The Green Expo ran from 3 to 5 September 2024 at Centro Citibanamex in Mexico City. Energía Hoy reported on 24 August 2024 that the thirty-first edition would bring together more than 400 exhibiting companies from 20 countries, organized by Informa Markets, with Aquatech Mexico and Intersolar Mexico running in the same halls. For a plant director walking that floor, the useful question was not which product looked best. It was whether it could be bought, permitted and connected in Mexico inside the next budget year.
On the two categories that drew the most stand space, rooftop solar and battery storage, the answer in September 2024 was set by Mexican rules rather than by the equipment. A generating plant below 0.5 MW connects under the distributed generation regime. At or above 0.5 MW it needs a permit from the Comisión Reguladora de Energía. And the general provisions that would define how a storage system integrates into the Sistema Eléctrico Nacional were still a draft in public consultation.
Those two limits, not module efficiency or cell chemistry, decide what a Mexican plant can put into a quoting round this quarter. What follows sets out where each line sits, what it does to project sizing, and which of the categories on that floor is ready to buy now.
The 0.5 MW line that sizes your roof
Article 17 of the Ley de la Industria Eléctrica, published in the Diario Oficial de la Federación on 11 August 2014, requires a CRE permit for electricity generation plants of 0.5 MW or more. Below that threshold a plant connects as generación distribuida under the disposiciones administrativas CRE issued in RES/142/2017, published in the DOF on 7 March 2017, which also set the contract models and the compensation methodology.
The gap between the two routes is administrative, not technical. Under 0.5 MW you sign an interconnection contract with the distributor and start. At 0.5 MW you enter a permitting process with a filing, a review and a schedule you do not control. A plant with 900 kW of usable roof therefore faces a real design decision, and the cheapest answer is rarely the largest array.
The market data shows how few installations have crossed that line. CRE figures reported by pv magazine México on 14 March 2024 put distributed generation at 3,361.69 MW across 411,085 interconnection contracts at the close of 2023, after 728.93 MW was added during the year. Photovoltaic systems account for 3,339.31 MW, or 99.33% of the capacity. Divide capacity by contracts and the average system is about 8.2 kW. That base is residential and small commercial, and an industrial array at the 0.5 MW ceiling sits at the very top of it.
The practical consequence for a manufacturer is that rooftop solar under this regime covers a slice of load rather than the whole of it. Sizing has to start from the load profile and the tariff, not from the available roof area. Our earlier note on the questions industrial buyers ask about rooftop solar covers the interconnection paperwork in more detail.
Metering pays only when it moves billed demand
Several exhibitors were selling consumption monitoring. On a medium voltage tariff, consumption is not where the money sits. CFE bills GDMTH through seven concepts, and two of them scale with demand in kilowatts rather than with kilowatt hours. The capacity charge is computed on maximum demand measured in the punta period. The distribution charge uses a formula built from monthly consumption, the days in the billing period and the load factor. Marsam Solar set out that structure on 1 March 2022.
Contracted demand also cannot fall below 60% of total connected load, which limits how far a plant can reduce its billed floor by contract alone.
A meter that reports kilowatt hours after the fact does nothing to either charge. What moves them is interval measurement at the point of billing, a record of which machines run together during punta, and a control action that shifts or sheds one of them. Buy the measurement for the demand curve, not for the consumption total. Continuous energy monitoring earns its cost on the kilowatt line or it does not earn it at all.
Storage was on show before the rule was written
Battery systems had a large presence on the floor. The rule that governs how they join the grid did not exist yet. CRE circulated a draft of the disposiciones administrativas de carácter general for the integration of Sistemas de Almacenamiento de Energía Eléctrica into the Sistema Eléctrico Nacional through CONAMER under file 65/0006/060524. The Asociación Mexicana de Energía Solar filed comments on that draft on 10 June 2024. The draft proposed five operating modalities and referenced roughly 13,501 MW of storage capacity contemplated for the period 2024 to 2038.
As of this article's date the provisions had not been published in the DOF. On our read that splits the storage question in two. A battery operated entirely behind the meter to cut measured demand under GDMTH sells nothing into the market and is governed by the plant's own interconnection contract. A battery intended to earn revenue from the Mercado Eléctrico Mayorista had no published rulebook to be permitted under. The first case can be quoted and modeled now. The second cannot be underwritten until the provisions are published.
A buyer taking a battery quote from the expo should ask which of those two cases the vendor is pricing, and should treat any market revenue line in the model as unsupported until the rule exists. Our view of where energy storage actually stands in Mexico sets out the commercial cases that survive that test.
Why the policy backdrop argues for buying inside the fence
SENER's PRODESEN 2024-2038 put clean generation at 24.3% of total generation in 2023, against the 35% share Mexico carries in national law and in its Paris commitment. The same document identified 25,251 MW of capacity additions required between 2024 and 2027, alongside 194 CFE transmission projects and 5,719 km of line planned to 2030, with no expansion for the Yucatán Peninsula. IMCO published that reading on 6 June 2024.
Read against that, the gap between what the country needs to build and what is being built is not something an individual plant can wait out. Assets a manufacturer controls directly, on its own site and under its own interconnection contract, are the ones whose schedule the manufacturer sets. That is the argument for the distributed generation array and the behind the meter battery, and it does not depend on any forecast of federal policy.
What to quote now and what to hold
Four actions follow from the rules above, and three of them can start before the next quoting round.
- Size any rooftop proposal against the 0.5 MW threshold explicitly, and ask the vendor to price both a compliant system and the permitted alternative.
- Specify interval demand measurement at the billing point, and require the vendor to show which GDMTH charge each proposed action reduces.
- Separate battery quotes into behind the meter demand reduction and market participation, and discard the market revenue line for now.
- Hold any storage investment whose return depends on selling services into the Mercado Eléctrico Mayorista until CRE publishes the provisions in the DOF.
A supplier who cannot say which of those four cases its product serves in Mexico is selling a specification sheet rather than a project.
Put what was on that floor into a real quoting round
Mexico Energy Partners screens equipment and supplier options against a specific plant's load profile and tariff, checks which vendors hold a Mexican entity and local stock, and states which options clear the plant's payback threshold. To start, send twelve months of CFE invoices, the plant's connected load list, and the roof or yard area available. We confirm scope and data gaps before any work begins. Use the form below to request a supplier and technology screen for your plant.
Sources
- Energía Hoy, "Es THE GREEN EXPO 2024 la principal plataforma en tecnologías verdes", 24 August 2024. Thirty-first edition, 3 to 5 September 2024 at Centro Citibanamex, more than 400 exhibiting companies from 20 countries, organized by Informa Markets, co-located with Aquatech Mexico and Intersolar Mexico.
- Ley de la Industria Eléctrica, Diario Oficial de la Federación, 11 August 2014. Article 17 on the CRE permit requirement for plants of 0.5 MW or more.
- Comisión Reguladora de Energía, RES/142/2017, disposiciones administrativas de carácter general, contract models, compensation methodology and technical specifications for distributed generation, Diario Oficial de la Federación, 7 March 2017.
- CRE distributed generation statistics reported by pv magazine México, 14 March 2024. 3,361.69 MW across 411,085 contracts at the close of 2023, 728.93 MW added during 2023, photovoltaic capacity of 3,339.31 MW or 99.33% of the total.
- Marsam Solar, "Tarifa GDMTH: qué es, cómo se cobra y cómo influye en tu empresa", 1 March 2022. Seven billing concepts, capacity charge on maximum demand in the punta period, distribution charge formula, and the 60% contracted demand floor.
- Asociación Mexicana de Energía Solar, comments filed with CONAMER on the CRE draft provisions for the integration of electricity storage systems, file 65/0006/060524, 10 June 2024. Five proposed operating modalities and about 13,501 MW of storage contemplated for 2024 to 2038.
- IMCO, analysis of PRODESEN 2024-2038, 6 June 2024. Clean generation at 24.3% of the total in 2023 against the 35% target, 25,251 MW of additions required from 2024 to 2027, 194 CFE transmission projects and 5,719 km of line planned to 2030.