Photovoltaic solar inverters are equipment that is responsible for transforming the energy produced in a photovoltaic installation, which is transmitted in the form of direct current, in alternating current so that electrical appliances and other electrical products can operate at their normal levels.
What are photovoltaic inverters?
Now we will try to understand how investors work and the different types that we can find in the market.
How do photovoltaic inverters work?
When our photovoltaic panels receive sunlight, the electrons begin to move inside the solar cells, which produces electricity from direct current. The circuits inside the photovoltaic cells collect that energy for us to use in our house.
This is where the solar inverter comes into play. Most homes use AC electricity, not direct current, so the energy produced by the solar panels is not useful by itself.
When solar panels collect sunlight and convert it into energy, it is sent to the inverter, which receives electricity from direct current and converts it into alternating current.
That is when solar electricity can power the appliances and electronic devices or, if we are producing more electricity than we need, store it in batteries or we could pour it into the electricity grid.
Main functions of the Photovoltaic Inverter
- Energy conversion : The solar photovoltaic inverter converts direct current into alternating current, which is the one used by all electrical appliances. It basically acts as a gateway between direct current and alternating current.
- Optimization of energy : Maximizes the generation of energy from solar panels. To do this, the panels are individually insulated in order to increase the production of energy, and therefore, improve the overall performance of the installation.
- Monitoring and protection : A solar inverter monitors the energy performance of the photovoltaic system, electrical activity and signals when problems arise. This information can be viewed on the device itself or from another location if the appropriate communication technology and online services are implemented.
- Constant operation : A photovoltaic installation is designed to provide power to the weather and in all weather conditions. The photovoltaic inverter offers a constant operation dissipating the heat in a consistent way.
Types of Photovoltaic Investors
All photovoltaic inverters have the same common task: converting solar DC power into useful AC power for our home. However, there are three different inverter technologies that we can choose for our solar panel system, and each of them works in a significantly different way.
String or chain inverters: a standard centralized inverter
Most small-scale solar energy systems use a chain inverter, also known as a “centralized” inverter. In a solar self-consumption installation with a chain inverter, each panel is connected in series.
When they produce energy, everything is sent to a single inverter, which is usually located on one side of the house, in the garage or in the basement. The investor converts all the green energy generated by your solar panels into electricity that you can use in your home or business
Pros : Chain inverters are the lowest cost option and they are a proven technology. They are also easy to maintain, since they are easily accessible.
Cons : If our system uses a string inverter, it will only produce as much useful electricity as the solar panel that produces least. The generation of electricity in an installation with a string inverter can suffer the “bottleneck” effect, or be drastically reduced, if only one or two of the panels are shaded or not working properly.
Ideal for : Housing with “unobstructed” roofs that consistently receive radiation throughout the day, and for owners seeking photovoltaic systems at the lowest cost.
If a string inverter can be considered as a “centralized” inverter, the microinverters are “distributed” inverters. In photovoltaic installations with microinverters each solar panel has a small solar inverter installed. Instead of sending power from all the panels to a single inverter, the micro-inverter systems convert solar DC power into AC power on the roof itself.
Pros : Microinverters are more efficient than string inverters. The installations of solar panels that enjoy this technology, continue to produce energy, even if one or two of the panels of the system have a lower performance. The microinverters also allow monitoring the performance of specific solar panels, which facilitates the identification of production problems if necessary.
Cons : Microinverters cost more than a chain inverter, and can be harder to maintain or repair in the event of a problem, since they are on the cover.
Ideal for : Installation with solar panels with different orientations, owners who want to maximize the production of solar energy in a small space, and houses that have “complicated” covers with pediments, chimneys or other objects that can cause shadows.
Power optimizers: an option located on the panel to connect to a chain inverter
Power optimizers can be considered as a compromise between chain inverters and microinverters. Like the microinverters, the power optimizers are located on the roof next to – or integrated with – the individual solar panels. However, systems with power optimizers continue to send power to a centralized inverter.
Power optimizers do not convert DC electricity into alternating current at the site of the solar panel. Rather, they “condition” electricity in direct current by setting the voltage of the electricity, at the moment it is sent to the photovoltaic inverter. An installation of solar panels with power optimizers is more efficient than one that only uses a chain inverter.
Pros : Like microinverters, power optimizers can improve the efficiency of the installation, and are less expensive than microinverters. They also offer the advantage of monitoring the performance of each solar panel individually, and reducing the effect of shadows on the performance of the installation.
Cons : An installation with power optimizers will cost more than an installation with a chain inverter.
Ideal for : Owners who are willing to pay more to increase the efficiency of their solar panel system, but who do not want to acquire in microinversores.
How to choose the best photovoltaic inverter option for your home or business?
Now that we understand how photovoltaic solar inverters work , the next step is to decide which type is best for our electrical self-consumption installation. In the end, the choice is reduced to how much we are willing to pay for additional performance, and if we are willing to pay for possible additional maintenance.
At SotySolar we can help you make that decision about your solar investor options. By registering your home, you will receive personalized offers from qualified installers, and you will be able to evaluate the costs and benefits of the different solar inverter options. We will accompany you during the process resolving any doubt that may arise. Start saving on your electricity bill, producing your own green energy.