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Basically, is it worth paying an extra £1400 for a system with micro invertors?

I'm about to build an extension and have permission to put an additional 4kw on its roof. The roof faces SSW but is lower than the house which is to the east. This means that the edge of my new array will get shading in the mornings.
I'm guessing it will make the biggest difference in the shoulder months when the sun will take longer to get high enough to fully summer on the array and it's then that those extra few kWh will be most valuable.
But how much difference will it really make?


As an aside, when I got my initial quote at the end of October the lead time from order to install was 2 months, I just discovered today that it is now 8 months. I think energy prices might be driving a bit of a solar boom!

We have it on one system. Made 7.5kWh today, the other system of a similar yet sligtly smaller size made 4.77kWh. There are shading and orientation issues/differences between the systems so i cant do apples to apples. In saying that If I was putting my money down again id likely go for extra panels if possible or put towards battery and later sling on a DC only second system. It worked for me,I honestly don't think any microinverter systems can keep up with the raw hp of more panels.

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If you have an install that is in anyway compromised from a shading point of view, or is a split orientation array, then SolarEdge is very much worth it. Don't underestimate how much damage to output having just one panel, or even one corner of one panel, makes to the entire array. They also claim to be more efficient overall in the inverter.

First of all Solar edge are not micro inverters which are a completely different technology and are hardly ever used. What your talking about are voltage optimisers. They work by altering the panel voltage to match the max power string current. They sort of help out the main inverter get the max power if panels are mismatched in some way.

Solar edge systems really come into their own if you try and make up a string of panels which face different directions, have different slopes, have different power ratings or have some complicated severe shading issues. Some people also like them because they have individual panel monitoring or some of the newer ones allow quite an oversized array to be used without DNO issues.

Sounds like your array SSW will not really benefit enough for both the outlay and the added complexity. Most decent inverters (like SMA) deal with shading if they have a global peak MPPT function and are set up properly.

That's all very useful, thanks for everyone's comments.

The existing 4kw system has no shade at all and I'm quite happy with its performance so I will be getting generation in the morning from them regardless of what I do.

The new system is my attempt to maximize panels on available roof space and it's only 2 panels that will get shaded in the morning so the return on £1400 will probably take a very long time.

Had a chat with my wife and we have decided to just go with the basic system. It's cheap (£4400 when they quoted in October) and should make a big difference to charging the car most of the time.

I'll earmark the money I could have spent to the hydro project I have in mind which is just waiting on finding 500m of cheap or free pipe..........

CM, a lot of companies will remote quote with no need for a site visit, worth a 2nd n 3rd quote maybe?