Reportedly, the most efficient silver paste in the world will be exhibited at the PV Taiwan 2015 conference in Taipei. This paste has been said to have the world record for PERC efficiency, rated at 21.7%. PERC means passivated emitter rear contact, which is part of a different kind of solar cell architecture. The silver paste is made by the German company Heraeus.
“We are looking forward to form more partnerships with leading PERC cell manufacturers to customize our pastes to their specific cell designs. A stronger collaboration will allow us to maximize our customer’s cell performance and improve their competitiveness,” explained Dr. Weiming Zhang, Senior Vice President, Research and Development, Heraeus Photovoltaics.
In October, Heraeus signed an agreement with SAS Sunrise to help the company maximize the efficiency of its solar cells.
Silver is used in solar cells for the formation of contact grids, which are collectors of electrons. “Grids can be expensive to make and can affect the cell’s reliability. To make top-surface grids, metallic vapors are deposited on a cell through a mask or painted on via a screen-printing method.” In fact, about 10% of the world’s silver is used in photovoltaics.
You probably won’t find that many news articles about silver paste, but it is fascinating to consider how many companies work to support the solar power industry. They don’t make solar cells or panels and don’t install them, but they do produce important elements that make it possible for solar power to exist and to function.
The sub-text for these kind of technological successes is the ongoing research and development in new and more efficient solar power. Critics of solar power seem to perceive it as something that will not steadily improve, but it has been increasing in efficiency for decades. With more funding and research, it will undoubtedly continue to do so.