Energy Efficient HVAC for Commercial Buildings
Mahabir Bhandari, Ph.D.
Building Technologies Research & Integration Center (BTRIC)
Oak Ridge National Laboratory
for
[Green Building Congress, Hyderabad, India]
October 2012
2 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
3 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
4 Managed by UT-Battellefor the U.S. Department of Energy
5 Managed by UT-Battellefor the U.S. Department of Energy
Industry377 MMTC
(25%)
Buildings658 MMTC(43%)
End use breakdown“Considerable room for improvement.”
Savings reported from 134 Energy Savings Performance Contracts (ESPC) projects at US Federal facilities:Building Automation/controls : 18%HVAC : 15%
Other include: SEDS adjustment, computers, cooking, electronics
Total energy:40.4 Quad (2010)
~ 1,020 Mtoe
Source: 2007 Buildings Energy Data Book. Tables 1.1.3, 1.2.3, 1.3.3
6 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
7 Managed by UT-Battellefor the U.S. Department of Energy
System/Building Integration
• Air barriers
• Cool roofs
• Optimal integration of PCM
• Moisture/ durability
• Fenestration System Optimization
• HVAC Components
• HVAC Systems
• Water heater
• Appliances
• Internal Loads
• Lighting
• Wireless sensors
• Wireless based systems for EMCS, FDD, RX or CX
• Demand response
• Design/load analysis
• Advanced computing & visualization
• Auto-tuning of models
• Optimization
System/Building Integration
System/Building Integration
8 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
9 Managed by UT-Battellefor the U.S. Department of Energy
Modeling tools for EE HVAC design/analysis
A comprehensive list of tools: http://apps1.eere.energy.gov/buildings/tools_directory/alpha_list.cfm
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10 Managed by UT-Battellefor the U.S. Department of Energy
Development of 20 IEER Rooftop Unit Development of 20 IEER Rooftop Unit Development of 20 IEER Rooftop Unit Development of 20 IEER Rooftop Unit (RTU)(RTU)(RTU)(RTU)
• Goal: Develop commercial RTU with an IEER of 20 (60% improvement in efficiency) :10- 20-ton cooling capacity
• Tech Approach: Variable-speed compressors, micro-channel HXs, condenser evaporative pre-cooling, desiccant wheel, etc.
– Work with Industry Partner
Parallel refrigeration cycle, tandem system provides major capacity; VS system provides capacity fine tuning and dedicated outdoor air treatment.
Mechanical Systems�18 IEER
Adding Condenser Evap Precooling �20+ IEER
11 Managed by UT-Battellefor the U.S. Department of Energy
Annual Cooling Energy Savings Using Annual Cooling Energy Savings Using Annual Cooling Energy Savings Using Annual Cooling Energy Savings Using High IEER High IEER High IEER High IEER RTUsRTUsRTUsRTUs
• 3 Story, 4,950 m2 , medium Office building
• Baseline 2-speed RTU, IEER of 12.5.
• Only lists the savings in vapor compression systems, not including savings by fans,
economizer, etc.
Average Annual Cooling Energy Saving > 25%.
12 Managed by UT-Battellefor the U.S. Department of Energy
Next Generation Window Air-Conditioner
• Current DOE minimum EER
is 9.5
• 57 million in use in U.S.
• Efficiency improvement
options based on efficiency
& cost impacts
• Conduct design optimization
analyses
• Partner builds lab prototype
• Test prototype to verify
efficiency
• Refine design as needed to
achieve 13.0 EER target
13 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
14 Managed by UT-Battellefor the U.S. Department of Energy
HVACs with Better Controls Save Energy
Packaged ACs with gas heat in retrofit
case -small office, stand-alone retail, strip
mall, supermarket
Strategies : air-side economizer, supply-fan
speed control, cooling-capacity (2 stage
compressor) control, and demand-
controlled ventilation.
Ave. Energy Savings: 24% - 35%
Cost savings : 24%-46%
Payback period: < 3 years
Most savings: Multi-speed fan control and
DCV
Source: PNNL, Report #PNNL-20955
15 Managed by UT-Battellefor the U.S. Department of Energy
Energy Management and Control SystemsEnergy Management and Control SystemsEnergy Management and Control SystemsEnergy Management and Control Systems
EMCS
Sensors & Controls
Standards, Deployment & Industry
Modeling and Simulation
Security
LatencyReliability
Throughput
THYME: Simulating Networked Physical Systems
Controller InverterVapor comp.system and heater
Box
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Rapid Prototyping
Algorithms & Analysis
Fault Detection and Diagnosis
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Occupancy at Buildign Level
Trending and Analysis
•Advanced sensing & control can improve efficiency by 30-50%
•HVAC faults account for 3% of US energy consumption
Current wireless sensor
Platform: $150-$300/node
Proposed Advanced Sensors
Platform: $1-$10/node
Develop Methods and Tools to
Derive Fault Impact
Develop Methods and Tools to
Derive Fault Impact
16 Managed by UT-Battellefor the U.S. Department of Energy
Whole-Building Model Predictive Control
17 Managed by UT-Battellefor the U.S. Department of Energy
High Performance Sustainable Buildings
Existing Buildings
All Non-Industrial campus buildings meet HPSB GP
At Least 15 % HPSB
2015List ofBuildings and Organization Plan
2010
Building 1059certified asLEED Gold
2009Nine existing HPSBs
complete
Deliver 4 new HPSBsEach year through 2015
on-going
EO:
� 15% HPSBs by FY15, 100% over time
� 30% energy intensity reduction 2015 vs 2013
� 28% Scope 2 GHG reductionby 2020 vs 2008
�16% water intensity reduction by 2015 vs 2007
EO:
� 15% HPSBs by FY15, 100% over time
� 30% energy intensity reduction 2015 vs 2013
� 28% Scope 2 GHG reductionby 2020 vs 2008
�16% water intensity reduction by 2015 vs 2007
Standards, Deployment & Industry
HPSB initiative at ORNL
18 Managed by UT-Battellefor the U.S. Department of Energy
OVERVIEW
• Need for energy efficient HVAC systems
• Whole building integration key to HVAC energy efficiency
• Modeling and Design Tools
• Sensors/Controls and BEMS
• Research collaboration
19 Managed by UT-Battellefor the U.S. Department of Energy
Technical Energy-Savings Potential of Selected HVAC Technology Options
• Source: Energy Savings Potential and RD&D Opportunities for Commercial Building HVAC Systems, Navigant Consulting, Inc., http://apps1.eere.energy.gov/buildings/publications/pdfs/corporate/commercial_appliances_report_12-09.pdf
•
1 Quad ~ 25.22 Mtoe = 1.055 x 1018 J
20 Managed by UT-Battellefor the U.S. Department of Energy
Advanced HVAC System Research under CBERD
• Path to Advance Clean Energy (PACE)-R
• Joint Center for Building Energy Research and Development (CBERD) – LBNL/CEPT University
• Areas identified under Advanced HVAC system subtask –ORNL/ MNIT Jaipur and IIT Bombay
– Re-optimized Chilled water options for India
– Refrigerant Charge Monitor
– Non-Compressor DOAS
– Micro Channel Evaporators for Unitary HVAC
– India lead Contacts:
• Dr. Jyotirmay Mathur ([email protected])
• Dr. Milind Rane ([email protected])
Vision: Science-to-application collaboration to accelerate industry’s building energy efficiency (BEE) solutions into market
Questions?
22 Managed by UT-Battellefor the U.S. Department of Energy
Additional
23 Managed by UT-Battellefor the U.S. Department of Energy
Integrated approach – Test buildings
• Evaluate new EE technologies in realistic test bed
• Test chambers do not capture the entire building dynamics
• Industry is reluctant to embrace new design & construction techniques until proven with real buildings
• Occupied buildings are intrusive - Simulated occupancy