| Abstract |
Despite high rates of electrification in China, 25 to 30 million people remain without access to electricity. This population, as well as those with only intermittent access, must rely on alternate sources of power for their lighting needs. This paper presents a comparison of available off-grid and grid-based lighting options in terms of performance and economics, which is then contextualized using a case study of semi-nomadic populations in rural Tibet. Fuel-based lighting is shown to be significantly more costly than solar-powered compact fluorescent lamps (CFLs) and solar-powered light-emitting diode (LED) alternatives per unit of lighting services delivered. We calculate that a hurricane-style kerosene lamp costs approximately $0.40 per thousand lumen hours (klmh) or $2.89 per thousand lux hours (klxh), while a solar-CFL lantern costs $0.17/klmh and $1.20/klxh and a solar-LED device costs $0.15/klmh and $0.03/klxh. Furthermore, as LED efficiencies continue to improve, solar-LED products will become even more economical. Three focus groups and 15 household interviews were held among off-grid populations in rural Tibet to gauge response to LED technologies. LEDs were universally ranked below CFL alternatives, primarily due to the directional nature of the LED devices exhibited, but were still ranked above all non-electric sources of light. Diffusing optics may thus need to be incorporated into solar-LED lighting systems before they are rated as more attractive for general illumination than solar-CFL systems. Accordingly, those surveyed placed a high value on the use of LED bulbs for flashlight applications. Finally, we note that despite the potential benefits of LEDs, market forces are not likely to spur innovation in solar-LED lighting options for the unelectrified populations of Tibet, as the design of these systems is dominated by the governmental bodies subsidizing their distribution. Unless this structure changes, the future development of LED-lighting technologies will depend on top-down investment from the central and local governments. |
