Utility Tariff Analysis · Updated September 2026

Special Contracts Under Mississippi PUC Rule 27: What It Means for AI Data Centre Siting in Mississippi

Any large load negotiated under a Public Service Commission-approved special contract can be structured through special contracts between the utility and customer under Rule 27 of the Mississippi Public Utilities Rules of Practice and Procedure, which must be approved by the Public Service Commission and can incorporate minimum billing, financial assurance and exit-fee terms.

Special Contracts Under Mississippi PUC Rule 27 — AI data centre infrastructure

Special Contracts Under Mississippi PUC Rule 27

MS

Entergy Mississippi / Mississippi Power

MS Public Utilities RPP Rule 27

Regulatory docket / filing reference

Any large load negotiated under a Public Service Commission-approved special contract

Who the tariff applies to

Any large load negotiated under a Public Service Commission-approved special contract can be structured through special contracts between the utility and customer under Rule 27 of the Mississippi Public Utilities Rules of Practice and Procedure, which must be approved by the Public Service Commission and can incorporate minimum billing, financial assurance and exit-fee terms.

Also active in Mississippi: Mississippi's pipeline is exceptionally large relative to the state's size: Entergy Mississippi is serving a $21 billion, two-complex AWS commitment projected to deliver $2 billion in net benefits including $1.3 billion in generation-cost savings, and Mississippi Power is serving a $10 billion, roughly 500 MW Compass Datacenters campus in Meridian.

Named Projects Already Underway

CustomerLocationDetails
AWSMadison County, MS$21 billion investment across two data centre complexes; project to contribute $2 billion in net benefits including $1.3 billion in generation-cost savings and $700 million in fuel-cost savings
Compass DatacentersMeridian, MS$10 billion data centre campus, approximately 500 MW across eight buildings

Figures compiled from the Edison Electric Institute's "Large Load Projects and Tariffs" (September 2026) member-company summary and public regulatory filings. Confirm current tariff terms directly with Entergy Mississippi / Mississippi Power and the relevant state public utility commission before relying on any figure for a capital decision.

Weighing Mississippi against another state or a Canadian province with a different rate and interconnection picture entirely? Run both sides of the comparison through our licensed AI data centre cost configurator — it applies each jurisdiction's actual power rate, tax treatment and large-load tariff rules to the same seven build configurations.

Model This State on Your Own Site

Every figure above comes from the same power-cost and tariff dataset behind the SCR AI Build Configurator — a licensed, embeddable widget that models seven data centre build configurations against all nine Canadian provinces and all 50 US states plus DC, returning capital expenditure by line item, energy cost, revenue by commercial structure, EBITDA and payback.

LicencePrice (CAD)Who it suits
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Not ready for an annual licence? A one-time Site Screening Report ($950, one site) runs the same model for a single build without embedding anything.

Frequently Asked Questions

What is Special Contracts Under Mississippi PUC Rule 27?

Any large load negotiated under a Public Service Commission-approved special contract can be structured through special contracts between the utility and customer under Rule 27 of the Mississippi Public Utilities Rules of Practice and Procedure, which must be approved by the Public Service Commission and can incorporate minimum billing, financial assurance and exit-fee terms.

Why did Entergy Mississippi / Mississippi Power introduce this large-load structure?

To ensure the cost of new generation, transmission and distribution infrastructure built to serve very large customers, chiefly hyperscale data centres, is paid for by those customers rather than spread across the general rate base of residential and small commercial ratepayers.

What large data centre projects are already active in Mississippi?

Mississippi's pipeline is exceptionally large relative to the state's size: Entergy Mississippi is serving a $21 billion, two-complex AWS commitment projected to deliver $2 billion in net benefits including $1.3 billion in generation-cost savings, and Mississippi Power is serving a $10 billion, roughly 500 MW Compass Datacenters campus in Meridian.

Does this tariff replace Mississippi's standard commercial and industrial rates?

No. Special Contracts Under Mississippi PUC Rule 27 sits above Entergy Mississippi / Mississippi Power's standard commercial and industrial rate schedules and applies specifically to customers that meet or exceed the large-load threshold described above. Smaller commercial and industrial loads continue to be billed under existing rate schedules.

How can I model a Mississippi data centre build against this tariff and other states?

The SCR AI Build Configurator applies Mississippi's power cost, tax treatment and large-load tariff rules alongside all other US states and Canadian provinces, so a Mississippi scenario can be compared line-by-line against any alternative site.