Types of inverter for grid tie solar electrical systems
We generally use one of two types of inverters for solar systems that are ‘grid tie’ - connected to the national power grid. They both perform the same basic function (converting DC power to AC power), but where they differ is how they are connected up to the solar panels and the rest of the system. The two types of inverters are string inverters and micro inverters. We can explain the options available to you and help you make the right choices for your site.
What is a string inverter?
STRING INVERTERS
A string inverter is a single inverter, with one or multiple strings of PV solar panels connected to it. Each string of solar panels is connected in series, producing a high DC (Direct Current) voltage.
In most situations we would recommend Fronius string inverter systems. The overall system cost is less, greater reliability and efficiency.
What is a micro inverter?
Micro inverters
Individual micro inverters mount and connect behind each solar panel, and are connected in parallel at 230vac. If you have 20 solar panels, you will have 20 microinverters, all of which operate independently.
Micro inverter systems can be a good option if you have multiple roof faces and orientations to locate your solar panels, or if you have potential issues with the shading of the solar PV panels.
What is the best Grid Tie inverter?
After many years of designing and installing PV solar systems, we have concluded that Fronius is the number 1 solution. Why is this?
Fronius inverters are designed and manufactured in Austria.
Fronius offer a 10-year warranty.
Fronius include web-based monitoring of both your solar production and energy consumption.
Fronius Gen24 inverters are battery ready, so you can easily add battery storage anytime.
The Fronius battery storage is DC coupled, so you can oversize your inverter more because the inverter can provide total output to the loads, while at the same time, any additional solar energy can still charge the battery.
With battery storage, in the event of a power outage, the system will continue to power your essential loads.
Fronius offers a black start, which means that during a power outage, if the battery goes flat, it will still charge up again when the solar starts producing energy and continue to provide energy to your essential loads.
Fronius offers PV Point. This means that without batteries, in the event of a power outage, the inverter will restart and power up a single outlet with up to 3kW of energy if the sun is shining.
Fronius offers additional add-on products to divert excess solar energy to your hot water cylinder and Electric Vehicle, which help increase your return on investment by increasing your self-consumption of solar energy.
It is often marketed that Micro inverters are essential if you have the potential for shading on your solar panels. This may have been the case some time ago, however this is not true now. The video link below explains this in greater detail.
Grid tie inverter products
