# Presentation: 248966

## Data Center Energy Use, Metrics and Rating Systems

**Steve Greenberg**
**Energy Management Engineer**
**Environmental Energy Technologies Division**
**Lawrence Berkeley National Laboratory**
**October 31, 2007**

## Today’s Agenda

**Introduction**
**Energy Usage in Data Centers**
**Opportunities for Improvement**
**Selecting a Performance Metric**
**Rating Systems**
**Implementing a Metric**
**Next Steps**

## The Data Center Challenge

**Data Centers 15-40x the energy intensity of typical office buildings **
**A single rack of servers can be 20 kW **
**$17k per year (at $.10/kWh) *****per rack***
**Hundreds of racks per center**
**Where are the opportunities?**
**25 data centers benchmarked**

## Typical Data Center Design

## Data Center Metrics

**High-level **
**IT/total **
**useful work/total **
**Subsystem**
**Power distribution **
**HVAC**
**Lighting**
**Facility performance (other than energy)**

## High-level Facility Metrics

- Source: The Green Grid Data Center Power Efficiency Metrics. ©2007. Used with permission

- E.g. Green Grid, PUE and DCiE

## High-level Facility Metrics

**E.g. Uptime Institute: **
**	****“****Site Infrastructure Power Overhead Multiplier (SI-POM)” = Total/IT**

- Source: “Four Metrics Define Data Center “Greenness” “,
- Uptime Institute, 2007.

## Percentage of electricity delivered to IT equipment

**Average .57**

- Higher is better

- Source:  LBNL Benchmarking

## Total Power/IT Power

**Average 1.83**

- Lower is better

- Source:  LBNL Benchmarking

**Total Power/IT Power**

## Other Data Center Metrics

**Watts per square foot**
**Power distribution: UPS efficiency, IT power supply efficiency**
**Uptime: IT Hardware Power Overhead Multiplier (ITac/ITdc)**
**HVAC**
**IT total/HVAC total**
**Fan watts/cfm**
**Pump watts/gpm**
**Chiller plant (or chiller or overall HVAC) kW/ton**
**Lighting watts/square foot**
**ANCIS: Rack cooling index (fraction of IT within recommended temperature range)**
**ANCIS: Return temperature index (RAT-SAT)/IT****Δ****T**

## IT equipment load density

## HVAC system effectiveness

- We observed a wide variation in HVAC performance

## Efficiency of  Information Technology Power Supplies and Uninterruptible Power Supplies

**	**

- Power supplies in IT equipment generate much of the heat.  Highly efficient supplies can reduce IT equipment load by 15% or more.

- UPS efficiency also varies a lot.
- (Do they need the same environment as the IT equipment or can their conditions be relaxed?)

## Summary of Opportunities for Energy Efficiency

** ****Air management**
** ****Right-sizing**
** ****Central plant optimization**
** ****Efficient air handling**
** ****Free cooling**
** ****Humidity control**
** ****UPSs and power supplies**
** ****On-site generation**
** ****Liquid cooling**
** ****Design and M&O processes**

## Benchmarking for Energy Performance Improvement

**	****Energy benchmarking can be effective in helping to identify better performing designs and strategies.  As new strategies are implemented (e.g. liquid cooling), energy benchmarking will enable comparison of performance.**

## Rating Systems for Energy Efficient Data Centers

**Options:**
**Rating system for new data centers based on design criteria**
** ****Recognition program for upper quartile energy efficient performance for existing data centers**
**Performance label for existing data centers, with requirement for continuous improvement**

## Rating system based on design criteria

**Model: LEED-New Construction**
**Labs21 developed a LEED-based rating system for laboratories – basis for proposed LEED for Labs**
**LBNL is working with the California Energy Commission on creating credits for data centers**
**Principle focus on energy efficiency**
**Secondary focus on site, materials, water, indoor environment**
**Must achieve a minimum number of points to be certified**
**Documentation required for each point**
**Additional levels of achievement possible**
**Does not address post-construction performance**

## Recognition program for energy efficient performance 

**Model: ENERGY STAR for Buildings**
**Would need statistical model for existing data centers that included process as well as building performance**
**Exclusive focus on energy efficiency**
**Performance rating of ****≥75 points on a scale of 1-100 based on statistical data**
**Application requires**** **
**Company to benchmark itself against performance index**
**Professional engineer verifies and prepares statement of performance**
**Label is good for one year**
**Reapplication required to maintain ENERGY STAR**

## Performance label for continuous improvement

**Model: Facility certification for energy efficiency **
**Under development for industrial plants- 2009 pilot**
**Model suitable for existing data centers**
**Comprehensive for processes and building**
**Exclusive focus on energy efficiency**
**Certification requires:**
**Compliance with energy management standard**
**Minimum implementation of recommendations that meet company IRR**
**5% energy intensity reduction over 2 years**
**Verification of energy savings required**
**Re-certification every 3 years; 7.5% energy intensity reduction requirement**