Horizontal Hybrid Solar Light Pipe: an Integrated System of Daylight and Electric Light

EPA Grant Number: SU834349
Title: Horizontal Hybrid Solar Light Pipe: an Integrated System of Daylight and Electric Light
Investigators: Beltrán, Liliana O.
Current Investigators: Beltrán, Liliana O. , Camacho, Gema , Diaz, Oscar , Farias, Francisco , Fernández-Solis, José , Gignac, Nicholas , Jiang, Yin , Lee, Johnny , Mansour, Nesrine , Miller, Paul , Negandhi, Vanita , Pathak, Rutuparna , Porwal, Vishal , Shirodkar, Rohan , Wang, Julian
Institution: Texas A & M University
EPA Project Officer: Nolt-Helms, Cynthia
Phase: I
Project Period: August 15, 2009 through August 14, 2010
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2009) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Built Environment , P3 Challenge Area - Energy , P3 Awards , Sustainability


This project will test the feasibility of an advanced energy efficient perimeter lighting system that integrates daylighting, electric lighting, and lighting controls to reduce electricity consumption. The system is designed to provide adequate illuminance levels in deep-floor plan spaces during building operating hours year-round.

Our proposed hybrid light pipe is a unique system that integrates daylight with high-efficiency electric light sources (i.e. LED, sulfur lamps) and intelligent lighting controls to offset the use of standard light sources in the core of buildings mainly during peak demand hours. Our team believes that technology is currently available to produce a hybrid solar lighting system based on the efficient design of a horizontal light pipe and the intelligent use of materials. It will be possible to passively introduce adequate light levels to illuminate areas between 15 to 40 feet from the perimeter of the building. Preliminary evaluation of the light pipe has shown that it can provide high illuminance levels, 300-1,500lux at the back of the space (15-30ft) for more than 7 hours (between 8:45am to 4:15pm) under clear skies.


The goals of this project are to: (1) quantify the energy savings of an integrated hybrid solar light pipe system over extended periods throughout the year; and (2) give students invaluable hands-on learning experiences in high-efficiency lighting design. The proposed system will passively integrate daylight and electric lighting in a single unit. The objectives of the proposed lighting unit are to: (1) extend the daylighted area of the perimeter zone of the building from 15 feet to 40 feet; (2) provide adequate brightness at the back of typical spaces without the associated high daylight/ solar radiation levels near the windows; (3) integrate auxiliary electric lighting; and, (4) reduce the energy consumption in buildings and slow fossil fuel depletion.


To develop the lighting system, the team will execute the following tasks: (1) research of materials and selection of individual components; (2) design and computer modeling of proposed light pipe; (3) lighting design optimization (daylight and electric light); (4) design/ interaction of electric light sources (color change capability and dimmable), and lighting controls; (5) construction of light pipe and assembling of components; (6) installation of system in testing room; (7) data acquisition set-up and preliminary data collection.

Expected Results:

The expected outcome of this research will be the construction and installation of the proposed lighting unit in an existing space (20 ft wide by 30 ft deep) at the TAMU-College Station campus. The system will be monitored continuously for a whole year to collect data of the lighting performance and energy consumption under different sky conditions and different sun position. The lighting performance of the light pipe will be assessed both quantitatively (illuminance and luminance levels) and qualitatively (visual inspection and High Dynamic Range photography).

Supplemental Keywords:

energy efficiency, natural light, daylight controls, human comfort,

Relevant Websites:

Phase 2 Abstract

Progress and Final Reports:

  • Final Report
  • P3 Phase II:

    Horizontal Hybrid Solar Light Pipe: an Integrated System of Daylight and Electric Light