Conclusion

The basic configuration of UPS power-backup systems at data centers should be updated to include an EVR or automatic voltage regulator as a standard component.

  • By separating the power-conditioning function from the power-backup function, an EVR-protected UPS system can achieve the electrical efficiency promised by manufacturers of eco-mode-enabled UPS systems while simultaneously and significantly reducing the risk of UPS-caused outages. Although EVRs are a relatively new technology, their simple design and established record of reliability should allow facility managers to welcome their introduction.
  • The savings over the 10-year lifespan of the UPS system at a typical data center more than justify the additional initial costs of an EVR equipped with a static switch.
  • For a 500kVA facility, savings will total at least $371,000 over 10 years—and that number will scale directly relative to facility size.
  • Beyond these easily calculable savings, including an EVR in the basic backup-power and power-management system design at data centers has the potential to alter the risk formulas used to determine levels of redundancy required at the UPS and data center levels. If this proves true, adoption of this design could dramatically reduce infrastructure costs.