Data centers rely on power for nearly everything. Losing utility power, malfunctioning hardware or an end-of-life replacement can result in thousands or even millions of dollars lost per hour. It’s why backup power is crucial in overall data center design.
What are a data center’s redundant power supplies? These infrastructure units include uninterruptible power supply (UPS) systems, standby generators and power distribution components like switchboards and lines. Because each part is vital in delivering essential power to the data center, having one or multiple duplicates of equipment can maximize availability.
Types of Data Center Power Redundancy
To understand the approaches to data center power redundancy, we need to define N. This variable can designate either the total power needs of the data center (measured in kW) or the number of non-redundant components in the power supply and distribution chain. N is the baseline capacity and means a single point of failure exists in the system.
The most common data center redundancy levels are:
- N+1 redundancy: This configuration indicates an available extra unit can support a component that momentarily needs to be serviced or replaced. N+2, by extension, is less common but provides an additional spare unit.
- 2N redundancy: 2N design keeps an entirely separate system capable of handling all of the data center’s power needs. These will often be two mirrored, identical systems but may also comprise different equipment makes and models. This configuration results in a 100% required capacity and 100% stranded capacity.
- 3N/2 redundancy: The three-makes-two approach offers more reliability than 2N and only strands about 50% capacity, so its operating costs are closer to N+1. To use this configuration effectively, the system must carefully manage the load from the power supplies in use.
- 2(N+1) redundancy: As the highest level obtainable, this configuration uses a completely separate system at the ready to switch in for backup power failure, plus provides additional components should any part in either of the two parallel systems fail.
Note that these same formulas above can serve as data cooling system configurations as well.
How to Choose a Data Center Power Redundancy Configuration
You may assume that having more backup systems is better by default. Instead, the redundancy level you need depends on multiple factors such as:
- Your budget
- Business goals
- IT Environment
- Reliability needs
In critical data center applications like health care facilities where backup power is necessary, redundancy can help mitigate wider-scale disasters from affecting operations. Certain data center certification levels, like the upper classifications of ANSI/TIA-942, require some form of redundancy. According to Uptime Institute, a vast majority of data center managers are seeking higher levels of redundancy than their baseline levels.
The larger your business and data center operations, the more likely you are to invest in a power infrastructure with more resiliency.
Contact DataSpan for Power Redundancy Management
Data center power redundancy is one of many areas of expertise we’ve gained throughout our over 45-year history by serving facilities of all sizes. We can help analyze your data center’s power needs and determine how to configure redundant power supplies for maximum uptime or cost-efficiency.