Way back in 2021, the Mississippi Public Service Commission (MPSC) opened a docket to evaluate the value of membership at the Midcontinent Independent System Operator (MISO). The PSC recently brought in consulting firm Bates White to examine the numbers and assess whether or not Mississippi benefits from staying in MISO.
The result? Mississippi benefits from staying in MISO.
Bates White’s analysis found that these benefits have held up over time, consistent with the Commission’s earlier findings in 2012 and 2018. Mississippi families and businesses pay lower bills than the national average, helping to keep electricity affordable while also attracting major new employers, like the 1,000 megawatt (MW) Amazon Web Services data center now planned for Entergy Mississippi’s (EML) territory.
While MISO provides significant benefits, SREA has noted that all too often, Commission staff and expensive outside consultants have slowed or opposed MISO improvements, leaving the state reactive instead of proactive on things like Long Range Transmission Planning (LRTP). Working with MISO, instead of against, could potentially lead to even greater benefits for the Magnolia State.
No, MISO isn’t perfect. MISO South has been waiting for over a decade for truly regional transmission planning. A paper by the National Bureau of Economic Research found that better transmission connections would reduce costs in MISO South by about $850 million.
Transmission constraints not only increase costs, but also harm reliability. Just a few months ago, New Orleans experienced power outages, partly because of a lack of transmission planning. The Bates White report doesn’t seem to mention these real and ongoing problems, but instead discusses some hypothetical transmission costs. SREA’s position has been clear: the status quo isn’t free, and it’s better to proactively plan for the future.
Despite these shortcomings, MISO is better than the alternatives.
Some have suggested leaving MISO for the Southwest Power Pool (SPP), or joining looser arrangements like SPP’s Markets+ or the Southeast Energy Exchange Market (SEEM). Bates White found none of these to be realistic or superior options for Mississippi today.
- SPP membership would almost necessitate Arkansas or Louisiana also leaving MISO to enable viable transmission paths
- Markets+ isn’t even available in our region.
- SEEM is a weak alternative, with trade volumes so small they cannot deliver anything close to MISO’s benefits
In short: there is no credible “Plan B” that offers Mississippi the reliability, cost savings, and competitive benefits of staying in MISO. In fact, it’d likely be helpful for Mississippi to evaluate expanding its membership in MISO to include other utilities.
It’s worth remembering why Mississippi joined MISO in the first place. The Department of Justice investigated Entergy’s anti-competitive behavior in the Southeast and effectively pushed the utility to join an RTO to restore competition. MISO membership ensures that all power generation is dispatched independently, at the lowest cost, with transparent oversight.
Leaving MISO would risk reversing these gains, returning the state to a system where utilities can block competition, raise costs, and make opaque planning decisions that hurt consumers.
Staying in MISO has saved Mississippians money, improved reliability, and opened the door for renewable growth and economic development. Even toying with the idea of departing MISO could put at risk billions of dollars of economic development, like the Amazon data center and other manufacturers.
Businesses want access to competitive, but stable and predictable, energy markets. MISO provides that stability. The Bates White report validates that reality.
