Energy Efficiency/Weatherization – New Technologies

Frank Rapley, General ManagerTVA Efficiency Program DesignRegional Marketing, Member Services & Communications ConferenceSavannah, Georgia

March 30, 2010

TVA NEAR ZERO ENERGY HIGH PERFORMANCE HOMES RESEARCH PROJECT

Today’s Discussion

TVA Campbell Creek Research Project Project Scope Simulated Occupancy Test Home Overview

High Performance Home Features House 1 – Builder House House 2 – Retrofit House House 3 – Near Zero-Energy House

Monitoring and Occupancy Simulation Evaluation

Key Takeaways

Overview

TVA built three experimental homes at Campbell Creek in East Tennessee to evaluate the effectiveness of residential construction and efficiency technologies in a controlled environment

TVA and its partners, Oak Ridge National Laboratory (ORNL) and EPRI, will be evaluating over the next few years:

residential building techniques energy efficiency technologies demand response concepts consumer energy-use behaviors

TVA will use the results to develop the best, most cost-effective residential energy efficiency and demand-response tools to educate builders, developers and consumers

Project Scope

Construction began in FY 2008

Three houses completed and turned over to TVA at the beginning of 2009 calendar year:

Builder House Retrofit House Near Zero-Energy House

Simulated occupancy started June 2009

Over 300 sensors and measurements in the houses

Simulated OccupancyDone automatically by installed control systems

All thermostats set same (no setback)

Lights on and off

Run dishwashers on schedule

Run clothes washer and dryer on schedule

Activate showers on schedule

Open and close refrigerator and freezer doors

Human emulator (latent generator – in progress)

Electric resistance heaters to simulate other internal electrical loads

Energy-Efficient Test Homes

Net Monthly Energy Use*

Standard House 1,738 kWh

Retrofit House 1,377 kWh

Advanced House** 795 kWh

*Average net consumption July 09 – Jan 10**Includes reduction by solar generation

Monthly Energy Cost*

Standard House $146.60

Retrofit House $117.56

Advanced House $40.06

*Average cost July 2009 – Jan. 2010Using Local Utility’s Residential Rates and TVA Generation Partners Solar Credit on Advanced House

House 1: Builder House (HERS 85)TVA Near Zero Energy High Performance Homes

Cost: $250,000 This house represents a typical house (2,400 square feet) currently

built in the Tennessee Valley and serves as a control against which the other homes are compared

Incorporates local building codes and standards and is projected to use slightly less energy than a new house built to the 2006 International Energy Conservation Code (IECC)

“All electric” upgrade

Two SEER 13 heat pumps total 4.5 tons

5.7 Air Change per Hour (ACH) @ 50 Pascal

House 1 – Builder House (HERS 85)

House 2: Retrofit House (HERS 66)TVA Near Zero Energy High Performance Homes

Cost: +$10,000 from base house for retrofits described below

Same construction as House 1 (Builder House), but retrofitted with energy efficiency technologies that an existing homeowner could add to improve efficiency

Major retrofits include: low-e, gas-filled windows; sealed, insulated attic; 100% CFL; smaller (3 ton versus 4 ton), higher SEER (16 versus 13) heat pump; and heat pump water heater

Projected to use two-thirds of the energy of a new house built to code

Blower door test -

3.4 ACH at 50 Pascal

House 2 – Retrofit House – HERS 66

House 2 – Retrofit House – HERS 66Envelope

Slab construction - with 1’ X 24” perimeter insulation

High performance windows U-value of 0.34 and SHGC of 0.33

Windows installed with panned flashing and weather-lapped flashing tapes

Window sash replacement to lower U values and SHGC

Attic cathederalized with spray foam and spray Fiberglas and sealed (i.e. becomes conditioned space.)

Whole house air tightening package and addition of mechanical ventilation (one or both supply ventilation with bath exhaust)

Sealing/insulating knee walls in the bonus room

Ducts inside the conditioned space

House 2 – Retrofit House – HERS 66Technologies

HVAC

One 3 ton SEER 16 heat pump with ECM indoor fan motors and zone dampers

Kitchen exhaust fan ducted to the outside Duct sealing Ducts located in sealed (semi-conditioned) attic

Electrical

Energy efficient lighting fixtures with 100% fluorescent Energy Star appliances High efficiency office vs. lower efficiency High efficiency entertainment center vs. lower efficiency

Plumbing

Heat Pump Water Heater

House 2: Heat Pump in Cathedralized Attic

House 2: Hybrid – Heat Pump Water Heater

House 3: NZEH – Big Step House (HERS 32)TVA Near Zero Energy High Performance Homes

Cost: +$35,000 from base house including PV without any incentives

Built using the latest in construction technologies to make it as efficient as possible and still provide excellent curb appeal

Home characteristics include: triple pane windows; R-48 spray fiberglass ceiling insulation; single HVAC system (2 ton), SEER 16 heat pump; 100% CFL; and Energy Star appliances

Employs photovoltaic panels and solar water heating to help make it anear zero-energy house

Projected to use one-third the energy of a "code“ house

Blower door test - 2.4 ACH @ 50 Pascal

House 3: NZEH – Big Step House – HERS 32

House 3: NZEH – Big Step House – HERS 32Envelope

2 X 6 Advanced framing air tight construction using flash (foam) and sprayed spider (fiberglass) and structural insulating sheathing with taped seams

High performance triple pane windows U-value of 0.12 andSHGC of 0.30

Windows installed with panned flashing and weather-lappedflashing tapes

Slab perimeter insulated with 2 inch foam

R-48 spray fiberglass ceiling insulation (conventional vented attic) and radiant barrier on roof deck

House 3: Structural Insulated Sheathing

House 3: Spray Foam Adds R-Value and Air Barrier

House 3: NZEH – Big Step House – HERS 32 Technologies

HVAC

Single HVAC system (2 ton) SEER 16 heat pump with ECM fan motor and variable speed compressor. System has zone dampers serving both floors

Ducts and indoor coil inside the conditioned space

Transfer ducts in each bedroom

Mechanical ventilation with a motorized damper connected to the central air distribution system and controlled with an energy recovery ventilator exhausting three baths and kitchen, and supplying the three bedrooms and great room

The supply outlets positioned at high interior walls aimed toward the exterior walls in each room

House 3: NZEH – Big Step House – HERS 32Technologies

Electrical and Appliances House will be wired with three kill switches, entertainment system, home office

and whole house, with ORNL Feed back meter will be wired into the house showing in the kitchen the whole

house energy consumption real time Energy efficient lighting fixtures with 100% fluorescent Energy Star appliances Photovoltaics - 2.5 kW of PV is installed on the roof. The system is grid

connected through TVA Generation Partners program

Plumbing Drainback solar domestic water heating system is installed Heat recovery from grey water* Heat recovery from dryer vent* Heat recovery from dishwasher*

House 3: Solar Drainback Tank

House 3: Solar Storage Tank and HEX

House 3: Robo Refrigerator

House 3: PVs and Solar Water Heating

Monitoring and Occupancy SimulationTVA Near Zero Energy High Performance Homes

Monitoring and Occupancy Program

Limited winter 2008-09 data

Full monitoring and occupancy simulation started June 1, 2009

ORNL and EPRI working on the simulation details

Blower door tests

House 1 – 5.7 ACH @ 50 Pascal

House 2 – 3.4 ACH @ 50 Pascal

House 2 – 2.4 ACH @ 50 Pascal

Electric Bills July 2009 – January 2010

Builder Retrofit nZEH $-

$50.00

$100.00

$150.00

$200.00

$250.00

$133.78

$100.07

$43.02

$152.44

$110.78

$20.35

$119.06

$81.41

$29.55

$120.29

$134.35

$12.37

$175.90

$148.82

$68.53

$216.19

$164.57

$82.59

$146.60

$117.56

$40.06

7/29/09

8/31/09

9/28/09

10/28/09

12/1/09

12/31/09

1/28/10

Avg

kWh Usage July 2009 – January 2010

Builder Retrofit nZeh0

500

1000

1500

2000

2500

3000

1512

1109

922

1735

1237

684

1336

886

606

1237

924

547

1398

1572

477

2186

1835

1046

2760

2078

1285

1738

1377

795

7/29/09

8/31/09

9/28/09

10/28/09

12/1/09

12/31/09

1/28/10

Avg

Solar Generation Summary

Solar Generaion kWH - nZEH0

50

100

150

200

250

300

350

400

345

368

237 234

279

162

183

258 Jul-09

Aug-09

Sep-09

Oct-09

Nov-09

Dec-09

Jan-10

Avg

Generation Partners Solar Credit

Solar GP Credit $-

$10.00

$20.00

$30.00

$40.00

$50.00

$60.00

$70.00

$80.00

70.2627

74.94688

48.26742

47.23758

56.03157

31.93506

35.8112699999999

52.0703542857143Jul-09Aug-09Sep-09Oct-09Nov-09Dec-09Jan-10avg

Builder House Energy Breakdown - January 2010

1,176.4

822.3

333.5

87.3

36.223.2

4.5

49.0161.6

231.1

H1 Total (kWh)

HP1 HP2

WH Dryer

Fridge DishW

Wash Range

Lights Plugs

Retrofit House Energy Breakdown - January 2010

1,485.6

235.9

72.4

30.4

27.9

7.9

8.5

66.8

211.6

H2 Total (kWh)

HP1 HP2 WH

Dryer Fridge DishW

Wash Range Lights

Plugs

NZEH Energy Breakdown - January 2010

1,089.4

24.0

65.9

31.8

34.68.610.4

59.0219.2

H3 Total (kWh)

HP1 HP2 WH

Dryer Fridge DishW

Wash Range Lights

Plugs

Key Takeaways

While data is still be collected for the first year, information suggests making sure you have a good air barrier on a house is key, in particular:

Ducts inside the conditioned space 2 X 6 advanced framing ensures air tight construction Utilizing flash (foam) and sprayed spider (fiberglass) For new construction, consider having houses solar ready (proper

orientation, etc.)

Possible modifications being considered for next year (FY 2011) include: House 3: Considering geothermal system change out House 2: Considering change to variable refrigerant flow heat

pump in air conditioned space (ductless) House 1: Will remain as control house Also will look more at demand response activities

An interim report on the TVA energy efficiency homes research project to be released Summer 2010

QuestionsDavid Dinse

Project Manager, Environment and TechnologyTennessee Valley Authority

(423) 751-7410drdinse@tva.gov