1. Designing With Light Erin Farrell Sep 25, 2006 http://www.keithv.com/scans/brugge_sunset.jpg

2. 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

3. 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

4. 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

5. ENERGY EFFICIENT LIGHTING

6. 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

7. 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

8. 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

9. 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

10. EFFICIENCY AND COST • Cost directly related to wattage plus any associated ballast • Higher the wattage, the higher the running cost

11. COST * Based on 10 cents per unit of electricity

12. 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

13. 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.