The electric grid and all devices which run on electricity use alternating current, therefore it is extremely important to switch the solar power being generated with an inverter. Although a small number of solar energy producing products are able to transfer DC power directly into devices, the majority of solar arrays and other units require a solar power inverter for the power to be transferred to the electrical grid.

Types of Solar Power Inverters

There are three distinct types of solar energy inverters, each of which serve a different function and are used for a different type of solar energy system, although each inverter still converts DC into AC:

• Stand Alone Inverters
• Grid tie Inverters
• Dual Inverters

Smaller stand alone inverters are used in a variety of products including solar battery chargers for laptops, cell phones, water pumps, and even to charge a car battery. These inverters are necessary for locations where no local power grid is available, or for anyone who wishes to remain completely independent of energy companies. 

With a stand alone system, you will be unaffected by power outages because your system will be completely independent from the power grid. You will be free to consume electricity whenever you wish, provided your batteries are charged or your solar array is currently producing electricity.

If you wish to run any large appliances or equipment off your stand alone solar system, then it is necessary that you purchase a surge compliant inverter. These inverters are also necessary for most any residential or commercial off-grid solar application. Large electronics require a surge of energy when first being turned on, so therefore it’s necessary that your inverter is able to supply this surge of electricity when required. Most larger off-grid inverters have this capability, although always be sure to check before you make a purchase.

Grid tie inverters are for use in any situation where your solar array is connected directly to your local power grid. These systems, known as grid tie solar systems, are more common in urban areas and are much cheaper than stand alone or off-grid systems because of the lack of need for a battery. In grid tie solar systems, direct current is generated by the solar panels, which then send this DC energy to the grid tie inverter. 

This energy is then converted into alternating current by the inverter, and finally sent directly into the local power grid. In this type of system, it is necessary to have your solar unit wired to your grid via your electricity meter, thus ensuring that you receive credit from the power company for any energy you produce.

This type of system is best suited for smaller scale solar arrays, and offers no protection in case of power outages because of the lack of a backup battery. In this type of system, some people argue that you are not technically consuming any of the electricity that you are producing, as it is sent directly back into the grid.

All grid tie systems are required to have a solar energy inverter with anti-islanding protection which forces them to shut down in case of power outages. Without anti-islanding protection, your solar system would continue to generate electricity and send small amounts back into the electric grid during power outages. This energy would stay in the local power grid and is referred to as an island. These islands can be extremely dangerous for utility workers who are trying to repair the gird during a power outage. 

Before purchasing a grid tie solar power inverter - especially if you are buying a used inverter - always make sure to check that the inverter has anti-islanding protection, as it is illegal and can be extremely dangerous to install a grid tie system without it. You probably won’t find any grid tie inverters on the market without it, but checking to make sure is still a great way to ensure you are purchasing the correct inverter for your particular solar system.

Dual inverters are also known as backup battery inverters and are used in a multi-function solar system. In this system, the direct current generated by the solar panels is first sent directly to a battery. 

The energy from the batteries is then sent to the inverter and converted to alternating current whenever electricity is required. However, when the batteries are fully charged, any excess direct current electricity that is generated is sent directly to the inverter and is then sent into the local power grid. This system combines the other two systems into one self-reliant and possibly money generating solar unit. 

This type of solar energy inverter is obviously more expensive than the other two types because it contains all of the benefits of the others. It allows you to produce, store, and consume any electricity that your solar system produces, while also maximizing your systems energy production by sending any extra energy into the local electrical grid which has the ability to generate profit. 

It also ensures that you will still be able to consume electricity even if your system isn’t functioning, as your property will still be connected to the grid. The major benefit of this type of solar energy inverter is that you will still be unaffected by power outages as long as your solar batteries are charged or your system is producing electricity.

Back to Solar Energy Home