Medium-Voltage UPS for Data Centers
ON.energy’s medium-voltage UPS protects AI data centers from power disturbances and shields the grid or onsite generation from AI load swings. Currently deploying at gigawatt scale, ON’s MV UPS is proven to meet emerging large-load voltage ride-through requirements.
Consult the DatasheetAI UPS Frequently Asked Questions
An MV UPS acts as an electrical firewall by continuously decoupling the facility load from the grid. In ON.energy’s inline, double-conversion architecture, power passes through a DC link and controlled power converters; integrated energy storage supplies or absorbs transient energy. Grid disturbances remain upstream, while rapid AI load changes remain downstream.
Faults, sags and swells stop at the UPS input. Because all power is continuously converted through a DC link, the load never sees the disturbance and there is no transfer event. Integrated energy storage carries the facility through outages for 1 to 8+ hours, depending on configuration, with zero transfer time.
AI workloads can swing power by ±70% of interconnection capacity within milliseconds. Placing integrated energy storage between the facility and the grid absorbs those swings, with less than 1% battery state of charge variation, and presents a smooth, ramp-rate compliant profile to the grid regardless of what the GPUs are doing.
Voltage ride-through is the ability to stay connected and keep operating through grid voltage disturbances instead of tripping offline and risking cascading failures. Large-load rules such as ERCOT’s LLVRT standards are making it a requirement. AI UPS™ rides through 0 V for the duration of the BESS (1+ hour) and sustains 120% voltage for 12 seconds.
A hall-level UPS protects one room from inside the building, so the campus still looks like a large, volatile load to the grid. A site-boundary UPS sits upstream at medium voltage, where the site meets the grid, decoupling the whole facility and handling grid compliance in one place. It is outdoor rated (IP55) and scales in 3.5 MW lineups to multi-GW sites.
Talk with our engineering and sales teams to go over specs, ride-through performance, and your data center’s power architecture and interconnection plan. and we’ll connect you with a team member.
01 — EXECUTIVE SUMMARY
The AI / Grid Paradox
As data center workloads shift toward AI and HPC, operators face a dual challenge: protecting sensitive, volatile compute loads from grid disturbances while ensuring the facility itself does not destabilize the local grid.
AI UPS™ solves this paradox — decoupling the load from the grid so that massive compute transients never disrupt the grid, and grid faults never disrupt the compute.
02 — THE CHALLENGE
Converging Power Requirements
Rapid Load Transients
GPU clusters ramp from idle to full load in milliseconds, creating power swings beyond traditional system tolerance.
Zero Tolerance for Interruption
Training runs worth millions in compute time can be lost to momentary power disturbances.
Unprecedented Scale
Giga-campus deployments demand multi-GW power systems that break the traditional low-voltage UPS architecture mold.
Voltage Ride-Through
Facilities must remain connected during grid disturbances rather than disconnecting and causing cascading failures.
Frequency Ride-Through
Similar requirements apply during frequency excursions across both 50 Hz and 60 Hz systems.
Ramp Rate Control
Large loads cannot appear or disappear instantaneously from the grid's perspective.
Traditional Approaches Fall Short
Conventional architectures rely on low-voltage UPS systems without grid-interactive capabilities, static transfer switches with non-zero transfer times, generators with seconds-long startup delays, and separate battery storage that doesn't provide UPS functionality. This fragmented approach creates protection gaps, compliance challenges, and missed economic opportunities.
03 — AI UPS™ SOLUTION
Unified Power Protection
and Grid Integration
AI UPS™ delivers a comprehensive solution through a single integrated system — continuously conditioning all power flowing to the facility while presenting a compliant profile to the grid.
| Capability | Performance |
|---|---|
| Transfer Time | Zero (continuous power conversion) |
| Power Quality | Complete isolation from grid disturbances |
| Backup Duration | 1–8+ hours (configurable) |
| Scalability | 3.5 MW per lineup to multi-GW per site |
| Redundancy | N+1 to 2N+1 configurations |
| Installation | Outdoor-rated (IP55), upstream of facility |
04 — FULL-SCALE VALIDATION
Proven at the National
Laboratory of the Rockies
AI UPS™ has been validated at full scale through the ARIES (Advanced Research on Integrated Energy Systems) platform - a world-class research infrastructure operated by the National Laboratory of the Rockies at its Flatirons Campus in Colorado.
The ARIES Flatirons Campus provides hardware-in-the-loop testing at up to 20 MW with voltage levels reaching 13.2 kV - representing the real-world distribution and bulk power system interface. The facility offers two controllable grid interfaces: a 7 MW grid simulator that replicates utility grid behavior including disturbances and voltage ride-through events, and a 20 MW load simulator with 400-microsecond response times that reproduces real-world demand dynamics. AI UPS™ connects at medium voltage to both interfaces.
This enables ON.energy to prove AI UPS™ transient response and load smoothing performance under the most demanding conditions — including voltage ride-through events, frequency excursions, and rapid load transients — under controlled, repeatable conditions with GPS-synchronized medium-voltage data acquisition at every node.
Why This Matters
Unlike lab-scale demonstrations, the Flatirons Campus tests AI UPS™ at the actual voltages, power levels, and grid conditions it will face in production deployments. ON.energy is running a full 3.2 MW branch through the most stringent load profiles in the industry, proving transient response and load smoothing performance at scale. The facility's digital real-time simulators - the largest in any R&D environment - scale test results to represent community and regional grid configurations, validating performance across every scenario before a single unit ships to a customer site.
05 — GRID COMPLIANCE
Voltage & Frequency
Ride-Through
AI UPS™ meets and exceeds the most stringent ride-through requirements currently proposed or in effect, including ERCOT's Large Load Voltage Ride-Through (LLVRT) standards.
AI UPS™ (MV UPS)
AI UPS™ dramatically exceeds ERCOT compliance - riding through 0V continuously for the duration of the BESS (1+ hour), and sustaining 120% voltage for 12 seconds.
LV UPS (Competitor)
Traditional low-voltage UPS systems fail to meet ERCOT's Large Load ride-through requirements - leaving critical areas of non-compliance at low voltages.
PROVEN VRT PERFORMANCE
Real data from our NLR full-scale testbed
During a voltage ride-through event, the grid voltage drops to zero (true ZVRT event) while the AI UPS™ maintains perfectly stable load voltage at ~1.06 p.u. throughout. 10 ms timestep. Drag to zoom, double-click to reset.
Grid Voltage on graph doesn't drop to 0 due to location of the meter at Medium Voltage.
06 — TRANSIENT MANAGEMENT
AI Workload Transient
Management
Modern AI workloads create power swings of ±70% of interconnection capacity within milliseconds. AI UPS™ completely decouples the facility's internal load behavior from its grid-facing power profile.
Absorb
Rapid load changes absorbed using integrated energy storage with minimal (<1%) battery state of charge variation.
Smooth
Presents a smooth, predictable power profile to the grid regardless of internal workload behavior.
Comply
Maintains ramp rate compliance automatically, protecting grid infrastructure from stress.
PROVEN TRANSIENT MANAGEMENT
Real data from our NLR full-scale testbed
During rapid AI workload transients, the AI UPS™ absorbs load power swings using integrated energy storage, presenting a smooth grid-facing power profile. 10 ms timestep. Drag to zoom, double-click to reset.
Ready to Transform Your Power Architecture with AI UPS™?
For technical inquiries, system sizing, or project discussions, our engineering team is ready to design a solution for your facility.
07 — SYSTEM ARCHITECTURE
Modular Design
at Any Scale
Each data hall receives an independent AI UPS™ system with built-in redundancy - ensuring fault isolation, independent maintenance, and scalable deployment.
N+1 to 2N+1
| Specification | Value |
|---|---|
| Environmental Rating | IP55 (outdoor rated) |
| Installation Location | Upstream of facility switchgear |
| Design | Compact modular |
| Cooling | Self-contained, no building integration |
| Maintenance | Full access from grade level |
| Base Module | 3.5 MW lineup |
| Site Scalability | Unlimited - multi-GW supported |
| Backup Duration | 1–8+ hours per configuration |
08 — ECONOMIC VALUE
Beyond Backup:
Grid Services Revenue
AI UPS™ transforms what is traditionally a cost center into a revenue generator through participation in grid services.
Peak Shaving
Reduce facility demand charges by limiting grid draw during peak periods. Store low-cost energy during off-peak hours.
Demand Response
Participate in utility demand response programs and provide grid support during system emergencies.
Energy Arbitrage
Charge during low-price periods, discharge during high-price periods. Particularly valuable in ERCOT and CAISO markets.
Ancillary Services
Frequency regulation, spinning reserves, and voltage support across multiple market structures.
Total Cost of Ownership
| Factor | Traditional UPS + BESS | AI UPS™ |
|---|---|---|
| GPU Ripple | Buffering with ms delay | 100% filtering |
| Transfer Time | 10–20 ms (STS) | Zero |
| Grid Compliance | Requires additional equipment | Integrated |
| Revenue Generation | Limited (BESS only) | Multiple streams |
| Scalability | Limited by LV architecture | Linear to multi-GW |
| Maintenance | Separate UPS & BESS systems | Single integrated system |
| Space Requirements | Indoor UPS + outdoor BESS | Outdoor only |
09 — COMPLIANCE & STANDARDS
Industry Standards
Compliance
Grid Interconnection
- IEEE 1547 - Distributed Energy Resources
- ERCOT NOGRR282 - Large Load Requirements
- PJM, CAISO, MISO regional requirements
Data Center
- Uptime Institute Tier III/IV
- TIA-942 Infrastructure Standards
- ASHRAE TC 9.9 Environmental Guidelines
- IEC 62040-3 Class 1 UPS Performance
Electrical Safety
- UL 1741 - Inverters & Interconnection
- UL 9540 - Energy Storage Systems Safety
- IEEE 1584 - Arc-Flash Hazard
- NFPA 70 - National Electrical Code
10 — ABOUT ON.energy
Proven Technology
Foundation
ON.energy builds and operates hyperscale power systems to solve the toughest resilience challenges. AI UPS™ is built on grid-scale power conversion and energy storage technology deployed in the hundreds of gigawatts worldwide.