Data Center Power Distribution: Voltage Drop Best Practices
Engineering ultra-efficient power distribution for data centers where every tenth of a percent voltage drop affects PUE and operational costs.
Data centers represent the most demanding application for voltage drop optimization. With millions of dollars in annual energy costs, even small efficiency improvements translate to significant savings. This guide covers best practices for power distribution design in mission-critical facilities.
Why Data Centers Demand Ultra-Low Voltage Drop
A typical enterprise data center may consume 10-50 MW of power continuously. At this scale, every percentage point of voltage drop represents substantial energy loss. Consider a 20 MW facility: 1% voltage drop equals 200 kW of continuous loss—approximately $140,000 annually at $0.08/kWh.
Beyond direct energy losses, voltage drop affects Power Usage Effectiveness (PUE)—the key efficiency metric for data centers. Lower voltage drop means better PUE, lower operating costs, and often higher facility ratings for sustainability-conscious tenants.
Typical Voltage Drop Budget
Modern data center designs typically target 2% maximum total voltage drop—significantly tighter than the NEC's 5% informational note. This budget is allocated across each segment of the power path:
Design Strategies
- Oversized Bus: Specify busway and switchgear rated significantly above required ampacity to minimize resistance losses.
- Distributed PDUs: Place PDUs close to loads to minimize branch circuit lengths and associated losses.
- Parallel Feeders: Use multiple smaller conductors in parallel rather than single large conductors for easier installation and reduced losses.
- Copper Everywhere: Despite higher cost, copper's lower resistance makes it the standard choice for data center power distribution.
Design Your Critical Power System
Use our voltage drop calculator to verify each segment of your data center power distribution meets its allocated budget.
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