23	COOLSPRI-MILFORD 23069 A 230 KV	COOLSPRI → MILFORD230 kV	▼	823	$2,000	$1,046
24	QUAD CITY - SUB91 345 kV l/o CORDOVA - SUB39 345 kV	QUAD CITY → SUB91345 kV	▼	803	$2,000	$453
25	AQUAHAR-CRANESCR 2104T A 230 KV	AQUAHAR → CRANESCR230 kV	▬	667	$2,000	$986
26	12 DRESDEN 45TR81 CT H 345 KV	12 DRESDEN 45TR81 CT H345 kV	▲	615	$2,000	$1,029
27	COOPERPE-PEACHTAP COO-PEA A 230 KV	COOPERPE → PEACHTAP230 kV	▬	605	$2,000	$330
28	CARL PN-GARDNERS 976 B 115 KV	CARL PN-GARDNERS115 kV	▼	593	$2,000	$735
29	FREMNT-FREMONTC A 138 KV	FREMNT → FREMONTC138 kV	▲	563	$2,000	$1,138
30	MIAMIFOR 9 XFORMER H 345 KV	MIAMIFOR 9 XFORMER H345 kV	▲	560	$2,000	$1,288
31	CONCRDDP-LAURELDP 6722-1 B 69 KV	CONCRDDP → LAURELDP69 kV	▼	557	$2,000	$1,988
32	OX4 TX2 XFORMER H 500 KV	OX4 TX2 XFORMER H500 kV	▬	547	$2,000	$1,952
33	Sugar Creek (Mirant)-Dresser 345kV l/o Nucor Cayuga 345kV	Sugar Creek (Mirant)-Dresser345 kV	▬	516	$2,000	$328
34	PLEASNTV-ASHBURN 274D A 230 KV	PLEASNTV → ASHBURN230 kV	▼	510	$2,000	$1,109
35	WMOULTON-09ST_MRY B 69 KV	WMOULTON → 09ST_MRY69 kV	▲	496	$2,000	$1,253
36	116 GOOD-900 ELWO 11622 B 345 KV	116 GOOD-900 ELWO345 kV	▬	472	$2,000	$372
37	JACK ME-TMI 1051 B 230 KV	JACK ME-TMI230 kV	▼	472	$2,000	$674
38	HARWGATE-LOCKS 205C B 230 KV	HARWGATE → LOCKS230 kV	▲	447	$2,000	$512
39	GOOSECRE TX1 XFORMER H 500 KV	GOOSECRE TX1 XFORMER H500 kV	▬	387	$2,000	$1,190
40	ASPENSLR-ROXBURY ASP-ROXB A 115 KV	ASPENSLR → ROXBURY115 kV	▬	377	$2,000	$1,148
41	CLOVER-EASTERS 2226A A 230 KV	CLOVER → EASTERS230 kV	▼	363	$2,000	$777
42	COLLEGEC-COLLINSV TIE B 138 KV	COLLEGEC → COLLINSV138 kV	▼	341	$2,000	$1,270
43	EVERTSUB-STROY EVE-STR A 115 KV	EVERTSUB → STROY115 kV	▬	331	$2,000	$390
44	MapleSt-Chrysler 138kV l/o HighlandPark-NewLondon 230kV	MapleSt-Chrysler138 kV	▲	211	$3,000	$1,860
45	HYATTCS-MARYSVI2 MAR-HYA2 B 345 KV	HYATTCS → MARYSVI2345 kV	▬	314	$2,000	$811
46	STEELCTY 500/230 XF H 500 KV	STEELCTY 500/230 XF H500 kV	▬	309	$2,000	$1,172
47	TRANSFER INTERFACE: APSOUTH	TRANSFER INTERFACE: APSOUTH	▬	295	$2,000	$635
48	MALISZEW ORANGE SER DEV A 138 KV	MALISZEW ORANGE SER DEV A138 kV	▬	287	$2,000	$1,543
49	Douglas - Francisco 345 kV l/o Poseyville East - AB Brown 345 kV	Douglas → Francisco345 kV	▬	285	$2,000	$358
50	MTAIRYTP-RENAN 35E2 B 69 KV	MTAIRYTP → RENAN69 kV	▬	265	$2,000	$127
51	66 E FRN TR83CT-P XFORMER H 345 KV	66 E FRN TR83CT-P XFORMER H345 kV	▲	261	$2,000	$881
52	OTTCRKPL-YORKANA A 230 KV	OTTCRKPL → YORKANA230 kV	▼	261	$2,000	$219
53	ASHBURN-GOOSECRE 227D B 230 KV	ASHBURN → GOOSECRE230 kV	▬	260	$2,000	$1,781
54	NILES-EVERGFE B 138 KV	NILES → EVERGFE138 kV	●	249	$2,000	$500
55	EMILIE EMIL7TR XFORMER H 230 KV	EMILIE EMIL7TR XFORMER H230 kV	●	244	$2,000	$293
56	EVERTSUB-STROY EVE-STR B 115 KV	EVERTSUB → STROY115 kV	▬	236	$2,000	$182
57	TERMINAL 12 XFORMER H 345 KV	TERMINAL 12 XFORMER H345 kV	▬	229	$2,000	$1,634
58	NORTHWOO 6 BANK XFORMER H 230 KV	NORTHWOO 6 BANK XFORMER H230 kV	▼	227	$2,000	$1,595
59	POSSUMP4 TX1 XFORMER H 500 KV	POSSUMP4 TX1 XFORMER H500 kV	●	226	$2,000	$1,027
60	Monroe-Lallendorf 345 kV l/o Lulu 345 kV Sub	Monroe-Lallendorf345 kV	●	223	$2,000	$331

MISO — Central US & Gulf

Fifteen states from Minnesota to Louisiana. MISO's binding constraints cluster on the seams — the Toledo/Detroit 345 kV ties into PJM, the Missouri and Iowa 161 kV corridors, and the Gulf export paths — and on flowgates where wind in the north cannot reach load in the south. Named by flowgate; the monitored branch and contingency are in the data.

Captive-power index2026-06 → 2026-09+87% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	WEC34101_SUSSEX_36341_1	SUSSEX	▲	7,815	$3,000	$158
2	NIP13X01_BARTONLK_B_NO_2_XFMR	BARTONLK	▲	4,803	$3,000	$376
3	Chicago_Praxair_13831_flo_WiltonCenter_Dumont765	CHICAGO765 kV	▲	1,727	$4,000	$992
4	SIDOGASIDKEY	SIDNEY	▲	3,278	$1,499	$48
5	NEBS56S40S55	SUB3456	▼	3,197	$1,500	$286
6	NSPALW02_NORTHPRT_NORTHWILMA11_1_1	NORTHPRT	▲	1,854	$2,500	$181
7	TMP636_WARD_BISMARK_230_kV_FLO_CENTER_SQUAREBUTT	WARDWA230 kV	▬	3,218	$1,390	$72
8	BULN_KEL_7363_ftlo_LUTS_NEWMAD_ESEX_345kV	KEL345 kV	▬	2,220	$2,000	$127
9	West_Memphis_AT1_161_500kV_flo_Sans_Souci_Driver	WMPEHV161 kV	▼	2,049	$1,968	$65
10	Anita_Tap_Anita_161_kV_FLO_Macksburg_Winterset_1	ANTA_TP161 kV	▬	2,013	$2,000	$235
11	ALW16041_ABBOTT_ABBOTTRAER16_1_1	ABBOTT	▼	1,299	$3,000	$78
12	Laurel_Jasper_161_flo_Dysart_Traer_161	LAURELSS161 kV	▬	2,570	$1,457	$53
13	TP1025_LN_Ward_Bismark_230_kV_FTLO_LN_Jamestown_	WARDWA230 kV	▬	2,472	$1,490	$126
14	NSP11007_LOONLK_LOONLS3811_1_1	LOONLK	▲	1,313	$2,500	$434
15	CIN23031_DRESSER_DRESS08ALE13_2_1	DRESSER	▼	1,080	$3,000	$1,364
16	Crete_St_Johns_Tap_345_kV_l_o_Dum_Wi_Cent_765_kV	ST_JOHN345 kV	▼	1,561	$2,000	$204
17	Indep2_Moorefield_161kV_FLO_Indep2_Pwrln_500kV	INDEP2161 kV	▬	1,146	$2,500	$404
18	BASE_SUNRISE_4434_44	SUNRISE	▬	955	$3,000	$452
19	ALW16X26_WAPELLO_TR91_TR91	WAPELLO	●	807	$3,500	$673
20	Mansfield_Pelican138_FLO_Redbayou_Manscomp230	MANFL7138 kV	▼	1,351	$2,000	$821
21	ALE69060_NLAKEGE0_NLG_WAL_NL	NLAKEGE0	▬	1,307	$2,000	$799
22	Bullion_Kelso_161	KEL161 kV	▼	1,739	$1,495	$73
23	Kokomo_Tipton_West_230_flo_Nucor_Cayuga_345	KOKOMOPS230 kV	▲	1,277	$2,000	$746
24	TMP293_RUGBY230_RUGBY_115kV_flto_RUGBY230_BALTAJ	RUGBY230 kV	▲	1,592	$1,422	$62
25	Batesvill_Hubbl_138kV_flo_Tanners_Creek_Miami_Fo	BATESVIL138 kV	▼	730	$3,000	$944
26	Horn_Lake_Freeport_161kV_flo_Freeport_500_161kV_	HORNLK161 kV	▬	1,071	$2,000	$463
27	Dearborn_Pierce345_l_o_TannersCrk_Miami_Ft___E_B	PIERCE345 kV	▬	2,011	$1,000	$133
28	TMP524_Sheffield_161_69_kV_XF_ftlo_Sheffield_Ham	SHEFFLD1161 kV	▼	1,333	$1,500	$355
29	BASE_FENOCH	INTF: CHARAMB CHARAELSBO11_1 1	▬	2,658	$740	$37
30	ALWAMO03_WOODY_WOODYAPANO16_1_2	WOODY	●	910	$2,000	$294
31	QUADCITY_SUB_91_345_kV_FLO_CORDOVA_SUB_39_345_kV	QUADCITY345 kV	▼	867	$2,000	$513
32	TMP815_AUR1241_RDSPG5_161kV_FTLO_5WASHBR_BEAVER1	AUR1241161 kV	▬	1,098	$1,500	$588
33	TEMP39_LN_Tekamho_Sub_1226_161_kV_FTLO_Raun_Fort	TEKAMHO161 kV	●	1,090	$1,500	$350
34	ALE13133_NLAKEGE0_NLG_WAL_NL	NLAKEGE0	▼	525	$3,000	$1,016
35	BASE_BRIGEN	INTF: BUFFRID BUFFRPIPES11_1 1	▬	2,969	$509	$51
36	CLC23042_MANFL7_MSFLD_PELICAN_A	MANFL7	▬	748	$2,000	$460
37	NDEX	INTF: LET L20D_3 3	▬	372	$4,000	$39
38	AMO34005_FTZT_MCLY-BELU-1_C	FTZT	●	486	$3,000	$1,692
39	Montgomery_Warrenton_161_flo_Montgomery_Rootbeer	MTGL161 kV	●	482	$3,000	$1,506
40	TP1281_OAHE_FTTHOMP_230kV_CKT_3_ftlo_OAHE_FTTHOM	FTTHOMP230 kV	▬	910	$1,474	$219
41	WEC13332_NLAKEGE1_65411_65	NLAKEGE1	▼	1,338	$1,000	$122
42	TMP430_Maryvil_Midway_161_kV_ftlo_Nodaway_Gentry	MIDWAY5161 kV	▲	871	$1,500	$455
43	HE16003_BATESVIL_BATESNAPOL13_1_1	BATESVIL	▲	1,231	$1,000	$88
44	ALW16041_M_TOWN_M_TOWTIMBR16_1_1	M_TOWN	▬	611	$2,000	$140
45	Clay_500_161_KV_TR_BK_FLO_West_Point_Clay_500_KV	8CLAY_MS500 kV	●	605	$2,000	$73
46	ALENSP1_WIL_RVR_WIL_RKING11_1_1	WIL_RVR	▬	240	$5,000	$671
47	MET13041_COBB_COBBWHITE13_2_1	COBB	▬	1,162	$1,000	$208
48	FORMAN_FORMAN_115kV_TIE_FLO_HANKSON_WAHPETON_230	FORMAN115 kV	▲	817	$1,402	$338
49	ALEWEC02_ROCKDAL1_66320_66	ROCKDAL1	▼	375	$3,000	$557
50	Overton_345_161_xfmr_flo_McCredie_Overton_345	OVER345 kV	▲	528	$2,000	$457
51	Sugar_Creek_Dresser_345_flo_Nucor_Cayuga_345	DRESSER345 kV	▬	526	$2,000	$369
52	CEALW01_NORWGNCK_X-164_1	NORWGNCK	▼	350	$3,000	$525
53	Batesvil_EastBatesville161_flo_Batesvil_Oxford16	5BATESVI161 kV	▲	525	$2,000	$159
54	ITC12X66_LINCN_LINCNL_NE_12_1_1	LINCN	▬	342	$3,000	$1,623
55	Comstock_Miner_161kV_flo_New_Madrid_Essex_Lutesv	MINR161 kV	▬	506	$2,000	$551
56	Raun_Tekamho_161kV_ftlo_Raun_Ft_Cal_345kV	RAUN161 kV	▲	664	$1,500	$352
57	AEPCE01_ROXANA_13835_A	ROXANA	▬	325	$3,000	$1,273
58	IPL13093_STOUT_132-05_1	STOUT	▬	956	$1,000	$33
59	WPS34003_ST_LAKE_TR9_TR9	ST_LAKE	▬	453	$2,000	$628
60	Adams_BeaverCreek_161kV_flo_BriggsRd_NorthRoches	BVR_CRK161 kV	▬	449	$2,000	$595

SPP — Plains

Wind-heavy and export-constrained: the Plains bind where Kansas, Oklahoma and Nebraska wind tries to leave its pocket. Named by flowgate; the monitored line and contingency are in the data.

Captive-power index2026-06 → 2026-09+14% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	TMP630_33215	POTTER_S	▬	7,533	$1,500	$37
2	TP1185_33094	MAHONEY → OXY_BRU	▼	6,263	$1,497	$37
3	TMP336_31246	DUNCAN	▼	4,647	$1,500	$351
4	TP1191_32124	NOWST1	▼	3,873	$1,500	$792
5	OSAWEBCLESOO	OSAGE_OG → WEBBTAP4	▲	3,333	$1,500	$281
6	SIDOGASIDKEY	SIDNEY → OGALALA	▲	3,325	$1,499	$50
7	TMP128_29363	RUSSETT → SBROWN	▼	3,210	$1,500	$567
8	NEBS56S40S55	NEBRCTY → SUB3456	▼	3,166	$1,500	$349
9	TP1214_32539	DUNCAN	●	2,828	$1,500	$382
10	TP1004_31531	WMPEHV	▬	1,982	$1,968	$65
11	BRKXF2BRKXF1	BROOK_LN	▲	2,404	$1,500	$410
12	TP1177_32125	ANTA_TP → ANITA	▬	1,746	$2,000	$307
13	TEMP90_26027	MONETT → AUR1241	▲	2,212	$1,500	$359
14	TP1136_32015	GORD → MAIZ	▲	2,181	$1,500	$333
15	TP1273_33162	MANFL7 → CLEC_PEL	▼	1,359	$2,000	$789
16	TMP338_28287	STILWELL → REDEL5	▼	1,734	$1,500	$384
17	TMP918_33023	BULN → KEL	▬	1,789	$1,400	$69
18	TMP494_32742	BULN → KEL	▬	2,143	$1,167	$80
19	TMP526_32666	SEMINOLE → MAUD_TAP	▼	1,532	$1,489	$220
20	TMP293_28340	RUGBY230 → RUGBY	▲	1,508	$1,422	$59
21	TMP832_33126	SUGR_CRK → SUB_H	▬	1,428	$1,500	$961
22	SMKSUMPOSAXT	WR_SMKHL → SUMM	▬	3,384	$633	$62
23	TP1152_33184	T_BRMGHM → LBRTYST5	▼	1,354	$1,500	$677
24	TMP524_25655	SHEFFLD1	▼	1,310	$1,500	$331
25	TMP777_28815	FIRSTCRK → ROANRDGE	▲	1,284	$1,500	$635
26	TMP459_32122	N345 → BLACKBRY	▬	1,289	$1,474	$167
27	TP1025_33069	WARDWA → BISMARK2	▬	1,267	$1,494	$107
28	JECAUBHOYJEC	JEFF → AUBU	▼	1,178	$1,500	$73
29	TP1281_33195	OAHE → FTTHOMP	▬	1,165	$1,500	$259
30	TMP815_32602	AUR1241 → RDSPG5	▬	1,127	$1,500	$607
31	TMP289_28265	MIDJ	▼	1,077	$1,500	$94
32	TMP784_28847	LAURELSS → JASPER2	▬	1,090	$1,457	$49
33	TMP845_30027	MARSHAL3 → KNOB	▼	2,062	$697	$39
34	CIMXF2CIMXF3	CIMARRON	▼	952	$1,500	$254
35	TMP555_29231	POTTER_S	▬	946	$1,497	$69
36	TMP908_29620	29EVENG3 → 29GA	●	904	$1,500	$653
37	TMP309_33289	6_ME4 → SW51	▼	878	$1,500	$981
38	TP1154_32011	NOWST1	▲	865	$1,500	$1,188
39	TP1241_33286	MDWST → FRNKLN1	▼	853	$1,500	$348
40	AESBONAESTAR	AES5 → BONTP	▲	1,151	$1,094	$38
41	TP1090_31933	FTSMTH	▼	831	$1,500	$422
42	TMP889_32879	STARRDTP → BRNTP	▬	2,005	$616	$36
43	WASSWSLESGRA	WASHIT1 → SW_STA	▬	2,011	$607	$67
44	TMP430_26604	MRYVL_SJ → MIDWAY5	▲	796	$1,500	$439
45	TMP764_33249	MDWST → FRNKLN1	▼	789	$1,500	$419
46	TP1134_32007	WEAV → TALLGRAS	▼	787	$1,500	$1,097
47	TEMP39_26016	TEKAMHO → SUB1226	●	776	$1,500	$431
48	TMP783_32985	PIKE → CYRENE_T	●	582	$2,000	$724
49	TEMP62_32032	DOVRT → TURCRK2	▬	822	$1,410	$411
50	FORTIEHANWAH	FORMAN → FORMNWA	▲	785	$1,465	$335
51	VINHAYKNOXFR	VINETAP3 → NHAYS	▼	762	$1,500	$517
52	TMP278_25759	OVER	▲	571	$2,000	$405
53	TMP314_33281	BROOKNGS → AURORAWA	▼	756	$1,500	$920
54	TMP270_23432	CLEVLND7 → CLEV_AEC	▼	773	$1,466	$224
55	FULPATNWTTUR	FULTON_C → PAT_WX	▲	746	$1,500	$187
56	TP1218_33098	BROOKNGS → AURORAWA	▬	707	$1,500	$927
57	TP1176_33207	CAMPBLCO → GLNHAMWP	▬	803	$1,275	$69
58	TP1078_31925	CLARTOK4 → AMC_TAP	●	1,066	$956	$86
59	TMP277_33234	MAUD_TAP → EARLSBRH	▼	657	$1,500	$728
60	TMP827_32420	OVER	▬	492	$2,000	$513

CAISO — California

Branch and nomogram constraints from the real-time market — the 500 kV import paths and the 115/230 kV pockets where solar and imports run into limits. Siting friction in California is mostly permitting, but the captive-power logic still applies inside a bound pocket.

Captive-power index2026-06 → 2026-09-18% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	22208_EL CAJON_69.0_22408_LOSCOCHS_69.0_BR_1 _1	EL CAJON → LOSCOCHS69 kV	▼	13,857	$4,176	$144
2	34116_LE GRAND_115_34115_ADRA TAP_115_BR_1 _1	LE GRAND → ADRA TAP115 kV	▲	13,403	$2,091	$47
3	7690-CONTRL-INYOKN_EXP_NG	7690-CONTRL-INYOKN	▬	7,882	$2,977	$502
4	31336_HPLND JT_60.0_31370_CLVRDLJT_60.0_BR_1 _1	HPLND JT → CLVRDLJT60 kV	▲	14,148	$1,476	$260
5	33541_AEC_TP1 _115_33540_TESLA _115_BR_1 _1	33541	▼	5,036	$3,129	$135
6	7820_TL649A_OVERLOAD_NG	7820	▼	3,482	$2,716	$85
7	7690-COOLWATER_KRAMER_IM_NG	7690-COOLWATER	▲	4,469	$2,043	$217
8	39021_SC21ATP _70.0_34888_ARVIN _70.0_BR_1 _1	SC21ATP → ARVIN70 kV	▼	2,505	$3,422	$758
9	30750_MOSSLD _230_30797_LASAGUIL_230_BR_1 _1	MOSSLD → LASAGUIL230 kV	▲	5,058	$1,494	$182
10	OMS_19695948_DEV_RDB_ALIS	OMS	▼	7,567	$932	$23
11	34418_KINGSBRG_115_34428_CONTADNA_115_BR_1 _1	KINGSBRG → CONTADNA115 kV	▲	3,384	$1,741	$82
12	34101_CERTANJ2_115_34116_LE GRAND_115_BR_1 _1	CERTANJ2 → LE GRAND115 kV	▲	2,270	$2,390	$155
13	7820_TL 230S_OVERLOAD_NG	7820	▲	3,270	$1,494	$107
14	24701_KRAMER _230_24601_VICTOR _230_BR_2 _1	KRAMER → VICTOR230 kV	▼	8,876	$492	$84
15	30060_MIDWAY _500_24156_VINCENT _500_BR_2 _3	MIDWAY → VINCENT500 kV	▼	2,378	$1,493	$69
16	34002_SALADO _60.0_34008_STNSLSRP_60.0_BR_1 _1	SALADO → STNSLSRP60 kV	▼	3,680	$850	$20
17	35202_USWP-WKR_60.0_33777_SBTAP _60.0_BR_1 _1	USWP-WKR → SBTAP60 kV	▼	11,462	$225	$67
18	34860_TAFT _70.0_34943_Q356TAP _70.0_BR_1 _1	TAFT → Q356TAP70 kV	▬	11,015	$215	$27
19	34548_KETTLEMN_70.0_34552_GATES _70.0_BR_1 _1	KETTLEMN → GATES70 kV	▼	9,258	$235	$119
20	7430_CP6_NG	7430	▲	2,055	$1,020	$102
21	30765_LOSBANOS_230_30790_PANOCHE _230_BR_2 _1	LOSBANOS → PANOCHE230 kV	▲	2,120	$966	$181
22	34471_SNJQJCT _70.0_34469_GFFNJCT _70.0_BR_1 _1	SNJQJCT → GFFNJCT70 kV	▲	8,915	$184	$24
23	34112_EXCHEQUR_115_34116_LE GRAND_115_BR_1 _1	EXCHEQUR → LE GRAND115 kV	▲	4,477	$346	$31
24	22640_PENDLETN_69.0_22708_SANLUSRY_69.0_BR_1 _1	PENDLETN → SANLUSRY69 kV	▲	1,176	$1,276	$82
25	34366_SANGER _115_34370_MC CALL _115_BR_3 _1	SANGER → MC CALL115 kV	▼	253	$4,206	$416
26	38615_DS AMIGO_230_30790_PANOCHE _230_BR_1 _1	DS AMIGO → PANOCHE230 kV	▲	989	$995	$298
27	35658_LS ESTRS_115_35659_NORTECH _115_BR_1 _1	LS ESTRS → NORTECH115 kV	▼	662	$1,455	$360
28	34321_MCSWAINJ_70.0_34232_EXCHEQUR_70.0_BR_1 _1	MCSWAINJ → EXCHEQUR70 kV	▼	552	$1,549	$113
29	31334_CLER LKE_60.0_31338_KONOCTI6_60.0_BR_1 _1	CLER LKE → KONOCTI660 kV	▬	804	$1,015	$347
30	22773_BAY BLVD_69.0_22604_OTAY _69.0_BR_2 _1	BAY BLVD → OTAY69 kV	▼	572	$1,348	$55
31	OMS20246514-CONTRL-INYOKN_EXP_NG	OMS20246514-CONTRL-INYOKN	▬	510	$1,491	$414
32	34321_MCSWAINJ_70.0_34230_MRCDFLLS_70.0_BR_1 _1	MCSWAINJ → MRCDFLLS70 kV	▼	480	$1,569	$204
33	34540_HENRITTA_70.0_30881_HENRIETA_230_XF_4	HENRITTA → HENRIETA70 kV	▼	8,363	$88	$25
34	30790_PANOCHE _230_30900_GATES _230_BR_2 _1	PANOCHE → GATES230 kV	▼	1,577	$448	$77
35	7820_TL23040_IV_SPS_NG	7820	▼	646	$1,090	$127
36	34774_MIDWAY _115_34225_BELRDG J_115_BR_1 _1	MIDWAY → BELRDG J115 kV	▬	211	$3,177	$138
37	22831_SYCAMORE_138_22832_SYCAMORE_230_XF_1	SYCAMORE138 kV	●	451	$1,471	$330
38	24601_VICTOR _230_24085_LUGO _230_BR_4 _1	VICTOR → LUGO230 kV	▼	182	$3,617	$119
39	34009_CRWCRKSS_60.0_34016_CRWS LDS_60.0_BR_1 _1	CRWCRKSS → CRWS LDS60 kV	▬	539	$1,198	$264
40	6110_COI_N-S	6110	▬	1,089	$592	$22
41	33916_CURTISS _115_33917_FBERBORD_115_BR_1 _1	CURTISS → FBERBORD115 kV	●	1,634	$394	$61
42	32218_DRUM _115_32244_BRNSWKT2_115_BR_2 _1	DRUM → BRNSWKT2115 kV	▲	467	$1,360	$232
43	34873_Q484TP _70.0_34850_BLACKWLL_70.0_BR_1 _1	Q484TP → BLACKWLL70 kV	▬	649	$962	$48
44	30515_WARNERVL_230_30800_WILSON _230_BR_1 _1	WARNERVL → WILSON230 kV	▬	564	$1,057	$133
45	VC_TL_681B_import_NG	VC	▼	1,251	$472	$8
46	29400_ANTELOPE_500_29402_WIRLWIND_500_BR_1 _1	ANTELOPE → WIRLWIND500 kV	▬	815	$651	$65
47	MIGUEL_BKs_MXFLW_NG	MIGUEL	▬	358	$1,443	$177
48	24114_PARDEE _230_24115_PASTORIA_230_BR_1 _1	PARDEE → PASTORIA230 kV	●	453	$1,116	$71
49	34724_KRN OL J_115_34736_MAGUNDEN_115_BR_1 _1	KRN OL J → MAGUNDEN115 kV	▼	488	$1,000	$79
50	30060_MIDWAY _500_24156_VINCENT _500_BR_1 _1	MIDWAY → VINCENT500 kV	▼	369	$1,191	$58
51	30060_MIDWAY _500_29402_WIRLWIND_500_BR_1 _2	MIDWAY → WIRLWIND500 kV	▼	604	$673	$36
52	7760_DEV_RDB_ALIS	7760	●	651	$616	$75
53	22773_BAY BLVD_69.0_22352_IMPRLBCH_69.0_BR_1 _1	BAY BLVD → IMPRLBCH69 kV	▬	280	$1,344	$328
54	30765_LOSBANOS_230_30766_PADR FLT_230_BR_1 _1	LOSBANOS → PADR FLT230 kV	●	3,133	$116	$36
55	34930_MC FRLND_70.0_34932_WASCO _70.0_BR_1 _1	MC FRLND → WASCO70 kV	▼	244	$1,475	$675
56	24091_MESA CAL_230_24076_LAGUBELL_230_BR_2_1	MESA CAL → LAGUBELL230 kV	▼	234	$1,475	$518
57	99254_J.HINDS2_230_24806_MIRAGE _230_BR_1 _1	J.HINDS2 → MIRAGE230 kV	●	212	$1,491	$401
58	22192_DOUBLTTP_138_22300_FRIARS _138_BR_1 _1	DOUBLTTP → FRIARS138 kV	▼	202	$1,426	$592
59	33936_MELNS JB_115_33951_VLYHMTP1_115_BR_1 _1	MELNS JB → VLYHMTP1115 kV	●	274	$1,000	$124
60	115kv ML	115kv ML	▼	185	$1,380	$926

NYISO — New York

The classic captive-power story: upstate and Pennsylvania generation trying to reach New York City (Zone J) through a finite set of 345 kV and 138 kV paths. The binding facilities below — Dunwoodie–Shore Road, Goethals–Gowanus, Astoria Annex, Sprainbrook — are where that flow is clipped; load placed on the trapped side of a persistently binding facility is load the grid wants.

Captive-power index2026-06 → 2026-09-51% severity per interval vs prior month

#	Constraint	Corridor	Trend	Binds	Max $/MW	Avg $/MW
1	MEYER 230 MEYER 1 1	MEYER230 kV	▲	4,469	$4,000	$163
2	DUNWODIE 345 SHORE_RD 345 1	DUNWODIE → SHORE_RD345 kV	▼	2,672	$4,000	$53
3	ELWOOD 69 PULASKLI 69 1	ELWOOD → PULASKLI69 kV	▼	1,642	$4,000	$377
4	FOXHILLS 138 GREENWD 138 1	FOXHILLS → GREENWD138 kV	▲	1,268	$4,000	$165
5	GOETHALS 230 LINDEN 230 1	GOETHALS → LINDEN230 kV	▼	870	$4,000	$69
6	SPRNBRK 345 UNIONHBS 345 1	SPRNBRK → UNIONHBS345 kV	▼	847	$4,000	$38
7	STEWRTAV 138 VALLYSTR 138 2	STEWRTAV → VALLYSTR138 kV	▼	782	$4,000	$94
8	GOETHALS 345 GOWANUS 345 1	GOETHALS → GOWANUS345 kV	▲	745	$4,000	$134
9	CHEMUNG 115 NWAVERLY 115 1	CHEMUNG → NWAVERLY115 kV	●	695	$4,000	$516
10	ASTANNEX 345 E13THSTA 345 1	ASTANNEX → E13THSTA345 kV	▬	483	$4,000	$80
11	NEWBRDGE 138 STEWRTAV 138 3	NEWBRDGE → STEWRTAV138 kV	▼	448	$4,000	$509
12	FOXHILLS 138 GREENWD 138 2	FOXHILLS → GREENWD138 kV	▬	389	$4,000	$478
13	SCRIBA 345 VOLNEY 345 1	SCRIBA → VOLNEY345 kV	▼	3,910	$250	$50
14	NEWBRDGE 138 STEWRTAV 138 2	NEWBRDGE → STEWRTAV138 kV	▬	349	$2,500	$143
15	GORDONRD 230 ROTTRDAM 230 1	GORDONRD → ROTTRDAM230 kV	▼	138	$4,000	$510
16	CRICKVLY 345 PLSNTVLY 345 1	CRICKVLY → PLSNTVLY345 kV	▲	610	$819	$58
17	GREENBSH 115 REGENRON 115 1	GREENBSH → REGENRON115 kV	▬	124	$4,000	$369
18	DEPOSIT 69 INDIANHD 69 1	DEPOSIT → INDIANHD69 kV	▼	405	$600	$69
19	GOWANUS 138 GREENWD 138 1	GOWANUS → GREENWD138 kV	▬	389	$600	$52
20	NRTHPORT 138 PILGRIM 138 3	NRTHPORT → PILGRIM138 kV	▼	915	$250	$64
21	SPR/DUN-SOUTH	SPR/DUN-SOUTH	▬	53	$4,000	$184
22	BARRETT 138 VALLYSTR 138 2	BARRETT → VALLYSTR138 kV	▬	182	$1,134	$158
23	MOTTHAVN 345 RAINEY 345 1	MOTTHAVN → RAINEY345 kV	▬	50	$4,000	$156
24	NRTHPORT 138 PILGRIM 138 2	NRTHPORT → PILGRIM138 kV	▼	554	$250	$44
25	ASTORIAW 138 HELLGATE 138 1	ASTORIAW → HELLGATE138 kV	▲	273	$426	$19
26	BUCHAN_N 345 BUCHAN_N 138 1	BUCHAN_N345 kV	▼	29	$4,000	$2,210
27	ALCOA 115 ALCOA_PA 115 1	ALCOA → ALCOA_PA115 kV	▬	68	$1,500	$311
28	NRTHPORT 138 PILGRIM 138 1	NRTHPORT → PILGRIM138 kV	▼	294	$250	$125
29	OAKWOOD 138 SYOSSET 138 1	OAKWOOD → SYOSSET138 kV	▼	254	$250	$99
30	ASTANNEX 138 ASTORIAE 138 1	ASTANNEX → ASTORIAE138 kV	▼	243	$250	$13
31	E13THSTA 345 FARRAGUT 345 1	E13THSTA → FARRAGUT345 kV	▼	375	$143	$7
32	QUAKERRD 115 STA_56 115 1	QUAKERRD → STA_56115 kV	▬	84	$600	$100
33	PANNELRG 115 STA_56 115 1	PANNELRG → STA_56115 kV	▬	82	$600	$184
34	ELWOOD 138 GREENLWN 138 1	ELWOOD → GREENLWN138 kV	▼	182	$250	$205
35	GOETHALS 345 GOWANUS 345 2	GOETHALS → GOWANUS345 kV	▬	111	$314	$34
36	COLTON 115 FLATROCK 115 1	COLTON → FLATROCK115 kV	▬	64	$410	$219
37	HOLTS_8G 69 W_YAPHNK 69 1	HOLTS_8G → W_YAPHNK69 kV	●	11	$1,500	$1,077
38	FRESHKLS 138 WILLWBRK 138 1	FRESHKLS → WILLWBRK138 kV	▲	89	$114	$4
39	GREENLWN 138 SYOSSET 138 1	GREENLWN → SYOSSET138 kV	▼	33	$250	$198
40	TAYLORVL 115 WATERSRD 115 1	TAYLORVL → WATERSRD115 kV	▬	14	$486	$210
41	HARSNRAD 115 HINMAN 115 1	HARSNRAD → HINMAN115 kV	▬	69	$43	$3
42	SHOREHAM 138 WILDWOOD 138 2	SHOREHAM → WILDWOOD138 kV	▼	5	$600	$192
43	DUNWODIE 345 DUNWOODN 345 1	DUNWODIE → DUNWOODN345 kV	▬	14	$191	$64
44	E179THST 138 HELLGATE 138 1	E179THST → HELLGATE138 kV	▬	39	$38	$16
45	CENTRAL EAST - VC	CENTRAL EAST - VC	▬	27	$47	$27
46	MILLWOOD 345 EASTVIEW 345 1	MILLWOOD → EASTVIEW345 kV	●	17	$41	$14
47	RAINEY 138 VERNON 138 1	RAINEY → VERNON138 kV	▼	175	$4	$0
48	BUFALO78 115 HUNTLEY 115 1	BUFALO78 → HUNTLEY115 kV	▬	208	$2	$0
49	NIAGARA 230 PACKARD 230 1	NIAGARA → PACKARD230 kV	▬	31	$13	$4
50	ROSLYN 138 STEWRTAV 138 1	ROSLYN → STEWRTAV138 kV	▼	10	$29	$25
51	BARRETT 138 VALLYSTR 138 1	BARRETT → VALLYSTR138 kV	▬	1	$99	$99
52	MILTR210 115 SUMMIT97 115 1	MILTR210 → SUMMIT97115 kV	▬	33	$0	$0
53	HUDS_AVE 138 JAMAICA 138 1	HUDS_AVE → JAMAICA138 kV	▬	10	$0	$0
54	ASTORIAW 138 QUENBRDG 138 1	ASTORIAW → QUENBRDG138 kV	▬	1	$0	$0
55	BUFAL129 115 MAPLE140 115 1	BUFAL129 → MAPLE140115 kV	▬	1	$1	$1
56	NEWBRDGE 138 RULAND 138 1	NEWBRDGE → RULAND138 kV	▬	2	$0	$0
57	E179THST 138 SHERMCRK 138 1	E179THST → SHERMCRK138 kV	▬	15	$0	$0

Dataset updated October 2026. Screening estimates derived from public data sources.

ERCOT: SCED binding-constraint disclosures (shadow prices & overloaded elements). PJM: Data Miner 2 real-time marginal value (five-minute binding constraints; shadow-price magnitude). NYISO: public real-time limiting-constraint files (constraint cost = shadow price, 5-minute intervals). MISO: daily real-time binding-constraint reports (preliminary shadow prices, 5-minute events). SPP: RTBM binding-constraint files. CAISO: OASIS real-time nomogram and branch shadow prices. Station codes are ISO electrical buses. Non-ISO utilities in the Southeast and West have no nodal prices to read — the bottleneck signal is qualitative there. A screening signal of where captive power sits — confirm deliverable capacity with an interconnection study.