# Presentation: 907365

## Reliability and Energy Efficiency – Not Mutually Exclusive 

- William Tschudi
- Principal Investigator
- Lawrence Berkeley National Laboratory

## Acknowledgements

- California Energy Commission
- Pacific Gas and Electric Company
- Uptime Institute
- Critical Facilities Roundtable
- Rumsey Engineers
- RMI
- E Source
- Power Supply Manufacturers Association
- Industry Partners (Too many to name all)
- Subcontractors:
- 	EYP Mission Critical Facilities, Ecos Consulting, EPRI-PEAC

## Energy Intensive High-tech Buildings

## We Also Operate Data Centers

## Why Research Data Centers?

- Overview

- Utilities were receiving requests for unrealistic power densities
- A lot of misinformation was (is?) circulating
- Large continually operating base loads
- We saw large energy efficiency opportunities in other High-Tech buildings
- Technology improvements are transferable to other building types

## Prior Data Center Research

- Research “roadmap” for the CA Energy Commission
- Participation in design charrette organized by Rocky Mountain Institute
- Energy benchmarking and case studies for 14 data centers
- Market assessment in CA

- Overview

## Current Data Center Research Activities

- Benchmarking and Best Practices
- Investigate UPS Efficiency 	Improvement
- Investigate Power SupplyImprovement
- Develop performance metrics – computing horsepower and 	energy use
- Demonstration Projects
- Technology Transfer

## Energy Benchmarking

- Benchmarking

- Benchmark (measure) energy use in 6-10 additional data centers
- Energy intensity and end-use
- System and component efficiency
- Efficiency improvement suggestions
- Solicit additional benchmarks from other sources
- Identify and analyze better performing systems and document in “Best Practices” summary
- Develop self-benchmarking protocol

## Electricity Flows In Data Centers

- local distribution lines

- to the building, 480 V

- HVAC system

- lights, office space, etc.

- UPS

- PDU

- computer racks

- backup generators

- computer
- equipment

- uninterruptible
- load

- Electricity Flows In Data Centers

## IT Equipment Loading

- Both LBNL and Uptime Institute found average IT equipment loading at
- ~25 W/ft2

- Benchmarking

## Projecting IT Load When Fully Loaded

- Benchmarking

## Data Center Benchmarking

- Benchmarking

## Chiller Comparison

- Average 0.75

- Benchmarking

## Total Chilled Water System Efficiency

- Average 1.69

- Benchmarking

## UPS System Benchmarking

- Benchmarking

## Standby Generation Loss

- Several load sources
- Heaters
- Battery chargers
- Transfer switches
- Fuel management systems
- Heaters alone (many operating hours) use more electricity than ever produced by the generator (few operating hours)
- Opportunity may be to reduce or eliminate heating, batteries, and chargers

- Benchmarking

## Standby Generator Heater

## No Impact on Reliability

- Benchmarking

- Chiller and pumping efficiency
- Use of lighting controls
- Variable speed drives – pumps, chillers, fans
- Free cooling
- Improved  UPS efficiency

## Improved Reliability and Energy Performance

- Benchmarking

- Better match systems to their loads
- Improve humidity control and eliminate CRAC unit fighting
- Water side economizers
- Better control strategies – setpoints, cooling tower staging
- Better thermal stratification – high ceilings and properly sized underfloor
- Air management – delivering air where it’s needed

## General Recommendations

- Benchmarking

- Benchmark to know where you stand
- Life-cycle cost analysis
- Facilities partnership with IT professionals
- Evaluate load spreading vs. compaction

## Available Benchmark Data?

- Benchmarking

- Sources of other benchmark data?
- Please contact LBNL:
-  Steve Greenberg: segreenberg@lbl.gov
-  Bill Tschudi: wftschudi@lbl.gov

## Future Direction

- Benchmarking

- Develop consensus on performance benchmarks, collect data, quantify energy savings potential
- Incorporate other industry benchmark data

## Data Center Power Delivery

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

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

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

**dc/dc**
**78 - 85%**

**HVAC**
**1,200W / 1 Ton (76%)**

**US Annual Energy Consumption of 30TW-h flows through this inefficient delivery path**

## Cost of Power Delivery

| Power Path Efficiency |  | Power (kW) | MW-h | Cost |
| --- | --- | --- | --- | --- |
|  | Load Cooling | 3.1 | 113 | $8,500 |
| Loads  | Systems (x100)
(not including dc/dc & ac/dc) | 9.8 |  |  |
| x 85% | Dc/dc | 2.1 | 109 | $8,200 |
| x 70% | Power supply | 5.1 |  |  |
| x 90% | UPS | 1.9 |  |  |
| x 98% | Distribution | 0.4 |  |  |
| x 76% | Delivery Cooling | 3.0 |  |  |
| Total = 40% | Total |  | 222 | $16,700 |

**Total efficiency ****≈ 40%****Cost of power delivery = $8,200 / 100**

- Source: EPRI PEAC

## Improvements in Cost of Power Delivery

| Power Path Efficiency |  | Power (kW) | MW-h | Cost ($k) |
| --- | --- | --- | --- | --- |
|  | Load cooling | 3.1 | 113 | 8.5 |
| Loads  | Systems (x100) 
(not including dc/dc & ac/dc) | 9.8 |  |  |
| x 85% | Dc/dc | 2.1 | 109  62 | 8.2  4.7 |
| x 70%  85% | Power supply | 5.1  2.1 |  |  |
| x 90%  94%  | UPS | 1.9  0.9 |  |  |
| x 98% | Distribution | 0.4  0.3 |  |  |
| x 76% | Delivery Cooling | 3.0  1.7 |  |  |
| Total = 40%  51% | Total |  | 222  175 | 16.7  13.2 |

**Annual cost reduced by $3,500 / 100**

- Source: EPRI PEAC

## UPS Activities

- UPS Systems

- Determine the range of current UPS efficiencies, highlight more efficient designs, and provide a means for comparing their total cost of ownership (TCO).
- Propose a new UPS labeling scheme that could be considered by Energy Star and other third -party efficiency labeling organizations.
- Conduct a scoping study to analyze the energy efficiency savings potential and performance of a complete DC power architecture for data centers.

## UPS Efficiency and Loading

- 	Manufacturers data for efficiency versus load for current generation static and inertial UPS.

***Based on review of more than 100 static UPS models***

- UPS Systems

## UPS Measured Performance

***Sample of 12 field measurements.***

- UPS Systems

## Measuring UPS Efficiency - “High Efficiency” Option

- Measured Result

- Manufacturer Spec

***On average, existing high efficiency modes can make a 4 to 5 % difference in UPS efficiency.***

- Source: EPRI PEAC

- UPS Systems

## Analyzing UPS Performance in “High Efficiency” Option

- Analyzing UPS Performance in “High Efficiency” Option

***In “high efficiency” mode, there can be one cycle ***
***(16.6 msec for 60 Hz) of voltage deviation on UPS output.***
***Power supplies downstream of UPS can ride through this.***

- Source: EPRI PEAC

## Research of Inertial Units

***Quoted efficiencies are in the 96% range and higher; we will be measuring actual performance in field/lab tests***

- Caterpillar

- Pentadyne

- Piller

- UPS Systems

## Labeling

- Coordinating with International labeling effort addressing quality & efficiency.

- Possible UPS efficiency labeling criteria

- UPS Systems

## Labeling will consider non-energy,reliability issues

- UPS Systems

- Labeling will consider non-energy,reliability issues

## Power Supply Activities 

- Power Supply Activities

- Measure efficiencies of current server power supplies
- Field testing to document achievable energy savings
- Recommend new efficiency levels to Server System Infrastructure Initiative (SSI) for consideration
- Assess other PS saving opportunities in DC applications

## Power Supplies Can Be Much More Efficient – Without Affecting Reliability Performance

- The nation’s 3.1 billion power supplies waste about 3 to 4% of the entire U.S. electricity bill
- Worst designs are 30 to 50% efficient
- Designs already exist in the market that can bring power supply efficiencies to the range of 75 to 93% with big non-energy benefits
- More efficient designs will be developed if there is incentive.

## A consistent test protocol using a standard loading guideline & test report format will allow more visibility on power supply efficiency

**Notes:**
Sample of our testing report – similar to the desktop power supply study

## Server Power Supply Efficiency Test Data: Current Market

- Source: EPRI PEAC

**95****th**** Percentile**

**Median**

- % power supply loading

- efficiency

## Importance of a Flat Power Supply Efficiency Curve

- More design focus on efficiency when
- lightly loaded is needed

**Notes:**
Since PS loading are low it is important to have a flat efficiency curve as much as possible 

## Goals of the Power Supply Task

- Long term:
- Move the market towards widespread adoption of energy efficient PS in data centers
- Create an energy efficiency labeling program such as ENERGY-STAR® for server power supplies

## Power Supplies in IT Equipment

## Power Supplies in IT Equipment

## Slide 42

## Server Power Supply EfficiencyLab Test Setup

- Electronic Load Banks

- Yokogawa Digital Power Meter

- Fluke 41 Power Harmonic Analyzer

- Power Supply Load Test  Fixtures

- Server Power Supply

- Computer Interface

- Server Power Supply EfficiencyLab Test Setup

## Overall Computing Efficiency

- Performance Metrics

- Very Low Processor Activity...

- ...does not relate to very low power consumption

*Most of the time the GHz processor is doing activities that **can be done by a MHz processor but the input power consumption is not changing much*

## Performance Metrics -limited activity includes:

- Performance Metrics -limited activity includes:

- An assessment of:
- Server activity profile based on application/server type
- Correlation of server activity and power consumption
- Work with Intel, AMD, IBM, HP, and potentially others to reach consensus on metrics for some applications.
- Develop efficiency guidelines based on performance metrics

## LBNL’s Role in Demonstrations

- Demonstrations

- Scoping demonstrations of technologies or strategies to improve energy efficiency in high-tech buildings
- Showcase new/emerging or under-utilized technologies or approaches

## Currently Planned Demonstrations

- Heat removal from servers without fans
- DC powering rack of servers
- Air management improvements (PG&E)

- Demonstrations

## Conclusion

- Many strategies to improve energy performance in a data center can be implemented with no impact on reliability – in fact, many will actually improve reliability and lower capital cost.
- Major industry firms are interested in supporting efficiency (and reliability) improvement.
- If you want more efficient data centers – ask for them.

## Thank You

- Questions?
- Bill Tschudi, Principal InvestigatorLawrence Berkeley National Lab510.495.2417wftschudi@lbl.gov
- http://hightech.lbl.gov