Single-Phase Inverter VS. 3 Phase Solar Inverter: Which Is Better For You When Using Solar Power?

Much depends on the area you live and the general location of your house, you may be reliant on single-phase or 3 phase inverters, possibly using solar power through the conversion using 3 phase solar inverters. Or, maybe you have just moved houses and found you have a 3 phase energy supply and are trying to decide whether to use single-phase or if it is worth spending the extra for the 3 phase inverter? It is a good choice to use solar energy for your household, now let’s discuss what the best choice is to convert this solar energy to your useable electricity.


Single-phase solar power and 3 phase solar power

Single-phase and 3 phase are used to convert, distribute and transmit electricity across the household. Whether or not you use a single-phase or 3 phase system is dependent on the location you live and other external factors such as how much electricity you use on average. If your house is run on a single-phase system, this means that electricity runs in and out of your household in a single cable/circuit, or phase. Conversely, if you have a 3 phase system connection, the electricity that is transmitted through your household is distributed in 3 different phases (three cables/circuits). In this instance, you can have one item using electricity i.e. Refrigerator, whilst the washing machine and lights in another room run on the two other phases.


What phase do you have and how will it affect your solar energy system?

 a man installing solar panels

You must first determine which phase your household runs on, to determine how it will affect your solar energy system. If you go to your electricity box, you should be able to see (carefully) what phase system your household runs on. In the simplest terms, if your house runs on a single-phase system, you should install a single-phase solar inverter. If your household is running on a 3 phase connection, you have more options available to you, but like having a single-phase connection, there is one option that is best and fits for most households and situations. That is to get a 3 phase solar inverter, which will distribute the converted electricity evenly among the household. If the solar system you intend to install is small (<3kw), then you can opt to install a single-phase solar inverter onto one of the phases, specifically one with the heaviest power load. It is important to ensure the solar system is small enough for this option, as the system could be too large and the solar inverter will crash and ‘trip out’ due to the increased ‘over-voltage’. In addition to this, the solar energy that is received may not transmit to the required phase, where it may be required. Assess whether you can use the 3 phase solar inverter, and use this option if it is relevant to your situation. A third and final option is to install 3 separate single-phase solar inverters on each of the phases. This will ultimately make the system more stable/durable and help to transmit the converted solar energy across the household where it is needed, however, this option is much more expensive than the other two options and will have a higher initial expenditure cost.


If ever in doubt, it is important to call in a solar system fitter assessor to check your system and assess what the best option may be in relation to your household situation. This is the only sure-fire way to find what is the best fit for you and can ensure that you don’t make any mistakes that may affect the future of your single-phase or 3 phase solar inverter system.