CRES12: Daylight Harvesting & Controls Presented by: Matthew Malone Northeast Sales Manager ® 20012 Crestron Electronics, Inc. Specifications subject to change. All copyrights and trademarks property of their respective owners. Update 08-16-12 Crestron Course #: CRES12: Daylight Harvesting & Controls Crestron Electronics, Inc. is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-AIA members are available on request. 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 will be addressed at the conclusion of this presentation. 2 Learning Objectives: By the end of this lecture the attendee will… 1. Define Daylighting and discuss the various benefits & concerns associated with it related to Commercial Architecture. 2. Define Daylighting Harvesting and gain an overview of the various Daylight Harvesting Techniques available. 3. Become familiar with the new changes in the Energy Codes that now require Daylight Harvesting. 4. Understand the terminology & control techniques necessary for a successful Daylight Harvesting system. 3 What is Daylighting? 4 What is Daylighting? • Daylighting’s objective is…to minimize the amount of artificial light thereby reducing electricity costs. • Daylighting is… the practice of placing windows or other openings and reflective surfaces so that during the day natural light provides effective internal lighting. • Daylighting can also…lower HVAC costs. Properly controlled natural daylighting generates hardly any heat compared to its electrical lighting counterpart. 5 Daylighting Techniques • Light Shelves • Light Wels • Sky Lights • Light Pipes Sky • Vertical Glazing Light Light Electric Light • Glass Interior Shelf Walls • Photovoltaics Light Light Glass Pipes Vertical Wells Walls Glazing Photo- voltaics 6 Daylighting Benefits 7 Benefits of Daylighting: • Full Color Spectrum 8 Benefits of Daylighting: • Full Color Spectrum • Aids bodies natural Circadian Rhythms & prevents Seasonal Affective Disorder 9 Benefits of Daylighting: • Full Color Spectrum • Aids bodies natural Circadian Rhythms & prevents Seasonal Affective Disorder • Saves Energy 10 Benefits of Daylighting: • Full Color Spectrum • Aids bodies natural Circadian Rhythms & prevents Seasonal Affective Disorder • Saves Energy • Improves end-user satisfaction/performance & consumer sales 11 Benefits of Daylighting: • Full Color Spectrum • Aids bodies natural Circadian Rhythms & prevents Seasonal Affective Disorder • Saves Energy • Improves end-user satisfaction/performance & consumer sales • High Demand, High Value, Corporate Image 12 Daylighting Concerns 13 Daylight Concerns: • Sky Factor Clear Sky Partly Cloudy Overcast 14 Daylight Concerns: • Sky Factor Clear Sky Partly Cloudy Overcast Amount of sun varies every day Number of days of sun per year varies with every city ‘Sunnier’ cities will have higher ROI and faster payback than others Control system needs to be commissioned appropriately for the climate type Commissioning requirements should be included in the programming scope and the CSI specifications to suit the clients expectations Example: Miami has quickly passing clouds, select a slower ‘Response time’ (2min.) Seattle has slowly passing clouds, select a faster ‘Response time’ (30 sec.) 15 Daylight Concerns: • Sky Factor • Building Orientation 16 Daylight Concerns: South-facing windows are most advantageous for daylighting and for moderating seasonal temperatures. They allow most winter sunlight • Sky Factor into a building but little direct sun during the summer, especially when properly shaded. • Building Orientation North-facing windows are also advantageous for daylighting. They admit relatively even, natural light, producing little glare and almost no unwanted summer heat gain. Although east- and west-facing windows provide good daylight penetration in the morning and evening, respectively, they should be limited. They may cause glare, admit a lot of heat during the summer when it is usually not wanted, and contribute little to solar heating during the winter. 17 Daylight Concerns: • Sky Factor • Building Orientation • Obstructions 18 Daylight Concerns: • Sky Factor • Building Orientation • Obstructions Understand that ROI for a project in a city with buildings in close proximity will vary from the same building in a rural setting or in a less crowded environment 19 Daylight Concerns: • Sky Factor • Building Orientation • Obstructions • Solar Heat Gain 20 Daylight Concerns: Low SHGC glass (Solar Heat Gain Coefficient) • Sky Factor Low U-Factor Glass (Heat Flow through • Building Orientation the window) • Obstructions Low AL (Air Leakage) • Solar Heat Gain Install Manual or Motorized Shades !!!!!! Install multiple layers of shades 21 Daylight Concerns: • Sky Factor • Building Orientation • Obstructions • Solar Heat Gain • Glare Too permanent, ruins façade of the building Makes it hard to work 22 Daylight Concerns: Size windows properly • Sky Factor • Building Orientation • Obstructions Install Manual or Motorized Shades !!! • Solar Heat Gain • Glare 23 Daylight Concerns: Install Manual or Motorized Shades !!! • Sky Factor Consider 2 layers of shades to correctly • Building Orientation manage daylight: Summer solstice, southern latitude - translucent fabric • Obstructions - black out shades • Solar Heat Gain Solar Tracking Install manual override • Glare Integrate with lighting control & AV scenes within the room Winter solstice, southern latitude 24 Daylight Concerns: • Sky Factor • Building Orientation • Obstructions • Solar Heat Gain energy savings > the price tag? • Glare • What is the Return on Investment (ROI)? 25 Daylight Concerns: • Sky Factor “What is the true ROI for Daylight Harvesting?” • Building Orientation • Obstructions • Solar Heat Gain Part 1 – The cost ($) of the Daylight Harvesting System • Glare Part 2 – The value ($) in Energy Savings Part 3 – The value ($) of Happy Tenants…priceless • What is the Return on Investment (ROI)? > $0.00 then a Positive Return on Investment ! 26 Daylighting Study 27 In a recent study by Lawrence Berkeley National Labs they attempted to answer two very important questions related to Daylight Harvesting … “Where are the Primary & Secondary Daylighting Zones located?” “How much Energy is saved in each Zone?” 28 Daylighting Study: Vertical Glazing: Primary & Secondary Zones 9’ 6’ Primary Secondary Third Primary Secondary Zone Zone Zone Zone Zone 0 to (10-15’) (10-15’) to 25’ 25’+ 0-11’ 11-31’ Example 1 Example 2 29 Daylighting Study: Horizontal Glazing: Primary & Secondary Zones Skylight Larger quantities of light than Vertical Glazing, but lacks views to the exterior 35° 35° h Cannot be used for LEED Secondary Secondary Indoor Environmental Zone Zone Quality Credit 8.2 h x 70% h x 70% Primary Zone 30 Daylighting Study: Energy Savings In a recent study by Lawrence Berkeley National Labs, they compared the energy for one year from a space with daylight harvesting to a space without daylight harvesting and found… Example B: LBNL Study - 9’ Glass Walls, all 4 sides of the building - Low Partition, Open Work Stations - Daylight Dimming Techniques used Primary Zone Energy Savings: West facing walls - saved 30% NW & SW facing walls - saved 50- 60% 9’ 30-60% 10-40% Secondary Zone Energy Savings: Energy Energy West facing walls - saved 10% Savings Savings NW & SW facing walls - saved 25- 40% 0-11’ 11-31’ 31 What is Daylight Harvesting? 32 What is Daylight Harvesting? A control system used in sustainable architecture that reduces the use of artificial lighting with electric lamps in building interiors when natural daylight is available, in order to reduce energy consumption. 33 Daylight Harvesting Techniques 34 Daylight Harvesting: Open Loop Systems Open Loop Sensor: Example #1 Skylight • The photosensor detects the amount of available daylight only • It can be positioned: • on the building's exterior wall or roof • or inside the building facing the skylight 35° 35° h Typical Open Loop h x 70% h x 70% Photosensor Example #1 35 Daylight Harvesting: Open Loop Systems Open Loop Sensor: Example #2 • The photosensor detects the amount of available daylight only • It can be positioned: • on the building's exterior wall or roof • or inside the building facing the skylight • or inside the building facing the window h • Allows multiple zones of fixtures to be controlled with a single photosensor Typical Open Loop h 2h Photosensor Example #2 36 Daylight Harvesting: Closed Loop Systems Closed Loop: Typical Closed Loop • The photosensor detects the combination of Photosensor daylight and electric light • It should be positioned: • away from direct sunlight • away from direct artificial light • where it can measure reflected light off a surface from both the natural and h artificial light • Allows you to define a single set point and vary the zones to achieve it • Each independently controlled zone requires h 2h a photosensor Example 37 Daylight Switching Vs. Daylight Dimming 38 Daylight Harvesting: Switching or Dimming?... Daylight On/Off Switching - once daylight level is reached,