It depends. Definitely not in a scenario where a perfectly good String Inverter will do the job.
Did your solar salesman try selling you Microinverters, and rubbish other inverters?
If you are being told that Microinverters will allow easy expansion of the system later we can inform them you;-
- Expansion in QLD is limited by size of inverter so max with micro inverters would be 4.95 kW cumulative output without special permission
- 5 kW string inverter like Suntwins has an output of 4.95kW and can be increased to 6 kW in panels which will provide more power at less price than the micro inverter system
- QLD Energex is looking to limit residential systems to 3kW after Sept 30th and inverters over 3 kW total have to be reactive technology. So not much time for them to further expand their system if not installing in one go. Possible that micro’s will go up in price, reactive string inverters are already available at same price. If a 5kW string inverter is already fitted this will not be a problem as new regulations are not retrospective and more panels can be added up to the CEC recommended max of 20%.
- Micro-inverters are only of use when severe shading problems exist due to increased price/power produced ratio
- Salesmen selling micro’s are doing so for higher commissions based on the higher price and are using the higher efficiency rating of the units as a point of difference, but do not explain the short-comings of regulations in Energex area when compared to the cheaper and higher production from an overloaded string inverter system.