Cadmium telluride is normally referred to as the "dark-horse" of the thin film PV technology. However, with a band gap of 1.45 eV it has an optimum match with the solar spectrum. A practical efficiency of 18% is possible with existing device design, and theoretical limits are as high as 27.5% (Sites, 1988, Fig.6; i. e., even higher than CuInSe2 or silicon).
Voltage at Max Power (Volt)
Fig. 6. Various loss mechanisms in CdTe devices
Y. S. Tyan and E. A. Perez-Albueme of Kodak were the first to report achieving 10% efficiency in 1982...Read More
For the past several years, CuInSe2 has made considerable progress and currently is considered the leading thin-film material in terms of efficiency and long-term reliability (Zweibel and cowoikers, 1990). Practical efficiencies of 16% are possible with existing cell design, with theoretical limits of 23.5% for CuInSe2 devices (Sites 1988, Fig. 2). Several methods are available for depositing thin-film CuInSe2. This is reported by Ullal and coworkers (1991).
Mickelsen and Chen at Boeing Aerospace were the first to report on 10% efficient CuInSej solar cells by coevaporation in 1982. Since then, Boeing has improved the device performance to a total-area efficiency of 12.5% by the addition of Ga (Ga:In, 27:73). The most significant improvement has been in Voc of the device to 555 mV...Read More
Harin S. UllaJ, Kenneth Zweibel, Richard L. Mitchell, Rommel Noufi
Solar Energy Research Institute
1617 Cole Boulevard
Golden, CO 80401, USA
Low-cost, high-efficiency thin-film modules are an exciting photovoltaic technology option for generating cost-effective electricity in 1995 and beyond. In this paper we review the significant technical progress made in the following thin films: copper indium diselenide, cadmium telluride, and polycrystalline thin silicon films. Also, the recent U. S. DOE/SERI initiative to commercialize these emerging technologies is discussed.
Cadmium telluride, copper indium diselenide, modules, photovoltaics, polycrystalline thin films, silicon film, solar cells.
Substantial technical progress has be...Read More