Mexico’s National Energy Commission publishes guidelines for the integration of electric energy storage systems

Mexico’s National Energy Commission (CNE)[1] published new guidance titled “General Administrative Guidelines for the Integration of Electric Energy Storage Systems into the National Electric System” (Guidelines) in the Federal Official Gazette on April 16, 2026. Together with the Electricity Sector Law (LSE) and its Regulations (RLSE), the Guidelines comprise the first regulatory framework for the integration, operation, and market participation of Electric Energy Storage Systems (SAEE) in Mexico.

The Guidelines define five modalities of participation that cover power plants, load centers, self-consumption, transmission and distribution infrastructure, and non-associated SAEE. Rules regarding studies, permits, metering, transitory offers, and tariffs are consistent with binding planning, the operational control of the National Energy Control Center (CENACE), and the Market Rules, substituting the provisions of Acuerdo A/113/2024, published in the Federal Official Gazette on March 7, 2025.

This client alert summarizes the provisions and key points for generators, investors, investment funds, and developers who are evaluating the integration of energy storage systems for projects in Mexico’s electricity sector.

Purpose, scope, and regulatory articulation

The Guidelines establish requirements for integrating SAEE into the National Electric System (SEN), guidelines for the services they can provide, modalities of participation, and assumptions for their grouped installation. The Guidelines aim to ensure that integration and operation are orderly, safe, and efficient, and that they contribute to the accessibility, continuity, reliability, quality, safety, efficiency, and sustainability of the SEN.

Technology and technical references

SAEE can employ technologies such as electrochemical storage or batteries, mechanical storage, hydraulic repumping storage, flywheel storage, gravitational storage, thermal storage, compressed air storage, and chemical storage of hydrogen or green ammonia and associated peripherals.

If there is no Official Mexican Standard on the matter, compliance with IEC 62619 and IEC 62933-5-1/5-2 and UL 1973 and UL 9540 standards is required, demonstrable in accordance with the Quality Infrastructure Law. Likewise, an SAEE based on power electronics that inject into the National Transmission Network (RNT) or the General Distribution Networks (RGD) must implement grid-forming technology and submit a request for interconnection studies for injection and, where appropriate, connection for energy withdrawal.

Modalities of participation: Regulatory treatment and operational parameters

The integration of SAEE is conceived as complementary infrastructure and, in itself, does not imply the performance of the regulated storage activity.

The Guidelines provide for the following types of SAEE, each with specific rules for studies, operation, and representation in the Wholesale Electricity Market (MEM):

• SAEE associated with power plants (SAEE-CE): SAEE-CE may be integrated exclusively by renewable energy plants with a generation permit under the figure of Generation for the MEM, which are an integral part of the plant and do not require a storage permit. These systems are treated as a single resource for the commercialization of energy, power, and related services and may operate at the disposal of CENACE or the plant representative, in accordance with the criteria of the Guidelines and the Market Rules. The SAEE power must be less than the net installed capacity and the sum of the maximum injection capacity of the plant and the SAEE may not exceed that which is agreed upon in the interconnection contract, except in the case of new studies, modification of the permit, and contractual adjustment.


• SAEE associated with load centers (SAEE-CC): SAEE-CC is considered part of the load center facilities and does not require a storage permit; its use and operation correspond to the center, integrating the charging power to the contracted or maximum demand without exceeding it and allocating the stored energy exclusively to on-site needs, without injection or sale in the RNT or RGD. Requests are dealt with under the Interconnection and Connection Manual, with studies that analyze base cases of minimum, medium, and maximum demand and consider the impact of the load of the SAEE on the network, being treated as a technical modification for existing centers or with impact studies and installations for new centers.


• SAEE associated with the figure of self-consumption (SAEE-autoconsumo): The Guidelines specify that the installed capacity of SAEE is not added to the generation capacity in the self-consumption permit and that the SAEE can be made up of self-consumption users or holders of self-consumption generation permits, differentiating rules for schemes with and without injection into the grid. In non-injection schemes, the stored energy is used exclusively for its own or the group's needs, with SAEE power equal to or less than the plant's capacity and charges from the plant itself or from the interconnection point not exceeding the plant's capacity or injecting into RNT or RGD. For modalities with injection, interconnection studies are required; the modality should not be injected above the capacity of the plant, but rather incorporate, in variable sources, variability analysis and grid-forming technology.


• SAEE integrated into transmission and distribution infrastructure (SAEE-RNT/RGD): The SAEE-RNT/RGD are elements of the RNT or RGD infrastructure that are the exclusive property of the transmission company or distributor. Their implementation aims to strengthen the public service and maintain the technical attributes of the SEN, without participating in the MEM or associating with particular networks, power stations, or load centers. In addition, SAEE-RNT/RGD are subject to permanent operational coordination by CENACE. The energy that these systems charge, store, and discharge is not subject to payment or consideration of any kind.


• Non-associated SAEE: Non-associated SAEE are not part of a central or load center or of the RNT/RGD infrastructure. They carry out the regulated storage activity, so they require a storage permit that indicates the services they can provide. In addition, they can participate in the MEM as a storage company or be represented by a generator or supplier, submitting a single application for interconnection and connection. These systems can accredit power according to the value of Availability of Physical Delivery evaluated, the type of offer, and the Declaration of Entry into Commercial Operation. When determined by binding planning, they can provide backup coverage to plants that decide not to integrate their own SAEE, under technical specifications of the variability analysis of the plant served.

Interconnection and connection studies and technical criteria

Any SAEE planning to inject energy into the RNT or RGD must request interconnection studies and, when withdrawing energy for loading, connection studies, both of which may be sought using a single request that describes, among other information, technology, capacity, power, response times, and charge and discharge speeds.

MEM operation, measurement, transitory offers, and tariffs

To participate in the MEM, an SAEE must have a metering system at its interconnection or connection point. Offers may be submitted for the purchase and sale of energy and associated products in the Short-Term Energy Market in accordance with the Market Rules, with settlements subject to the Settlement Manual. As long as specific functionalities are not enabled in the market models, the Guidelines provide for transitional schemes: an SAEE-CE incorporates its unloading in the plant's sales offer and, if it loads from the RNT, it presents a fixed purchase offer at the scheduled loading times; an SAEE-CC submits a fixed purchase offer incorporating and discounting, as appropriate, its loading and unloading profile; and a non-associated SAEE submits a fixed purchase offer for loading and a sale offer in thermal format for discharge.

As for regulated charges, the distribution rates apply only for the withdrawal of energy, while those for transmission and the operation of CENACE are applied to an SAEE-CE for the injection and, for non-associated SAEE, to 50 percent of the corresponding rate for both withdrawal and injection, with mechanisms to compensate certain charges being provided in the Market Rules when applicable. For power accreditation, an SAEE with a storage duration equal to or greater than three hours can be accredited in accordance with Market Rules and the Market Manual for Power Balance.

SAEE grouping: Location, studies, and representation

The Guidelines define grouping as the joint integration of an SAEE whose rights and benefits are shared among those who invest. In addition, they provide that the grouping must be located in the same substation, node, or electrical area that CENACE technically determines, in accordance with binding planning instruments or criteria, with socialization of costs of specific works among beneficiaries based on the studies.

The group must appoint a commercial representative and a technical manager jointly and severally with the carrier or distributor, who acts as an interlocutor for CENACE orders and is liable for any damage its operations cause to the networks. If the pooled SAEE participates in the MEM, it is identified as a single resource under the applicable operating regime.

Binding planning and contracting with CENACE

The integration of the SAEE, in any of its modalities, must meet the instruments or criteria of the binding planning of the SEN, which guides location, operational function, and technical requirements. In addition, the Guidelines provide that CENACE may enter into short-, medium-, and long-term contracts with a non-associated SAEE when, as a result of the binding planning process, it is identified that an SAEE constitutes a more efficient alternative to maintain or improve the reliability of the SEN with respect to conventional options. The RLSE also contains broader authorizations that do not expressly limit this contracting power to any non-associated SAEE.

The studies that support these contracts must analyze and identify problems of operation or reliability; nodal and zonal flows, rapid response, and regulation requirements; effects of variability and integration of renewables; contingencies and flexibility needs; technical and economical alternatives; and opportunities in which an SAEE could provide greater value. Contracts are entered into through competitive mechanisms and may incorporate performance and availability obligations in accordance with the technical-economic analysis of reference.

Implementation, transition, and upcoming milestones

The Guidelines enter into force on the business day following their publication, providing that, until the Interconnection and Connection Manual and the Market Rules are updated, requests and offers will be processed in accordance with the instruments in force under specific criteria for SAEE according to their modality. CENACE must publish, within a period of no more than 90 calendar days, the methodology of the Variability Analysis referred to in the Guidelines, with prior authorization from the CNE, and the CNE must publish, within 30 calendar days following the entry into force, the forms for storage permits and for generation permits for an SAEE.

Within the scope of the MEM, the Guidelines establish transitional offers by modality until specific functionalities are enabled in the market models, subject to their replacement by corresponding updates to the Market Rules.

Operational and structuring considerations for projects with SAEE

Although the integration of an SAEE does not require a storage permit in projects associated with power plants or load centers, it may imply modification or migration of the generation permit, updating of the interconnection contract, and obtaining the Declaration of Entry into Commercial Operation – aspects that must be evaluated with the CENACE studies. In any non-associated SAEE, the storage permit must detail the services that the system can provide, including, where appropriate, services provided under contract with CENACE. In addition, participation in the MEM may be direct as a storage company or represented by a generator or supplier.

In technical and connection design, participants are encouraged to define load and discharge profiles, target power and duration, grid-forming requirements, and evaluation under Availability of Physical Delivery and sizing criteria that affect infrastructure costs, study schedules, and power accreditation. In self-consumption schemes with variable sources, participants must remain compliant with CENACE determinations and applicable Guidelines pertaining to technical specifications, expected degradation, and performance obligations over time.

In SAEE-RNT/RGD, the non-market nature of the stored energy and the tariff recognition of inefficiencies and opportunity costs are reflected in the tariff methodology and in the asset management under the operational coordination of CENACE.

For more information, please contact the authors.

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_{[1] All acronyms are referred to in Spanish.}