We’re at a precipice in history. Solar power and other renewable energy options have become much cheaper and more convenient than traditional fossil-fuel energy found on the electric grid.
At the heart of this revolution is a little known device—the solar power inverter.
If solar power is the superhero of the green revolution, solar power inverters are their sidekicks.
You see, solar power captures energy from the sun in a form known as direct current (DC). However, this energy form is pretty unusable for use with standard electric devices in Australia because:
- Most homes are wired to conduct alternating current (AC) energy.
- It’s difficult to convert DC into different voltages.
- DC flows continuously, making it hard to escape electrocution.
- DC’s susceptibility to electrical resistance makes its transmission expensive.
For these reasons, you need a good solar power inverter to convert the DC energy from your panels into the usable AC form.
Today, we’ve compiled a list of important facts that you should know before purchasing a solar power inverter.
1. Inverters Come In Different Shapes and Sizes
The first thing you must know about inverters is that they can be as different from each other as night is from day.
Generally, inverters are classified into two major groups:
- String inverters
String inverters refer to centralised inverter units that convert DC from multiple solar panels into usable AC energy.
String inverters work by aggregating DC power from the solar panels into groups called “strings.”
These strings are then sent through semiconductors, such as metal oxide semiconductor field-effect transistors (MOSFETs), to periodically reverse the direction and magnitude of their current, thus transforming DC into AC.
String inverters can handle the work of 5–10 microinverters and are typically the most popular because they are safe, efficient, durable and reliable.
As such, they’re largely preferred for use in residential and commercial units.
Victron Energy Phoenix Smart Inverter 18.6-34VDC input - output VPSINV-24/1600 is one of the best string inverters on the market.
Exclusively sold by Off Grid Direct, it uses pure sine wave technology, a system in which AC voltage is modified to rise and fall smoothly. This method of energy delivery reduces power loss, audibility from static and electrical damage to heavy equipment.
This lightweight and compact inverter has an output voltage of between 210 and 245 volts of AC (VAC). It’s therefore suitable for powering equipment like LED lamps, halogen lamps and electric tools.
Pro Tip: To maximise power output generated by using string inverters, ensure that none of your panels are obstructed by shade from trees or damage.
String solar power inverters can be very sensitive to shade because they acquire power from multiple panels. Because of this, they’re just as good as their lowest-performing panel.
Microinverters are a group of miniature inverters that manufacturers custom-build onto individual solar panels.
They contain a series of connected, silicon-based insulated gate bipolar transistors (IGBTs) that transform DC into AC by rapidly flicking. This creates DC current, which travels in one direction to periodically reverse its direction and magnitude.
Microinverters are usually considered a good way to optimise solar energy production since their ability to convert DC into AC is not hampered by the performance of other panels.
That’s to say, if one panel is blinded by shade, the other panels will still produce energy because they’re not affected.
For this reason, the average 300 watt microinverter can convert 24–48 volts of DC into 120–230 volts of AC (VAC).
Despite this, microinverters are beyond the reach of most people as they have high installation costs. As such, they might not be feasible if you’re in need of good solar power inverters for your residential home.
2. Inverters Are Very Sensitive to Solar Panel Power Output
One of the most important factors you should consider before purchasing a solar power inverter is whether it suits your needs.
Modern inverters have maximum power output ratings, which they cannot surpass. Instead, they will “clip” any excess power generated to protect your devices from damage due to electric shock.
It’s important to ensure that your inverter’s output closely matches those generated by your solar panels.
This starts with knowing how much DC power your solar panels are capable of generating.
You can then use this metric to calculate the inverter load ratio, a measure of the DC power generated compared to the AC power generated.
For example, if you have a 5-kilowatt hours (kWh) panel and a 2.5 kWh inverter, we can divide the former by the latter to get an inverter load ratio of 2.
An inverter load ratio of 1.1–1.3 is generally considered the sweet spot.
This is because the extra DC energy generated can be utilised during “power-limiting” periods; for example during winter when the sun doesn’t produce much energy.
This ratio also ensures that minimal power loss through clipping occurs during such periods.
Conversely, an inverter load ratio above 1.5 is considered bad because it leads to excessive clipping.
Many manufacturers have clauses against excessive clipping and will be quick to void your warranty if they suspect it.
Excessive clipping will also put more stress on your inverter’s transistors, making them wear out more quickly.
Pro Tip: A good way to reduce excessive clipping and optimise your residential apartment’s AC power output is to purchase a Victron Phoenix Inverter Compact 48V / 3000VA PIN483020000.
“It has a maximum AC power output of 5 kWh, which can support the average power consumption of large Australian households with ease.”
How does this come about? Well, while power consumption in Australian households differs by state, the average Australian 5+ person household consumes 2,205 kWh of electricity yearly, which translates to 6.04 kWh daily.
Dividing this power consumption by the maximum AC power output gives us an inverter load ratio of 1:2. This means that if you use the Victron Energy Phoenix Smart 18.6-34VDC input-output VPSINV-24/1600 inverter, you’ll be within the sweet spot.
3. Modern Inverters Can Be Accessed Remotely
The days of manually collecting data displayed by solar power inverter screens are long gone.
Modern inverters are fitted with smart devices, which can assess the performance of various components within solar equipment in real-time, and transmit the information directly to your phone via Bluetooth, wifi or the internet.
This makes it much easier for you to know:
- The power production of your solar panels (input voltage)
- The energy consumption of your house (output voltage)
- Temperature levels
- Battery levels
This is advantageous as the information provided allows you to optimise the performance of your solar panel when you see its performance drop, or spot a fault in the electric unit.
Pro Tip: Victron Energy Phoenix Smart Inverter 9.3-17 VDC input - output VPSINV-12/1600 is a modern smart inverter with a built-in Bluetooth system. This means you can configure it to your smartphone or tablet for efficient power monitoring.
To Choose a Solar Power Inverter Is to Choose the Future
Modern inverters are the superstars of the green revolution. Without them, solar panels are barely useful.
For this reason, you should choose the inverter that suits your needs perfectly.
Victron Energy has some of the best solar power inverters on the market. Here’s how they compare.
|Victron Energy Phoenix Smart Inverter 18.6-34VDC Input - Output VPSINV-24/1600
|Victron Phoenix Inverter Compact 48V / 3000VA PIN483020000
|Victron Energy Phoenix Smart Inverter 9.3-17 VDC Input - Output VPSINV-12/1600
|230 VAC ±2%
These inverters are so good that one prominent solar power component reviewer happened to mention:
“For small-scale systems (below 6kW PV), the Victron Inverters offer some of the highest quality and best value compared to the many cheaper, low-quality options available.”
You can purchase these pocket-friendly devices at Off Grid Direct.
Off Grid Direct is a modern eCommerce platform that specialises in selling efficient and sustainable portable power solutions and electronic devices for your off-grid systems.
Share on Facebook: