Solar

Higher Solar Efficiencies Could Surface

SunPower announced the discovery of “surface polarization,” a performance detriment observed in silicon PV solar cells. As the result of their discovery, SunPower scientists have developed and applied for patents that eliminate surface polarization, which the company believes will lead to improved solar efficiencies.

According to the company’s researchers, surface polarization creates nondestructive and reversible accumulation of static charge on the surface of high-efficiency solar cells. It occurs when minute amounts of electrical current leak through the face of the solar cell and accumulate on the surface. Current leakage of this sort is present in all solar systems but will accumulate or dissipate on the solar cells’ surface depending on system grounding polarity and configuration. The presence or absence of surface charge can decrease or increase solar cell current generation similar to the switching of a programmable memory transistor. SunPower found that electricity production in systems using high-efficiency solar cells could be significantly decreased or increased by varying the system wiring and grounding configurations, and that these performance changes were relatively rapid and completely reversible. “We believe that the surface polarization effect will be seen in many types of high-efficiency crystalline solar cells,” said Dick Swanson, SunPower’s founder and CTO. “We are pleased that our research and development team discovered and characterized surface polarization and subsequently developed practical measures to eliminate this effect in real-world PV system configurations.” SunPower http://www.sunpowercorp.com