What Is an On Grid Solar Inverter?
An on grid solar inverter is an apparatus that converts DC electricity produced by solar panels into alternating current electricity that can be utilized in homes, industries, and the public grid system. This conversion is essential to make the electricity produced by a solar photovoltaic system usable; otherwise, it would remain unusable.
In a grid-connected solar system, solar panels collect solar energy from the sun to produce DC electricity. This DC electricity is then converted into alternating current electricity that has a voltage and a frequency close to that of the grid system. Once it has been converted into alternating current electricity, it can then be utilized to power electrical devices or fed into the grid if it is more than what is required to meet local needs.
The solar inverter is considered to be the brain of a solar system as it controls the conversion of electricity produced by solar panels into usable electricity that can be utilized to meet local needs as well as to supply excess to the grid system.
How an On Grid Solar Inverter Works in a Solar System
A grid-connected solar system has a fairly simple flow of energy, but it is the inverter that enables everything to function in harmony.
Converting Solar DC Power into Grid-Ready AC Power
Solar panel systems use direct current to generate electricity, while most appliances and the grid use alternating current. An on grid solar inverter is necessary to convert the current so that it can be used to run common appliances.
The conversion of current types involves several steps:
- DC current from solar panels is fed into the inverter.
- Electronic components inside the inverter control the flow of current.
- AC current is generated at a voltage equal to that of the grid.
- The current then travels to a connection point in the house.
According to the University of Central Florida’s Florida Solar Energy Center publication Types of PV Systems, grid-connected photovoltaic systems use inverters to convert DC power generated by solar modules to AC power that is appropriate for use in buildings, as well as interaction with the grid.
This process is continuous as long as power is being generated by the solar system.
Synchronizing With the Utility Grid
In addition to conversion, a grid-connected inverter needs to have electrical characteristics similar to those of the grid. If not, there is no way to export power.
In order to maintain stability, an on-grid inverter is designed to monitor the following parameters:
- Grid voltage
- Grid frequency
- Phase alignment
- Power output
In case the grid goes down or the power lines are cut off, the inverter will turn off as a safety precaution for the utility workers. This feature is also referred to as anti-islanding protection.
Key Components of an On Grid Solar Power System
In order to appreciate the role that the inverter plays in the system, it is important to have an overview of the system itself. A grid-connected solar power system is composed of several key components.
| Component | Function |
| Solar panels | Capture sunlight and produce DC electricity |
| On grid solar inverter | Converts DC electricity into grid-compatible AC |
| Electrical panel | Distributes electricity throughout the building |
| Utility meter | Tracks electricity imported from or exported to the grid |
| Grid connection | Allows energy exchange between the building and the utility network |
Of these elements, the inverter is essentially the link between solar power and general electricity usage.
Advantages of Using an On Grid Solar Inverter
Grid-connected systems have dominated the global market for solar energy systems due to various reasons and benefits.
Higher Energy Efficiency
Grid-connected systems are more energy-efficient due to the absence of energy loss that comes with storage in batteries.
Lower Installation Costs
Grid-connected systems are advantageous in that they do not require batteries for storage, which is a costly aspect of installing a solar energy system.
Ability to Export Excess Electricity
However, in cases where the solar power generated is more than the household needs, the surplus electrical power can always be fed back into the grid. This is because the surplus power is enough for net metering and feed-in tariffs.
Reliable Power Supply
A solar power system connected to the grid uses the grid as an auxiliary source of power. This is because the grid always supplies power during the night and when the sun is not shining.
On Grid vs Off Grid Solar Inverters
Solar inverters can sometimes be divided according to whether or not they connect to the utility grid. Understanding these differences will help us determine when to use an on grid type of solar inverter.
On Grid Solar Inverters
An on grid type of solar inverter is one that only operates while connected to the grid. Its main features are:
- Direct synchronization with grid voltage and frequency
- Ability to shut down during grid outages
- Ability to export power
This type is mostly found in cities and townships where there is grid power.
Off Grid Solar Inverters
Off-grid inverters are not connected to the grid; instead, they are connected to a battery bank that will be used to store energy for later use. The main characteristics include:
- Energy storage integration
- Independent power supply in remote areas
- Increased system complexity and cost
Off-grid systems are mainly used in remote areas, rural homes, and areas without proper electric grid infrastructure.
Hybrid Inverters
The third type of inverter is a hybrid inverter that incorporates some characteristics from both off-grid and grid-tie inverters. It has the capacity to connect to the grid and also connect to a battery bank for energy storage.
When Is an On Grid Solar Inverter the Best Choice?
For the majority of households and businesses connected to the grid, an on-grid solar inverter is the way to go. There are several reasons why this type of solar inverter is the best choice for the average home or business.
The first is that grid-tied solar systems make the best use of solar power without the need for expensive battery banks.
The second is that the ability to feed excess energy back into the grid may help increase the return on a solar system. Energy credits may help reduce the payback period for the solar system.
The third is that the solar grid-tied system is an established technology with the support of solar installers and manufacturers. This means that the solar system will be compatible with the relevant electrical and grid regulations.
The last is that grid-tied solar systems are easier to maintain compared with other types of solar systems.
Why the Inverter Is the Most Critical Part of a Solar System
Solar panels, of course, tend to get the most attention, especially in marketing materials, while experienced installers often stress the significance of the inverter.
This is because, while solar panels do generate power, the inverter is actually what enables us to use that power effectively.
A good inverter design ensures that there is:
- Effective energy conversion
- Safe grid synchronization
- Monitoring and diagnostics
- Protection against electrical faults
With many modern installations, the inverter even enables real-time monitoring using mobile apps or monitoring tools, giving users a better idea of how their system is performing, as well as any possible problems.
Conclusion
An on grid solar inverter is the main device that makes the solar panels function in complete synchronization with the public electricity grid. The device converts the DC power from the solar panels into AC power, which can be used directly in homes and businesses while still allowing the user to be on the grid.
For the majority of homes with access to the grid, on grid solar systems are the best choice in terms of balance, cost, and efficiency. The systems are efficient, reliable, and cost-effective, as they eliminate the need for batteries while still allowing the user to sell excess energy back into the grid during the day.
If you are thinking of installing solar panels, the type of inverter used is one of the first factors you need to consider. The selection of a good quality on grid solar inverter that suits your needs will have a direct impact on the performance, quality, and value of your solar investment.
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