Data Center Storage Key Product Criteria

ENERGY STAR certified data center storage products must use efficient power supplies and variable speed fans if using active cooling, make available storage management features, report on energy consumption under different operating conditions. Below we provide an overview of the key criteria for the power supply in Table 1 and Table 2.¹

Table 1: Power Supply Efficiency Requirements
PSU Type	Rated Output Power	20% Load	50% Load	100% Load
Redundant and Non-Redundant Capable PSU	All Output Levels	85%	89%	85%

Table 2: Power Supply Power Factor Requirements
PSU Type	Rated Output Power	20% Load	50% Load	100% Load
Redundant and Non-Redundant Capable PSU	All Output Levels	0.80	0.90	0.95

In Table 3 below we describe the capacity optimizing methods (COMs) that are required to be made available. In Table 4 is a list of the number of COMs required to be made available based on different types of storage products.

Table 3: Recognized Capacity Optimizing Methods (COMs)
Thin Provisioning allocates the physical capacity of a volume or file system as applications write data, rather than allocating all the physical capacity at the time of provisioning.
Data Deduplication replaces multiple copies of data — at variable levels of granularity — with references to a shared copy in order to save storage space and/or bandwidth.
Lossless Compression encodes data to reduce size and preserves the entire content of the original data (from which the original data can be reconstructed exactly).
Delta Snapshots are a type of point-in-time copy that preserves the state of data at an instant in time by storing only those blocks different from an already existing full copy of the data.

Table 4: Minimum Number of COMs
SNIA Storage Product Category²	Minimum number of COMs required to be made available
Online 2	0
Online 3	1
Online 4	1

¹See Section 3 (Qualification Criteria)of the ENERGY STAR Data Center Storage specification
²The ENERGY STAR storage taxonomy is consistent with the taxonomy developed by the Storage Networking Industry Association Green Storage Initiative as defined in "SNIA Emerald™ Power Efficiency Measurement Specification" Version 2.0.0 rev 1, 12 December, 2012. Further detail may be found at www.snia.org/green.