Wired for Change: Data Centers' Dynamic Shift to Hybrid Power Solutions

Overview

The starting point is UPS stored energy, which typically bridges 30 minutes to over 2 hours until gensets or the grid restore supply. The paper positions the UPS as a bidirectional energy resource and eventually an energy management controller. The roadmap has three stages: today, SOFCs or turbines on natural gas for prime power and BESS on the AC bus to cut genset starts; in the near future, BESS as a long-duration DC source to the UPS once high-voltage batteries are supported; long term, PEM fuel cells replace diesel and natural-gas SOFCs are retrofitted to hydrogen.

The phase split is explicit: Phase 2 replaces diesel with backup PEM fuel cells, Phase 3 uses SOFC as prime power with the grid as backup. Integration decisions include whether the fuel cell connects through a standalone DC-to-AC converter or directly on DC to the UPS. For spiky loads, dedicated single-ended substations with N+1 BESS blocks are suggested instead of spreading instability across all blocks, and raising the energy-storage voltage is listed as a way to extend battery backup time in outages.

On safety, hydrogen fuel-cell rooms need leak detection, ventilation, air recirculation and flame detection, while SOFCs can run on biogas or natural gas. The paper also addresses common misconceptions about fuel-cell safety and cost. It is a vendor roadmap with no published numerical comparison and it centres its own solution portfolio, so it is best read as a framework of architecture options.

Key points

1. UPS stored energy typically bridges 30 minutes to over 2 hours until gensets or the grid restore supply.
2. Roadmap: today SOFCs or turbines on natural gas for prime power and BESS on the AC bus to cut genset starts; near future BESS as long-duration DC source to the UPS; long term PEM fuel cells replace diesel and NG SOFCs go to hydrogen.
3. Spiky loads can go to dedicated single-ended substations with N+1 BESS blocks rather than spreading instability across all blocks.
4. Fuel-cell integration options: a standalone DC-to-AC converter or direct DC connection of the fuel cell to the UPS.
5. Phase 2 replaces diesel with backup PEM fuel cells; Phase 3 uses SOFC as prime power with the grid as backup.
6. Hydrogen fuel-cell rooms need leak detection, ventilation, air recirculation and flame detection; SOFCs can run on biogas or natural gas.
7. Raising energy-storage voltage is listed as a way to extend battery backup time during outages.

Using it in design

• Extend the power-source library beyond utility plus diesel: BESS (AC- or DC-coupled to the UPS), SOFC prime power, PEM backup fuel cell, PV and CHP, each with fuel type, start time, ramp capability and emissions factor.
• Allow grid-as-backup topologies.
• When hydrogen storage or fuel cells are placed, require ventilation, H2 leak detection and flame detection, and warn when a dedicated BESS block for spiky AI loads lacks N+1.
• Report Scope 1 emissions by source.

Who should read it

Electrical designers and strategists evaluating non-diesel backup and prime-power architectures for grid-constrained sites.

Related standards

• IEC 62282-3-100
• NFPA 2
• NFPA 855
• IEEE 1547

Publication details

Authors

Vertiv

Publisher

Vertiv

Year

2024

Document number

SL-71292

Document language

English

Source type

Manufacturer

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation