The Fraunhofer Institute for Solar Energy Systems (ISE) from Freiburg, Germany, has set a new world record of 99.03 % for the efficiency of PV inverters.
|99.03 % thanks to silicon carbide. The modern components are still expensive, but they have proven their efficiency. |
"We now use junction field-effect transistors made of silicon carbide and manufactured by Semisouth Laboratories Inc. This is the main reason for the improvement", explains Prof. Bruno Burger, leader of the Power Electronics Group at Fraunhofer ISE. "In addition, we have optimized the gate units and many other details of the circuit."
In practice, this not only improves efficiency: higher efficiency implies lower thermal losses, smaller cooling devices and a more compact construction. These savings also help to compensate for the higher price that has to be paid, especially for the silicon carbide components. Burger states: "I see enormous potential for the new silicon carbide transistors. They are constantly becoming better and less expensive, whereas the costs for passive components containing significant amounts of copper and other metals are rising continuously."
The efficiency world record was measured for a complete PV inverter, including its internal power supply, a digital signal processor for controls, a grid filter and a relay for connection to the grid.