Buying a Solar Panel Inverter: The Function
An inverter is a crucial component in a solar panel installation. It converts the direct current (DC) generated by the panels into alternating current (AC), which is used to power your home. Inverters come in various shapes and sizes, depending on whether you have a series (string) or parallel system. In this article, we explain what to consider when purchasing a solar panel inverter.
The Function of an Inverter
Let’s start with the basics: the function of an inverter. The inverter is connected to the solar panels via DC cables. The direct current (DC) generated by the solar panels flows through these cables to the inverter. The inverter then converts the DC into alternating current (AC). The AC is sent from the inverter to the meter box through an AC cable (power cable). From there, the power is distributed throughout your home or sent back to the grid.
Buying Solar Panel Inverters
At OptimaSolar, we use inverters from trusted brands such as Solis and SolarEdge. Additionally, we install micro-inverters from Enphase and APsystems, which we’ll explore further in this article. Solis inverters are designed for serial solar systems, while inverters and optimizers from SolarEdge are used in parallel solar systems. In a parallel system, each solar panel is equipped with an optimizer, ensuring that the panels operate independently of one another and maintain optimal voltage. With a Solis inverter, the weakest solar panel in the series determines the performance of the entire system. However, this issue can be addressed by placing a Tigo optimizer under the underperforming panel.
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Mini Inverters for Solar Panels
There are also smaller models of inverters, which are ideal if the inverter is going to be installed indoors, as they take up minimal space. These compact models are often referred to as “mini inverters.” Solis offers mini inverters with capacities up to 3.6 kW. Inverters with capacities above 4 kW tend to be slightly larger. Additionally, SolarEdge’s Home Wave series also provides relatively compact inverters.
Mini Inverter Exceptions
A solar panel system can only be connected to a mini inverter if there is a single roof area. This is because mini inverters typically have only one Maximum Power Point Tracking (MPPT) feature. When there are multiple roof surfaces, a larger inverter is required, starting at 2.5 kW.
Additionally, with a three-phase system, a larger inverter is necessary compared to the mini models, as three-phase inverters start at 3 kW. This applies to both SolarEdge and Solis models.
Positioning the Inverter for Solar Panels
The routing of the cabling depends on the room where the inverter will be installed. It is important to place the inverter in a room with proper ventilation, as it generates heat and needs to dissipate it effectively. We also recommend avoiding rooms that are excessively dusty. Typically, inverters are installed in spaces like attics, barns, or garages. The inverter is connected to the meter box using a power cable.
Solar Panel System with Micro Inverters
In addition to central inverters, there is a smaller alternative known as the micro inverter, which is mounted directly under each solar panel. This is also referred to as a “solar panel with its own inverter.” A system equipped with micro inverters operates in parallel. If one micro inverter fails, the remaining panels will continue to generate power. The same applies when one panel is shaded. Furthermore, expanding your solar system with additional panels is much easier when using a system without a central inverter. Therefore, choosing solar panels with micro inverters offers several advantages. OptimaSolar uses micro inverters from Enphase and, since July 1, also from APsystems.
Connecting Micro Inverters to the Fuse Box
Micro inverters do not require DC cables. Instead, they are connected to one another using Q-cables (from Enphase Energy) or bus cables (from APsystems). These cables are then linked to the power cable in a junction box. From there, the supply cable, known as the AC cable, is routed to the fuse box. On the roof, the micro inverters convert the direct current (DC) generated by the solar panels into alternating current (AC).
Typically, the AC cable is run along the downspout, but it can also be routed through a dead-end pipe inside the house or via a crawl space. This setup allows the micro inverters to be connected to the fuse box.
Inverter Solar Panel Price
The number of solar panels you have will determine the required capacity of the inverter. In a series solar panel system, the inverter is typically less expensive than in a parallel system. For example, with brands like SolarEdge, Enphase, and APsystems, each has its pricing structure. An Enphase system tends to be slightly more expensive than a SolarEdge system because each panel has its own microinverter. On the other hand, APsystems offers a good middle ground, as it connects multiple panels to a single microinverter, offering a more cost-effective solution while still providing the benefits of a microinverter system. The best inverter choice for you, however, depends on your specific needs and situation.
Are you interested? Feel free to schedule an appointment for a free quote.
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We are very happy with our solar installation from OptimaSolar. Wim took the time to meet us at our house to give us advice and estimations. The work was carried out very neat and tidy and Wim himself... [ lees meer ]
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Got quotes from 3 other solar panel vendors, found optima solar the best for the price i paid. Panels were installed ontime with the perfection.... After sales support is also excellet. Thankyou.
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