What CFE has announced at Puerto Peñasco
CFE has announced a 1,000 MW photovoltaic project at Puerto Peñasco, Sonora, to be built in phases. The cost and schedule figures circulating for it disagree with one another, and they do not all measure the same quantity. Some are a total project cost, some are peso construction appropriations covering a single phase, and some cover only the associated transmission build. No single number reconciles them, so a figure quoted without its basis is not usable in a business case.
Phase capacities, a battery rating, a transmission line length and a transformation capacity all circulate alongside the headline gigawatt, as do competing accounts of how the associated 400 kV build reaches Baja California. None of them is confirmed by a CFE document available to us, so they are left out here. Ask any supplier who quotes one of these figures which document it came from.
Why transmission, not sunlight, sets the ceiling in Sonora
Sonora already leads Mexico in large-scale solar. NREL's April 2022 assessment, Mexico: North American Clean Energy Powerhouse, puts the state's utility-scale photovoltaic capacity at 1,326 MW in 2021, ahead of Aguascalientes at 907 MW and Chihuahua at 828 MW. The resource is not in question. S&P Global Commodity Insights reported on 6 July 2021 that UNAM research identifies Sonora as having Mexico's largest solar generation potential, and that roughly 1% of the state's territory could in principle supply national power demand. That is a statement about irradiance and land, not about deliverable energy.
Deliverable energy is governed by three institutions, and CFE is only one of them. CENACE operates the Sistema Eléctrico Nacional, dispatches generation, runs the interconnection studies that determine whether a new plant can connect at a given node, and prepares the transmission expansion analysis. SENER issues the PRODESEN, the sector planning program that carries the expansion and modernization program for the Red Nacional de Transmisión. CRE issues the generation permits. CFE is a state productive enterprise and a market participant. It builds and operates, and CFE Transmisión runs the network under CENACE's operational instruction, but it does not approve its own interconnections or set its own tariffs.
That split matters commercially. A generation project in Sonora with no firm interconnection has no contractable output, whoever owns it. Baja California is the clearest illustration. Its grid has run separately from the national interconnected system, which is why the 400 kV build is attached to the plant rather than treated as a later phase.
What this means for a facility in the northwest
Nothing in the Puerto Peñasco program gives an industrial site cheaper power before the transmission is energized, and the first phase delivers only part of the announced 1,000 MW against a national system where NREL projects 2024 demand of 365 TWh. Treat the project as a change to regional supply adequacy over a five-year horizon, not as a procurement option for the next budget cycle.
Three routes are available to a Sonora facility now, and they have different lead times:
- Onsite distributed generation. Generation capacity below 0.5 MW interconnects under the SENER Manual de Interconexión (DOF, 15 December 2016) and CRE resolución RES/142/2017 (DOF, 7 March 2017), without a CRE generation permit. The 0.5 MW limit applies to the plant's generating capacity, not to the site's load, and it is expressed in MW rather than in kWp of DC panel.
- Qualified supply. A load with 1 MW or more of demand can register as a Usuario Calificado with CRE and contract with a Suministrador de Servicios Calificados. Demand here means maximum recorded demand in kW over the preceding 12 months, per the SENER acuerdo published in the DOF on 1 March 2017, not annual consumption in MWh.
- An offsite PPA delivered across the network. This is where porteo, the wheeling charge, decides the outcome. CRE revised the porteo estampilla applicable to holders of legacy interconnection contracts in 2020, with the higher charge reported as applying from July 2020. La Jornada reported on 11 June 2020 that CFE Intermediación de Contratos Legados raised those porteo tariffs by 427 to 811% depending on voltage level. Any offsite structure quoted to you should be modeled with the delivered cost, not the generation price.
The rest of the Sonora story, and what is speculation
The Ley Minera reform published in the DOF on 20 April 2022 reserved lithium exploration and exploitation exclusively to the State, eliminated lithium concessions to private parties and assigned the mandate to a new decentralized body. Sonora holds Mexico's most discussed lithium prospects, so any business case that assumed private lithium extraction feeding a Sonora battery supply chain needs rewriting against that statute. The reform passed by simple majority three days after the constitutional electricity reform failed in the Cámara de Diputados on 17 April 2022, and the two are separate instruments.
State-level plans for port expansion, border crossing modernization and new highway capacity have been announced by the Sonora government, and they would help a manufacturer's logistics cost. They do not change the power question, we think, because none of them move electrons. Watch the 400 kV line.
The two signals to watch
Two things. First, a CENACE interconnection result or a PRODESEN transmission program entry that firms up the northwest corridor would pull regional supply relief forward. Second, a reversal of the 2020 porteo revision, or a CRE decision clarifying its application to new contracts rather than legacy ones, would materially improve the economics of offsite renewable supply in the state. Neither is committed. If the transmission schedule slips, the phasing of the plant slips with it, and CFE's announced completion horizon becomes the optimistic case rather than the plan.
Assess your Sonora site before the transmission build lands
Mexico Energy Partners can review a Sonora facility's current CFE tariff class, load profile and interconnection position, and model what onsite generation under 0.5 MW, qualified supply, or an offsite PPA with porteo included would actually cost against present supply. The review needs 12 months of CFE billing, interval data where a meter records it, and the site's single-line diagram.
Request a Sonora facility energy cost review
Related reading: the benefits of utility-scale solar in Mexico, our overview of renewable energy in Mexico, and our utility-scale solar capabilities.