Solar Inverters: Choosing the best one for your roof
Having a good quality solar inverter is a critical part of your solar PV system and choosing the right kind for your roof is an important decision for optimum production. With so many options around it is hard to choose. But with some basic knowledge you will find it is quite easy. In this post we share some simple checks that will help you decide on the type of solar inverter.
|Type of Inverter||Pros||Cons||Suitability||Our top picks|
|String Inverter||• Easy maintenance • No electronics on roof • Economical||• PV system non-expandable • Single panel defect affects entire system||• Roofs with minimal-to-no shading • PV system expansion not required||• GoodWe • Growatt • Solis • SMA|
|Micro Inverter||• Shading or defect on some panels will not cause complete power loss • Easy to detect faults • Individual panel performance can be monitored||• Expensive • Electronics located on roof • Experts are required for maintenance||• Roofs with significant shading on specific areas • PV system where panels need to be placed on multiple roofs • PV system with possibility of future expansion||• Enphase|
|String Inverter with optimizer||• Individual panel performance is optimized • Easy to detect faults of both system and individual panels • Individual panel performance can be monitored||• Some electronics located on roof – expert required for maintenance • System expansion might require changing central inverter||• Roofs with some shading in specific areas • PV system where panels need to be placed on multiple roofs||• SolarEdge|
What Is A Solar Inverter?
Electricity is generally in the form of either direct current (DC) or alternating current (AC). Solar panels generate DC, while typically all power outlets bring power in the form of AC, which is the requirement for most household appliances as well. A solar inverter is an electrical device which converts the direct current output from the solar panels into an alternating current to be used by your appliances.
Types of Solar Inverters
There are three types of solar inverters available in the market: String inverters, Micro Inverters, and String Inverters with power optimisers.
A PV setup with a string inverter, consists of a single central solar inverter to which all the panels are connected through a common string. String inverters are generally the most economical option for a PV system, and are usually easier to maintain as they need not be placed on the roof and can be placed inside the house.
The maximum production of a string inverter is equivalent to that of the least productive panel. For the same reason, it is not recommended to choose a string inverter in the event that some areas of your roof are subject to significant shading, as this can lead to overall reduction of your power production.
On the other hand, if there is plenty of sunlight, no significant shading, and no possibility to expand your PV system in the future, then a string inverter is an excellent choice. If you have plans to expand your PV system in the future, then our experts can suggest the maximum inverter oversizing possible with a string inverter.
A single micro-inverter is connected to each individual panel, in such a setup. In such a PV system, the micro-inverter converts the DC power of each panel on the spot to AC.
As micro inverters produce current individually, it is the most optimum choice for a roof with shading in some areas, or if there is a possibility of obstruction on some panels. Also in the event that there is some system malfunction, it is easier to identify which panel or micro is flawed, and just replace that individual unit. Micro inverters are typically more expensive than string inverters, but depending on your roof characteristics, it could give you the most optimized production outputs.
If you plan on expanding your PV system in the future, or have shading in very specific areas, then a micro-inverter is the optimum choice.
String Inverters with power optimisers
Such a PV system consists of a single central inverter, with individual power optimizers connected to each panel. These power optimizers optimize the DC output from each of the panels, and send the total optimized power to the central string inverter.
Power optimizers can be considered as economical substitutes for micro-inverters. Although they do not convert DC to AC at the panel site directly, their optimizing function can help to improve performance in case of partial shading on your roof. Similar to micro-inverters, it is possible to locate faults at specific sites with power optimizers.
If you have plans to expand your PV system in the future, then our experts can suggest the maximum inverter oversizing possible for the central inverter, and the additional optimizers can be added later. However, only minor expansion is possible without changing the central inverter.
Are you looking to install a PV system on your roof? Team Umagine is here to help you make an informed decision based on your roof characteristics, and take care of your individual requirements.
Get in touch with us today to get a free solar quotation, or we would also be happy to have a chat with you and discuss your needs to help you decide what is best for you.
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