Solar Power Inverters Inverters process the electricity produced by a solar power system to make it suitable for meeting the specific demands of the load. It is extremely important to match the capabilities of these devices with the characteristics of the equipment that will be using the power. Inverters typically have to perform these functions: Modify the current and voltage provided by the solar energy panels to maximize electric power output Convert DC power from the panels to AC power usable by most business and home devices Match the converted AC power to the voltage and frequency of the utility's electrical network Safeguard the utility network system and its personnel from possible harm during repairs Prevent damage to the solar energy array and other components during unusual operating conditions. Major design considerations for inverters include their capacity, voltage rating and battery capability. The SMA 2500U inverter shown to the right is a new design that operates at a relatively high input voltage (up to 600 VDC). This design allows the installer to string all the solar power modules in series, thereby significantly reducing wiring runs. In addition, the high operating voltage minimizes transmission losses. The result is a system that operates at a very favorable dollar per watt basis. As shown to the right, multiple inverters can be combined (these two inverters provide a total of 5,000 watts AC output). Inverters are often installed in the control center along with switches, fuses, and other electrical components. These components must be able to withstand expected temperature extremes in both operating and non-operating states. Certified electrical service boxes must be used. Since high temperatures and dust will shorten the life of unprotected electronic equipment, inverters should generally mounted in dry, dust free, ventilated areas. Air inlets and filters for inverters that use ventilation fans for cooling should be cleaned regularly. New inverter models that use large external heat sinks instead of fans and are constructed with sealed enclosures can be mounted in exposed locations. Although the SunnyBoy inverter shown above is the most popular and reliable inverter for small systems, once system capacity gets above 20kw, larger capacity inverters begin to make good economic and engineering sense. Trace Technologies makes a series of commercial inverters that range in size from 15kw up to 225kw. These inverters operate at 208 volts for compatibility with industrial power systems, have active cooling fans to handle high outputs, and built-in remote communications capabilities.