TVA Near Zero Energy High Performance Homes Research Project Energy Efficiency/Weatherization – New Technologies TVA Near Zero Energy High Performance Homes Research Project March 30, 2010 Frank Rapley, General Manager TVA Efficiency Program Design Regional Marketing, Member Services & Communications Conference Savannah, Georgia

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 Occupancy Done 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. 2010 Using Local Utility’s Residential Rates and TVA Generation Partners Solar Credit on Advanced House Three houses built for comparison with same square feet automated to replicate family of four. House 1 (Builder House) Cost: $250,000 This house represents a typical house (2,400 sq ft) currently built in the Tennessee Valley. It incorporates local building codes and standards and serves as a control against which the other homes are compared. House 2 (Retrofit House) Cost: +$10,000 for retrofits described below Same construction as House 1, but retrofitted with energy efficiency technologies that an existing homeowner could add. 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. House 3 (Near Zero Energy House) Cost: +$35,000 from base house including PV without any incentives Built using more advanced construction technologies to make it as efficient as possible. Home characteristics include: 2.5 kW photovoltaic panels; solar water heating; 2X6 advanced framing; air tight construction; triple pane windows; R-48 spray fiberglass ceiling insulation; single HVAC system (2 ton), SEER 16 heat pump; 100% CFL; and Energy Star appliances.

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

House 1 – Builder House (HERS 85) 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 2: Retrofit House (HERS 66) TVA Near Zero Energy High Performance Homes House 2: Retrofit House (HERS 66)

House 2 – Retrofit House – HERS 66 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 Envelope 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 66 Technologies 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 House 3: NZEH – Big Step House (HERS 32)

House 3: NZEH – Big Step House – HERS 32 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 a near 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 Envelope 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 and SHGC of 0.30 Windows installed with panned flashing and weather-lapped flashing 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 32 Technologies 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 When water drains it goes into tank when its not pumped.

House 3: Robo Refrigerator

House 3: PVs and Solar Water Heating

Monitoring and Occupancy Simulation TVA Near Zero Energy High Performance Homes Monitoring and Occupancy Simulation

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

kWh Usage July 2009 – January 2010

Solar Generation Summary

Generation Partners Solar Credit

Builder House Energy Breakdown - January 2010

Retrofit House Energy Breakdown - January 2010

NZEH Energy Breakdown - January 2010

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 -Also consider having houses solar ready (i.e. proper orientation - within 20 degrees of due south, etc.)

Questions David Dinse Project Manager, Environment and Technology Tennessee Valley Authority (423) 751-7410 drdinse@tva.gov