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Title: Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat

Abstract

ABSTRACT Artificial lighting is the largest component of electricity use in commercial U.S. buildings. Hybrid solar lighting (HSL) provides an exciting new means of reducing energy consumption while also delivering significant ancillary benefits associated with natural lighting in buildings. As more than half of all federal facilities are in the Sunbelt region (defined as having an average direct solar radiation of greater than 4 kWh/m2/day) and as more than half of all square footage available in federal buildings is also in the Sunbelt, HSL is an excellent technology fit for federal facilities. The HSL technology uses a rooftop, 4-ft-wide dish and secondary mirror that track the sun throughout the day (Fig. 1). The collector system focuses the sunlight onto 127 optical fibers. The fibers serve as flexible light pipes and are connected to hybrid light fixtures that have special diffusion rods that spread out the light in all directions. One collector powers about eight hybrid light fixtures-which can illuminate about 1,000 square feet. The system tracks at 0.1 accuracy, required by the two-mirror geometry to keep the focused beam on the fiber bundle. When sunlight is plentiful, the optical fibers in the luminaires provide all or most of the lightmore » needed in an area. During times of little or no sunlight, a sensor controls the intensity of the artificial lamps to maintain a desired illumination level. Unlike conventional electric lamps, the natural light produces little to no waste heat and is cool to the touch. This is because the system's solar collector removes the infrared light-the part of the spectrum that generates a lot of the heat in conventional bulbs-from the sunlight.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
991661
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: World Energy Engineering Congress (WEEC) 2006, Washington, DC, USA, 20060913, 20060915
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; ACCURACY; DAYLIGHTING; DIFFUSION; DIRECT SOLAR RADIATION; ELECTRICITY; ENERGY CONSUMPTION; FIBERS; GEOMETRY; GOVERNMENT BUILDINGS; ILLUMINANCE; LIGHT BULBS; LIGHT PIPES; MIRRORS; OPTICAL FIBERS; SOLAR COLLECTORS; SUN; WASTE HEAT; hybrid solar lighting FEMP energy savings

Citation Formats

Lapsa, Melissa Voss, Maxey, L Curt, Earl, Dennis Duncan, Beshears, David L, Ward, Christina D, and Parks, James Edgar. Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat. United States: N. p., 2006. Web.
Lapsa, Melissa Voss, Maxey, L Curt, Earl, Dennis Duncan, Beshears, David L, Ward, Christina D, & Parks, James Edgar. Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat. United States.
Lapsa, Melissa Voss, Maxey, L Curt, Earl, Dennis Duncan, Beshears, David L, Ward, Christina D, and Parks, James Edgar. Sun . "Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat". United States. doi:.
@article{osti_991661,
title = {Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat},
author = {Lapsa, Melissa Voss and Maxey, L Curt and Earl, Dennis Duncan and Beshears, David L and Ward, Christina D and Parks, James Edgar},
abstractNote = {ABSTRACT Artificial lighting is the largest component of electricity use in commercial U.S. buildings. Hybrid solar lighting (HSL) provides an exciting new means of reducing energy consumption while also delivering significant ancillary benefits associated with natural lighting in buildings. As more than half of all federal facilities are in the Sunbelt region (defined as having an average direct solar radiation of greater than 4 kWh/m2/day) and as more than half of all square footage available in federal buildings is also in the Sunbelt, HSL is an excellent technology fit for federal facilities. The HSL technology uses a rooftop, 4-ft-wide dish and secondary mirror that track the sun throughout the day (Fig. 1). The collector system focuses the sunlight onto 127 optical fibers. The fibers serve as flexible light pipes and are connected to hybrid light fixtures that have special diffusion rods that spread out the light in all directions. One collector powers about eight hybrid light fixtures-which can illuminate about 1,000 square feet. The system tracks at 0.1 accuracy, required by the two-mirror geometry to keep the focused beam on the fiber bundle. When sunlight is plentiful, the optical fibers in the luminaires provide all or most of the light needed in an area. During times of little or no sunlight, a sensor controls the intensity of the artificial lamps to maintain a desired illumination level. Unlike conventional electric lamps, the natural light produces little to no waste heat and is cool to the touch. This is because the system's solar collector removes the infrared light-the part of the spectrum that generates a lot of the heat in conventional bulbs-from the sunlight.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Conference:
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