# Presentation: 657654

## DC Power for Data Centers –  demonstration summary

**Brian Fortenbery – EPRI Solutions**
**Bill Tschudi – Lawrence Berkeley National Laboratory**

**Sponsored by: **
**California Energy Commission (CEC)****─****Public Interest Energy Research (PIER),**
**California Institute for Energy Efficiency (CIEE).**

**DC Power for Data Centers – **** demonstration summary**

## Overview – Phase 1 

- Background on power
- conversions and their
- efficiencies

- Demonstration objectives

- Configurations

- Industry partners

- Results

- Rationale for the study

## Thomas Edison: 

- “My personal desire would be to prohibit entirely the use of alternating currents.  They are as unnecessary as they are dangerous.  I can therefore see no justification for the introduction of a system which  has no element of permanency and every element of danger to life and property.”

## California Energy Commission

- 10-year initiative focusing on high-tech industries – e.g. data centers
- Help move the market to more efficient technologies
- Research and demonstration projects include technology transfer

**California Energy Commission**
** ****Public Interest Energy Research**
** ****High-tech Buildings Project Objectives**** **

## Why look at Data Centers? 

- Data center power use nationally is large and growing.
- Two prior studies estimated data center energy use:
-    2004  EPRI/Ecos estimated 14.8 TWh
-    2000  Arthur D. Little estimated 10.1 TWh
- 0ne terawatthour = 1,000,000,000 kilowatthours or
- one million megawatthours
**Saving a fraction of this energy is substantial**

## Representative Data Center Power Use

**Representative Data Center Power Use**

- Source: Intel Corp.

- ~50% Power Efficiency

## Power to meet a 100 W Computing Load

**Power to meet a 100 W Computing Load**

- Source: Intel Corp.

**Server fans    ****15W **

**UPS  +PDU ****20W**** **

**PSU ****50W**

- Load 100W

**VR ****20W **

**Room cooling system ****70W**

- Total 275W

- source: Intel Corporation

## DC Demonstration – Timeline

- Stakeholders first met – Fall 2005
- Kick-off meeting – April 2006
- Equipment assembly – May 2006
- Initial “Team Open House” June 7, 2006
- Public Open House events: June 21,
- 	July 12, 26; Aug 9, 16
- End date – August 16,  2006

## Industry Partners Made it Happen

- Alindeska Electrical Contractors
- APC
- Baldwin Technologies
- Cisco Systems
- Cupertino Electric
- Dranetz-BMI
- Emerson Network Power
- Industrial Network Manufacturing (IEM)

- Intel
- Nextek Power Systems
- Pentadyne
- Rosendin Electric
- SatCon Power Systems
- Square D/Schneider Electric
- Sun Microsystems
- UNIVERSAL Electric Corp.

**Equipment and Services Contributors:**

## Other Partners Collaborated

- 380voltsdc.com
- CCG Facility Integration
- Cingular Wireless
- Dupont Fabros
- EDG2, Inc.
- EYP Mission Critical
- Gannett
- Hewlett Packard

- Morrison Hershfield Corporation
- NTT Facilities
- RTKL
- SBC Global
- TDI Power
- Verizon Wireless

**Stakeholders:**

## Data Center Power Use 

- Data center power use nationally is large and growing.
- Two studies estimated data center energy use:
- 	2004  EPRI/Ecos estimated 14.8 TWh
-  	2000  Arthur D. Little estimated 10.1 TWh
- 0ne terawatthour = 1,000,000,000 kilowatthours or
- one million megawatthours
-  **Saving a fraction of this energy is substantial**

## This demonstration focused on reducing power delivery and conversion losses observed in our prior work:

***Uninterruptible Power Supplies (UPS)***

***Power Supplies in IT equipment***

## UPS and Power Supply efficiency 

**We observed a wide range of performance from the worst to the best**
**Our original goal was to move the market to the higher performing systems**
**Incentive programs, labeling, education programs were all options – and still are**

## Data Center Power Delivery System

**Data Center Power Delivery System**

**Power Dist**
**98 - 99%**

**UPS**
**88 - 92%**

**Power Supply**
**68 - 72%**

**DC/DC**
**78 - 85%**

**The heat generated from the losses at each step of power conversion requires additional cooling power **

**HVAC: Power for cooling can equal or exceed the direct losses**

**Notes:**
The electrical power to IT equipment flows through this inefficient delivery path

## The questions we were addressing:

- 	**Could some of the conversion steps be eliminated to improve efficiency?  Could a demonstration be devised to measure actual savings?**

## DC Demonstration - Objectives

- DC powered server equipment exists in the same form factor or can readily be built from existing components
- DC powered server equipment can provide the same level of functionality and computing performance when compared to similarly configured and operating AC server equipment
- Efficiency gains from the elimination of multiple conversion steps can be measured by comparing  traditional AC delivery to a DC system
- DC system reliability could be as good or better than AC system reliability

**The demonstration’s original objectives were to show a rack level solution:**

## The project team soon defined additional objectives:

- Demonstration of 380 V. DC distribution at the facility level compared to conventional AC systems
- Demonstration of other DC solutions (48 volt systems)
- Evaluation of safety considerations
- Demonstrate ability to connect alternative energy solutions (PV, fuel cells, etc.)

## What the demonstration included 

- Side-by-side comparison of traditional AC system with new DC system
-  Facility level distribution
-  Rack level distribution
- Power measurements at conversion points
- Servers modified to accept 380 V. DC
- Artificial loads to more fully simulate data center

## Additional items included 

- Racks distributing 48 volts  to illustrate that other DC solutions are available, however no energy monitoring was provided for this configuration
- DC lighting was included!

## Typical AC Distribution Today

## Facility-Level DC Distribution

- 380V.DC

## Rack-Level DC Distribution

## Demonstration Layout

**Demonstration Layout**

## Details

- Safety was reviewed by a committee of the partners.  No significant issues were identified.  Only concern was whether fault currents would be large enough to trip protective devices. Final report will address safety and applicable codes and standards
- All distribution equipment is UL rated for DC applications

-      	No standard connector has been agreed upon for the server 	DC connection
-  	With widespread adoption, reliability should be improved – 	fewer potential points of failure. 	Eliminating heat sources 	should help.

## Measured Results

- Facility level overall efficiency improvement:
- 	 10 to 20%
- Smaller rack level overall efficiency improvement but other benefits include:
- 	Thermal benefits
- Smaller power supply in server
-  Transition strategy for existing centers

##  AC system loss compared to DC

- 9% measured improvement

- 2-5% measured improvement

##  Implications could be even better for a typical data center

- Redundant UPS and server power supplies operate at reduced efficiency
- Cooling loads would be reduced.
- Both UPS systems used in the AC base case  were “best in class” sytems and performed better than benchmarked systems – efficiency gains compared to typical systems could be higher.
- Further optimization of conversion devices/voltages is possible

## Data Center Power Delivery System

**Data Center Power Delivery System**

**XFMR**
**98% - NA**

**UPS**
**87 - 92%**

**Power Supply**
**90 - 92%**

**Notes:**
The electrical power to IT equipment flows through this inefficient delivery path

## Data Center Power Delivery System

**Data Center Power Delivery System**

**Power Dist**
**98% - NA**

**UPS**
**85 - 92%**

**Power Supply**
**73 - 92%**

**Notes:**
The electrical power to IT equipment flows through this inefficient delivery path

## Results

**Results**

- What does 15% increase in efficiency mean
-  to the electrical power grid?

## DC Power - next steps:

-  DC power pilot installation(s)
-  Standardize distribution voltage
-  Standardize DC connector and power strip design
-  Server manufacturers develop power supply 	specifications
-  Power supply manufacturers develop prototypes
-  UL and communications certification
-  Address other types of IT equipment (storage,  	switches, etc.)

## Follow progress on DC power in data centers on-line

- Lawrence Berkeley National Laboratory
- 	websites for more information
- http://hightech.lbl.gov/
- http://hightech.lbl.gov/dc-powering/

## Additional Information

**Project Coordination & Contacts:**
**Lawrence Berkeley National Laboratory**
-  Bill Tschudi, Principal Investigator
- 	_[wftschudi@lbl.gov](mailto:wftschudi@lbl.gov)_
**Ecos Consulting**
- My Ton
- 	 _[mton@ecosconsulting.com](mailto:mton@ecosconsulting.com)_
**EPRI Solutions**
- Brian Fortenbery
- 	_[bfortenbery@eprisolutions.com](mailto:bfortenbery@eprisolutions.com)_