1. Leading the Way to a Clean Energy Future
A holistic approach to energy efficient data centers
Steve Hammond

2. Laboratory Snapshot
Only National Laboratory Dedicated
Solely to Energy Efficiency and
Renewable Energy
• Leading clean-energy innovation for 35 years
• 2540 employees with world-class facilities
• Campus is a living model of sustainable
energy
• Owned by the Department of Energy
• Operated by the Alliance for Sustainable
Energy

3. Scope of Mission
Energy Renewable Systems Market
Efficiency Energy Integration Focus
Residential Solar Grid Private Industry
Buildings Infrastructure
Wind and Federal
Commercial Water Distributed Agencies
Buildings Energy
Biomass Defense Dept.
Interconnection
Personal
Hydrogen State/Local
and Battery and
Govt.
Commercial Geothermal Thermal
Vehicles Storage International
Transportation

4. Focus on Buildings
Status U.S. Buildings:
• 39% of primary energy
• 71% of electricity
• 38% of carbon emissions
• +3% of electricity by data centers
DOE Goal:
• Cost effective, marketable zero energy
buildings by 2025
• Value of energy savings exceeds cost of
energy features on a cash flow basis
NREL Research Thrusts
• Whole building systems integration of
efficiency and renewable features
• Modeling and Simulation: building energy
optimization tools
• Building integrated PV
National Renewable Energy Laboratory Innovation for Our Energy Future

5. Efficient Buildings
• NREL Research Support Facility
• LEED Platinum office building
• Uses 40% of the energy of typical office
buildings
• Model for sustainable commercial office
buildings
• On track for net-zero energy building.
• Space for ~1200 employees
• Construction cost $260 per sf similar
to other metro area buildings

6. Key Design Features
• Fully day lit office wings
• Continuous insulation precast wall panels
with thermal mass
• Radiant heating and cooling
• Outdoor air preheating
• Transpired solar collector
• Datacenter waste heat
• Crawl space thermal storage
• Aggressive plug load control strategies
• Data center air-side economizer, hot aisle
containment
• Roof top and parking structure-based PV
http://www.nrel.gov/news/rsfnews/awards.html

7. Every Watt Counts
• Whole building energy use = 283 watts per occupant
• Includes enterprise data center.
• Personal habits represent ~1/3 of typical building energy use
• For every 1 watt continuous we save,
we avoid $33 of PV needed to offset this 1 watt
National Renewable Energy Laboratory Innovation for Our Energy Future

8. Energy System Integration Facility
LEED Platinum Building
8

9. ESIF HPC Data Center
• Showcase Facility • High Performance Computing
– 10MW, 10,000 s.f. – Petascale+ HPC Capability in 2012
– Leverage favorable climate – 20 year planning horizon
– Use evaporative rather • 5 to 6 HPC generations.
mechanical cooling. – Energy Data Hub
– Waste heat captured and • Data mgmt, mining, analytics
used to heat labs & offices. – Insight Center
– World’s most energy efficient • Scientific data visualization
data center, PUE 1.06! • Collaboration and interaction.
– Lower CapEx and OpEx.
Leveraged expertise in
energy efficient buildings to
focus on showcase data
center.
Chips to bricks approach.
National Renewable Energy Laboratory Innovation for Our Energy Future

10. Data Center Sustainability
IT Power Consumption
Energy Re-use
Facility PUE
Sustainability is a function of optimizing all three factors.

11. ESIF Data Center Electrical System
• Primary utilize 480 volt distribution to
enhance energy efficiency, eliminate the
losses and heat associated with PDU’s
and step down transformers.
• UPS for 10% of peak load
– Sufficient duration to allow generator to spin
up and protect critical components.
• Operate in ASHRAE TC 9.9
recommended range 99% of the time
(~87 hours per year in allowable).
– Allow forays into higher temps
• Dashboards to report instantaneous,
seasonal and cumulative PUE values.

12. ESIF Data Center Mechanical System
• Focus on warm water cooling
– HPC equipment cooled indirectly with tower water.
– Pumps/water more efficient fans/air.
– Can capture 100% heat load dissipated to liquid
– Can manage up to 10% heat load to air.
• “Cooling” supply temp, 75F
• Return temp, 95F (20F delta T) or warmer
• Waste heat used in cold months to heat lab and
office space, temper inlet air, or ejected directly
outside when not needed.
• Waste heat also fed to district heating system.

13. NREL ESIF Data Center Cross Section
• Data center equivalent of the “visible man”
– Reveal not just boxes with blinky lights, but the inner
workings of the building as well.
– Tour views into pump room and mechanical spaces
– Color code pipes, LCD monitors

14. Critical Data Center Considerations
• Warm water cooling
• Pumps trump fans.
• Water much better working
fluid than air.
• No condensation worries.
• High power distribution
• Eliminate conversions.
• Think outside the box
• Don’t be satisfied with an
energy efficient data center
nestled on campus surrounded
by inefficient laboratory and
office buildings.
• Innovate, integrate, optimize.

15. Questions?
Discussion
National Renewable Energy Laboratory Innovation for Our Energy Future