Solar energy can be converted to electricity for our homes with the help of solar panels. Solar power doesn’t require burning coal in order to be produced and it is going to be around for quite some time. But for a household to make use of solar power, it needs more than just panels. Amongst other things such as batteries and charge controllers, a solar power system also needs an inverter.
What Is a PV Inverter?
A photovoltaic inverter is a device used to convert DC power to AC. When a panel converts photovoltaic cells into electricity, it does so in DC. With a powerful enough grid connect inverter, this power is converted to AC in order for appliances to be able to use it.
How Do Solar PV Inverters Work
Inverters work by taking DC current from the panel and sending it through a transformer. Then, the DC current goes through a couple of transistors that turn on and off rapidly and feed the two varying sides of the transformer. Basically, a solar grid connect inverter tricks the transformer by mimicking how AC power works.
Solar PV Inverter Solutions
String
Since solar panels can be wired in the form of a string, there are inverters that can handle the load from string connected panels. String inverters are the least expensive option you will come across but they do come with some downsides. One of them is a power drop. If a drop in power occurs in one panel, it affects the whole string of panels. This power drop can be caused by something as minor as a shadow but sometimes it can be because of a faulty panel. While some string inverters are able to manage these issues better than others they are still not as good as power optimizers.
Power Optimizer
These PV inverters are based on an inverter system similar to the one string inverters use. Power optimizers come with an external MPPT component which is how they got their name. The benefit of these PV inverters is that when there is a power drop, it only affects one panel. This is because each panel has one independent power optimizer. This allows you to have panel-level monitoring and it also means that the cost of this PV inverter system is a lot higher than the one of a string inverter.
Micro
If you want a solution that can both manage the power for each panel and a whole array of panels, you should consider getting microinverters. Microinverters are small versions of power optimizers with more options. You can hook up up to 4 panels on one microinverter at a time or have one micro inverter for each panel. This gives you maximum flexibility both when it comes to expansion and monitoring output levels.
Hybrid
If you want a 3-in-1 package, then hybrid inverters are the best option for you. These inverters incorporate a battery and a charge controller alongside an inverter. Keep in mind though, although they help save space and money they won’t run as efficiently as a dedicated PV inverter.
Sine
Sine wave inverters allow you to run the majority of your home appliances. Sine wave inverters are split into two categories, pure sine wave and modified sine wave. The former is needed for grid-tied systems while the latter is used for simpler systems that power delicate electronics.
These include laptops, battery chargers, digital clocks with radios, laser printers, photocopiers and anything with a thyristor or a silicon-controller rectifier in it. Modified sine wave inverters can also power medical equipment such as oxygen concentrates, home automation systems, fluorescent lights, pellet heaters and furnaces with microprocessor controls such as washing machine controls.
Square
Square sine wave inverters are known as digital inverters. They cannot power a lot fo home appliances as they only power appliances that run sine wave AC pattern only. Square sine wave inverters make a humming noise when they run and they are not recommended for your home appliances.
Stepped
A middle ground between sine wave and square wave inverters are the stepped wave inverters. They are not as common as they are made to be a low-cost solution for computers and other electronic gadgets. This is a very limited type of inverter thus it is not used as much as a modified sine wave inverter which is what the majority would get when powering a household.