When selecting a photovoltaic energy storage inverter, the inclusion of a pure sine wave inverter is crucial. A sine wave power inverter is a necessary component for any modern solar energy system. A. — PWM inverter technology, quasi-sine wave output, stable power supply. It's a device that converts direct current (DC) electricity, which is what a solar panel generates, to alternating current (AC) electricity, which the electrical grid uses. In DC, electricity is maintained at. Many of the appliances and devices we use rely on AC power, while solar panels, batteries or other energy storage devices produce DC power, so you need an inverter to convert it to AC power. DC power is pretty self-explanatory. In the case of solar cells, the current will vary fairly slowly through the day as the suns' intensity changes.