If solar panels are the muscle of your solar energy system, then the inverter is its brain. Together, they ensure you receive the most electricity possible. Most people are familiar with solar panels, as they are the most apparent component of a solar power system. But, the solar inverter is an equally vital component to consider, since it converts solar energy into usable electricity for your home.
This article examines what a solar inverter performs, how solar inverters function, why solar inverters are necessary, and how much a solar inverter costs.
How Solar Inverters Operate
Solar panels produce Direct Current (DC) electricity, but your home uses Alternating Current (AC) electricity, thus you have a problem: Your home requires assistance to use solar energy. This is when a solar inverter comes into play.
What exactly is an inverter? The principal function of a solar panel inverter is to convert the DC electricity generated by solar panels into home-usable AC electricity. Due to this, the solar inverter can also be referred to as a solar converter.
As most appliances require AC power, your solar power system must transform the DC energy into usable electricity before it can be used to power these products. The inverter is the brains behind this conversion, allowing your solar power system to provide energy to your electronic gadgets.
Check out How Does Solar Energy Work for a more detailed description of this process.
In addition, when a solar-powered home is connected to the electric grid, the inverter for home energy works as an intermediary between the home and the electric grid. This is known as a grid-connected inverter. A grid-tied inverter ensures that your home receives uninterrupted electricity, regardless of how much energy your solar panels produce.
In the event that your solar power system generates more electricity than your home needs, the photovoltaic inverter can feed the excess electricity back into the grid. Nevertheless, if your solar panels are producing some electricity but not enough to power your full home, the inverter will combine solar power with grid power.
During night, when solar panels are not producing electricity, your home may require 100 percent of its energy from the grid, or the inverter may be able to combine grid power with energy saved in solar batteries.
In either case, the grid-tie inverter is responsible for ensuring that your home has sufficient power in any of these situations, and you will not notice a difference as it shifts between them.
DC versus AC Electrical
The most appropriate response to “What does an inverter do?
to comprehend the distinction between DC and AC power.
Direct Current (DC) electricity involves a unidirectional flow of electric charge. In contrast, Alternate Current (AC) electricity occurs when the flow of the current changes direction (or alternates direction).
The electric grid in the United States uses 60 hertz alternating current, which means that the power flips direction 60 times each second.
When the sun’s rays strike photovoltaic (PV) panels, they cause the solar cells’ electrons to move. Its movement is in a single direction, which generates DC electricity. The circuits within your solar panels gather this current and send it to the solar PV inverter, which converts the DC current to AC electricity.
The advantages of a solar inverter
Although your solar PV converter allows you to obtain useful current from the sun’s rays, it is capable of much more. A solar panel inverter can help you maximize energy production, monitor your system’s output, communicate with the utility grid, and detect flaws that could otherwise cause damage to your solar power system.
Optimising Energy Generation
Solar inverters monitor the voltage of your solar array to maximize the power at which your solar panels work, allowing you to create the most energy and the cleanest electricity possible.
Grid-connected home solar inverters also produce a more pure sine wave (a measure of how smoothly the direction of the current changes) than low-cost inverters, ensuring that your sensitive appliances operate smoothly and efficiently.
Monitoring System Performance
On a bright day, it’s wonderful to watch your solar power system create thousands of watts, so it’s only natural that most homeowners desire a means to track the effectiveness of their investment.
Some solar panel inverters allow you to track the performance of your solar system via a mobile app or website. the majority of solar panel inverters include a method for viewing the amount of energy they are currently producing.
Some house inverters will automatically evaluate the operation of your solar power system and inform you if it finds a problem with any component if things aren’t working properly. Also, you can utilize the home inverter’s performance tracking to monitor how your system’s components are operating and ensure that it is producing the correct quantity of electricity.
Transmissions Using the Utilities Grid
In the event of a brief power loss, solar inverters prevent electricity from your panels from being routed to external power lines. Hence, line workers who are inspecting or repairing the grid will be shielded from harm.
If you have a full solar battery bank or if your home doesn’t use all of the solar electricity generated, the inverter can also feed the excess electricity into the grid to help you earn net energy credits.
Defect Detection
If not properly maintained, aging and deterioration of your electrical wiring and solar equipment might result in hazardous electrical problems such as ground faults or arcs. In the event of such an occurrence, the solar power inverter will immediately detect the problem and shut down, protecting the rest of the system and alerting you to the need for service before more harm happens.
Comparing Several Solar Inverter Models
The solar power inverters your solar company will employ rely on the intricacy of your roof, the amount and frequency of shade on your roof, the purpose of your solar power usage, your residential area’s utility regulations, the manufacturers they’ve partnered with, and other variables.
String inverters, microinverters, power optimizers, and hybrid inverters are the four primary types of solar power inverters, and each has advantages and downsides.
String Inverter
A string inverter, sometimes known as a “central” inverter, is appropriate for simpler solar power system designs. A string is a collection of solar panels, and multiple strings can be connected to a single central inverter. From the panels, the electrical energy travels to the central inverter, which transforms the DC electricity to AC electricity before making it available to power your home.
A string inverter is the easiest to maintain because it is typically located in a basement, garage, or other easily accessible area. It is also the least expensive option, as only one inverter is required to accommodate many panels over multiple roof planes. Lastly, a string inverter is typically more durable due to its simpler design and more fundamental function.
The disadvantage of a string inverter is that poor performance in one panel can affect the performance of the other panels in the string. Since a string inverter cannot optimize the performance of each individual panel, it is not suitable for roofs with consistent shade. In addition, a string inverter performs poorly in complex system designs where panels cannot be simply grouped into strings.
If you choose a low-cost solution and your home’s roof has a simple design and receives regular sunlight, a string inverter is typically the best choice.
Microinverters
In contrast to string inverters, microinverters are scattered, and a miniature inverter is positioned next to each solar panel. Instead of power traveling from all panels to a single inverter before being converted, this technology converts direct current to alternating current at each panel.
Microinverters are an excellent option for homes with complex solar array designs or consistent roof shading. They optimize the performance of each panel at the site to limit the impacts of shade, and you may monitor the output of your system at each panel.
Due to the fact that each additional panel comes with its own inverter, microinverters might also make it easier to expand your system in the future. With a string inverter, the inverter is typically sized for the amount of panels that will be initially placed and is not designed to accommodate further electricity generation.
Microinverters have the disadvantage of being more expensive than string inverters. However, since they are positioned on the roof, maintenance can be more difficult if they require servicing.
Microinverters are ideal for maximizing energy output on complex roofs where panels face different directions or in shaded areas.
Power Optimizers
Optimizers are a compromise between microinverters and string inverters. Similar to a string inverter, the electricity from your solar panels is transmitted to a central inverter. Unlike microinverters, power optimizers are situated adjacent to individual solar panels.
Before transmitting power to the string inverter, power optimizers optimize the voltage of the electricity (thus conditioning the DC electricity). By optimizing the output of each panel, they can limit the impacts of shading on any given panel.
If your home has a complex roof (think roofs with chimneys, gables, and other obstructions), power optimizers can also assist with optimizing your system for these obstacles.
The primary disadvantage of power optimizers is that they are more expensive than standard string inverters, but they normally cost less than microinverters. Similarly to microinverters, power optimizers can complicate maintenance.
If your roof is more complex and you want to boost performance without investing in microinverters, the best solution is power optimizers.
Hybrid Inverter
The newest addition to the field of solar energy inverters are hybrid inverters. The hybrid inverter is a mix of a photovoltaic inverter and a battery inverter, and it is available in both a straight string configuration and an optimized string configuration.
The primary benefit of a hybrid inverter is that it can convert electricity in both directions, so it can convert DC power from solar panels to AC power for the home, and it can also convert AC power from the grid to DC power to charge a solar battery or an electric vehicle.
Homeowners seeking energy backup solutions are adopting this technology since it can be installed similarly to a conventional inverter, and adding a battery to the system does not impose a significant cost premium.
Once you have this battery, you can draw energy from the grid to charge it, allowing you to store energy when it’s more inexpensive and use it when rates are higher and solar power isn’t meeting all of your needs.
Since the number of Electric Vehicles (EV) continues to rise, certain hybrid inverters have the extra capability of charging EVs. Since an EV charger can be connected directly to the hybrid inverter, main panel improvements are not necessary.
Again, the primary disadvantage is cost, and hybrid inverters are similar to string inverters, thus they are not as adaptable to complex roof designs or shading.
Hybrid inverters are a wonderful alternative for those who are contemplating energy storage solutions or have plans to add a solar-charged electric vehicle.
Solar Inverter Productivity
During the conversion of DC to AC electricity by the inverter, some energy is wasted as heat. Better grade solar power inverters are more efficient, thus they convert more electricity without incurring significant losses.
The conversion efficiency varies by model, but the majority of quality inverters are between 97% and 99% efficient, therefore energy loss is minimal. Nevertheless, shading and other factors can have an effect on the efficiency of an energy system, and your photovoltaic inverter plays a part in limiting these losses.
Solar Inverter Sizing
Typically, inverter manufacturers indicate both the maximum input energy their products can accept and the maximum output power. For example, a string inverter with a maximum input energy of 4,000 watts may accommodate up to 4,000 watts of solar panel energy.
In practice, you will rarely obtain the power rating shown on your inverter’s nameplate (achieved at Standard Test Conditions, or STC). In fact, your usual everyday activities could reduce the power rating by as much as 20%.
To reduce costs, solar power inverters with a maximum input power lower than your solar panel’s maximum output are frequently chosen. This results in some clipping at maximum power generation, as the system is not designed to manage the maximum amount of power that the panels can generate, as this level of power is rarely reached on a typical day.
Inverter Clipping
When building a solar power system, it is essential to match the photovoltaic inverter size to the solar array size for optimal power conversion. You may be surprised to hear that it is typically not a perfect match, and just because you have 5kW of solar panels does not necessarily imply you would combine them with a 5kW inverter.
Normally, it is more cost-effective to select an inverter that can handle less electricity than the maximum amount of power that the solar panels can produce. Clipping occurs when the solar panels produce more electricity than the inverter can handle, resulting in the loss of excess energy.
If you imagine electricity production as a wave, which rises as the sun rises higher in the sky and delivers more direct sunlight, then inverter clipping simply refers to the cutting off of the wave’s peak.
Nonetheless, it makes sense to “throw away” this excess power because solar panel arrays rarely reach their maximum output. It is preferable to design the system to manage the expected amount of electricity, even if it means losing a little amount of capacity on exceptionally productive days. If you construct a system to accommodate the maximum amount of power generation, the majority of that capacity will go unused on average days.
Local Inverter Solar Regulations
A qualified solar installer will be aware of any local restrictions governing the use of solar energy and any net metering requirements and connectivity regulations. For instance, in many states, to qualify for net metering, your solar system must conform to a specified maximum size or maximum amount of energy produced as a proportion of your average use.
The system’s size limit is normally determined by your inverter’s maximum energy production, not your panels’ maximum energy output, as this decides the total amount of energy your installation can feed back into the grid.
What is the cost of a solar inverter?
It is difficult to estimate the price of a solar PV inverter because the design of each system is unique. The size of the photovoltaic inverter can be scaled up or down based on your home’s energy requirements and the architecture of the photovoltaic system.
In addition, installers frequently purchase in bulk and have direct contacts with suppliers, so their prices may differ from those of direct purchasers.
String inverter prices normally range from $1,000 to $2,000 or more, depending on criteria such as the size of the system, the type of solar agreement, the seller, and any local peculiarities.
Keep in mind that you will need one power optimizer per solar panel and an inverter to link them.
Microinverters are more expensive than string inverters, often costing $1,000 or more more than string inverters of comparable size. Remember that string inverter size can be increased with a reduced incremental cost, thus a twice as large string inverter is not necessarily twice as expensive. In contrast, microinverters must be installed on each panel, so doubling the number of panels will likely result in a doubling in inverter costs.
How long do solar inverters typically last?
String inverters normally have a lifespan of 10 to 15 years, but can survive up to 20 years if installed in a cool, well-ventilated position and carefully maintained.
Microinverters and power optimizers are very new to the market, hence there is less information regarding their predicted lifespan. Nonetheless, the majority of manufacturers are sure that their devices will outlast the 20- to 25-year warranties that accompany them.
Which Inverter Is Appropriate for My House?
Using our free Solar Savings Calculator is a simple way to get started if you’re considering investing in a solar power system for your house and deciding which inverter option is ideal for you.
You will receive an estimate of the amount of money you would save by installing solar panels on your home, which factors in regional installation requirements, such as the type of inverter that is typically advised.
You will also be linked with a solar professional who can analyze the various solar solutions that make sense for your home, including inverter possibilities, and help you choose the one that best suits your family’s requirements.
