The rule of thumb is to size your inverter 1. 25 bigger than your solar array. In some cases, you may need to use multiple inverters to meet your power needs or increase your system's voltage.
Choosing the right size solar inverter is crucial for the performance and efficiency of your solar system. By considering your power needs, the type of solar panels you have, the number of panels, the length of your wires, and your battery voltage, you can determine the optimal size for your solar inverter.
Correct sizing of a solar inverter is crucial. The wrong inverter capacity will weaken the performance of the solar panel system. The inverter has to be able to deal with the amount of energy it's getting from the panels. Inverter sizes are measured in watts (W) or kilowatts (kW) – units of a thousand watts – the same as solar panels.
Apart from solar panel system size, roof size, location and temperature, other factors that can influence the size of inverter you'll need include: The angle of your solar panels, and their orientation relative to the sun. Shade from neighbouring buildings or nearby trees. The amount of dust or pollution in the air.
An important consideration in calculating inverter size is the solar panel system:inverter ratio. This is the direct current capacity of the solar array divided by the maximum alternating current output of the inverter. For example, a 3kW solar panel system with a 3kW inverter has an array-to-inverter ratio of 1.0.
Using the example of ten 300-watt panels, your total power output is 3,000 watts. Solar inverters have an efficiency curve, which shows how efficiently they convert DC power from the solar panels into AC power for your home. In general, look for an inverter with an efficiency rating above 95%.
For instance, a 3kW solar panel system needs a power inverter of 3kW or thereabouts. The capacity ratings don't necessarily have to match exactly. Inverters can be sized lower than the kilowatt peak (kWp) of the solar array. This is because solar panels rarely achieve peak power.