designing with
DESCRIPTION
Designing With. Light. Erin Farrell Sep 25, 2006. http://www.keithv.com/scans/brugge_sunset.jpg. LIGHT FACTS. Most efficient light is natural light Artificial light is almost 15% of a household's electricity use New lighting technologies can reduce lighting energy use in homes by 50%–75% - PowerPoint PPT PresentationTRANSCRIPT
DesigningDesigningWithWith
LightLight
http://www.keithv.com/scans/brugge_sunset.jpg
Erin Farrell
Sep 25, 2006
LIGHT FACTS
• Most efficient light is natural light
• Artificial light is almost 15% of a household's electricity use
• New lighting technologies can reduce lighting energy use in homes by 50%–75%
• If you replace 25 percent of your light bulbs in high-use areas with fluorescents, you can save ~50% on your lighting bill
DAYLIGHTING
• Orientation– In northern hemisphere, greatest solar gain is on
the south elevation– Siting building diagonally to the south takes
maximum advantage of available sunlight
• Interior Design– What rooms serve what purpose? How can design
take advantage of natural sunlight?– Kitchen on east side – light in morning– Living/dining room on west side – light in evening
when sun setting
DAYLIGHTING
• Maximize light availability to rooms
– Design so light can enter every room from at least two sides
– If second side isn’t possible, consider gathering light from above
• Skylight; ridge skylight; light monitors, dormers, clerestory windows; light shelf
• Light pipes
ENERGY EFFICIENT LIGHTING
Incandescent
• Most commonly used
• Heat electric element to white hot
• Inexpensive to buy; running costs high
• Least energy efficient – only 10% energy consumed produces light; rest is heat
• Do not last long, so suitable for areas of infrequent or short period use
Fluorescent
• Most efficient
• Cause phosphor coat inside of glass tube to glow
• Produce less heat
• More expensive to buy; running costs lower
• Suitable to areas requiring long period use
Fluorescent: two types
• Compact– Usually designed to fit into conventional light
sockets– Four times more efficient and last up to 10 times
longer than incandescents– Use 50-80% less energy than incandescents
• Tubular– Straight or circular style– Cheaper than compact; but require special fittings
Fluorescent: ballasts
• Used to start fluorescent lamps
• Can be magnetic or electronic
• Magnetic – Older type; less expensive; cannot be dimmed
• Electronic – Newer type; more expensive but more energy efficient; start lamp quicker; some units can be dimmed
EFFICIENCY AND COST
• Cost directly related to wattage plus any associated ballast
• Higher the wattage, the higher the running cost
COST
* Based on 10 cents per unit of electricity
20 W CFL 100 W Inc.
Running cost over 10,000 hrs*
$20 $100
Avg life 10,000 hrs 1,000 hrs
Purchase cost $25 for 1 lamp $5 for 10 bulbs
Total Cost $45 $105
FINAL FACTS
• In a typical home, one compact fluorescent bulb can reduce carbon dioxide emissions by 260 pounds per year
• If every American household replaced one of its incandescent light bulbs with a CFL, it would save the same amount of energy as a large nuclear power plant produces in a year
• Saving electricity reduces CO2 emissions, sulfur oxide and high-level nuclear waste
Works Cited• http://oikos.com/library/eem/skylights/lightpipes.html
• http://www.greenhouse.gov.au/yourhome/technical/fs10.htm
• http://www.eartheasy.com/live_energyeff_lighting.htm
• http://www.eere.energy.gov/consumer/your_home/lighting_daylighting/index.cfm/mytopic=11980
• http://www.eia.doe.gov/kids/energyfacts/saving/efficiency/savingenergy_secondary.html
• Jacobson, M., Silverstein, M., Winslow, B. (October/November 2002). Fine Homebuilding. Designing a House for the Sun: 4 Strategies.