Post on 19-Jul-2020
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 1
Zero Energy Part 3Systems: Renewables + HVAC + DHW
What do I know?!
I’m not a mechanical engineer!!
Session Topics
ZNE Part 1 takeawaysDesign integrationChoosing systemsConstruction follow‐throughClimate‐specific examples
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 2
ZNE Part 1 Takeaways: PROCESS
1. Set early, specific performance goals
2. Focus on efficiency3. Adopt an integrated
process
4. Learn from CASE studies (“Copy And Steal Everything”)5. Revisit goals & check progress often
ZNE Part 1 Takeaways: PEOPLECommitmentCreativityExperienceEngagement
(Code for “plays well with
others”)
Design integration happens only if the project team is well integrated –
works together (in tandem, not in series).
© Pressmaster | Dreamstime.com © Alexei Averianov| Dreamstime.com
THIS
THAT
DESIGN INTEGRATION
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 3
© Eraxion | Dreamstime.com
Good enclosure reduces HVAC
loads
Smaller HVAC = more budget for
enclosure Lower cooling loads reduces HVAC size
Less lighting energy reduces cooling loads
Good daylighting
reduces lighting loads
INTEGRATION recognizes that each aspect of building design and each discipline influences
the others.
Lower enclosure
loads
Lower HVAC loads Lower
lighting loads
INTEGRATION results in savings across multiple systems.
Smaller renewable energy system
[ORDINARY]Design+
ZE Construction≠
ZE Buildings
ZE Design+
[ORDINARY]Construction
≠ZE Buildings
Zero Energy is a Recessive Geneso …
QUALITY IS CRITICAL
Design + Construction must be integrated.
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 4
What’s the Ideal Integrated Team?The fewest people with the required skills & attributes
(commitment, creativity, experience, engagement)
CONSTRUCTION MANAGEMENT
AIR SEALING
INSULATIONPLUMBING
MECHANICAL ELECTRICALSTRUCTURAL
ARCHITECTURE
The (myth of the)Design‐ConstructionDIVIDE
TIME
ACT
IVITY
CONSTRUCTIONDESIGN
How we typically think about building
creation
The (reality of the)Design‐Construction CONTINUUM
DESIGNTIME
ACT
IVITY
What’s really happening
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 5
How Integrated Design + Constructionproduces better buildings
Illustrations courtesy of Will Lichtig.
Integrated design & deliveryBusiness as usual
PLUS: reduced change orders, cost overruns, construction time, liability; and increased productivity, harmony, happiness, achievement of goals!
Each one affects the others.
CHOOSING SYSTEMS
Choosing RenewablesMost ZE homes in North America will have photovoltaics
Many ZE homes will have solar thermal systems
Few ZE homes will have other types of renewables
Consider/ eliminate in reverse
order
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 6
PVs to offset 20,000 kWh/yr for:
Grid load (KWh/yr)
Annual onsite PV production
(KWh/yr)
PV area needed for ZNE (sq. ft.)
Source energy50% electric + 50% gas 46,000 13,529 700
Site energy OR Source energy100% electric
68,000 20,000 1,050
How much roof area will you need?
(Besides Loads) Fuel Mix & ZNE Definition Drive
Renewable System Size
Renewable Energy Context FactorsClimate & Microclimate
Insolation (solar radiation)Wind amount & typeIs there sun/wind where you need it?
CommunityRegulations pro/conNeighbor opinions
SpaceOn roof or off? Form: orientation, tilt, shapeCompeting uses: PV, solar thermal, plantsWind turbine sound & vibration
0
10
20
30
40
50
60
70
80
90
100
Marine (San Francisco) Hot/Mixed Dry(Phoenix)
RENEWABLES
ENERGY EFFICIENCY
Maximize cost‐effectivenessBalance efficiency vs. renewables
Percent Energy Savings:Efficiency vs. Renewable Energy
Energy Free Figure 2‐5, page 26, based on data from Navigant
Marine (San Francisco)
Cold(Chicago)
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 7
System EconomicsThe optimum systems package (renewable+ HVAC+DHW) considers:
Energy performance as a function of investmentEfficiency (reduction) vs. renewables (production)
Competing efficiency measures
Competing renewables
Opportunities to eliminate systems, simplify & save on maintenance
Availability of qualified labor
RUN THE NUMBERS –COSTS VARY BY TIME & PLACE
Choosing HVAC SystemsCan you eliminate air conditioning?
Load reduction strategies:1. Enclosure
insulation
reflective surfaces
thermal mass
2. Passive ventilation
3. Fans
4. Indirect evaporative cooling when appropriate
THERMAL BATTERY EFFECT
STACK EFFECT
Choosing HVAC SystemsForced air, or radiant, or both?
Decision factors:If you will have AC, forced air:
will be the most economicalmeans 1 system for space conditioning, not 2
Will the home be occupied 24/7, or only nights, mornings, and weekends?
Occupant‐specific vs. occupant‐neutral design?Does the outdoor temperature swing hot‐to‐cold (or vice versa) quickly? How much?Are you renovating, or building a new structure?Does anyone in the home have respiratory challenges?
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 8
Heating Performance StrategiesKey variables:1. Proper sizing – not too small … but not too BIG!
2. Efficient distribution
3. Quality installation
4. Efficient equipment©Anke Van Wyk | Dreamstime.com
You’ll need a very energy‐savvy MECHANICAL ENGINEER and/or MECHANICAL CONTRACTOR!
often the only factor considered
Domestic Hot Water
EVACUATED‐TUBE
COLLECTORS
DHW performance factors:Efficient equipment
Distribution1st choice: compact layout
2nd choice: on‐demand recirculation
Drain‐water heat recovery
Solar pre‐heat –choose based on:
Payback
Maintenance
Performance relative to more PV
FLAT‐PLATE COLLECTORS
Solar Water Heating Considerations
Domestic hot water year‐roundSpace heating? fall / winter / springAll‐electric projects may use heat pump for HVAC + DHW; does a second system make sense? Swimming pool or spa? summer or year‐round?
DIFFERENT NEEDS for space heating vs. DHW
vs. pool
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 9
Focus on QUALITY
CONSTRUCTION FOLLOW‐THROUGH
ZE performance requires integration of Design + Construction
Air conditioner sizing
Good thermal enclosure
HVAC installed properly
A/C capacity (tons)
Standard n/a n/a 4
Efficient/ZNE Loads / 2 Performance x 2 1*
OR LESS due to smaller ducts that fit inside thermal & pressure boundaries
This can only happen with effective collaboration between design team and contractors
and QUALITY MANAGEMENT.
75% SMALLER!
Quality Managementis essential to meeting design goals
16” uninsulated bypass duct with no weight on barometric
damper
No plenum attachment
No TXV bulb attachment
Outdoor air duct damper with no wires attached
THESE ARE NOT
DESIGNPROBLEMS
!Photos courtesy of Rick Chitwood
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 10
© Scott Griessel | Dreamstime.com
ZE Success Principles1. If your PROCESS IS SOUND (well integrated
throughout design & construction), good outcomes will follow.
2. A sound process, carried out by the RIGHT PEOPLE*, all but guarantees a good project. (*committed, creative,experienced, engaged)
3. The party left out is the one who will cause trouble.
© Ann Edminster / Design AVEnues LLC 2011
AnnEdminster.comZERO ENERGY CONSULTING
clear GOAL+ right PEOPLE
+ right PROCESS
0
Now over to George Sullivan …
CLIMATE‐SPECIFIC EXAMPLES
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 11
Systems, Players and Projects
Net Zero Analysis & Design Corp.George D. Sullivan
Sr. Principal©All Rights Reserved
System Influencers that Impact Energy Use• Building Envelope Design
• Orientation
• Shading
• Airtightness
Identify Project Energy Target
• Energy Star version 3 revision 8*
• Zero Energy Ready Home**
• Passivhaus**
*Requires larger site renewable energy system**Can be net zero or net positive
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 12
Equipment Fuel Choice
• Impacts Building Energy Use
• Natural Gas requires combustion and exhaust penetrations through the building envelope
• Thermal bridges increase energy consumption
• Electrical equipment has no combustion and exhaust penetrations through the building envelope
Identify Site Renewable Energy Options• Geothermal
• Primary Heating and Air Conditioning and DHW
• Ventilation intake air energy use can be offset with a geothermal balanced system
• Photovoltaics • Roof, Building or Ground Mount
• System can be sized to run a heat pump DHW System
Coordinated Construction Plan Set • Requirements
• All Important Notes ‐ Air Sealing Details, Penetration Details
• Construction Detail Reference – Thermal Breaks, Drainage Plane
• Calculations and Models – Required information for trades
• Equipment Details ‐ Cut sheets on all equipment
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 13
System Models
• Modeling HVAC
• Manual J room loads • block loads
• Rule of Thumb
• Manual S equipment sizing
• Manual D duct design
• Modeling Plumbing Pipe Loads
• Cold Water and Live Water Sprinkler Loads
• DHW Generation and Distribution Loads
• DWV Pipe Loads
Selecting Subcontractors
• Selecting MEP Subcontractors
• Project Specific by Trade
• General Requirements – Energy Star Project Experience
• Certification Requirements
• ACCA – Mechanical Contractor• Solar Installer Certification – Electrical Contractor• Water Sense – Plumbing Contractor
Learning Curve
• Mechanical and Ventilation Systems
• Energy Star Version 3 –
• VRF Zoned or GFA System• Balanced Ventilation and Kitchen Hood Supply Air• DHW Systems, Instantaneous, HP DHW, or Energy Efficient Hot Water Tank
• Setback Thermostat• Learning Energy & Control System
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 14
Learning Curve
• Mechanical and Ventilation Systems
• Zero Energy Ready Home –
• VRF Zoned System• Geothermal Balanced Ventilation and Kitchen Hood Supply Air• DHW Systems, Instantaneous, HP DHW, or VRF Driven System• VRF Thermostat (set it and forget it)• Learning Energy & Control System
Learning Curve
• Mechanical and Ventilation Systems
• Passivhaus –
• VRF Zoned System• Geothermal Balanced Ventilation and Kitchen Hood Supply & Extract Air
• DHW System ‐ VRF Driven System Energy Recycling from the Building to DHW
• VRF Thermostat (set it and forget it)• Learning Energy & Control System
3 Flat Acres – Zero Energy Ready Home
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 15
3 Flat Acres – Zero Energy Ready Home
3 Flat Acres – Zero Energy Ready Home
• ERV Earth Tube Supply & Exhaust
• (Geothermal System)
• Solar Thermal
• Zero Energy Ready Home Building Shell
Full Revolution Farm – Hospitality Passivhaus
Therm Modeling ‐ All details
All Window and Door Install Detail
Over Insulationof
Window and Door Frames reduces the U Value Cutting Energy Loads
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 16
Full Revolution Farm – Hospitality Passivhaus
• Passivhaus Building Envelope
• Building Orientation Southeast
• Summer Shading
• 65% Window and Glass Door
• Southeast Side of Building
• Building Designed –• Optimized Solar Thermal Collector
• No Heating Degree Days
Full Revolution Farm – Hospitality Passivhaus
• 3 ERV ‐ Earth Tube Balanced Ventilation Systems
• Including 2 Kitchen Hoods
• 9 Zone VRF Geothermal System
• Harvests all Internal Loads to Heat the Domestic Hot Water
Carl House – Zero Energy Ready Home• Commercial Construction
• Completely Steel Framed
• Advanced Thermal Bridge Free Wall, Roof, and Floor System
• Advanced Thermal Bridge Free Window and Door Install
• FORTIFIED for Safer Living® Silver
• Renewable Energy Systems
• Southeast Orientation • House acts as a Solar Thermal Collector
• ERV Earth Tube Balanced Ventilation
• Photovoltaic System• Offset all building Loads
B4‐2016 ZNE Part3
© Ann Edminster / Design AVEnues LLC 2016 17
Carl House – Zero Energy Ready Home
• Designed 0.3 ACH50
• VRF Geothermal System
• Photovoltaic System oversized to power HP DHW System
• Zero Energy Ready Home – Certified off of Plans
Carl House – Zero Energy Ready Home
• Learning Energy Control System
• Advanced Control and Decision Making
• Learning Based on Occupancy Habits
• Lighting
• Environmental Controls
• DHW System
• PV System Power ‐ Time of Day Shedding to the Grid
Thank YouGeorge Sullivan
&Net Zero Analysis & Design Corp. Team