Legacy Contract Agreements

This market update is also available in Spanish. Click here to view the Spanish version.
 

Today, two agreements issued by the Ministry of Energy (SENER) were published in the Official Gazette of the Federation:

• Agreement issuing the Guidelines for the voluntary and expedited migration of self-supply and cogeneration schemes of electric power to the structures established under the Electricity Sector Law.
   
• Agreement of the National Energy Commission establishing the methodology for determining the charge for the electricity transmission service provided by the Supplier to permit holders with generation plants that have interconnection agreements and transmission service contracts executed under the Public Electricity Service Law (LSPEE).

These agreements aim to regulate the migration of generators and load centers associated with a Legacy Structure (i.e., self-supply or cogeneration permits under the LSPEE), linked to power plants with a capacity equal to or greater than 0.7 MW, as well as the related contracts and agreements currently in force.

Through this measure, SENER seeks to reduce the number of contracts under the LSPEE and promote the transition to the Wholesale Electricity Market (WEM). To do so, interested parties must submit an expression of interest to participate in the migration process. During this period, they may continue operating under the LSPEE, provided they maintain a valid interconnection agreement.

Load centers that are part of self-supply or cogeneration entities may aggregate their demand to obtain one or more registrations as Qualified Users, without requiring a minimum demand per load center. Additionally, consumption centers sharing a private network with a power plant may migrate to the self-consumption modality under the Electricity Sector Law (LSE).

It is important to note that obtaining a permit under the LSE implies the waiver and termination of the legacy permit, while the completion of the migration process results in the early termination of the associated contracts and agreements.

Final users currently receiving supply through Legacy Structures may choose to:

• Migrate to the WEM, or
• Receive supply from the Federal Electricity Commission (CFE).

If they choose not to migrate, they will continue to receive electricity under CFE’s Basic Supply scheme.

Migration options

The available migration modalities are:

1. Power Plant Migration
2. Joint migration of Power Plant and Load Centers to the WEM, where the plant will be represented by a Generator, and load centers may be grouped as Qualified Users represented by a Qualified Services Supplier.
3. Migration of Final Users as Qualified Users, applicable to load centers with an individual or aggregated maximum demand ≥ 1 MW.
4. Migration of Final Users to Basic Supply, for those who choose to remain with CFE.
5. Joint migration to interconnected self-consumption, for power plants and local loads under a coordinated scheme.
6. Joint migration to isolated self-consumption, applicable to power plants with at least one self-consumption user participating in a coordinated manner.

For cases 1, 2, 5, and 6, the timelines and milestones are described in the corresponding guidelines.

For cases 3 and 4, specific stages and deadlines are also established.

The exclusion of load centers from Legacy Structures allows final users to choose between Basic Supply or Qualified Supply according to their interests (Article 13 of the Guidelines). In this context, holders of Legacy Structures must facilitate the exclusion of users requesting to migrate.

Transmission tariff changes

The preferential transmission tariff applicable to legacy contracts will cease to exist on October 19, 2026. From that date onward, the transmission service charge will be calculated using the following formula:

CST_i = ISPTEE_i + ISPDEE_i + ISOCENACE_i + ISCnMEM_i

Where:

• CST_i: Total transmission charge for permit holder i
• ISPTEE_i: Market settlement for transmission service
• ISPDEE_i: Market settlement for distribution service
• ISOCENACE_i: Market settlement for CENACE operation services
• ISCnMEM_i: Market settlement for ancillary services not included in the MEM

This implies the incorporation of regulated tariffs and MEM-related charges that were not previously considered.

However, generators and load centers that choose to migrate will retain their current wheeling (transmission) conditions until October 6, 2028.