2012 06-07 nahb leading suppliers council - zeh final
-
Upload
amber-joan-wood -
Category
Design
-
view
154 -
download
3
Transcript of 2012 06-07 nahb leading suppliers council - zeh final
Driving Innovation in Housing Technology
Building Towards Net Zero
Amber Wood
Manager, Energy Programs
NAHB Leading Suppliers Council
June 7, 2012
2
NAHB Research CenterUpper Marlboro, MD
Housing R&D and laboratory testing Promote innovation Enhancing quality & affordability Promoting high standards for the
building industry
Building America
Private/public R&D partnership sponsored by DOE
Energy-efficient solutions for new and existing housing Technologies/Systems Whole-House Test Homes Quality Processes
4
5Why ZEH?
What is ZEH?
Efficient Envelope
Renewable energy
systems
Efficient Equipment
Annually producing as much energy as consumed
Types of ZEH
7
Builder-Installed Electric nZEH Production Accounts for All Builder-Installed End-Uses
All Electric nZEHProduction Accounts for All Electric
Total House nZEHProduction Accounts for All Electric + Excess to Account for Other Fuels
Net Producing HouseProduce > Consume
8
ZEH Disclaimer
A Zero Energy Home is NOT:
Zero energy consumption Utility independent Energy rationed Energy unlimited
9
The Basics
1. Decrease total energy use
2. Produce energy from renewable sources
Hathaway home, Purcellville, VA. NREL photo archive
10
An Energy Efficient HomeHouse Shell:Added insulation, low-e windows, insulated foundation, overhangs, orientation
Heating & Cooling Equipment:High Efficiency, programmable thermostat, sealed ducts, ventilation
Water Heating: Solar preheat, efficient delivery, low-flow fixtures
Appliances: ENERGY STAR® Label
Lighting:Fluorescent fixtures/ bulbs, daylighting
Plug Loads & Appliances:Homeowner’s choice to decrease use
Air-sealing:Seal vents, holes and gaps through walls and roof
11
Effect of Efficiency Upgrades
0
2,000
4,000
6,000
8,000
10,000
12,000
Heating Cooling Water Heating Ventilation Air All Other Loads
Primary Energy Category
An
nu
al C
on
su
mp
tio
n (
kW
h)
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
110%
120%
Pe
rce
nt
Re
du
cti
on
in U
se
Base House Net-Zero Design Reduction in Use
12
Example ZEH Energy UseBaltimore, MD
PV System 5,700 W 500 sqft area Produce 8,266 kWh
Energy End Use
Base House Annual
Consumption (kWh)
Percent of
Total (%)
Net-Zero Annual Consumption
(kWh)
Percent of Total (%)
Heating 12,749 47 2,110 26
Cooling 5,100 19 850 11
Water Heating 3,627 13 167 2
Ventilation Air 0 0 175 2
All Other Loads 5,730 21 4,833 59
Annual Consumption 27,206 100 8,135 100
13
ZEH Approaches
ZEH
Details Involving Builder, Trades, Government, etc.
14
Current ZEH Experience
Over 50% minimum reduction in total energy Typically 50 – 70%
Net-zero electric bill Gas offset unavailable
15
Solar Water Heating System
16
Solar Electric (PV) Systems
Convert sun energy to electricity Operate daily Output varies
PV Systems are Available, Reliable, & Low maintenance Quiet
ZEH remodel in NJ, courtesy of Bill Asdal
17
Utility Connection
18
ZEH Utility Requirements
Utility must “net-meter”: credit for electricity fed back to the utility
Utility must “settle” credit not less than once a year
Utility must be ON to have PV power
Armory Park del SolA Historic Solar Community
John Wesley Miller Companies&
NAHB Research Center
Armory Park del Sol
Urban in-fill Southern Pacific RR executive
homes Existing infrastructure
Downtown Tucson Rio Nuevo Project Walking distance to downtown &
university Cultural activities, arts, & music
Armory Park del Sol
14 acre subdivision Purchased land in 1999 99 lots Construction started 2000
Historic Armory Park/ Armory Park del Sol Designs blend with area Neighborhood embraced
project Increased local property
values
Armory Park del Sol
Single family homes New technology/
construction methods Southwestern design Concrete construction
Thermal mass Metal framing
Termite-proof Significant energy
savings
Armory Park del Sol
Energy efficiency construction Thermal mass Exterior insulation Insulation through slab edge Raised heel truss, R-38 ceiling Dual-pane, Low-E & Low SHGC
windows Ducts in conditioned space 14 SEER heat pump HVAC system design with Manual J Optimized (reduced) duct runs Return air pathway from each room Passive ventilation system
Armory Park del Sol
Solar Electric Technology 1.5 kW Photovoltaic (PV) system minimum Garage roof mount (parapet wall) Utility approved components & systems;
annual utility inspection
Armory Park del Sol
Solar System Attributes One solar subcontractor (The Solar Store) Subsystems & components from major manufacturers
BP PV Modules Trace Inverters
Meets TEP SunShare requirements (ACC approved) Compliance
IEEE National Electric Code TEP Service Requirements Book
Armory Park del Sol
Single family homes Information age design
Minimum 3 telecom ports Digital Satellite Service CAT5e wiring Pre-wired for fiber optics
Security system Central vacuum
Armory Park del Sol
Utility collaboration Tucson Electric Power 5 year A/C guarantee
TEP inspects each home during construction Guarantee qualifies Armory Park del Sol for reduced
residential utility rates Guarantees heating & cooling portion of annual bill
Armory Park del Sol
Utility Collaboration / Solar Electric System State & federal tax credits Homeowner qualifies for TEP cash rebates Output offsets highest Time-of-Use rate TEP inspects solar electric system annually City permit fee credit up to $1,000
Armory Park del Sol
Solar Energy Homes in Downtown Tucson
An Award Winning Community!
SAHBA Builder of the Year, 2003
City of Tucson Most Energy Efficient Builder, 2003
Sonoran Institute Livable Community Award, 2005
NAHB Builder of the Year Award Winner, 2005
Metropolitan Pima Alliance Common Ground Award, 2006
Armory Park del Sol
APdS Standard Homes Predicted to use less than half the energy of a
typical regional home
Armory Park del Sol
John Wesley Miller Companies’ Net Zero Energy Home Project
34
Zero Energy Home Construction
35
Zero Energy Home at APdS
Natural extension of work at APdS
Engineering work funded by DOE through NREL
Goal of net-zero annual energy use
Started with clean sheet of paper
Zero Energy Home Design Team
NAHB Research Center, Inc.Project Management
Design SupportMonitoring
Project SummaryInformation Dissemination
Armory Park Del SolBuild
Define ConstraintsConsumer Education
Solar StoreDesign
Manufacturer ContactSolar Components
ManufacturersDesign Support
Product SpecificationInstallation Requirements
ConsumerInformationFeedback
37
Zero Energy HomeConstruction Features
Concrete walls with 2” polyiso R-41 attic U-0.32, SHGC-0.35 windows SEER 18 AC Combined solar (128 sf) space and water
heating system with tankless backup 4.2 kW PV array PEX piping (with some copper) Fluorescent lighting throughout Outdoor living spaces Ceiling fans without light kits Energy Star appliances
Masonry Walls
2” Polystyrene
Radiant Roof Decking
Window & Porch Overhangs
Air Admittance Valves
Systems in Conditioned Space
4 kW PV System
45
Tucson ZEH at Armory Park del SolMonthly Total Energy Use and Cost
-400
-200
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
Oct
-03
No
v-03
Dec
-03
Jan
-04
Feb
-04
Mar
-04
Ap
r-04
May
-04
Jun
-04
Jul-
04
Au
g-0
4
Sep
-04
Oct
-04
No
v-04
Dec
-04
Jan
-05
Feb
-05
Mar
-05
Ap
r-05
May
-05
Jun
-05
Jul-
05
Au
g-0
5
Sep
-05
Oct
-05
No
v-05
Dec
-05
Jan
-06
Feb
-06
Mar
-06
Ap
r-06
May
-06
Jun
-06
Jul-
06
Au
g-0
6
Ele
ctri
c E
ner
gy,
kW
h;
So
lar
Inso
lati
on
, kW
h/m
2
(+
valu
es =
Ho
use
Use
; -
Val
ues
= U
tilit
y F
eed
bac
k)
-$20
-$10
$0
$10
$20
$30
$40
$50
$60
$70
$80
$90
Mo
nth
ly E
ner
gy
Co
st
Energy Cost Utility Supply PV Supply PV Insolation
Values less than zero indicate sell-back to the utility
Modifications to solar thermal system complete
Now averaging about $10/mo (including $5.28 monthly base fee)
Average 23 kWh/day Total Average Energy Use
John Wesley Miller Companies’ Zero Energy Home (ZEH)
Blower, kWh, 663
A/C Compressor, kWh, 1,847
Demand Water Heater, kWh, 1,040
Other, kWh, 3,536
Refrigerator, kWh, 631
Lights, kWh, 651
Data from 9/1/05 to 8/31/06
Utility Supply,
kWh, 1158, 14%
PV Supply,
kWh, 7209, 86%
Tucson ZEHZEH End Uses
ZEH 1st Year Monitoring
ZEH Occupied Period Monitoring
ZEH Monitoring Results
Year 1 ZEH Monitoring Results
ZEH Monitoring ResultsInverter-Demand Heater
Compatibility
ZEH Monitoring ResultsPV System Output
54
Plug Loads
The big challenge…
55
Energy Simulation Summary
Description
Annual Electrical Consumption
Cooling Heating Fan DHW Lighting Appl/Othr Total
(kWh/yr) (kWh/yr) (kWh/yr) (kWh/yr) (kWh/yr) (kWh/yr) (kWh/yr)
JWM Standard * 3,568 621 772 1,855 1,873 3,687 12,376
ZEH As-Built ** 2,207 200 430 158 779 3,072 6,846
Tucson Standard*** 6,770 669 1,229 4,064 1,873 3,687 18,292
*(includes passive SDHW)**(Option A+B+C+D+E w/ R41 ceiling instead of R43)***Light Frame, R19 ceiling, 10 SEER, double pane wood frame windows
Occupied Use To Date :
Demand Heater = 1,918 kWh, Lighting = 640 kWh, Other = 3,116 kWh
Total Use to Date = 6,406 kWh (26.3 kWh/day)
Estimated Daily = 18.8 kWh
56
ZEH Lessons Learned
Project Success, Builder interest PV system
Utility interest prime Knowledgeable installer Inverter compatibility problems (new)
Solar Aesthetics Even with flat roofs
Solar thermal system performance Temperature limitations Controller Losses
57
ZEH Lessons Learned
Integration of HVAC & thermal system Simple design/connections
Space and access for thermal storage Thermal mass
Winter penalties? Air admittance valves
Manufacturer design required Plumber reticence Work
58
ZEH Lessons Learned
PEX plumbing Design is important Different installation
method Lighting
Whole-house permanent fluorescent lighting options NOT mainstream
New technologies emerging (LED, etc)
Plug loads still need control
ZEH2 Utility Savings Estimate PV system cost benefit offsets utility-supplied energy
John Wesley Miller Companies’ Zero Energy Home 2 (ZEH2)
ZEH2 Energy Features Tucson, AZ
Concrete Block Construction
Foundation 12” floating slab
Exterior Insulation 2” exterior insulation (R-13) Attached using z-strips
Ceiling & Roof Insulation R-38 ceiling insulation 1” rigid foam on roof deck
(R-6.5)
ZEH2 Energy Features(cont.)
High Efficiency Space Heating and Cooling Heat Pump: Trane XL19i Two-stage compressor Variable speed blower Sealed ducts in conditioned
space (22 CFM25 – total) Mechanical Ventilation
Mechanical room exhaust fan Fresh air to central return
Solar Hot Water Preheat System Closed loop 80G storage 64sf collector
Tankless Backup Water Heater
Manifold Distribution System
ZEH2 Energy Features (cont.)
ZEH2 Energy Features (cont.)
Efficient Windows U-value: 0.35, SHGC: 0.30
Air Sealing Package 740 CFM50
Lighting 90% Hard-wired fluorescent lighting ENERGY STAR fixtures CFL
Appliances ENERGY STAR Refrigerator,
Dishwasher, Washing Machine
Solar Electric PV System 6.93 kW (DC) PV
System Net Metered > 100%
Predicted Energy Savings with PV
ZEH2 Energy Features(cont.)
Code Approval & Programs
Meets all safety, health, and 2006 IBC & 2006 IECC code requirements
Tucson Electric Power’s (TEP’s) Guarantee program 5 year heating/cooling & comfort
Tucson Sustainable Energy Standard Performs 50% better than the Model
Energy Code Builders Challenge Builder Federal Tax Credit Local & State Tax Incentives
Quality Control RequirementsHigh Performance Home Specifications
Envelope Moisture Control
Foundation drainage/capillary breaks – n/a slab design
Climate appropriate vapor retarder – n/a due to climate & masonry wall construction
Continuous drainage plane – felt paper over fixed polyisocyanurate
Envelope Air Tightness
740 CFM50
Space Conditioning
Equipment and duct sizing per ACCA methodology
Space Conditioning (cont.)
Distributed whole house mechanical ventilation – exhaust fan and a central fan integrated supply
Local exhaust – bathrooms, kitchen
Filtration – Honeywell electronic air cleaner
Sealed ducts in conditioned space
No combustion appliances or fireplace
System capable of maintaining RH < 60%
Hot Water
SRCC rated collectors for solar hot water system
Quality Control Requirements High Performance Home Specifications
Neutral Cost Target
Upgrade Costs
Neutral Cost Target Efficiency Feature Upgrades
Note: PV not included
Neutral Cost Target Tax Credits & Incentives
Neutral Cost Target Efficiency Feature Upgrades w/ PV
Note: PV incentives not included for Std Home
Neutral Cost Target Efficiency Feature Upgrades w/ PV
Note: PV incentives included for Std Home
74
Value of ZEH
ZEH2 Conclusions
APdS demonstrates increasing levels of energy efficiency
ZEH is possible Technologies “off-the-shelf,”
Attention to builder’s marketing effort is necessary Builders Challenge
Green Building
Local Utility Programs
ZEH1 MonitoringWhole House Energy Comparison – ZEH
ZEH2 MonitoringWhole House Energy Comparison – ZEH2
78
Incentives
Federal Incentives
Tax Credit: 30% of cost with no upper limit
Expires: December 31, 2016
Details: Existing homes & new construction Principal residences & second homes Rentals do not qualify
79NEXUS EnergyHomes
80
Incentive Details
Solar Water Heat Certified by SRCC or equivalent a Must provide ≥ 50% dwelling’s water heating Not apply to swimming pools/hot tub
Photovoltaics Wind Fuel Cells
$500 per 0.5 kW maximum Geothermal Heat Pumps
Meet federal Energy Star criteria
81
Solar Renewable Energy Certificates (SRECs)
In SREC states, Renewable Portfolio Standard (RPS) requires some electricity from solar
The SREC program provides a means for SRECs to be created for every megawatt-hour of solar electricity created. 1 SREC = 1,000 kWh of solar electricity = 1
MWh of solar electricity 10 kW solar capacity = ~12 SRECs per year
Maryland SREC Market
Energy Year Jan 1 - Dec 31
SREC Useful Life 3 years
Solar Requirement Reaching 2% of total elec generated in 2021
Solar Alternative Compliance Payment (SACP) $400 through 2014
82
83
84
Summary
ZEH used to be all about cost Still an interest in ZEH, driven by
Increasing utility costs Lower cost of PV Familiarity (owners & trades)
Consumer acceptance Utility acceptance New financing mechanisms
Changing accessibility
85
Programs Energy Efficiency Certification
ENERGY STAR DOE Challenge Home
Energy Efficiency Research & Development Building America Program
Green Certification National Green Building Certification Program
Awards
References
NAHB Research Center Technical Website www.toolbase.org
DOE Energy Information Administration (EIA) www.eia.gov
DOE/EERE Buildings Energy Data Book http://buildingsdatabook.eren.doe.gov/default.aspx
ENERGY STAR www.energystar.gov
Database of State Incentives for Renewables & Efficiency (DSIRE) www.dsireusa.org
86
87
Questions?
Driving Innovation in Housing Technology
Thank You!
Amber Wood
NAHB Research Center
Manager, Energy Programs
400 Prince George’s Blvd Upper Marlboro, MD 20774(direct) 301.430.6309 (fax) 301.430.6180
www.nahbrc.com