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Website · About · Legal · Privacy · Changelog · © 2026 Parisi Labs
  1. Home
  2. /Assets
  3. /Interties
  4. /ERCOT East DC tie
ERCOT logo

ERCOT East DC tie

ERCOT ↔ SPP · Back-to-back HVDC converter

A back-to-back converter at Welsh in northeast Texas, ERCOT's larger link to SPP and the Eastern Interconnection.

Now
202 MWERCOT → SPP
ERCOT · as of Sep 26, 1:22 PM CDT
Between
ERCOT and SPP
Technology
Back-to-back HVDC converter
Rating
600 MW
Published by
ERCOT
Open on the map

What it is carrying

Each operator's own reading, turned into a direction. Where both markets publish the tie, the two should agree.

As ERCOT reports it
202 MW · ERCOT → SPP

as of Sep 26, 1:22 PM CDT

Price across the seamReal-time · CDT
Reading prices…

Last 30 days

Hourly flow, signed so that up is power leaving the market.

As ERCOT reports it202MW
7085-697Aug 27, 2 PMSep 26, 1 PM

Above zero: ERCOT → SPP. Below: the reverse.

Hardware

Its terminals. US terminals are placed on the substation HIFLD's national dataset names for them.

Converter
Welsh, TX

Not in HIFLD's dataset

Related interties

  • ERCOT North DC tie
    ERCOT ↔ SPP
  • Laredo VFT
    ERCOT ↔ Mexico (CFE)
  • Railroad DC tie
    ERCOT ↔ Mexico (CFE)
  • Eagle Pass DC tie
    ERCOT ↔ Mexico (CFE)
  • MISO–SPP seam
    MISO ↔ SPP
Usual direction
SPP → ERCOT in 40% of hours

22% out, 40% in, 38% idle across 720 hours

Average
62 MW · SPP → ERCOT
When busy
600 MW

95th percentile of hourly flow either way

Peak ERCOT → SPP
611 MW
Peak SPP → ERCOT
600 MW
Direction changes
48
Hours near its rating
70 of 720

At 95% or more of 600 MW

The average day
0:006:0012:0018:0023:00
Mean flow by the market's local hour. Up: ERCOT → SPP. Down: SPP → ERCOT.