Solar inverters are an essential part of any solar power system. They convert the direct current (DC) power produced by photovoltaic solar panels into alternating current (AC) electricity that powers the appliances and devices in most homes and businesses.
Choosing the correct solar inverter can be confusing, especially for beginners. This article explains solar inverter basics, including their functions, types, and applications.
We’ll walk you through the alternatives and recommend the leading solar inverter options on the market to help make your decision easy.
What is a Solar Inverter?
A solar inverter is essential to any solar power system. It converts the direct current (DC) electricity your photovoltaic (PV) solar panels produce into alternating current (AC) electricity, the type of electricity used in your home. An inverter is a balance of system component built into many solar generators or installed between your solar panels and your home’s electrical panel.
Inverters also have several other essential functions, such as monitoring and optimising the performance of your solar panels. In off-grid solar power systems, the energy converted into AC electricity by an inverter is stored in a solar battery. Without a solar inverter, the electricity produced by your solar panels would be unusable.
Solar inverters are a vital component of any solar power system. Without one, you can’t use the clean, renewable energy your panels produce to power your home.
What Do Inverters Do?
Inverters are devices that convert direct current (DC) electricity into alternating current (AC) electricity. The difference between DC vs. AC electricity comes down to a difference in conversion to higher or lower voltages, and inverters assist with that.
Inverters have a wide range of applications in solar power, battery backup, and renewable energy systems. Besides conversion, they optimise electrical system performance.
In solar power systems, inverters convert DC electricity into AC electricity for homes and businesses. Some solar systems include built-in inverters, such as the EcoFlow Solar Generators. Others require purchasing an inverter separately.
When used in battery backup systems, they allow for storing excess electricity in batteries during power outages or when renewable energy sources are unavailable.
In non-solar renewable energy systems, inverters convert electricity from wind turbines and hydroelectric generators into usable AC electricity. Inverters are essential in converting and distributing electricity.
Input and Output
Solar inverters have two primary input and output connections: the DC input from the photovoltaic panels and the AC output to your solar battery (or home electrical panel for grid-tied solar systems).
Types of Solar Inverters
The best type of solar inverter depends on how you’ve wired the panels to each other and your home.
String inverters are the original solar inverter technology and often the cheapest option. They convert the DC power from an entire string of panels into AC power for your home.
Shade — such as from trees obscuring part of your roof — is the biggest downfall with string inverters. When you have panels wired in strings, if one panel isn’t receiving sunlight (or is damaged), it will reduce the output of the entire array. Additionally, your solar power system won’t function if a string inverter goes down.
Micro inverters are a more recent technology. Smaller inverters attached to each solar panel convert the DC power to AC electricity before sending it to the balance of system.
According to researchers at the University of Virginia, a system that uses micro inverters is 27% more efficient than string inverters. It works better for roofs with varying angles or shaded spots, as the power produced by each panel is not dependent on the others.
Micro inverters cost more than string inverters for the initial installation, but the increased efficiency will likely pay off in the long run.
Power optimisers are similar to micro-inverters, with an inverter attached to the back of each photovoltaic panel. However, they do not convert the DC power to AC.
Instead, they standardise the DC power produced by each panel. The entire array is then connected in a string and sent through a string inverter. Power optimisers are also often referred to as DC optimisers or DC converters.
Hybrid inverters allow homeowners to utilise off-grid and on-grid power. They work exceptionally well with home battery backup.
A hybrid inverter can still convert the DC power from your solar array into AC power for your home. In addition, hybrid inverters can also convert AC power from the grid into DC power to charge your battery bank.
What Is the Right Size Solar Inverter?
Choosing the right size solar inverter is critical to ensure that your system is efficient and effective. The best size will depend on your solar power system size and your energy needs.
It’s essential to choose an inverter that is large enough to handle the output of your solar panels but not so large that you are wasting money on excess capacity. If you choose an inverter that’s too small, it may not be able to handle the output of your PV panels, leading to reduced performance and efficiency.
On the other hand, if you choose an inverter that’s too large, you’ll be paying for excess capacity that you don’t need.
To determine the correct size solar inverter for your system, it’s a good idea to consult with a solar installation professional or use an online inverter size calculator to help you determine the best size for your specific energy needs.
Read more: What Size Inverter Do I Need for My Motorhome?
Solar inverters have a wide range of applications in both residential and commercial settings.
In homes, solar inverters power everything from small appliances to large HVAC systems and can help homeowners save money on their energy bills — or eliminate them altogether. In addition, they can power office buildings, warehouses, and other extensive facilities in commercial settings, helping businesses reduce their energy costs and carbon footprint.
Solar inverters are also used in industrial environments, such as factories and power plants, to convert electricity from renewable sources. Inverters are an integral part of transitioning to a more sustainable energy future.
Solar Power Inverters: Grid-Tied, Off-Grid, & More
Solar inverters can work with grid-tied and off-grid systems, as well as hybrid systems. Grid-tied inverters are common and integrate with your home electrical panel. You can use grid power when needed. In some areas, you can sell electricity back to the grid through net metering.
Inverters are an essential component of off-grid solar power systems that offer true energy independence. With off-grid solar, you no longer have to worry about ageing infrastructure and power outages caused by extreme weather events. You can eliminate your electricity bills completely by generating enough clean, renewable solar energy to meet your power consumption needs.
Lastly, hybrid inverters combine solar and battery inverters into one component. Hybrid inverters typically will not work without a connection to functioning grid power — meaning that your system is unlikely to work in a power outage.
Choosing the Best Solar Inverter
When choosing a solar inverter, there are several important factors to consider:
- The size of your PV solar panel system
- Your energy consumption needs
- Whether you want to be off-grid or grid-tied
- Your budget
It is also a good idea to research and compare different brands and models to find the one that best meets your needs and budget. Consult with a solar installation professional to get expert advice on the best inverter for your specific situation.
Choose an inverter that is reliable and has a good warranty, as inverters can be expensive to repair or replace if they malfunction or fail.
EcoFlow Power Kits and Power Hub
Trying to choose an inverter and other components can become confusing. You can never be quite sure about compatibility between solar panels, batteries, inverters, and charge controllers. That’s why some companies have put together convenient all-in-one off-grid power solutions.
The EcoFlow Power Kits are an excellent example of a plug-and-play off-grid solar power system. They are perfect for cabins, tiny homes, and motorhomes.
The Power Hub includes all of the essential converters, outlets, and chargers for an off-grid system, including:
- DC-DC Step-Down Converter
- DC-DC Battery Charger with MPPT
- MPPT Solar Charge Controller
- Solar Inverter Charger
With an all-in-one system, you don’t need to worry about compatibility and whether the inverter is the right type for your solar power system. The Power Kits also work with all models of EcoFlow solar panels (rigid, portable, and flexible) and panels from other manufacturers.
EcoFlow’s Power Hub: What’s in the Box?
DC-DC Step-Down Converter
A DC-DC step-down converter takes the high voltage of PV panels (often 50+ volts) and steps it down to the 48V that the EcoFlow Power Kit batteries expect.
DC-DC Battery Charger with MPPT
The DC-DC battery charger with MPPT (multi-power point tracking) allows the battery bank to be charged directly by other DC power sources, such as a car alternator or a service battery.
An MPPT is especially useful in motorhomes and other mobile applications. The technology allows for high-efficiency charging and is superior to similar chargers that use PWM (pulse width modulation) chargers.
MPPT Solar Charge Controller
The integrated MPPT charge controller allows for safe, efficient charging of your battery bank using the power generated by your solar array.
Solar Inverter Charger
The inverter charger allows your system to charge and function using AC power. For example, with a motorhome installation, you can connect directly to shore power at campgrounds.
A solar inverter is essential to any solar power system. It allows modern AC appliances and devices to utilise the DC power generated by photovoltaic solar panels.
Choosing an inverter can be difficult, as many different models exist. Luckily, manufacturers like EcoFolw have created all-in-one systems that eliminate compatibility issues. EcoFlow’s Smart Home Ecosystem gives you the freedom to customise a solar power solution that’s right for your family’s needs — easily and without compatibility concerns.
Frequently Asked Questions
A solar inverter converts the direct current (DC) electricity your PV solar panels produce into alternating current (AC) electricity — the type of electricity used to run consumer appliances and electronics. Inverters also monitor and optimise your panels’ performance to ensure they safely produce as much electricity as possible.
The best inverter depends on your specific needs, although micro-inverters tend to be more efficient than string inverters. Some factors to consider when choosing an inverter include your PV solar panel system size, your energy consumption needs, whether you want to be off-grid or grid-tied, and your budget.
Grid-tied inverters do not require a battery, as they are connected to the utility grid and send excess electricity to the grid. On the other hand, off-grid inverters require a solar battery to store excess electricity. Some hybrid inverters can work with or without a battery, but most need the grid to be operational to function.
Switching to solar can require a substantial upfront investment — and an inverter is an essential component. Purchasing a solar power system is a long-term investment — it may take years of incremental savings on utility bills to exceed your upfront costs. Government subsidies and financing can help defray initial costs or spread them out over time.
When choosing an inverter, keep the long-term in mind — it’s not a good place to cut corners. Cheap inverters may break down frequently, require regular maintenance, and need to be replaced when broken for your balance of system (including solar panels and batteries) to function.