A factory in Mexico should plan for its grid supply to be interrupted. A battery-based uninterruptible power supply (UPS) at medium voltage answers that: it feeds the critical process through its own converter, with 0 ms transfer, so the line keeps running through an outage or a sag.
What the public record says
Mexico’s central bank asked manufacturers with more than 100 workers whether their regular electricity supply had been interrupted in the previous 12 months. In the south, 81.6 percent said yes. In the central region it was 55.0 percent and in the north 49.7 percent. The figures are from Banco de México’s regional survey, as cited in the BBVA Research and AMPIP nearshoring survey of September 2024.
The World Bank’s Enterprise Survey gives a wider sample that includes small firms and services. In its 2023 round, 28.4 percent of firms in Mexico reported electrical outages.
The national grid has run short of reserve. During the May 2024 heat wave the grid operator, CENACE, declared an emergency operating state on May 7 and again on May 9, with blackouts reported in several cities. By May 9 it had issued 11 emergency operating states that year, according to El Financiero.
Single faults also take out whole regions. On September 26, 2025, a transmission line fault during maintenance cut power to about 2 million users across Yucatán, Campeche and Quintana Roo. It began at 14:19, and most of the affected municipalities had power back by 20:30, N+ reported.
Duration is harder to pin down. The state utility’s interruption-duration index for the transmission network rose from 2 minutes in 2018 to 13.5 minutes by the third quarter of 2023, El Imparcial reported from the utility’s own reports. That index averages over every user in the country, so it says little about one industrial feeder. We did not find a published national count of voltage sags at industrial connections, and sags are the events that trip drives. A plant has to take that number from its own power-quality meter.
Why it matters more with nearshoring
New plants are arriving faster than the grid is being reinforced. In the same BBVA Research and AMPIP survey, taken in May 2024, members of the industrial parks association reported 196 new tenants in 2023, 46.3 percent above the 2018 to 2022 annual average, with occupancy at 98 percent. Of those tenants, 27 percent were automotive and 37 percent other manufacturing. Asked what could limit new tenants, 55 percent of respondents named adequate electricity supply, ahead of every other factor. They reported the limits mainly in the north, the northeast and the Bajío, regions where the survey also found the most demand for industrial space.
The cost shows up in lost shifts. In a 2026 survey by the Nuevo León chapter of the export manufacturers’ association Index, 66 percent of participating companies reported outages or frequent intermittency and another 18 percent reported isolated events. Estimated losses ran from one working day, about two shifts, to three or four days at some plants, El CEO reported. The companies described interrupted processes and critical equipment that had to be reprogrammed.
How a medium-voltage UPS protects the line
In a dual-conversion UPS the critical load is always fed through a converter. A grid-side converter draws from the utility, a battery sits behind it, and a load-side converter forms the voltage for the process line. When the grid sags or disappears, nothing switches. The load-side converter keeps forming the voltage from the battery, so the transfer time is 0 ms, within the block’s rating and for as long as the battery reserve lasts.
Battalion builds these blocks at medium voltage, up to 34.5 kV, from 2.5 MW to 5 MW and above per block, with 1 to 4 hours of battery.
The battery then does one of two jobs. Where the plant keeps its generators, it carries the line while they start and take the load. Where it is meant to stand in for the generators, it can do so only if its duration covers the plant’s continuity requirement, which the owner sets from the plant’s own outage history.
Dual conversion or parallel
Battalion builds two configurations on one platform, and its energy management system (EMS) controls both.
| Dual conversion | Parallel | |
|---|---|---|
| Position | In series with the critical load | Beside the load, on the feeder or the plant bus |
| Transfer time | 0 ms at the load | Set by the plant’s own UPS |
| Existing UPS and generators | The UPS can be replaced. Generators only where the battery duration covers the continuity requirement | Kept |
| Choose it when | The process cannot tolerate a sag or a short interruption | The plant keeps its UPS and generators and wants ride-through support, power quality and demand-charge savings |
Parallel leaves the transfer to equipment the plant already owns. A plant with no UPS on its critical line, on a feeder with frequent sags, is a dual-conversion case.
Our EMS already operates batteries in Mexico. The critical power for factories page sets out both configurations, and the medium-voltage UPS page compares them line by line.