1. technology and computing
2. data centers

PAR4® IT Energy Efficiency Rating and Certification
PAR
4®
A comprehensive metric for IT energy efficiency tested by
Underwriters Laboratories (UL) to comply with UL standard UL2640
The PAR4 measurement and rating gives you the accuracy
needed to uncover hidden capacity in your data center.
Power Assure rated many servers and found that nameplate
power consumption figures are almost always overstated.
Even worse, in some cases they are understated. Either
way, it is very difficult to plan your power delivery capacity
optimally without knowing how much power your servers
actually consume.
Power Assure’s PAR4 rating measures servers under maximum
and no-load conditions to certify and rate IT equipment
accurately, as well as provide a rating system to compare
efficiency across multiple generations of IT equipment.
The PAR4 methodology reports four measurements of your
equipment’s power consumption: when the equipment is off,
idle, loaded and at peak. The PAR4 value is the transactions
per second per watt (Tps/W) at 100% load. The PAR4 numbers
can then be used for accurately planning the maximum power
allocation.
To simplify comparisons, a PAR4 rating system which is based
on Moore’s Law, labels comparative efficiency for each year past, present and future. This allows us to classify equipment
on its energy efficiency relative to past and future equipment.
• A larger PAR4 value means
higher energy efficiency.
• Every 100-point increase
in PAR4 indicates
a doubling of efficiency.
Make Better Informed Decisions
Example: A server with PAR4 value of 1750 is
Green in 2007 and becomes Gold in 2009.
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ENERGY EFFICIENCY
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PAR
certified
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PAR
certified
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PAR
certified
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ENERGY EFFICIENCY
2011
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BLACK
2011
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ENERGY EFFICIENCY
SILVER
2011
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• There are four energy
efficiency rating levels:
Green (most efficient),
Gold (very efficient),
Silver (fairly efficient),
Black (least efficient).
GOLD
®
GREEN
2011
Provisioning new servers is typically done by performance
indicators based on processing capacity expressed in
transactions per second. While performance ratings
based on transactions per second are important, the
energy consumption can differ significantly between
equipment with similar performance characteristics and
capabilities. Additionally, given Moore’s Law, IT equipment
performance doubles every two years, making it even
harder to compare performance and energy efficiencies
between different generations of IT equipment.
®
Faced with skyrocketing demand for new applications, data
centers are running out of power, even when the racks or
rooms are half-full. Data centers are typically provisioned
based on the power consumption figures provided on the
nameplates or by the vendor. Unfortunately these figures are
designed to be conservative and are therefore overstated,
providing a wide margin of error. This leaves much-needed
power stranded on the power lines rather than being put to
productive use in your data center. To make matters worse,
by planning on higher power consumption it is likely that you
are over-cooling your data center.
The UL and Power Assure
Solution: PAR 4 Rating
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PAR
certified
Uncover Hidden Capacity
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ENERGY EFFICIENCY
Teamed with UL for PAR4
Certification
To make it easy and ubiquitous for hardware vendors to
publish accurate power consumption figures, UL, the leader
in compliance testing solutions, teamed up with Power
Assure to provide equipment manufacturers with PAR4
energy performance testing and certification as part of UL’s
standard product certification process. With PAR4 included,
UL provides a standard for data center managers to assess
their IT equipment energy efficiency for accurate capacity
planning as well as for ongoing hardware refresh programs.
Free Up Stranded Power
Having accurate IT equipment power consumption figures not
only helps in planning new builds, but allows you to uncover
“hidden” capacity in your data center. PAR4 measurements
can be summed to calculate the maximum peak load of
IT equipment in a rack, or an entire data center. If you are
underutilizing the power brought to each rack, chances are
you are leaving a lot of power “on the table,” unused because
it was previously hidden by faulty specifications. By reallocating power based on actual consumption, data center
operators can often double the compute capacity of their
data center.
Easy to Start, Simple to Maintain
Stranded Power
Power
To uncover stranded power and hidden capacity, the
process starts with accurate measurements. By taking
advantage of Power Assure’s Capacity Assessment service,
data center managers see true power usage versus
perceived power consumption.
After completing the assessment and providing
recommendations, Power Assure can provide an on-going
real-time management service that allows you to implement
your plans effectively and achieve your service needs.
Hidden Capacity
Time
Specification Max
Actual Capacity Max (PAR4)
Actual Peak
POWER ASSURE’S CAPACITY
ASSESSMENT SERVICE
• Measures current capacity and usage
• Performs PAR4 measurements
• Analyzes how much power is wasted
• Provides recommendations for technology
refreshes and for associated space and power
savings
Actual Average
Actual Usage
Idle
About Power Assure
Headquartered in Santa Clara, CA, Power Assure is a
leading developer of Data Center Infrastructure and Energy
Management software for large enterprises, government
agencies, and managed service providers. Power Assure’s
award-winning solutions provide visibility, intelligence,
analytics and automation to help CIOs, IT directors, and
facilities managers optimize capacity, service levels, and
power consumption within and across data centers. Power
Assure’s partners include ABB, Cisco, Dell, Dominion Energy,
IBM, In-Q-Tel, Raritan, UL and VMware.
Ready to achieve the best performance from your data center?
CALL US or VISIT OUR WEBSITE
Phone: +1.888.225.1575
www.powerassure.com
© 2011 Power Assure, Incorporated. All rights reserved.
PAR4 and Power Assure are registered trademarks of Power Assure, Inc. – Patents Pending.
EM/4™ is a trademark of Power Assure, Inc. V120305
UL is a registered trademark of Underwriters Laboratories
POWER ASSURE, INC.