I hear good stories about the efficiency of so called “Micro-Inverters” on RenewableEnergy.com and Solarworld.com,
I like to hear from the Solar-professionals, since I am thinking about getting a 5 KW system myself.
Which one do you prefer?
Which one is better (according your own experience)?
Which one is more economical?
Which one has the highest efficiency?
Feel free to elobarate as much as you can about this technology, it is fascinating to me!
My only experience was installing a couple solar panel systems so far,and it was a central inverter system.
I hear the cost of micro inverters is relatively higher, and has both pros and cons.
While you are waiting for a response from someone in the field who has installed them. I found some info that may be helpful.
They are selling quite well in California and I would like to know myself from someone with personal experience.
Shading issues such as trees can dramatically reduce a solar system’s power production due to overhanging or close buildings structures. In fact, just 7-10% shade can influence up to 1/2 of the total system’s output. Micro-inverters significantly reduce this power loss by handling each solar module individually. String inverters can’t offer this so you loose long term trying to save money with it. If you have plenty of sunlight to harvest go with the one string inverter.
Micro inverters are cost effective only if your solar panels are distrbuted randomly around your property, if your panels are situated all together it would be cheaper to have them all on one inverter.
For example if you had one panel for your electric gate and two panels for a barn, those could use a micro inverter and battery, saving you the cost of wiring back to the house.
The last commenter was correct is stating that the efficiency is greater for partially shaded panels.
I prefer SMA AMerica. The TL series line allows for power during daylight houes when the sun is out and the grid is down.
I prefer the microinverters. As stated, they handle partial shading issues better during the day. More importantly, they allow flexiblity in design and future expansion. I also like how they can be individually monitored for performance, from your smart phone if you prefer.
Generally speaking microinverters tend to be a more expensive but better option. Individually they are less expensive, but you will need one for each panel which could run 120-300 per inverter. The nice thing about them is in the event one panel is shaded, you do not lose others on the same string. That being said there are other options that essentially act as a micro inverter and help with shade managment ( sunnyboy from SMA) that may be a more economical choice, but it is nice to only need to have the freedom to replace one little inverter instead of having one big one take down your whole grid.
Micro inverter have a very high failure rate. Go with SMA string inverters with free back-up power!
We have been in the industry for over 30 years and String Inverters is a way of the past for residential and commercial systems, on a large scale a string inverter can be beneficial from an investment standpoint but on a production standpoint micro inverters are becoming untouchable in performance and reliability.