Dive Brief:

• A possible sign of thawing emerged in the tense relationship between regional transmission system operators Southwest Power Pool and the Midcontinent Independent System Operator (MISO) when they agreed to consider $276 million in transmission construction.
• Under a joint model for identifying congested flowgates that could be relieved by economic projects, MISO and SPP are studying four potential projects that could bring them $438 million in benefits over 20 years, according reporting from RTO Insider.
• Talks on the four projects are the first significant cooperation between the RTOs since MISO lured Entergy away from SPP and into its membership in December 2013. Entergy had been an SPP participant since 2006.

Dive Insight:

The most recent MISO-SPP dispute was sparked when power flows between MISO’s northern region and a new, southern region caused complaints last spring from SPP that MISO was moving more than the contracted 1,000 MW over the SPP footprint.

But now it appears that the two regional grid operators are setting aside their past differences to work on new transmission projects.

Through their new cooperation, SPP and MISO stakeholders and staff identified 67 potential economic projects to meet modeled transmission needs for 2019 and 2024, then settled on the four that provide the minimum 5% congestion reduction benefit:

• Alto-Swartz 115 kV series reactor
• S. Shreveport-Wallace Lake 138kV, 11 mile line (rebuilt)
• Elm Creek-Mark Moore 345kV, 100 mile line (new)
• Elm Creek-NSUB 345kV, 78 mile line (new)

Combined, the RTOs expect the projects will deliver $438.2 million in benefits, for $275.8 million in costs. MISO and SPP have also initiated discussions of a study of potential impacts from the proposed Environmental Protection Agency Clean Power Plan.

MISO, the first U.S. RTO, was established by a group of transmission operators in 1998 and was approved by the Federal Energy Regulatory Commission (FERC) in December 2001. It delivers electric power across all or parts of 15 U.S. states and Canada's Manitoba.

SPP was formed in 1941 when 11 regional power companies joined to keep an Arkansas aluminum factory powered 24/7 to meet critical defense needs. It was approved by FERC as one of North America’s nine RTOs in 2004. It serves 14 states.