Solar inverters – what makes them good? Well it turns out this is a little more complex than you might think. Here are some factors (ranked in order of importance) that the ideal inverter would have:
- High efficiency
- Excellent reliability
- Advanced MPPT system
- Low noise
- No heat or overheating
- Excellent power quality
Why should solar inverters have high efficiency?
The job of the solar inverter is to convert the DC power produced by solar panels into power you can use in your home (AC power). As you can imagine, every little drop of sweet solar electricity is valuable and the less power lost to inefficiencies means more dollars in your pocket. Nowhere is this more important than when changing from DC to AC. This is the major point at which power could be lost. So the more efficient the inverter, the more power you’re getting delivered from your solar panels to your appliances.
Solar inverter reliability
Solar inverters are the heart of a solar power system. Reliability is one of the most important factors in making sure you get a top-notch inverter. This basically boils down to whether or not the inverter will fail, when it will fail and how sever the problem will be. Typically, German inverters (specifically SMA inverters) are known for having excellent reliability with very few failures. ABB Power-One (Aurora) inverters tend to be more prone to failures, although usually this is not a systemic problem – e.g. when they work, they work very well but occasionally you get inverters straight from the factory line which fail on the day of installation. Chinese inverters are difficult to judge. There are now so many Chinese companies making solar inverters that you’re bound to get some dodgy ones and some good ones.
Solar Inverters MPPT system
An MPPT system is a “maximum-power-point-tracking” system. The maximum power point (MPP) is the point at which your solar produces the most power. The tracking is done via sophisticated programs. Getting this right will make a big difference to the energy produced by your system.
What About Solar Micro-Inverters?
Micro-inverters work far more efficiently than a standard inverter – you usually get at least 6% better energy production from micros mainly due to their ability to work on an individual panel basis – this is similar to MPPT but much more efficient. You do pay for it though.
Solar inverters & heat!
Solar inverters are not made to be in the sun! Heat is one of the worst enemies of any electronic device. In the past, there have been instances where inverters have over-heated and this can cause catastrophic failures. Best to get an inverter with an efficient heat dissipation design and mount it somewhere shady and well-ventilated.
Power quality of solar inverters
Solar inverters tend to generally have extremely good power quality. If they pass Australian Standards and make the CEC approved inverters list, chances are your power output will be better quality than what comes out of the wall socket in your home!