Energy and the Architectural Fenestration Industry

Transcription

1 1 Energy and the Architectural Fenestration Industry

2 2 This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services may be addressed at the conclusion of this presentation.

3 3 This presentation is protected by U.S. and International copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. American Architectural Manufacturers Association 2012

4 4 Introduction The fenestration industry has been focused on energy savings and building performance since WWII Manufacturers, architects and specifiers, owners and developers are learning more about and taking initiative to focus on conserving energy, thus moving toward green products

5 AAMA/WDMA U.S. Industry Market Study 2009 (Millions of Square Feet) Types of Commercial Framing Materials Framing Type Aluminum, with thermal break Aluminum, w/out thermal break Curtainwall Storefront Site Fabricated Windows Shop Fabricated Windows Overall Percentage Percentage Percentage Percentage Percentage 60% 28% 45% 50% 48% 40% 71% 55% 8% 43% Wood Vinyl, Other Total _ 1% _ 19% 4% _ 23% 5% 100% 100% 100% 100% 100%

6 6 Description Considering the building envelope The national priority and goals Understanding the types of energy loss Impact of fenestration on energy loss How to minimize energy loss Design considerations for fenestration Embrace change

7 7 Learning Objectives Considering the building envelope The national priority and goals Understanding the types of energy loss Impact of fenestration on energy loss How to minimize energy loss Design considerations for fenestration Embrace change

8 8 Overview Energy conservation is everyone s responsibility Saving energy is being green Education is the key Saving energy reduces carbon emissions Ultimate goal is Zero Energy Buildings

9 9 Building as the Integrator Efficiency Technologies & Building Integration Fuel Cell, Hydrogen Infrastructure, Plug in Hybrids Building Technologies Zero Energy Solar Buildings Goal Distributed Transportation Energy PV and Solar Hot Water Technologies Combined Heat and Power Technologies

10 Building Energy Consumption 10 and Envelope Relationship * Source: U.S. Department of Energy

11 11 Why Buildings? Consume 40% of our nation s energy* Consume 50% of all electrical energy DOE's target was to reduce energy usage in buildings by 50% by the year % in new buildings; 20% in existing buildings Current strategic goal to create technologies and design approaches that enable net-zero energy buildings New requirement would reduce energy efficiency by 60-70% than conventional practices *Source: Department of Energy (DOE)

12 12 Energy Policy Act of 1992/2005 Reduce energy consumption by 50% Reduce greenhouse gases by 17% by 2020 Develop renewable energy resources Create mandatory energy codes ASHRAE 90.1 (basis of design) Includes residential and commercial EPA 2005 requires savings of 3% per year One gallon of gasoline=115,000 BTU=5 lbs of carbon *Source: Department of Energy (DOE)

13 13 DOE Savings Goals* Measured in Quads 1 Quad = Quadrillion BTUs* = 8 billion gallons of gasoline 2 Quads Per Year By Quads Per Year By 2020 Zero Energy Building (ZEB) by 2030 Potential energy savings for buildings by 2030 is $160 billion per McKinsey & Company *DOE Energy Efficiency and Renewable Energy (EERE)

14 Daylighting, Solar Control and Energy Conservation in Buildings The average age of all commercial buildings in the U.S. is 30.5 years, many with inefficient fenestration, HVAC and lighting. 14

15 15 Energy Savings from High- Performing Fenestration U.S. commercial construction market million sq ft of vision area DOE goal for building energy savings Potential energy savings using current technology

16 16 Types of Energy Loss Energy loss in the fenestration industry is about heat gain and heat loss Heat transfer Light/solar heat gain Air infiltration

17 17 Heat Transfer What is it? Hot Body Heat transfer is the passage of thermal energy from a hot body to a cold body Heat transfer can never be stopped; it can only be slowed down, it always goes from hot to cold Cold Body

18 18 Heat Transfer Three Types Convection Conduction Radiation Air Infiltration

19 19 Convection Convection in the most general terms refers to the movement of currents within fluids or gases In short, warmer low density gases are rising above cooler more dense air

20 20 Conduction Heat conduction or thermal conduction is the transfer of thermal energy, from higher temperature to lower temperature Transfers heat through the frame, glass, and air space between the glazing layers Energy transfers from the warmer side to the cooler side

21 21 Radiation Thermal radiation is electromagnetic radiation emitted from the surface of an object which is due to the object's temperature Inward and outward acting energy sources Inward: solar energy Outward: indoor heat

22 22 Air Infiltration Air Infiltration is an important part of the energy performance of a window. Inadequate gaskets, poor fitting sash to frame members, and loose locking hardware can decrease the energy performance of a window. Air infiltration through new windows is reduced to negligible

23 23 Measuring Heat Transfer Heat transfer of a fenestration product is indicated by the U-factor (U-value) given to the product by testing for the rate of heat flow through the product Standard for quantifying the insulating value of a product Measured in: W/m2- C or BTU/hr-ft2- F

24 24 How To Minimize Energy Loss? Insulating glass Frames with a Thermal Barrier Minimize Condensation

25 25 How To Minimize Energy Loss? Select the appropriate products Advancements in fenestration products Using design features to minimize heat loss and heat gain Non- Thermal Thermal barrier Pour and Debridged Thermal barrier Polyamide Strips

26 26 Solar Heat Gain Coefficient (SHGC) Measurement given to glazing indicating how well the sun s energy is blocked SHGC is expressed as a dimensionless number from 0 to 1.0 The higher the number, the more the solar gain

27 27 Solar Energy and Glass Reflected Radiation EXTERIOR INTERIOR Absorbed radiation Three things happen to solar radiation as it passes through a glazing material: Transmission Reflection Absorption Inward flowing component of absorbed radiation

28 28 Solar Energy Effects - Glass New technology makes it possible to manipulate the proportion of transmittance, reflectance, and absorption for different wavelengths Much of the recent innovation in glass for fenestration products has been focused on controlling solar radiation to improve energy performance

29 29 Visible Light Transmittance (VT) Visible light transmittance is an optical property given to glass Influenced by: Glazing type Number of glazing layers Coatings applied

30 30 The Future of High-Performing Fenestration Major Components: Frame and thermal barrier Glass and spacer Glass coatings Daylighting

31 Market Trends, Forces 31 and Drivers Rising cost of electricity and natural gas Movement toward CO 2 cap and trade Tougher energy codes LEED and green building Changing attitude of government, DOE Property values beginning to be influenced by building s energy use

32 32 Increasing Call for Better Thermal Performance DOE has a long term goal of Net Zero Energy Use: Carbon Footprint impact is increasingly important globally Lower energy costs = higher occupancy rates, higher lease rates, higher return upon property sale Energy certificates are increasing in use for buildings Mandatory codes or incentives by ENERGY STAR /IECC/local codes

33 Energy Codes 33 Getting Tougher 36 states have adopted IECC or equivalent 2012 IECC commercial U-factors: Fixed windows range of 0.29 (zones 7-8) to 0.50 (zone 1-2) Operable windows range of 0.37 (zones 7-8) to 0.65 (zone 1-2) No distinction in maximum permitted U-factor based upon framing type. DOE and others are calling for tougher codes

34 34 Commercial State Energy Code Status AS OF SEPTEMBER 1, 2011 Image found at:

35 35 Aluminum Framing System Aluminum framing supports large glass spans Strength-to-weight ratio of aluminum handles this weight with ease Maximizing glass surfaces allows for natural daylighting Low maintenance Recyclability

36 Thermal Barrier System Main function: To separate an aluminum profile into two parts to reduce thermal conductivity in a window using polyamide insulating strips, poured and de-bridged polyurethane, or other low conductance materials. Conductivity values of materials Aluminum: 92.4 BTU/hr-ft-F Thermal Barrier: 0.3 or less BTU/hr-ft-F

37 Hybrid PVC Framing Systems Strong and durable Energy efficient Meet the needs of high-rise fenestration Large openings possible Wide range of color options Cost effective Low Maintenance

38 Hybrid PVC Framing Systems Thicker outer walls Multiple weatherseals Hybrid, steelreinforced PVC framing for strength and stability Multiple insulating air chambers for very low frame U-factors

39 Pultruded Fiberglass Framing System Properties of pultruded profiles Highly insulative/low conductivity High condensation resistance Helps achieve increased thermal comfort

40 Pultruded Fiberglass For Commercial Application High strength pultruded composite framing profiles Pultruded screw bosses for strong connections Glazing pockets for IG thicknesses up to 1 1/2 Pultruded gasket groove to accommodate glazing gaskets Pultruded pressure plate

41 41 Recyclability of Framing Materials Recyclability is an important part of the building and design process Reference other AAMA courses and the AAMA website for more information

42 42 Product Selection Balancing energy, space, daylighting and comfort: Select U-Factor based on energy requirements Select SHGC based on building orientation and location Select day lighting requirements to reduce interior lighting loads Select visible light transmittance for occupant comfort Select spectral glass as needed

43 Daylighting Benefits Energy Savings Increased Productivity Higher Test Score in Education Settings Higher Retail Sales Improved Patient Comfort

44 44 Glazing Improvements in Glass Glass industry has advanced tremendously over the last several years: Low-E Low solar Spectral coatings Selective custom coatings Films/tinting applied to glass

45 45 Solar Energy Effects - Glass Glass types are compared and selected by the following criteria: Visible Light Transmittance (VT) Solar Heat Gain Coefficient (SHGC) Emissivity U-factor for center of glass (U COG )

46 46 Glazing Improvements Multiple Layers (IG) Select exterior and interior lites Inert gases Laminates Spacers Warm edge Diffused light panels Triple and quadruple glazing Suspended films Dynamic glazing

47 Insulating Glass (IG) Spacer Technology High-performance warm edge (much lower conductivity) Warmer edge spacers (lower conductivity) Traditional aluminum IG spacer

48 48 Benefits of High-Performance Warm Edge Spacer Energy savings/ Environmental impact Improved overall system U-factor Higher sightline temperatures improves condensation resistance Improved sound control (OITC/STC)

49 49 Thermal Imaging of Higher Performing Insulating Glass Dual, Clear, Alum. spacer Dual, Clear, warm-edge Dual, low-e, warm-edge Dual, low-e with Argon, warm-edge -6.0 C 20 C

50 Improving U-factors with Technology 50 F Glass Type Clear/clear Clear/low-E Clear/low-E Thermal Barrier non-thermal Standard Thermal Barrier Enhanced Thermal Barrier Spacer Aluminum Stainless Steel Warm Edge U-Factor (BTU/hr-ft²- F) CRF Sightline Temp 24.1 F 38.7 F 47.8 F

51 51 What s Next for Lower U-factors? Framing systems Finishes / coatings that reduce thermal conductivity New thermal barrier materials/designs New composite framing materials Dynamically modeled frame designs that optimize both thermal and structural perfomance

52 What s Next for 52 Lower U-factors? Glass Multiple coatings and airspaces Dynamic Coatings Improved efficiencies for converting sunlight to useable energy Warm edge spacer designs and materials

53 53 Future for Window and Facades Next generation window highly insulating and dynamic Integrated commercial façade systems PV solar facades, opaque and transparent Prototype Concept Window (Highly Insulating & dynamic) Integrated PV Glazing

54 54 Dynamic Window Field Trials Commercial Project Results Cooling energy savings up to 25-40% Peak demand savings up to 26% SHG reduction up to 65% Energy savings up to 20% 54

55 55 Growing Trends Sun shades and light shelves Triple glazing and multiple coatings Future developments Building Integrated Photovoltaic Glass (BIPV) Dynamic glazing Electrochromic glass Photochromic and Thermochromic

56 Sun Shades and Light Shelves Sun Shades: Exterior shading devices designed to provide an economical solution for reducing solar heat gain and glare while allowing natural daylight into the building Light Shelves: Horizontal devices installed onto the interior of a window opening to redirect and redistribute natural light into the interior space of the building

57 Application Considerations The effect of shading devices on solar heat gain will depend on several things Key factors to consider : Building orientation Climate Sun angles Blade types Projection depths ISU Administration Ames, IA

58 Application Considerations Climate - most effective for relatively clear climates Latitude - most effective at mid-latitudes Orientation - most effective for South facing façades Depth - should be roughly equal to the height of the clerestory window above the shelf Finishes - bright white paint or clear anodized finishes for the top surface will maximize performance Graphic: Tips for Daylighting, LBNL, 1997

59 Skylight/Sloped Glazing 59 Additional Information This course provides an overview of energy for commercial applications with primary emphasis on wall mounted fenestration products (windows, doors and curtain wall) More specific information relating to roof mounted and overhead fenestration products (skylights and sloped glazing) is available on the AAMA Skylight/Sloped Glazing Council web page:

60 60 Key Recommendations DOE is working on Zero Energy Buildings New window technologies will play a major role Select: Smart glass Smart thermal frames Smart spacers

61 61 Summary Increase in affordable technology Improved technology provides substantial economic and environmental benefits Sustainability will be the driving force in building design and performance specifications Companies embracing change will be the ones who prosper

62 62 Seminar Evaluation Please take a moment to complete the evaluation form. Thank You. Questions?