Technology giant IBM claims it has developed a method of making solar cells that don’t rely on expensive semiconductors
IBM says it has developed a solar cell where the light-absorbing elements are made from readily available elements, which helps to improve efficiency and cut costs.
In a statement released late last week, IBM said the cell’s absorption layer is comprised of copper, tin, zinc, sulphur and selenium and is 40 percent more efficient than any other cell developed using similar materials.
“In a given hour, more energy from sunlight strikes the earth than the entire planet consumes in a year, but solar cells currently contribute less than 0.1 percent of electricity supply – primarily as a result of cost,” said Dr. David Mitzi, who leads the team at IBM Research that developed the solar cell. “The quest to develop a solar technology that can compare on a cost-per-watt basis with the conventional electricity generation, and also offer the ability to deploy at the terawatt level, has become a major challenge that our research is moving us closer to overcoming.”
Existing thin-film solar cells are made using expensive compound semiconductors such as copper indium, gallium selenide and cadmium telluride. These cells are usually 9 to 11 percent efficient says IBM and previous attempts to use more “earth abundant” materials have failed to become more than 6.7 percent efficient. IBM claims its latest cells are 9.6 percent efficient and potentially more affordable.
The IBM researchers outlined the development of the photovoltaic technology in a paper published in Advanced Materials last week. The researchers also used a different manufacturing technique based on nanoparticles rather than the usual but expensive vacuum-based techniques. “The production change is expected to enable much lower fabrication costs, as it is consistent with high-throughput and high materials utilisation-based deposition techniques including printing, dip and spray coating and slit casting,” the researchers said
Last month, Intel announced plans to install solar panels at eight locations in order to generate about 2.5 megawatts of renewable power. All eight solar power installations in Arizona, California, New Mexico and Oregon will be online within the next seven months, according to Intel officials.