Low E Storm Windows for Weatherization Not the Same Old Storm Windows Anymore It is Time for a Fresh Look Public Service of Colorado Ponnequin Wind Farm 2011 National Weatherization i Training Conference December 2011 Marc LaFrance 1 Low-E Storm Windows for Weatherization eere.energy.gov 1
Session Outline Opening Slides (Marc LaFrance, DOE Building Technologies Program) Introduction to Low-E Storm Window Technology (Tom Culp, Birch Point Consulting) Case Study Demonstrations (Craig Drumheller, NAHB Research Center) NEAT Analysis for Low-E Storm Windows and Pennsylvania Weatherization Program (Tom Culp, Birch Point Consulting) 2 Low-E Storm Windows for Weatherization eere.energy.gov 2
Not the Same Old Windows History Weatherization agencies have sometimes inst alled window measures that t are not cost effective thus window retrofits are not always seen as favorable New Technology Low e storm windows use existing technology (durable low e coatings that have been around for around two decades) but in a new application that can be very cost effective R 5 or 0.2 U value windows (triple pane or 4 th surface low e double pane products) have lower price points and when a window must be replace for structural or health and safety issues, can be installed instead of typical double pane low e windows IT IS TIME TO TAKE A NEW LOOK AT WINDOWS 3 Low-E Storm Windows for Weatherization eere.energy.gov 3
Key Partners Major demonstration Chicago Weatherization NAHB Research Center, Lawrence Berkeley National Laboratory, Community and Economic Development Association of Cook County (CEDA), Arkema, HUD, DOE Pennsylvania Pilot Program PA State, LBNL, Energetics, Quanta Technologies, DOE ARRA Warm Climate Residential Demonstration and Cold Climate Commercial Demonstration ti - Quanta Technologies, DOE (still in progress) 4 Low-E Storm Windows for Weatherization eere.energy.gov 4
Weatherization Analysis by DOE Emerging Technology Team Using RESFEN and NEAT to Support Weatherization Pennsylvania has shown significant interest in window retrofits, accelerating the adoption of energy efficiency window systems into its Weatherization Assistance Program. Lawrence Berkeley National Laboratory (LBNL) and Energetics Incorporated provided detailed analyses using the RESFEN and NEAT (ORNL approved weatherization tool) programs. Analyses include upgrading all single pane and metal framed clear double pane windows with low-e storm windows and updating to an R-5 window when a window must be replaced due to health, safety or structural concerns (Analyses derived a maximum average incremental cost of $8.90 per ft2 when using an R-5 window in this scenario). Price points were also derived for the replacement of an existing single pane wood frame or metal frame clear double pane window with an R-5 window. 5 Low-E Storm Windows for Weatherization eere.energy.gov 5
Weatherization Analysis Pennsylvania climate and energy prices State Heating Degree Days (HDD) Divisions Weighted by 2000 Population thru April 2010 (Base Temperature 65 Degrees F) Pennsylvania: 5968 Based on NOAA (http://lwf.ncdc.noaa.gov/oa/documentlibrary/hcs/hcs.html) Pennsylvania Philadelphia Harrisburg Pittsburgh Scranton HDD 4759 5201 5829 6291 http://www.worldclimate.com/cgi-bin/data.pl?ref=n41w075+1306+369705c http://www.nrcc.cornell.edu/ccd/nrmhdd.html Energy Prices Natural Gas Electricity Pennsylvania $1.34/therm $0.12/kWh Based on www.windowsvolumepurchase.org R-5 Savings Estimator Tool 3- year average 6 Low-E Storm Windows for Weatherization eere.energy.gov 6
Weatherization Analysis Results: Low-E Storm Windows Parameters Same pricing as the LBNL analysis (average $7.85 per ft2, plus $15 per window for other installation costs) across Scranton, Harrisburg, Philadelphia and Pittsburgh Glass emissivity = 0.22 Center-of-glass SHGC = 0.74 15 year lifetime Both furnace efficiencies of 94.7% and 80% Natural Gas Heating For all cases in 37 homes modeled across four cities, low-e storm windows were selected as a qualified measure with SIR values substantially higher than 1. SIR values over single pane wood frame windows with a furnace at 80% efficiency ranged from 1.4 to 2.2, with an average of 1.7. SIR values over metal frame clear double pane windows with a furnace at 80% efficiency ranged from 1.3 to 2.1, with an average value of 1.6. 7 Low-E Storm Windows for Weatherization eere.energy.gov 7
Weatherization Analysis Results: R-5 Windows Parameters for replacing a degradedd d window with an R-5 wind ow $5 incremental cost over a basic code window across Scranton, Harrisburg, Philadelphia and Pittsburgh, 94.7% Furnace Efficiency, Natural Gas Heating, 20 year lifetime U-factor = 0.22, SHGC = 0.3 For all cases in 37 homes modeled across four cities, R-5 windows were selected as a qualified measure with SIR values substantially higher than 1. SIR values ranged from 1.6 to 3.0. Price Point for SIR of 1 and upgrade to R-5 Windows over Single Pane Wood Frame Windows for worst case homes City Scranton Harrisburg Pittsburgh Philadelphia Installed Window Cost $/ft2 $26.45 $22.35 $25.55 $25.15 Price Point for SIR of 1 and upgrade to R-5 Windows over Metal Frame Double Clear Pane Windows for worst case homes City Scranton Harrisburg Pittsburgh Philadelphia Installed Window Cost $/ft2 $25.45 $21.50 $24.55 $24.35 8 Low-E Storm Windows for Weatherization eere.energy.gov 8
Contact Information P Marc LaFrance, CEM Technology Development Manager Building Technologies Program Office of Energy Efficiency and Renewable Energy US Department of Energy marc.lafrance@ee.doe.gov 1-202-586-9142 Fax 1-202-586-4617 www.eere.doe.gov www.eereblogs.energy.gov/buildingenvelope energy gov/buildingenvelope 9 Low-E Storm Windows for Weatherization eere.energy.gov 9