Solar Power Inverters
Solar Power Inverters
At the heart of every solar power system is the inverter, so what exactly is a solar inverter, what does it do and why do solar power systems need one?.
A solar inverter is a device that converts DC electricity generated by the solar panels into AC electricity. AC electricity is the same as the power that comes out of your homes power points, DC is what comes from batteries.
Solar inverters vary in size according to the size in kW of the system. Inverters are usually mounted somewhere on a wall out of the weather in a secure and easy to access place.
A good quality solar inverter is essential for optimum system performance and efficiency, even with the best solar panels installed your system will not perform to its full potential if the inverter is not up to high standard.
There are three basic types of grid connect solar inverters, micro, string and central each of these has advantages and disadvantages.
Below are some images of solar inverters.
A micro inverter is a small inverter that converts DC to AC for one individual solar panel. Micro inverters are usually attached to each solar panel mounted on the roof so there is one micro inverter for each panel operating independently.
Advantages of Micro Inverters:
- Solar panel maximum power point tracking
- If one panel in the system is not performing this will not effect the entire system or array
- Panel output level monitoring
- Lower DC voltage flowing through cabling
- More flexible design possibility
- Individual panels can face different directions
- Better system performance where partial panel shading occurs
- Simple system design
- Different solar panels can be used in the system
Disadvantages of Micro Inverters:
- Costs more to install compared to string inverters
- Inverters are installed in a position that may expose them to the elements and in some cases extreme heat
- Maintenance will cost more due to the inverters need to be mounted in a hard to get to location like a root top
A string inverter is the most common type of inverter installed in most Australian home solar systems. A string inverter looks like a large wall mounted box around the same size as your switchboard box, depending on the size of the system more than one string inverter may be installed to operate in tandem.
Advantages of String Inverters:
- Good system design flexibility
- Sturdy and highly efficient unite
- Available in 3 phase
- Best value for money
- Excellent product support for the top brands
- Possibility to set up remote system monitoring
Disadvantages of String Inverters:
- No solar panel power point tracking
- High voltage can be a safety hazard, however if installed correctly this should not be a problem
A central inverter is basically a much larger string inverter, this type of inverter is used for large scale solar arrays such as those mounted on industrial buildings and office blocks or large ground mounted solar arrays.
Advantages of Central Inverters:
- Low cost per watt of power produced
- Highly efficient
- Easy to install, usually one unit is needed
Disadvantages of Central Inverters:
- Large installation space is needed
- Noise may be an issue
- If the unit fails the entire system stops working.