Post on 20-Feb-2017
Cold-Climate Research Round-Up
A Bi-Annual Webinar Series | Center for Energy & Environment and Seventhwave
On the ground impacts & opportunities for leading edge, clean energy technologies & services.
The PurposeA semi-annual webinar series to share leading field research & expertise on efficient and clean energy solutions, particularly relevant for cold climate applications.
Next webinar: July 2017
Our Expertise• Conduct primary research in the field• Produce market characterizations & potential studies• Provide training & engagement to convey new info• Provide services and consulting to entities that are looking to
increase clean energy & conservation
CEE | 8 Dedicated research staff Seventhwave| 5 dedicated research staff
Today’s Round-Up• Commissioning for daylighting controls • Optimizing operation of buildings with indoor pools• Energy Recovery Ventilation effectiveness• Maximizing energy savings from Demand Control Ventilation• Cold-Climate Variable Refrigerant Flow optimization• Innovative aerosol envelope sealing • Next generation Air Source Heat Pumps • Hybrid geothermal achieves highest performance
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Many of these projects were supported by a grant funds from the MN Department of Commerce, Division of Energy Resources through the Conservation Applied Research and Development (CARD) program.
Today’s Round-Up• Commissioning for daylighting controls | Seventhwave• Optimizing operation of buildings with indoor pools• Energy Recovery Ventilation effectiveness• Maximizing energy savings from Demand Control Ventilation• Cold-Climate Variable Refrigerant Flow optimization• Innovative aerosol envelope sealing• Next generation Air Source Heat Pumps • Hybrid geothermal achieves highest performance
Today’s Round-Up• Commissioning for daylighting controls • Optimizing operation of buildings with indoor pools | CEE• Energy Recovery Ventilation effectiveness | CEE• Maximizing energy savings from Demand Control Ventilation• Cold-Climate Variable Refrigerant Flow optimization• Innovative aerosol envelope sealing• Next generation Air Source Heat Pumps • Hybrid geothermal achieves highest performance
Areas of expertise: Energy efficiency programs Field research Market characterization High performance design Education and training
Commissioning for Daylighting
Controls
Minnesota Conservation Applied Research and Development (CARD) Grant Program
Background and Objective
1. Photosensor
2. Controller
3. Dimming Unit
Research Approach
Monitored 20 spaces across 10 buildings
Period 1 Energy
Period 1 Savings
Current without
photocontrol
Period 3 Energy
Period 3 Savings
Results and Recommendations
23% savings before Cx, increased to 43% with Cxseventhwave.org/mndaylighting
Research
Financing Policy
Programs
Discover + Deploy the most effective solutions for a healthy, low-carbon economy
Planning & Consulting
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Optimizing Indoor Public PoolsA high energy intensity area with specialty HVAC systems
Russ Landry P.E. | Senior Mechanical Engineer
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Indoor Public PoolsWhy we took a look | We’ve seen big energy saving opportunities in other facilities with specialized HVAC systems, such as ice arenas.
Research Objective | Determine energy cost savings from improvements & develop guides for operators and recommissioning providers.
Extent of Project Efforts• Literature review & identification of indoor public pools in Minnesota• Surveys of 30 sites• Recommissioning and savings verification for 5 sites• Guides for pool operators and recommissioning providers.
Notable Previous Work• Pool operator certification manuals• DOE sponsored RSPEC! software
Conducted Jan 2014 – May 2017
Indoor Public Pool Optimization
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Technology in Brief
Indoor Public Pool Optimization
Pool Water Heating & Filtering
Space Ventilation, Heating & Dehumidification
84°F 55% RH
82°F
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Headline Findings & Observations
Energy & Cost Savings• Some consistent, “prescriptive” type opportunities• Site-specific control & operational “problems”• Some “common wisdom” not true for cold climates• Biggest savings for heating fuel (some electric hvac)
Barriers to Field Implementation• Contractor & manufacturer execution of control details• Often poor BAS link with HVAC & pool water heating• User & operator upkeep: cover & controls
Bright Spots & Opportunities • Cover• Cost-effective control fixes
Indoor Public Pool Optimization
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Highlights of Preliminary Savings
Indoor Public Pool Optimization
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Benefits Beyond Energy
Building Operators• Reduced Comfort Complaints• Simple Actions with Clear Directions from Operations Guide
Building Owners• Reduced Comfort Complaints• Equipment Longevity• Facility Longevity
Indoor Public Pool Optimization
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How to Use This Information
How you can use this information today, take action, or access more tools…• www.mncee.org/pool• http://smartenergy.arch.uiuc.edu• http://www.rlmartin.com/rspec/software.htm
Indoor Public Pool Optimization
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Energy Recovery in Commercial and Institutional BuildingsDo energy recovery systems meet performance expectations?
Josh Quinnell Ph D | Senior Research Engineer
Minnesota Conservation Applied Research and Development (CARD) Grant Program
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C&I Energy RecoveryWhy we took a look • Anecdotal impression that ERVs may not live up to savings potential
Research Objective • Characterize ERVs in Minnesota, determine extent of problems, study a
subset of representative ERVs in detail
Extent of Data Collected • Data collected on 400 commercial & institutional ERVs• Screened 30 ERVs for study• Selected 9 units for detailed study, measurements, and long term monitoring
Notable Previous Work • Prior work is design focused, usually on the cooling side • Stops short of the practical issues associated with expectations, installation,
and operations
Conducted Jan 2014 – Dec 2016
Commercial and Institutional Energy Recovery
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Exhaust Air-to-Air Energy Recovery Ventilation (ERV) in Brief
• Purpose: Transfer energy between exhaust air and outside air to lower energy load of building ventilation
• Relevance: Increasing code requirements
• Performance Expectations:• 40 - 85% heating savings• 0 – 20 % cooling savings
Commercial and Institutional Energy Recovery
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General Findings & Observations
Expectations: ERVs are just another HVAC system• Properly designed, installed, and operated ERVs typically achieve
design performance
Reality: Barriers to ERV Performance are practical• There are no consistent expectations for ERV performance • 80% of the problems occur during installation or operation• Problems persist because expectations aren’t established and
other HVAC systems compensate
Opportunity: Most lost recovery is an easy fix• A small number of issues were responsible for the vast majority of
energy penalties
Commercial and Institutional Energy Recovery
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Problems on ERV systems• 75 issues discovered and 51 corrected• Energy savings increased $40,683 -> $57,851 for 9 units or 0.30
to 0.42 $/supply-cfm• 15% of issues responsible for 92% of lost energy recovery
Control se
quence
Neglected m
aintenance
Installa
tion issue
Communication
Sensors
Part fa
ilure
Setpoint
Operator overr
ide
Design iss
ue
Off design operation
Schedulin
g0
2
4
6
8
10
12
Freq
uenc
y
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Problems Encountered on ERVs
Commercial and Institutional Energy Recovery
High functioning units – 33% units / 8% problems• Design-bid-build projects• Robust documentation & commissioning process• Typically found only neglected maintenance items
Functioning units – 33% units / 38% problems• Awareness of minor problems, frustration or confusion about unit
operation• Odd sequencing, BAS issues, sensor, scheduling, and set point problems
Dysfunctional units – 33% units / 53% problems• Awareness of minor problems, no awareness of major ones• Heat recovery casually disabled and poor installation
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Opportunities
Commercial and Institutional Energy Recovery
Text book examples of ERV applications are common!• We know that dramatic energy savings are possible in practice• Robust documentation, commissioning, and hand off are key to success• Improving general maintenance is still an opportunity for the best systems
Most problems don’t seriously inhibit energy recovery!• Consistent with the types of problems reported outside this work• There is still a huge opportunity; these problems indirectly impact
expectations and impressions of energy recovery –typically unrelated to actual recovery performance
It’s easy to identify dysfunctional units!• If a unit runs 5 ᵒF– 45ᵒF and above 75ᵒF, 85% savings are achieved• In many situations it is easy to casually disable energy recovery, but it’s also
easy to re-enable it and perform basic training about specific controls
Today’s Round-Up• Commissioning for daylighting controls • Optimizing operation of buildings with indoor pools • Energy Recovery Ventilation effectiveness • Maximizing energy savings from DCVs | Seventhwave• ccVariable Refrigerant Flow optimization | Seventhwave• Innovative aerosol envelope sealing• Next generation Air Source Heat Pumps • Hybrid geothermal achieves highest performance
Maximizing Energy Savings from Demand
Control Ventilation
Minnesota Conservation Applied Research and Development (CARD) Grant Program
Background and Objective
Sensor
VAV Boxes
Central and/or Zone Control
AHU
Source: http://i.stack.imgur.com/4WKDC.jpg
SAOA
RA
Research Approach
96 systems around Minnesota
Results and Recommendations
Results and Recommendations
seventhwave.org/dcv
• Most room for improvement was found in basic design
• Proper commissioning (or recommissioning) has a significant impact on its performance
• Identifed four key program opportunities
Cold-Climate Variable
Refrigerant Flow Optimization
Background and Objective
Research Approach
o What should the mechanical room setpoint be?o How to operate louvers?o Should supplemental heating be natural gas or electric?o What is the optimal defrost strategy?o How to handle condensate from supplemental heater?
Energy Balance Energy Consumption1. Outdoor units
• heating and/or cooling2. Supplemental heating3. Auxiliary heating
• baseboard4. Mechanical room
ventilation fan
Results and Recommendations
OptimalThe optimal mechanical room setpoint occurs at a temperature close to, but higher than, the temperature at which the VRF system’s heating efficiency and capacity are significantly reduced.
o Supplemental heating should be provided by natural gas.o Demand defrost saves 4% of VRF energy as compared
to timed defrost.
seventhwave.org/cold-climate-vrf
Today’s Round-Up• Commissioning for daylighting controls • Optimizing operation of buildings with indoor pools • Energy Recovery Ventilation effectiveness • Maximizing energy savings from Demand Control Ventilation• Cold-Climate Variable Refrigerant Flow optimization• Innovative aerosol envelope sealing | CEE• Next generation Air Source Heat Pumps | CEE• Hybrid geothermal achieves highest performance
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Aerosol SealingA new building envelope technology for renovation & new construction projects
Dave Bohac P.E. | Director of Research
Minnesota Conservation Applied Research and Development (CARD) Grant Program
Partners
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Multifamily Aerosol SealingWhy we took a look • Proven duct sealing technology. UC Davis/WCEC performed lab tests
and limited demonstration for envelope sealing
Research Objective • Demonstrate leakage reduction in multifamily buildings and refine sealing
protocol
Extent of Data Collected • Sealed 16 units in 3 new construction buildings• Sealed 9 units in 3 existing buildings• Modeled energy savings and air flow impacts
Conducted Jan 2014 – July 2016
Aerosol Envelope Sealing of Multifamily Buildings
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Aerosol Envelope Sealing – How Does it Do That?• Pressurize apartment• Spray air sealing fog
Aerosol Envelope Sealing of Multifamily Buildings
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Air Sealing Results: New Construction
Aerosol Envelope Sealing of Multifamily Buildings
• Average leakage reduction of 81%
• Average leakage = 0.7 ACH50 after sealing
• All units at least 80% tighter than EPA ENERGY STAR requirement of 0.3 CFM50/sf
• Half of the units met 0.6 ACH50 passive house standard
• 69 therms/yr savings (3 to 0.6ACH50 reduction)
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What Gets Sealed?
Aerosol Envelope Sealing of Multifamily Buildings
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What Gets Sealed?
Aerosol Envelope Sealing of Multifamily Buildings
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Air Sealing Results: Existing Buildings
Aerosol Envelope Sealing of Multifamily Buildings
• Median leakage reduction of 75%
• Medain pre-leakage of 13.7 ACH50 reduced to 3.2 ACH50
• 60 to 200 therms/yr savings depending on existing leakage
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Non-Energy Benefits• Improved IAQ from reduced air transfer between units
• Reduced sound transmission between neighbors and outdoors
• More reliable method for meeting tightness requirements and test is part of service
Aerosol Envelope Sealing of Multifamily Buildings
Mechanical ventilation required after sealing and balanced ventilation needed for tighter units
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Future Work• Final report available soon
• DOE Building America: integrate sealing into new house construction process
• WCEC – Department of Defense large building sealing
• Aeroseal has started commercial work and developing contractor network Q4 2017
Aerosol Envelope Sealing of Multifamily Buildings
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Next generation Air Source Heat Pumps Are the new generation of air source heat pumps a good fit for cold climate heating?
Ben Schoenbauer | Senior Mechanical Engineer
Partner
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Field Assessment of Cold-Climate Air Source Heat Pumps (ccASHPs)Why we took a look • Technological advancements have expanded the applicable climates• Potential to serve an under-represented sector
Research Objective• Characterize system performance and installation challenges • Assess the implications to policy and programs
Extent of Data Collected• Data collected in 6 homes over 2 heating seasons
Notable Previous Work • Research and program development in “cool” climates (NE and NW)
Conducted Jan 2015 – Aug 2017
ccASHPs
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ccASHPs in Brief
• Technology Purpose: To provide energy efficient space conditioning through the transfer of heat between the exterior and interior of a home (a.k.a. an alternative primary source)
• Applications: Potential to meet the needs of an under- served group (homes heated with delivered fuels or electricity)
• Expectations: 1.5x or larger increase to space heating COP while maintaining comfort
ccASHP
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Findings & Observations
Expectations and Concerns• Can ASHP really transfer heat at cold outdoor conditions?
Reality from the FieldccASHPs provide benefits down to and beyond 10 ⁰ F, including:
• COPs more than 1.5x as efficient as baseline systems• Sufficient capacities to meet the heating loads of most MN homes• Sufficient airflow and temperatures to condition most homes comfortably
Opportunity for the Future• Integration with existing systems• Initial costs• Eliminate or minimize the need to backup
ccASHP
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Bright Spots & Opportunities• Site energy savings• Energy cost reductions• Reduced reliance of delivered fuels and/or peak electricity
Benefits Beyond Energy • Opportunities to serve in rural communities
How You Might Use this Information• Utilities:
• Heating rebates & programs that service this technology
• Contractors: • A signal that new gen products are appropriate in MN & guidance on when
• Architects & Engineers: • Consider as viable technology in all parts of MN
ccASHP
Today’s Round-Up• Commissioning for daylighting controls • Optimizing operation of buildings with indoor pools • Energy Recovery Ventilation effectiveness • Maximizing energy savings from Demand Control Ventilation• Cold-Climate Variable Refrigerant Flow optimization• Innovative aerosol envelope sealing • Next generation Air Source Heat Pumps • Hybrid geothermal achieves highest performance | Seventhwave
Hybrid Geothermal
Achieves Highest
Performance
Background and Objective
Background and Objective
Example system Cooling dominated Coupled hydronic loops Series supplemental device Dedicated supplemental pump
Research Approach
Cashman Equipment (cooling dominant)300k ft2 equipment dealer in Henderson, NV
East Career and Technical Academy (cooling dominant)250k ft2 vocational high school in Las Vegas, NV
Tobacco Lofts (heating dominant)74k ft2 multifamily building in Madison, WI
Results and Recommendations
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
East CTA Cashman Tobacco Lofts
Energy and
Water Cost ($/ft2)
Conventional HVACGSHP SystemHybrid GSHP System
….for East CTA building
$8,000,000
$9,000,000
$10,000,000
$11,000,000
$12,000,000
GSHP Hybrid Conventional
$8,000,000
$9,000,000
$10,000,000
$11,000,000
$12,000,000
GSHP Hybrid Conventional
Cooling Tower CostGHX CostOther Costs
Ann
ual C
osts
($/ft
2 )
Results and Recommendations
Adjusted Internal Rate of Return
Cashman East CTA Tobacco LoftsHybrid instead of Conventional 10% 12% 9%GSHP instead of hybrid 5% 4% 1%
Results and Recommendations
seventhwave.org/hygchp
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Resources for a deeper lookSeventhwaveDaylight control commissioning| www.seventhwave.org/mndaylightingDemand Control Ventilation | www.seventhwave.org/dcvHybrid Geothermal Controls | www.seventhwave.org/hygchp
CEEEnergy recovery ventilation | www.mncee.org/ervAir source heat pumps | www.mncee.org/heat_pumpsPool facility operations | www.mncee.org/poolAerosol sealing | www.mncee.org/aero
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Your Turn...
Question & Answer
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Series Sneak Peak | July 2017• Characteristics & savings opportunities for residential high energy users• Energy saving opportunities in mobile homes• Home HVAC install and maintenance opportunities• Small embedded data center energy saving strategies• Commercial energy codes support program pilot
Upcoming Deeper Dive Webinars• Roof-top Unit Market Characterization | March 2017• Aerosol Envelope Sealing | spring 2017• Energy Recovery Ventilation Research Results | summer 2017• Commercial Duct Leakage Reduction Opportunities | spring 2017
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ContactsDave Bohac| Director of Researchdbohac@mncee.org
Russ Landry| Sr. Mechanical Engineerrlandry@mncee.org
Josh Quinnell| Sr. Research Engineerjquinnell@mncee.org
Ben Schoenbauer| Sr. Research Engineerbschoenbauer@mncee.org
Doug Ahl | Director of Researchdahl@seventhwave.org
Scott Schuetter | Sr. Energy Engineersschuetter@seventhwave.org