A study by the University of Southern Denmark (SDU) showed that in almost all applications, a PV system with cutting-edge string optimization technology can achieve greater energy production than a system with traditional DC optimizers, according to SMA America. SMA says the significantly lower component count in the string-based system also minimizes fault, fire and repair risk. In addition, installation labor and material costs are reduced and it is easier to carry out maintenance work.
SMA says its Shadefix shade management system makes it so there’s no need for additional components to mitigate the secondary effects of shade, which can increase the number of electronic components in the system by up to a factor of 30 compared with a system featuring traditional, module optimizers. This reduced component count significantly improves system reliability and reduces environmental waste.
SMA string inverters are developed with an integrated shade management system that effectively acts as a traffic officer directing the flow of electrons. It omits the additional components and energy consumption required by traditional optimizers that are constantly applying wear and tear to a system by increasing and decreasing voltage and current to generate incremental output. SMA has developed ShadeFix optimization to ensure maximum power production, even when modules experience a variety of shading conditions.
SDU associate professor Wulf-Toke Franke noted traditional module-based optimizers only achieved higher power output under heavily shaded conditions. He also said that error susceptibility increased in PV systems with module optimizers. More components in the system necessitated additional connections, increasing the risk of system failures and fires. On the whole, SMA claims the study contradicts general statements about additional energy generation through the use of optimizers. It found very few scenarios where the use of optimizers improved system performance.
News item from SMA America