Is there such a thing as energy free lighting?  If so, why wouldn’t every building incorporate it?  The sun produces 383,000,000,000,000,000,000,000,000 watts of power in the form of light every day, often exceeding 1,000 footcandles, whereas interior light levels are on average only 50 footcandles.  Why not design buildings to harness the daylight into building interiors?

Following are a few benefits for daylighting:

1. Improved lifecycle cost – bringing daylighting into building interiors has been shown to save $0.05 - $0.20 per SF annually.
   
2. Increased occupant productivity – Several in-depth studies have been done on the positive affects of daylighting on people in interior spaces.
   
3. Reduced emissions – reducing the need for electric lighting and cooling reduces greenhouse gases and slows fossil fuel depletion.
   
4. Reduced operation cost - electric lighting accounts for ~30 percent of the total electrical energy consumption in commercial buildings.  By generating waste heat, lighting also adds to the loads imposed on a building's mechanical cooling equipment. Consequently, for many institutional and commercial buildings, total energy costs can be reduced by as much as one third through the optimal integration of daylighting strategies.
   
5. LEED points – incorporating daylighting will help with LEED credits: Energy and Atmosphere Credit 1 – Optimized Energy Performance and Indoor Environmental Quality Credit 8.1 and 8.2 – Daylight and Views.

Bringing daylight into buildings can be achieved with properly placed, high performance windows, skylights, or clerestory. Even interior spaces, with no windows can benefit from daylight with the use of Solatubes, refer to www.solatube.com for additional information.

To learn more, click on the following pictures: