Are you looking for solar panels? Then you probably already know that you will need an inverter to generate usable power. You will also notice that the term "power optimizer" is used with particular frequency. In this article we will explain what an inverter is by sharing everything there is to know about string inverters and power optimizers with you.
What is an inverter, and how does it work?
The inverter is one of the essential parts of a solar panel system. There must be one to convert energy from the sun into usable energy, for example, from household appliances. In the Netherlands we use alternating current, which is the one supplied by the power sockets of the house. The solar panels instead generate direct current which is not immediately usable, except in the case in which it can be converted into alternating current, precisely, through an inverter.
Often, the inverter is located near the meter. In the case of the photovoltaic optimizers, each solar panel will have its own type of small inverter, also called a tracker or optimizer.
The different types of inverters
When choosing an inverter, you can select one of three different types:
- the string inverter (traditional);
- the micro-inverter; And
- the power optimizer.
The difference between the micro-inverter and the power optimizer is minimal. Both are used to increase efficiency in the event of darkening, dirt or malfunction of the panel.
The only difference is that power optimizers need a separate central inverter which ultimately converts the direct current of the solar panels into usable alternating current for home devices. And that micro-inverters need additional wiring that is on the roof, near the panels themselves. Aside from that, they both work the same way; so, for convenience, we will refer to a string inverter and a power optimizer in this article.
What is a string inverter?
When there is a string inverter, all the solar modules that are part of a long series are connected to the same inverter, perfectly aligned with the delivered power. This power depends on the weakest link in the series itself. If one solar panel malfunctions (for example, due to darkening, dirt, or because it is old or has a fault), all the others will malfunction.
What is a power optimizer?
A power optimizer and a micro-inverter work the same way. There is a power optimizer behind each solar panel. Thanks to these autonomous optimizers, every single solar panel can be optimized, and the weakest link in the series will no longer affect all the others.
The power optimizer is therefore recommended when one or more solar panels end up in a darkened condition. In this way, it is possible to make the panels “intelligent” and increase their total yield, especially in the aforementioned darkening situations.
In short, what is the difference between the two?
The main difference is that, through the traditional string inverter, the solar panels that work less well negatively affect the performance of the other panels. Thanks to a power optimizer the problem is solved thanks to the autonomous optimizer present behind each solar panel. This allows to optimize each single solar panel, and to obtain the maximum possible yield from each of them.
Do you want to be sure you are buying the right inverter? Let it be a company like the ESTG to give you information about it.